Table of Contents
From the Editors ......................................................................................................................................... 1
Letters to the Editors ................................................................................................................................... 2
RERF NewsThe Second Board of Councilors Meeting Held in Washington, DC.................................................... 3
Local Liaison Council Meetings Held in Hiroshima and Nagasaki ...................................................... 4
Chairman Toshiteru Okubo Takes Office as HICARE President .......................................................... 5
The Second Public Lecture Program for Citizens Held in Nagasaki .................................................... 6Open House Events in Hiroshima and Nagasaki................................................................................... 6
IPPNW Participants Visit RERF ........................................................................................................... 7
Visiting Scientists .................................................................................................................................. 8
Staff News ............................................................................................................................................. 8Awards Received by RERF Scientists ................................................................................................... 9
Conference and Workshop Reports
Future Plans and Structure for Research in the Basic Sciences at RERF,
by Evan B. Douple and Roy E. Shore ............................................................................................. 11
The 35th Meeting of the Japanese Society of Cancer Epidemiology, by Kotaro Ozasa ..................... 15
The Third Epidemiological Training Workshop for Biologists, by Nori Nakamura ........................... 17
The 58th Annual Meeting of the Radiation Research Society, by Evan B. Douple ............................ 18
Science Articles
Radiation Dose and Cataract Surgery Incidence in Atomic Bomb Survivors, 1986–2005,
by Kazuo Neriishi............................................................................................................................ 19
Long-term Trends of Thyroid Cancer Risk among Japanese Atomic-bomb Survivors:
60 Years after Exposure, by Kyoji Furukawa .................................................................................. 25
Human Interest Notes
Farewell Service and Memorial Gathering Held for the Late Dr. Itsuzo Shigematsu,
by Kazunori Kodama, Yutaka Ogasawara, and Ayako Ishibe .......................................................... 27
In Memoriam: Dr. Shoji Tokuoka, by Kazunori Kodama ................................................................... 29
Facts and Figures
Public Relations Activities at RERF, by Takanobu Teramoto ............................................................. 30
Recent Publications................................................................................................................................... 32
Cover photograph: Open House visitors examining blood cells through RERF
microscopes. Related articles on pages 6 and 30.
This newsletter is published twice a year by the Radiation Effects Research Foundation (RERF;
formerly the Atomic Bomb Casualty Commission), established in April 1975 as a private,nonprofit Japanese foundation. It is supported by the government of Japan through its Ministryof Health, Labour and Welfare and by the United States through its Department of Energy (DOE),
in part by DOE contract DE-HS0000031 with the National Academy of Sciences. RERF becamea public interest incorporated foundation on April 1, 2012.
RERF conducts research and studies—for peaceful purposes—on medical effects of radiation
and associated diseases in humans, with a view to contributing to maintenance of the health andwelfare of the atomic-bomb survivors and to enhancement of the health of all humankind.
Editor-in-Chief: Evan B. Douple, Associate Chief of ResearchTechnical Editor: Fumie Maruyama, Public Relations & Publications Office
Editorial Policy
Contributions to RERF Update receive editorial review only and do not receive scientific peer
review. The opinions expressed herein are those of the authors only and do not necessarily reflect
RERF policies or positions.
Contact: Mailing address: RERF Public Relations & Publications Office, 5-2 Hijiyama Park,
Minami-ku, Hiroshima 732-0815 Japan
Telephone: 81-82-261-3131; Facsimile: 81-82-263-7279
Internet: www.rerf.jp

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From the Editors

From the Editors
Welcome to RERF Update! It has been a longand exceptionally hot summer in Hiroshima,
but finally thebeautiful daysof early fallwith crisp, clear
morn ings andcool evenings havearrived on Hijiyama.
The blue of the sky
is mirrored in the perennial
morning glories (Ipomoea indica [Merr.]) that greet
RERF employees at the employee gate, and themaple leaves are finally turning red as the cool evenings signal that the transition from fall to winterwill soon begin.
This issue of Update includes in RERF News areport on the second Board of Councilors meeting
held in Washington, DC, in June. In July, RERF
scientists continued to provide public lectures toserve citizens who continue to be concerned about
the effects of radiation that may be relevant tothose exposed during the Fukushima accident.
August found RERF scientists working hard to provide an interesting and informative Open House in
Hiroshima and Nagasaki (see cover photo) andmore information about RERF’s public relations
activities is provided by Executive Director Takanobu
Teramoto in Facts and Figures. In response tosuggestions from advisory committees over the last
few years that RERF should review the composition, research focus, and structuring of its basic
science departments of Genetics and Radiobiology/
Molecular Epidemiology (RME), a special international workshop was convened to assist RERF scientists in assessing their future plans and the future
direction of RERF research. The workshop wastitled “Future Plans and Structure for Research in
the Basic Sciences at RERF” and a summary of theworkshop is presented in Conference and Workshop Reports.
Two radiation effects about which RERF scientists have contributed important information over
the years are cataracts and thyroid cancer. Please
read the two Science Articles updating RERF’s
recent findings with respect to those two healtheffects. We received a nice letter of support from
Mr. Kenji Joji (see Letters to the Editors) who
also expressed his sorrow in reading about thedeaths of some of ABCC-RERF’s key leaders. In
Human Interest Notes read more about the serReturn to Table of Contents

Dr. Roy E. Shore (far right) and Dr. Evan B. Douple (far left)
host a visit by Dr. John O. Pastore, his wife, and his granddaughter (center, right to left)

vices held for the late Dr. Itsuzo Shigematsu andabout the recent loss of a dedicated and long-time
RERF pathologist, Dr. Shoji Tokuoka.
It was a pleasant surprise in August when a former ABCC employee, Dr. John O. Pastore stopped
to visit RERF accompanied by his wife and granddaughter. Dr. Pastore was assigned to ABCC as aphysician by the U.S. Public Health Service. He
served two years from 1969–1971 as an epidemiologist and clinician with an interest in cardiovascular disease and stomach cancer. Americans willprobably recognize the name of Dr. Pastore’s father(same name) who served as a distinguished U.S.
Senator from Rhode Island for 26 years. Dr.
Pastore was in Hiroshima as a participant in the20th World Congress of the International Physicians for the Prevention of Nuclear War (see RERF
News). During his tour of RERF, Dr. Pastore recognized that his former office is now an ultrasonography exam room.
The other night a healthy tanuki (raccoondog) family with two “youngsters” stopped by our
kitchen window in Apartment E at Hijiyama Hall(RERF’s housing) as if tosay “What’s for dinner?”—
although they probably had
just finished dining on
Dr. Roy Shore’s composting garden soil. Perhaps A tanuki visiting Hijiyama
they were simply saying Hall“sayonara” after hearing that I will be leaving
Hiroshima in December to retirement and ourhome in Reston, Virginia. Yes—the last five years,
10 issues of Update, and many pleasant memories
have seemed to pass rather quickly. My successor
will find that Maruyama-san has the newsletter ingood shape, but they both of course will welcome
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Letters to the Editors
any feedback and suggestions for improvement thatyou may offer.
Mata oidekudasai (goodbye and please comeagain).

Evan B. Douple
Editor-in-Chief

Fumie Maruyama
Technical Editor

Brenda and Evan Douple exiting a temple gate

The lights of RERF and the sun setting over Miyajima Island
viewed from an apartment in Hijiyama Hall

Letters to the Editors
Dear Maruyama-san,Thank you very much for the recent issue of
RERF Update, which served to bring me up to dateon the developments at RERF, particularly its status as a public interest incorporated foundation in
Japan on April 1, 2012.
Indeed, I have read your In Memoriam with sorrow and sympathy to the bereaved families of passing of Dr. Itsuzo Shigematsu who had the longest
contributory tenure as RERF chairman, Dr. James
Franklin Crow in his significant role in the Scientific Council of RERF and the Crow Committee,
and Mr. Seymour Jablon, who essentially organized the Unified Study Program of ABCC, which
employs among others the Japanese koseki systemin the follow-up of the fixed study population of
RERF.
Their immense contributions to the research
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program and its future are truly immeasurable. Yes,
it was a great pleasure for me to have been able towork with them at ABCC and RERF.
I look forward with great pleasure and expectation to your competent role in the publication of
RERF Update in the years to come.
The initiation of RERF Update by Ms. BethMagura in 1989 is an event of great importance forthe dissemination of the scientific research resultsof RERF for the organization itself and to the public at large. Fortunately, we still maintain congenial
correspondence though a great deal of time has
elapsed since she left her footprints at RERF.
Kindly extend my warmest regards to Dr. Evan
B. Douple.
Gratefully yours,
Kenji Joji
July 14, 2012
RERF Update Volume 23, Issue 2, 2012

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RERF NewsThe Second Board of Councilors Meeting Held in Washington, DC
The second meeting of the Board of Councilors
was held on June 19 and 20 (U.S. time), 2012 at the
National Academy of Sciences in Washington, DC.
All Councilors as well as Directors, Auditors, andone of the co-chairs of the Scientific Advisory
Committee attended the meeting, the first gathering
since RERF made the transition to a public interest
incorporated foundation. Officials of the U.S. andJapanese governments, the U.S. Department ofState, and the National Academy of Sciences participated in the meeting as observers. Following thegreetings by the representatives of both governments, the following items were deliberated.
The activities report, settlement of accounts
report, audit reports, and auxiliary documents were
presented to convey RERF’s operational status for
FY2011, and all were unanimously approved.
As was done last fiscal year, reports were madeconcerning FY2012 activity plans and budgetrelated matters, research projects on A-bomb survivors’ health and on the health of A-bomb survivors’ children, elucidation of individual radiation
doses and the effects from A-bombs, release of
research results and collaboration with other scientific organizations, training programs for domestic
and overseas specialists, and public information
programs, as well as research plans and working
budgets necessary to conduct the projects and programs mentioned above. In addition, measures tocope with further unexpected appreciation of theyen were reviewed, and this year RERF’s futureplans and contributions related to the incident at the
Fukushima Dai-ichi nuclear power plant were
given special notice.
Dr. Sally A. Amundson, Co-chair of the Scientific Advisory Committee, reported that the committee conducted extensive reviews on the activities of the Departments of Radiobiology/Molecular
Epidemiology and Genetics at its meeting heldon March 5–7 at the Hiroshima Laboratory.
She explained that three general recommendations (research prioritization, support activities
for Fukushima, and preservation of biologicalsamples) and other specific recommendations were
made, after which RERF’s responses to these recommendations were discussed.
Concerning procedures of the Board of Councilors, qualification requirements and appointment
procedures of the Councilors, Directors, Auditors,
Scientific Advisors, and Local Advisors were confirmed, and for smooth operation of the board,establishment of the Rules of Procedure of theBoard of Councilors was discussed.
As for official actions related to directors andother officials, two Auditors and Dr. Michael N.
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Cornforth, Scientific Advisor, were reappointed.
Dr. Yoichi Gondo (RIKEN) was appointed as Scientific Advisor to replace Dr. Katsushi Tokunaga.
List of Participants
Councilors:
Mr. Masaaki Kuniyasu, Former Ambassador
Extraordinary and Plenipotentiary to the Republic of Portugal
Dr. Yasuhito Sasaki, Executive Director, Japan
Radioisotope Association
Dr. Hiroo Dohy, Director, Japanese Red Cross
Chugoku-Shikoku Block Blood Center
Dr. Ohtsura Niwa, Professor Emeritus, Kyoto University
Dr. James D. Cox, Former Head, Department ofRadiation Oncology, The University of Texas
M.D. Anderson Cancer Center
Dr. Shelley A. Hearne, Managing Director, Pew
Health Group, The Pew Charitable Trusts
Dr. Jonathan M. Samet, Professor and Flora L.
Thornton Chair, Department of Preventive
Medicine, Keck School of Medicine; andDirector, Institute for Global Health, Universityof Southern California
Mr. James W. Ziglar, Senior Counsel, Van Ness
Feldman; and Senior Fellow and Advisor to theBoard, Migration Policy Institute (Former Sergeant at Arms of the United States Senate)
Directors:
Dr. Toshiteru Okubo, Chairman/Representative
DirectorDr. Roy E. Shore, Vice Chairman and Executive
Director
Mr. Takanobu Teramoto, Executive Director
Auditors:
Mr. Takashi Kohno, Hiroshima General Law/Accounting Office (Hiroshima CPA Cooperative
Office/A&A Tax Accountant Corporation)
Mr. David Williams, Senior Financial Advisor,
National Academy of Sciences
Co-chairperson of Scientific Advisory Committee:
Dr. Sally A. Amundson, Associate Professor of
Radiation Oncology, Center for RadiologicalResearch, Columbia University Medical Center
Representatives of Supporting Agencies:
Mr. Takeshi Sakakibara, Director, A-Bomb Survivor Support Office, General Affairs Division,
Health Service Bureau, Ministry of Health,
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RERF News
Labour and Welfare (MHLW)
Dr. Ryo Takagi, Deputy Director, A-Bomb Survivor Support Office, General Affairs Division,
Health Service Bureau, MHLW
Mr. Glenn S. Podonsky, Chief Health, Safety andSecurity Officer, Office of Health, Safety andSecurity, U.S. Department of Energy (DOE)
Dr. Patricia R. Worthington, Director, Office of
Health and Safety, Office of Health, Safety andSecurity, DOE
Dr. Joseph F. Weiss, Japan Program Manager,
Office of Domestic and International HealthStudies, Office of Health, Safety and Security,
DOE
Mr. Jordan G. Heiber, Office of Japanese Affairs,
U.S. Department of State
Dr. Warren R. Muir, Executive Director, Division
on Earth and Life Studies, National ResearchCouncil (NRC), U.S. National Academy of Sciences (NAS)
Dr. Gregory H. Symmes, Deputy Executive Director, Division on Earth and Life Studies, NRC,NAS
Dr. Kevin D. Crowley, Director, Nuclear and Radiation Studies Board, Division on Earth and Life
Studies, NRC, NAS
Ms. Laura Llanos, Financial & Administrative
Associate, Nuclear and Radiation Studies Board,
Division on Earth and Life Studies, NRC, NAS
RERF:
Dr. Evan B. Douple, Associate Chief of Research
Mr. Eiji Akimoto, Chief of Secretariat
Mr. Douglas C. Solvie, Associate Chief of Secretariat

Participants of the second meeting of the Board of Councilors in front of the National Academy of Sciences

Local Liaison Council Meetings Held in Hiroshima and Nagasaki
The 18th meeting of the Hiroshima Local Liaison Council (HLLC) was held at the Hiroshima
Laboratory on September 13, 2012. Of the 15
council members, 13 (including proxies) attended
the meeting, which was chaired by HLLC chairman
Dr. Toshimasa Asahara (President of Hiroshima
University). To begin the meeting, RERF Chairman
Toshiteru Okubo briefed the participants on thepositioning of the council at RERF as the foundation completed its transition to a public interest
incorporated foundation, and asked the council for
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its continued guidance in terms of RERF’s operations. After greetings by HLLC chairman Asahara,
the meeting’s proceedings started with RERF’s
general report on progress made during the past
year, including the formulation of RERF’s Future
Plans 2012, which contains a plan to establish
a Biosample Center (tentative name), and assistance provided to the health management survey
conducted by Fukushima Medical University. The
summation was followed by reports on recent
research activities and results, the clinical study of
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RERF News
second-generation A-bomb survivors, the status ofcollaborative study with the U.S. National Instituteof Allergy and Infectious Diseases (NIAID), andthe foundation’s public-relations activities. Council
members made comments in response to the planfor centralized management of biosamples, and
HLLC Chairman Asahara expressed his idea toinitiate discussions with RERF on biosample data
sharing in light of the importance of promptly feeding back RERF’s research results to the A-bomb
survivors.
The 21st meeting of the Nagasaki Local Liaison
Council (NLLC) was held at the Nagasaki Laboratory on October 11, 2012, and 17 (including proxies) out of 20 council members participated. After
Dr. Okubo’s greetings, the session’s proceedings
got underway, with Dr. Shigeru Katamine, NLLC
chairman and President of Nagasaki University,presiding over the meeting. RERF’s representatives
made the same reports at the meeting that they did
in Hiroshima on the foundation’s present status andrecent progress. Questions were asked, opinions
actively exchanged, and valuable comments madeconcerning the plan to establish the biosample cen-ter, the data that RERF possesses, and the clinicalfollow-up study of the second-generation A-bomb
survivors. Lastly, Dr. Katamine requested RERF to
fully consider the discussions made at the meetingand incorporate them in RERF’s operations, whilereferring to NLLC’s role in collecting and conveying requests from the local community so that they
are incorporated into RERF’s activities. With this,the 21st meeting of the Nagasaki Local Liaison
Council concluded.

The 18th Hiroshima Local Liaison Council meeting

Chairman Toshiteru Okubo Takes Office as HICARE President
On June 21, 2012, Chairman Toshiteru Okubo
assumed office as President of the Hiroshima International Council for Health Care of the Radiationexposed (HICARE). He succeeded Dr. Shizuteru
Usui (President of the Hiroshima Prefectural Medical Association), who passed away on May 9. The
term of office is two years. Dr. Okubo had served
as Director of HICARE for seven years since heassumed the chairmanship of RERF in July 2005.
Prompted mainly by the Chernobyl nuclear
power plant accident, HICARE was established in1991. The late Dr. Itsuzo Shigematsu, then RERF
Chairman, was the first President of HICARE.
HICARE is jointly operated by Hiroshima University (Faculty of Medicine, Hospital, and ResearchInstitute for Radiation Biology and Medicine),
the Hiroshima Atomic Bomb Casualty Council,
Hiroshima Red Cross Hospital & Atomic-bomb
Survivors Hospital, Hiroshima A-bomb Survivors
Relief Foundation, and RERF among others, withsupport from Hiroshima Prefecture, Hiroshima

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City, the Hiroshima Prefectural Medical Association, and Hiroshima City Medical Association.
HICARE is actively involved in a wide range ofinternational collaborations. Among such activities
are conveying of Hiroshima’s accumulated knowledge about medical care for the radiation-exposedby accepting overseas medical personnel for training in medical treatment of the radiation-exposed,
sending of medical specialists from Hiroshima todifferent regions throughout the world, and organizing lecture meetings and publishing manuals
describing medical treatment of the A-bomb survivors. As for domestic activities, HICARE dispatched specialists to affected areas at the time of
the criticality accident in Tokaimura (Ibaraki prefecture) in 1999 as well as the Fukushima Dai-ichi
nuclear power plant accident in March 2011.
In recognition of its activities, HICARE received
the 48th Health Culture Award in 1996 and both the63rd Chugoku Shimbun Culture Award and theForeign Minister’s Award in 2006.

RERF Update Volume 23, Issue 2, 2012

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RERF NewsThe Second Public Lecture Program for Citizens Held in Nagasaki
RERF held its second public lecture for Nagasaki
citizens at a hall in the Nagasaki A-bomb Museum,from 1:30 to 4:00 in the afternoon of July 21 (Sat.).
This open lecture program for citizens was carriedout for the second time in Nagasaki to promoteexchange between citizens and RERF staff, byproviding intelligible explanations to the generalpublic including A-bomb survivors on RERF’s
longstanding research achievements concerning
A-bomb radiation health effects. Despite the rainy
weather, more than 110 people attended the event.
The public event consisted of two lectures. First,
Dr. Nori Nakamura (Chief Scientist) spoke on“Thinking about low-dose radiation exposure,”
explaining the level of risk increase due to radiation exposure using results from RERF’s longitudinal studies of radiation health effects. Next, Dr.
Asao Noda (Assistant Chief, Department of Genetics) gave a lecture titled “Methods for radiationdose assessment,” introducing basic knowledge ofradiation in a clear and straightforward manner andexplaining that our fear of radiation should beappropriately based on an accurate understandingof radiation and its interactions in people.
At the beginning of the program, following
greetings by Chairman Toshiteru Okubo, Ms.
Sakue Shimohira, former President of the Association of A-bomb Bereaved Families in Nagasaki,

shared her unhappy memories from the ABCC era
as well as her relief about being able to undergo
health examinations since ABCC’s reorganization
into RERF. She also expressed her high expectations for RERF’s continued great success.
Dr. Yuji Nagayama, Director of the Atomic
Bomb Disease Institute (ABDI), Nagasaki University Graduate School of Biomedical Sciences, gave
feedback on the two lectures and made special
remarks about the relationship between ABDI and
RERF. In the Q&A session that followed, manyquestions were raised including those about internal and external exposures associated with thenuclear power plant events in Fukushima.

Second public lecture program for citizens held in Nagasaki

Open House Events in Hiroshima and Nagasaki
RERF held its Open House 2012 events on
August 5 and 6 in Hiroshima and on August 8 and
9 in Nagasaki under the theme “Useful Knowledge
about Radiation and Health Sciences.” They werethe 18th and 16th such events in Hiroshima andNagasaki, respectively.
The Hiroshima Laboratory hosted a special
exhibit on effects of low-dose exposure as well as afeature exhibit titled “Hiroshima and Nagasaki
after the atomic bombings and in recovery” showing photos taken by Dr. Paul Henshaw and documentary footage of Hiroshima recovering from thedevastation. The specialist’s corner next to the special exhibit was visited by many guests who asked
questions about radiation. A lecture commemorating 65 years of ABCC-RERF titled “Radiation
exposure health risks and Fukushima” and one
titled “What is radiation?” were given by Dr.
Toshiteru Okubo, RERF Chairman, and Dr. Norio
Takahashi, a senior research scientist at the DepartReturn to Table of Contents

ment of Radiobiology/Molecular Epidemiology, on
August 5 and 6, respectively. The research departments displayed exhibits introducing their respective studies conducted with the support and coop-

A lecture commemorating 65 years of ABCC-RERF given
by RERF Chairman Toshiteru Okubo for the Hiroshima OpenHouse

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RERF Newseration from A-bomb survivors and many others.
Over the event’s two days, the Hiroshima Laboratory drew 964 visitors eager to listen to the exhibit
explanations and lectures.
In Nagasaki, in addition to the conventional
exhibits showing RERF’s research methods andachievements, this year’s Open House included a
special exhibit in which health risks from low-doseradiation exposure were explained visually withdiagrams, and the same feature exhibit of photographs taken by Dr. Paul Henshaw used in
Hiroshima also were on display. Unlike in typical
years, the hands-on exhibits were not crowded withparticipants this year, making it possible for RERF
staff to devote substantial time to engaging withguests. Over the event’s two days, the Nagasaki
Laboratory drew 326 visitors.

Open House at the Nagasaki Laboratory. Epidemiology
Department Chief Kotaro Ozasa (center) is explaining
radiation health risks to the visitors.

IPPNW Participants Visit RERF
On the morning of August 23, eight participantsin the 20th World Congress of the International
Physicians for the Prevention of Nuclear War(IPPNW) visited RERF Hiroshima Laboratory. The
congress was held on August 24–26 at the International Conference Center Hiroshima. After being
greeted by Chairman Toshiteru Okubo, the visitors
listened to lectures by Dr. Kotaro Ozasa (Chief,
Department of Epidemiology; “Cancer risk ofA-bomb survivors”), Dr. Nori Nakamura (Chief
Scientist; “Genetic effects of A-bomb survivors”),
Dr. Harry M. Cullings (Chief, Department of Statistics; “Dosimetry of A-bomb survivors”), and Dr.
Kazunori Kodama (Chief Scientist; “Radiation
health effects and nuclear abolition”). After the lectures, they were shown panels introducing the history of ABCC and RERF, which Dr. Kazunori
Kodama explained. They then received explanations by Dr. Yoshiaki Kodama (Chief, Departmentof Genetics) about biodosimetry and by Dr.
Yoichiro Kusunoki (Chief, Department of Radiobiology/Molecular Epidemiology) about the mechanistic study of radiation effects in each department.
IPPNW was founded in 1980 with headquarters
in the U.S. state of Massachusetts. IPPNW aims toprevent nuclear war by disseminating accurate
knowledge and information on medical effects

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caused by such conflicts from the perspective ofphysicians with the responsibility to protect people’s lives and health. IPPNW was awarded the1985 Nobel Peace Prize. The IPPNW World Congress this past August was held in Hiroshima for
the first time in 23 years. At the session “Educational Lecture on Health Effects of Radiation,”
which was open to the general public, Vice Chairman Roy E. Shore delivered a talk titled “Healtheffects from radiation exposure” on August 25. At
that lecture session, Dr. Kazunori Kodama served
as co-chair.

Chairman Toshiteru Okubo (far right) briefing the visitorsfrom the IPPNW World Congress

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RERF News

Visiting Scientists
RERF was fortunate to have several former
RERF scientists visiting Hiroshima this fall. Twoformer chiefs of the Statistics Department, Dr.
Dale Preston, Chief Scientist in the HiroSoft International Corporation, and Dr. Donald Pierce, aprofessor in the Oregon Health and Science University, were back at RERF where they were working for a little over two weeks on several projects
including a contract with the U.S. National Cancer
Institute (NCI). Another Department of Statistics
Consultant, Dr. Daniel Stram, another former
RERF statistician and currently a professor in the
Department of Preventive Medicine, University ofSouthern California, also spent a few days and presented a lecture titled “Analysis of cancer risks inpopulations near nuclear facilities: Phase I.”

Déjà vu—Donald Pierce (left) and Dale Preston hard at work
as if it was a previous time at RERF.

Staff News
Three department chiefs reached mandatory
retirement age and were reappointed effective
June 30, 2012; Masazumi Akahoshi, Chief of the
Department of Clinical Studies, Nagasaki, Harry
M. Cullings, Chief of the Department of Statistics,
and Hiroaki Katayama, Chief of the Department of Information Technology. Wan-Ling Hsu,
resigned effective September 10 as an Associate
Senior Scientist in the Department of Statistics.
She moved to Shanghai, China to join her family. Nori Nakamura, a Chief Scientist, resigned
effective December 31 and will be appointed as aConsultant to the Department of Genetics effective
January 1, 2013. Evan B. Douple, Associate Chiefof Research, resigned effective December 31. He
will return to the U.S. where he will retire.
Norio Takahashi’s term as Senior Scientist in
the Department of Radiobiology/Molecular Epidemiology expired on October 31, 2012 and he was
assigned as a Consultant to the Vice Chairman’s
Office effective November 1. Hiromi Sugiyama,
Associate Senior Scientist, was promoted to Acting
Office Chief of the Tumor and Tissue Registry
Office in the Department of Epidemiology as of
October 1. And on a final note, Atsuko Sadakane(MD, PhD) was recruited and appointed as an
Associate Senior Scientist in the Department of
Epidemiology as of October 1. Her research interests are the Life Span Study in RERF and the epidemiology of cancer and noncancer diseases. Her
self-introduction follows.
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Atsuko Sadakane, MD, PhD
I joined the Department of
Epidemiology in Hiroshima asa research scientist on October 1. I graduated from Jichi
Medical University in Tochigi
prefecture in 1999. Jichi Medical University was establishedjointly by Japan’s prefectural Atsuko Sadakane
governments to train physicians who can contribute to improving health andwelfare in medically disadvantaged communities.
Only a few students from each prefecture enter
Jichi Medical University every year. All students
are exempted from tuition costs on the condition
that they work after graduation in medically disadvantaged areas of the prefecture they come fromfor a certain period of time. In keeping with thespirit of establishment of the university, I worked
at a clinic on a remote island and other places inFukuoka prefecture after graduation.
In 2008, after having spent nine years as a clinician, I joined the Department of Public Health at
Jichi Medical University’s Center for Community
Medicine, where I engaged in educational andresearch programs in epidemiology and publichealth. I first set my sights on epidemiologicalresearch because of my involvement in a baseline
investigation for a cohort study immediately after
entering the university, interest in the field generated by an epidemiology class I took in my junior
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RERF News
year of the university, and the fact that the region
where I worked as a physician was being studied aspart of an epidemiological project.
I am honored to have the opportunity to carryout as a research scientist the research mission of
RERF, an organization with a long history andunique character. It will take some time before I am
able to achieve my goal of contributing to RERF’s
future. I want to begin, however, by learning about
the histories of RERF, Hiroshima, and Nagasaki
and understanding RERF’s research achievements.

Reflecting on my situation now, I have had someconnections with Hiroshima in my life. First, mywedding was held in Hiroshima nine years ago.
And second, my husband started working in
Hiroshima three years ago. People at RERF havebeen warm and kind ever since I applied for thisjob. With their help, I have been able to get off to agood start. I would like to get to know everyone at
RERF as soon as possible. I look forward to receiving everyone’s advice and guidance in my research
activities. Thank you in advance for your support.

Awards Received by RERF Scientists
Receiving the 27th Prevention Award of theJapanese Association for Cerebro-cardiovascular Disease Control/Japan Heart
Foundation
Kazunori Kodama, Chief Scientist

On June 15, 2012, at the 48th annual scientificmeeting on cardiovascular disease prevention of
the Japanese Association for Cerebro-cardiovascular Disease Control (JACD) held in Tokyo, I waspresented with the JACD/Japan Heart Foundation’s
Prevention Award.
The award is presented to researchers who havecontributed to the prevention of stroke and heartdisease in Japan, with this year marking the 27thsuch presentation. I was bestowed the honor for mycontribution to the promotion of epidemiologicalresearch on circulatory diseases in Hiroshima andNagasaki and in the NI-HON-SAN study, and forthe education and training of young researchers at
seminars on prevention of circulatory diseases inJapan. This was my second time to receive theaward, my first being the 7th such award in 1992
for epidemiological research on circulatory diseases. I have to believe I received the award thistime for my contribution in particular to the aforementioned seminars on prevention of circulatory
diseases in Japan.
The seminars were initiated in 1988 in the formof a five-day camp, with a view to cultivating
young researchers capable of being active on thefront lines in the field of circulatory disease prevention, and have been held in turns mainly in theregions where circulatory disease prevention studies are conducted. This year marked the 25th seminar, and more than 1,000 physicians, medical students, and allied health professionals haveparticipated to date, with many becoming mainstays in research and activities related to preventionof circulatory diseases in Japan.
I was involved in the 1st through the 20th seminars as a member of its executive committee and in
the 22nd through the 24th seminars as a lecturer.
This means that I participated in 23 seminars out of
the total of 25. I also organized and convened the
5th seminar in Hiroshima. Being the oldest member in the seminar series, I suspect that JACD, ingranting the award to me, had the ulterior motive ofsuggesting that it is about time for me to retire.
Fortunately, younger members have been trained
and are competent and active enough to take over
the reins, and taking this opportunity, I haveannounced my resignation. For everyone’s reference, Dr. Itsuzo Shigematsu was involved in
JACD’s establishment in 1965. I truly wish he wasalive today, as he surely would have been very
pleased to hear this news.

Kazunori Kodama, Chief Scientist, with his award

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RERF Update Volume 23, Issue 2, 2012

RERF News

10

Receiving the Third Hypertension
Research Award
Ikuno Takahashi, Research Scientist
Department of Clinical Studies, Hiroshima

At the 35th annual scientific meeting of theJapanese Society of Hypertension (JSH), held in
Nagoya during the period September 20–22, 2012,
I was presented with the third Hypertension
Research Award. The award was established by the
JSH in 2010 to honor researchers who have published papers in the JSH’s journal Hypertension
Research during the past one year and contributed
to hypertension research and the Society’s development and advancement.
My award-winning paper was selected fromamong papers published in Hypertension Research
between April 2011 and March 2012. Titled “Lifetime risk of stroke and impact of hypertension: Estimates from the Adult Health Study in Hiroshima
and Nagasaki” (Hypertens Res 2011; 34:649–54),
the paper examined the risk of stroke and reported
on long-term effects of hypertension on stroke risk
based on RERF’s Adult Health Study (AHS).
Determining the level of long-term contributionof certain risk factors (e.g., hypertension) to thedevelopment of diseases such as stroke serves asimportant evidence in decision-making related totherapeutic strategies regarding such issues as what
conditions should be treated how aggressively forwhat types of people in order to prevent serious
diseases. However, this kind of evidence wasnearly nonexistent before the paper was published.
This probably explains why my paper has received
such recognition.
Since I joined RERF in Hiroshima six years
ago, I have been investigating effects of radiation
exposure on stroke incidence, and reported the possibility of differences in radiation effects by stroke
subtype starting with the recent paper that won theaward. The study also has led to other studies that I
am now conducting of arteriosclerosis and circulatory diseases. The paper that marked the beginningof my present research could not have received
the award, however, without the cooperation of
the AHS participants as well as support from thestaff of the Departments of Clinical Studies in
Hiroshima and Nagasaki, Statistics, Epidemiology, and Information Technology, as well as manyothers, and for that I am truly grateful to them. I
also received generous guidance and support in
conducting the study and writing the manuscriptfrom Dr. Saeko Fujiwara, chief of the Departmentof Clinical Studies when the manuscript was written, and Dr. Masayasu Matsumoto, professor at theHiroshima University Department of Clinical Neuroscience and Therapeutics. I would like to take
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Ikuno Takahashi, Research Scientist, with her award

this opportunity to express my sincere appreciation
to all of them.
I am determined to push ahead in order toachieve the goals of assessing radiation risk of circulatory diseases and elucidating mechanism(s)underlying the development of such disease. With
that in mind, I look to you all for your continued
guidance and encouragement.
(Editor’s note: A summary of Dr. Takahashi’saward-winning article appears in the Science Articles section of Volume 22, Issue 2, 2011, of RERF
Update.)Upon Receiving Encouragement Award for
Medical Research from the Japan
Medical Association
Waka Ohishi, Acting Chief
Department of Clinical Studies, Hiroshima

I recently received the 2012 Encouragement
Award for Medical Research at the 65th Anniversary Convention of the Japan Medical Association(JMA) held at the Nihon Ishi Kaikan in Tokyo on
November 1, 2012. This award is presented to a
researcher younger than 50 years of age conducting promising medical research, and my awardwinning research theme was “Identification of
biomarkers contributing to risk for hepatocellular
carcinoma development and the biomarkers’ usefulness.”
I was hired by the Radiation Effects Research
Foundation (RERF) in 2004, and what paved theway to my career here was the joint research project “A nested case-control study of hepatocellular
carcinoma among atomic-bomb survivors using
stored sera” initiated by Dr. Saeko Fujiwara, forRERF Update Volume 23, Issue 2, 2012

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Conference and Workshop Reports
mer chief of the Clinical Studies Department, and
Dr. Kazuaki Chayama, professor of gastroenterology and metabolism and Director of Hiroshima
University Hospital. Right away, I was moved tolearn that the sera obtained from the people whohave participated in our Adult Health Study overso many years had been stored since 1969, and at
the same time I started thinking daily on a trialand-error basis about methods regarding how suchvaluable serum samples could be utilized. Fortunately, thanks to the full support I received from thestaff of the Clinical Laboratories Division, I wasable to prepare a protocol on use of the stored sera
based on compiled materials related to serum storage methods and thereby proceed smoothly withreview of the fundamentals of the process.
I first reported in J Clin Microbiol (44:4593–5,
2006) that use of stored sera would not be a problem for detection of hepatitis virus, and I also
reviewed the possibility of using such sera in termsof other examination items (total protein, totalcholesterol, fibrosis marker, C-reactive protein,etc.). Based on these specific reviews, I reported inCancer Epidemiol Biomarkers Prev (17:846–54,
2008) and Hepatology (53:1237–45, 2011) that
hepatitis B virus (HBV) and hepatitis C virus(HCV) infections, alcohol consumption of morethan 40 g per day, obesity with a body mass index(BMI) of 25 kg/m2 or more, and radiation exposure
were all independent risk factors for hepatocellular
carcinoma.
I believe I was presented with the aforementioned award for my series of past studies andongoing project on biomarkers involved in the riskof hepatocellular carcinoma. I would like to takethis opportunity to sincerely thank Drs. Saeko

Fujiwara, John Cologne, Gen Suzuki, and Kazuaki
Chayama for their guidance and cooperation in initiating the research using the valuable stored sera,
which represent very important assets for RERF;
the staff of the Departments of Clinical Studies andEpidemiology in both Hiroshima and Nagasaki, as
well as Hiroshima’s Departments of Statistics andInformation Technology, for their comprehensive
support; and the staff of the Departments of Genetics and Radiobiology/Molecular Epidemiology for
their generous technical advice. Finally, I would
like to conclude this article by expressing heartfelt
gratitude to Chairman Toshiteru Okubo for providing me with the chance to apply for this prestigious
award, and by asking for everyone’s continued
guidance and support.

Waka Ohishi, Acting Department Chief, with her award

Future Plans and Structure for Research in the Basic Sciences at RERF
A Summary of a Workshop Held at
the Radiation Effects Research Foundation, March 8, 2012
Evan B. Douple, Associate Chief of Research
Roy E. Shore, Vice Chairman
During the past few years, RERF’s scientificadvisory bodies have pointed out that the departmental structure of RERF’s basic science research,
primarily the Department of Genetics and theDepartment of Radiobiology/Molecular Epidemiology (RME), have not changed for quite sometime. They encouraged RERF to assess the effectiveness of the current structuring, appraise andprioritize the current major areas of research, andReturn to Table of Contents

identify areas of expertise where future recruitments of younger scientists might have a significant and immediate impact on the research themesof RERF. Seven researchers distinguished in theareas of genetics, radiobiology, and molecular epidemiology research were invited to participate in a
half-day workshop to assist RERF scientists intheir review of the RERF basic science research.
The workshop was divided into five sessions. The
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Conference and Workshop Reports
sessions are described below and the session moderators are identified in parentheses. Fourteen
major recommendations are numbered and summarized in bold.

I. Introduction, Goals, and Charge (Toshiteru
Okubo/Roy E. Shore)
The RERF Chairman and Vice Chairman asked
participants to think about the future of RERF
basic science research, specifically with respect tothe two departments of Genetics and RME. This isespecially important since: (a) RERF has beenrequested to develop long-term future plans; (b) asignificant number of research scientists are reaching or have reached retirement age; and (c) tightbudgets require that we prioritize what recruitments should be conducted and what basic science
research should and could be done within the context of our mission and the interests of the supporting governments. Other key questions raised
included: (d) Should RERF continue to have two
separate departments with the current structure? (e)How competitive is RERF research in a global
sense?, and (f) What and how can we do better thanothers?
The RERF Chairman concluded his remarks bypointing out that answers to the above questions
and critical judgments are difficult to make within
the organization so RERF appreciates having theoutside advice and perspectives that the participants brought to this workshop.
II. Future of the Genetics Department: Perspectives and Plans (Katsushi Tokunaga/
John J. Mulvihill)
The Chief of the Genetics Department, Dr.
Yoshiaki Kodama, summarized the department’s
future plans, key recruitment and facility needs,
and thoughts regarding department reorganization.
The focus of research proposed included: (a) Estimation of the genetic effects of A-bomb radiationin humans using the whole-genome sequencingbased approach; (b) Use of the green fluorescentprotein (GFP) mouse model to study somatic andgermline mutations in situ; and (c) Development of
new methods for biological dosimetry (flow-fluorescence in situ hybridization [FISH]). With respect
to recruitment needs, Dr. Y. Kodama recommended
and prioritized three desired recruitments: (a) A
bioinformatician to assist with the design, interpretation, and analyses of experiments; (b) A young
scientist with animal model experience; and (c) A
young scientist with an interest in biodosimetry
and molecular biology. With respect to facilities
that would assist the department research scientists
in meeting their goals, Dr. Y. Kodama cited a nextgeneration sequencer five years from now, an
improved animal facility as soon as possible, and a
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12state-of-the-art flow cytometer. With respect to thedepartment members’ reaction to the proposed
options for departmental reorganization, the department members supported investigating some formof restructuring of the two departments and recruitment of a department chief.
1. Understanding the effect of radiation on
the human genome remains an important
challenge and RERF has precious biosamples to help mankind learn how sensitive
the genome is to radiation and how muchgenomic variation affects the transport ofradiation risk from RERF to other populations.
2. While RERF should consider the use ofnext-generation whole genome sequencing, it is expensive, requires high-levelbioinformatics expertise for interpretationof results, might not be able to resolve key
questions related to mechanisms of mutation and other radiation effects, and may
have to involve collaborations and outsourcing external to RERF; planning aninternational workshop might be considered to provide assistance and advice inthis issue.
3. Developing new biodosimetric techniquessuch as flow-FISH is interesting, but might
not be the best use of RERF resources;
however, it is to RERF’s advantage tomaintain cytogenetic capability because of
potential societal needs.
4. The model in which mutant cells become
green because of expression of GFP isespecially interesting and should be
expanded to include in vitro irradiation
studies which correlate with the GFP
mouse data.

III. Future of the RME Department: Perspectives and Plans (Sally A. Amundson/
Kazuo Sakai)
The session was opened with a statement by
the Chief of the RME Department, Dr. Yoichiro
Kusunoki, who summarized the department’s
future plans, key recruitment and facility needs,
and thoughts regarding department reorganization.
The focus of research proposed included: (a) Risk
assessments of radiation- and aging-related diseases; (b) Mechanistic studies of radiation-induced
carcinogenesis; and (c) Mechanistic studies of radiation-associated noncancer diseases. With respect
to recruitment needs, Dr. Kusunoki recommended
and prioritized two desired recruitments—a midcareer scientist with expertise in new analyticaltechnologies who would be qualified to take leadership in the Cell Biology Laboratory and a young
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Conference and Workshop Reports
scientist with immunology training and researchinterests. With respect to facilities that would
assist the department research scientists in meeting
their goals, Dr. Kusunoki cited a next-generation
sequencer five years from now, an improved animal
facility as soon as possible, and a state-of-the-art
flow cytometer. The latter equipment could be usedin combination with mass spectrometry to facilitate the measurement of protein expression levels
and studies of proteomics and metabolomics, andcould be used in RERF’s studies of epigenetics.
With respect to the department members’ reaction to options for departmental reorganization,
the department members supported an attempt to
restructure the two departments.
5. Studies of methylation and epigenetic
effects represent important topics for
RERF research, but clearly defined
hypotheses need to be articulated for thosestudies to be productive and meaningful.
6. RERF scientists working on using archival
tissues for cancer studies were encouraged
to collaborate with Dr. M. Atkinson’sgroup in Germany who have been extracting DNA from archival tissues.
7. The studies of the involvement of specificchromosomal translocations such as with
RET and ALK genes are important since
they may explain individual differences inradiation susceptibility.

IV. Basic Science Restructuring Options(Evan B. Douple/Kazunori Kodama)
Dr. Evan Douple discussed various considerations regarding restructuring the basic science
departments. He pointed out that the three key
ingredients that require decisions to be made andwhich rely on each other are: (a) Plans for future
research directions; (b) Recruitment of new scientists to carry out those plans; and (c) Restructuringof departments to optimize shared resources,
expertise, and new ideas. He pointed out that RERF
scientists have been requested to prepare longrange plans for the foundation and it will be necessary to decide whether and how many scientists
should be recruited to fill future anticipated vacancies, and whether certain projects can be done at
RERF or whether it is more effective to outsource
certain tasks and establish collaborations with scientists outside RERF. Of course another alternative
is to continue current research activities and essentially proceed as the status quo.
With respect to recruitment, Dr. Douple raised
the following questions:a. What kind of scientists should we recruit(young, mid-career, or established)?
b. Do we have the appropriate department
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13
structure to provide younger scientists withrequisite mentorship?
c. Do we know what we want the scientists tobe able to do?
d. How best can we get the message out that
RERF is recruiting scientists?
e. Are there qualified candidates who might beinterested in RERF and available?
f. Can we successfully recruit highly qualified
candidates to come to RERF?
The session concluded with a discussion focusedon five restructuring scenarios. It was generally
agreed that RERF should not take the option todissolve the Genetics Department. RERF needs
genetic expertise, geneticists need to resolve theradiation mutation risk in humans, the A-bomb
dosimetry may benefit some from cytogenetic
studies and electron spin resonance (ESR) tooth
dosimetry, and despite a large percentage of scientists who have reached retirement age a core willremain who are working on promising projects.
With respect to the option to restructure Genetics
and RME, one possible change would be to update
the names of the laboratories.
8. Both basic science research departments
at RERF would benefit from an improved
animal facility since mouse studies areimportant to bridge the epidemiologic
findings to basic biology and humans.
9. It was suggested that departmental laboratory delineations, if retained, be
renamed with more up-to-date terminology (cytogeneticscellular genetics; biochemical geneticsmolecular genetics;
immunologyradiation immunobiology;
cell biology molecular oncology ormolecular epidemiology.
10. If the two basic science departments weremerged, it would encourage collaboration and sharing of new technologies,
possibly lead to more cutting-edge
research, and could include working
groups with the potential to promote
cross-fertilization and creativity; such amerger might be called Department ofRadiation Biology and Genomics.
11. Final administrative decisions regarding
retention of the existing departments or
restructuring should depend on the prioritization of the future research andrecruitment plans.

V. General Discussion and Recommendations
Regarding Future Directions and Structure(Kiyoshi Miyagawa/William F. Morgan)
A. Future Directions: It was stated that basic
sciences will become more important in the future,
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Conference and Workshop Reports
because clinical and epidemiological studies will
be reduced due to the deceased cohort. It wasemphasized that the primary research issues forbasic science research are to provide a bridge to the
Epidemiology, Clinical Studies, and Statistics
Departments, so that the epidemiologic study
results regarding radiation risk can be better understood biologically. For example, an important issue
is: What is the biological basis as to why exposure
at younger ages gives a higher risk for some tissues
but not for others? Another example is that it isimportant to bring basic studies to bear on how to
reduce the confidence intervals (i.e., increase theprecision of knowledge) regarding low-dose radiation risk. This requires mutual feedback and ideas
among scientists. A third example is that the understanding about chromosome rearrangements inradiogenic thyroid cancer may provide an avenue
for better understanding the effect. It was generally
agreed that four major issues RERF scientists
should and could address further were: age dependency, cancer-site specificity, effects at low doses/
dose-rates, and transgenerational risk.
B. Communication Network: RERF should
be more aware of and responsive to the needs ofradiation science by developing as much discussion
as possible with the outside radiation community.
RERF scientists should look for opportunities forpresenting their data to additional potential sourcesof funding including various divisions of the U.S.
National Institutes of Health.
C. Recruitment: It was opined that scientificsocieties of molecular biology, human genetics,
and bioinformatics know virtually nothing about
the past/present research and research opportunities at RERF. Developing contacts and advertising
positions in those venues would be valuable. However, RERF was cautioned to be realistic about
funding and future recruitments and not aim forsomething we cannot achieve. It was suggested that
RERF make a prioritized “wish list” of researchareas in which we would like to recruit and think ofplaces to advertise for those specialties. It was suggested that we try to work out a joint appointment
with a university; this could make the recruitment
package very attractive.
D. Restructuring Options: It was proposedthat RERF consider organizing into two divisions
to gain economies of scale; the two divisions would
be clinical and epidemiological sciences, and laboratory sciences and core facilities. It was suggested
that by combining two basic science departments
RERF might save on administrative staff, but investigators were concerned about this idea because thestaff are already overworked and this could compound the problem. There was some concern about
future directions for cytogenetics and biodosimetry. However, it is important to maintain cytogeReturn to Table of Contents

netic capabilities because of potential societal
need, but obtaining external funding for research inthis area is extremely difficult, thereby making it adifficult career decision for a young researcher. The
workshop’s concluding remark was that centralization of the biosample database is more important
than centralization of collected cells. Comprehensive, accurate tracking of what has been done withgiven samples and what samples are available for
future studies are what are most important.
12. Since there will be multiple RERF
research scientists retiring in the near
future, a recruitment package might bemade more attractive by permitting therecruit to bring a colleague and by providing a joint academic appointment
with a university.
13. Key issues for future RERF radiation
health effects research should include the(a) age dependency, (b) cancer-site specificity, (c) effects of low doses and dose
rates, (d) role of somatic mutations, epigenetics and chromosome rearrangements in radiogenic cancers, (e) why
exposure at younger ages give higher
risks for some tissues but not for others,and (f) the estimation of transgenerational risk.
14. A high priority should be given to theestablishment of a comprehensive, accurate, secure, and readily accessible centralized biosample database that mightalso be administered and monitored in acentralized biosample repository.
Participants
Dr. Sally A. Amundson, Associate Professor of
Radiation Oncology, Center for RadiologicalResearch, Columbia University Medical Center
Dr. Kiyoshi Miyagawa, Professor, Laboratory of
Molecular Radiology, Center for Disease Biology and Medicine, Graduate School of Medicine, The University of Tokyo
Dr. William F. Morgan, Director of Radiation
Biology and Biophysics, Biological Sciences
Division, Pacific Northwest National Laboratory
Dr. John J. Mulvihill, Children’s Medical ResearchInstitute/Kimberly V. Talley Chair in Genetics;
Professor of Pediatrics; Head, Section of
Genetics, University of Oklahoma Health Sciences Center
Dr. Tetsuya Ono, Professor, Division of Genome
and Radiation Biology, Department of Cell
Biology, Graduate School of Medicine, Medical Sciences, Tohoku University
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Conference and Workshop Reports
Dr. Kazuo Sakai, Director, Research Center for
Radiation Protection, National Institute ofRadiological Sciences
Dr. Katsushi Tokunaga, Professor, Department of
Human Genetics, Division of International
Health, Graduate School of Medicine, The University of Tokyo
RERF
Dr. Toshiteru Okubo, Chairman/Representative Director

Dr. Roy E. Shore, Vice Chairman and Executive Director
Mr. Takanobu Teramoto, Executive Director
Dr. Evan B. Douple, Associate Chief of Research
Dr. Nori Nakamura, Chief Scientist
Dr. Kazunori Kodama, Chief Scientist
Dr. Yoshiaki Kodama, Chief, Department of Genetics
Dr. Yoichiro Kusunoki, Chief, Department of Radiobiology/Molecular Epidemiology

Participants of the meeting on future plans and structure for research in the basic sciences at RERF

The 35th Meeting of the Japanese Society of Cancer Epidemiology
Kotaro Ozasa, President of the 35th meeting(Chief, Department of Epidemiology)
The 35th meeting of the Japanese Society ofCancer Epidemiology, based on the theme “Radiation and Cancer,” was held on July 5 and 6, 2012, atthe Aster Plaza (Naka-ku, Hiroshima). This society
was established in July 2010 by the merger of theJapanese Society of Cancer Epidemiology and theJapanese Society of Cancer Molecular Epidemiology. The Japanese Society of Cancer Epidemiology
held its inaugural general meeting in 1977, gathering research scientists who played key roles in thefield of cancer epidemiology in Japan. Dr. Hiroo
Kato, RERF, and Dr. Noboru Kurihara, Hiroshima
University, jointly took charge of the 5th meeting,
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which was held in 1982. The 18th meeting washeld in 1995 under the presidency of Dr. Kiyohiko
Mabuchi. On the other hand, the Japanese Societyof Cancer Molecular Epidemiology was established to focus on molecular epidemiology in thefield of cancer epidemiology, with its initial meeting held in 2000. The 4th and 7th meetings were
held with Dr. Kei Nakachi at the helm in 2003 and2006, respectively. Molecular epidemiology thereafter became a universal presence in the field ofcancer epidemiology, and hence the two societies
were merged as mentioned above. The combined
society covers a broad range of fields that employ
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Conference and Workshop Reports
epidemiology and molecular epidemiology withthe aim of cancer prevention/treatment and acquisition of cancer-related information, such as descriptive epidemiology, analytic epidemiology, intervention research, cancer registry, health examination,
molecular epidemiology, pathogenesis, diagnostic
classification, incidence factors, preventive factors,
prognosis factors, cancer management, cancer prevention, patient quality of life (QOL) issues, social
systems, and other research areas.
The recent meeting introduced epidemiological research in Japan regarding radiation-cancer
association from various perspectives with reference to the course of events following last year’s
TEPCO Dai-ichi nuclear power plant accident at
Fukushima, explained principles of perception ofradiation risk and related scientific findings, andoffered an opportunity to review measures to deal
with the current situation in Fukushima from anepidemiological viewpoint, incorporating the program indicated below:
Special lecture: “Major epidemiological studies ofcancer risk and low-dose radiation” (Suminori Akiba, Kagoshima
University)
Symposium: “Current status of radiation cancer
epidemiology with special reference
to low-dose risk”• Epidemiological study of A-bomb survivors
and challenges in low-dose risk assessment(Kotaro Ozasa, RERF)• Mortality follow-up study of nuclear power
plant workers (Fumiyoshi Kasagi, Radiation
Effects Association)• Study of potential radiation risk among residents in the vicinity of nuclear power plants(Yasuhiko Yoshimoto, National Institute ofRadiological Sciences)• Mortality follow-up study of radiology technicians (Shinji Yoshinaga, National Instituteof Radiological Sciences)• Radiation, smoking, and lung cancer (Kyoji
Furukawa, RERF)• Radiation risk of skin cancer among A-bomb
survivors (Hiromi Sugiyama, RERF)
Workshop: “Health management after the Fukushima
Dai-ichi nuclear power plant accident”• Health management of residents in Fukushima
prefecture (Seiji Yasumura, Fukushima Medical University)• Health management of emergency/recovery
workers (Shinji Yoshinaga, National Instituteof Radiological Sciences)
Symposium: “Radiation and cancer molecular epidemiology”• Molecular epidemiology of radiation-associated cancer (Tomonori Hayashi, RERF)
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16• Study of cancer in relation to gene-environment interaction, and case-cohort design(John B. Cologne, RERF)• Molecular patho-epidemiological study basedon stored solid cancer specimens from
A-bomb survivors (Masahiro Nakashima,
Nagasaki University)• Characteristics of gene mutation in papillary
thyroid cancer among A-bomb survivors(Kiyohiro Hamatani, RERF)• Radiation-induced cancer and chromosome
aberration (Satoshi Tashiro, Hiroshima University)• Genetic effects from radiation among childrenof A-bomb survivors (Jun-ichi Asakawa,
RERF)
Numerous RERF research scientists, symbolizing RERF’s significance in the radiation epidemiology research community in Japan, served as lecturers at the meeting. Seventeen poster presentations
also were made. The society is a small study groupconsisting of about 250 members. Even though thetotal number of participants was at most about 130,
RERF staff members participating in the meeting
numbered around 40.
Since last year, public interest in health effectsof radiation has grown rapidly. Particularly concerning such issues as unsubstantiated low-doseradiation risk and hard-to-assess internal radiation
exposure risk, information from a wide variety ofsources is in general circulation, revealing a major
problem in the area of risk communication. Furthermore, this field of research is still lacking inhuman resources. Consequently, it is hoped that themeeting provided the opportunity for as many
investigators as possible to become interested inwork on issues related to radiation epidemiology.
Lastly, I would like to express my heartfelt
appreciation to Dr. Tomonori Hayashi, AssistantChief of the Department of Radiobiology/Molecular Epidemiology, Dr. Ritsu Sakata, Associate

The 35th meeting of the Japanese Society of Cancer Epidemiology held at Aster Plaza in Hiroshima

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Conference and Workshop Reports
Senior Scientist at the Department of Epidemiology, and the staff of the Secretariat and the Department of Epidemiology for their dedication to thesuccess of the recent meeting. Dr. Hayashi handledlectures/posters relating to molecular epidemiology
and provided advice relating to the program in arole akin to that of the meeting vice-president. Dr.

Hayashi also made such practical arrangements as
selection of the venue. Dr. Sakata worked on thehandling of practical operations for the meeting.
The staff of the Department of Epidemiology andSecretariat worked hard on preparations for the
meeting and practical operations on the days of themeeting.

The Third Epidemiological Training Workshop for Biologists
Nori Nakamura, Chief Scientist
The third Epidemiological Training Workshop
Ozasa).
for Biologists, hosted by the Council of RadiaIn the afternoon, such sessions as “Review oftion Effects Research Organizations, was held
genetic effects of A-bomb radiation” (by Chief ofGenetics Department Yoshiaki Kodama), “DescripAugust 20–21, 2012, at the RERF Auditorium intions of a paper by Lancet (2012) regarding radiaHiroshima. This year’s workshop was attended
tion exposure from CT scans in childhood and subby about 60 people (28 outside participantssequent risk of leukemia and brain tumors” (by Dr.
and 29 RERF staff). (The Council of Radiation
Ozasa), “Review of risk for malignant tumors
Effects Research Organizations, consisting of
among the offspring of A-bomb survivors” (byFukushima Medical University, Hirosaki UniverAssistant Chief of Epidemiology Department Ericsity, Hiroshima University, the Institute for EnviGrant), and “Problem presentation: whether or notronmental Sciences, Kyoto University, Nagasaki
risk to the fetus is higher than that to children” (byUniversity, National Institute of RadiologicalDr. Hiromi Sugiyama, Research Scientist, EpideSciences, and RERF [in alphabetical order], wasmiology Department, and Dr. Nakamura) were
established to develop understanding among radiaheld, followed by a social gathering held outsidetion research organizations and strengthen their
RERF.
alliance.)
The workshop’s second day featured such
Following opening remarks by Chairman
sessions as “Review of cardiovascular diseaseToshiteru Okubo, an explanatory session titledrisk among A-bomb survivors” (by Dr. Ikuno“Basics of radiobiology for non-biologists” (by AsTakahashi, Research Scientist, Clinical Studies andsistant Chief of Genetics Department Asao Noda
Epidemiology Departments), “Problem presentaand Chief Scientist Nori Nakamura) was introtion: what effects of age at exposure mean” (by Dr.
duced to the workshop this year on a trial basis, inNakamura), and “Discussion: whether decreased
response to requests from statisticians and epiderelative risk with increase in number of years after
miologists. The hope was that the sharing of someradiation exposure was caused by chance or necesdegree of knowledge with biologists could enrichsity” (by Dr. Nakamura and Dr. Ohtsura Niwa, Procommunication among the different disciplines.
Also presented werelectures titled “Frombasics of epidemiology to A-bomb radiation effects” (byDr. Ritsu Sakata,
Research Scientist,
Epidemiology Department) and “Abomb survivor Life
Span Study (LSS):
descriptions of LSS
Report 14” (by Chiefof Epidemiology
Department Kotaro
Participants of the third epidemiological training workshop for biologists
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RERF Update Volume 23, Issue 2, 2012

18

Conference and Workshop Reports
fessor Emeritus, Kyoto University). The workshop
on that day concluded at noon.
After experiencing three such workshops held at
RERF, I now understand the challenge of communication among such different fields of research. As
mentioned above, the explanatory session regarding basics of radiobiology for non-radiobiologists
was introduced to the workshop, but a portion ofparticipants commented that the session was too
difficult to totally understand. This issue points tothe possibility that the workshop concept still has
room for improvement. When preparing for the latest workshop, I grasped for the first time the significant difference between epidemiological research
and animal experiments: the former aims at
describing risk changes in small increments overtime until completion of the research, whereas thelatter work focuses for the most part only on lifetime risk (i.e., the percentage of tumor cases devel-

oping in a certain group). Furthermore, animal
experiments sometimes do not involve lifelong
observation (i.e., follow-up until natural death).
Under such circumstances, it is impossible even to
lay the groundwork for discussion about research
into mechanisms behind carcinogenesis in parallelwith the theme of epidemiological research. If an
animal experiment were to try to carry out observations up to the point at which changes occur at thestage of cancer diagnosis, it would be necessary totarget a large population (e.g., a population of atleast 300 mice), making me feel that the current
situation is unavoidable. If sufficient communication among different fields of research had takenplace in the past, conduct of higher-quality animal
experiments might have been possible, even though
it is too late at this point in time, when the numberof currently available animal experiment facilities
is already limited.

The 58th Annual Meeting of the Radiation Research Society(September 30–October 3, 2012) in San Juan, Puerto Rico
Evan B. Douple, Associate Chief of Research
RERF was well represented at the 2012 meetingof the Radiation Research Society held in San Juan,
Puerto Rico. Posters were presented by Evan B.
Douple, Eric J. Grant (Assistant Chief, Epidemiology Department), Kazuo Neriishi (Part-time Professional, Vice Chairman’s Office), and Ritsu
Sakata (Associate Senior Scientist, Epidemiology
Department). In addition, Harry M. Cullings(Chief, Statistics Department) was invited to participate in a symposium on Radiation-induced
Occupational Cancer and Non-cancer Risks: Past,
Present and Future Perspective. His presentation
was titled “Incidence of leukemia, lymphoma, andmultiple myeloma among the Japanese atomicbomb survivors: 1950–2001” (based on the paper
by Wan-Ling Hsu et al.). Dr. Douple was invited topresent a topical review lecture on “Lessons

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learned from RERF and from Fukushima and othernuclear accidents for more effective communication of radiation risks.”

Two of the three RERF posters presented at the Radiation
Research Society meeting in Puerto Rico

RERF Update Volume 23, Issue 2, 2012

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Science Articles

Radiation Dose and Cataract Surgery Incidencein Atomic Bomb Survivors, 1986–2005*
Kazuo Neriishi
Part-time Professional, Vice Chariman’s Office*This article is based on the following publication:
Neriishi K, Nakashima E, Akahoshi M, Hida A, Grant EJ, Masunari N, Funamoto S, Minamoto
A, Fujiwara S, Shore RE. Radiation dose and cataract surgery incidence in atomic bomb survivors, 1986–2005. Radiology 265:167–74, 2012 (doi:10.1148/radiol.12111947)

Introduction
Since the 1950s, the prevailing view had beenthat only relatively high doses of at least several
gray (Gy) induce vision-impairing cataracts,1 e.g.,
the International Commission on Radiological Protection (ICRP) judged that a brief exposure of atleast 5 Gy was required or an even larger cumulative dose of protracted or fractionated radiation.2,3
Several studies in the last couple of decades had
found that radiation doses under 1 Gy were associated with primarily low-grade opacities that havelittle effect on visual acuity, but virtually no data
were available on radiation and clinically significant cataracts. In 2007 we published data on radiation dose and the prevalence of cataract surgery ina subset of the Adult Health Study (AHS) cohort,showing a dose response with an estimated 39%
excess relative risk at 1 Gy and no clear evidence
for a dose threshold, albeit the data also were compatible with a dose threshold of up to 0.8 Gy.4 That
study played a large role in the recent revision of
the ICRP guidelines indicating that eye lens doses
should be limited to <0.5 Gy, a 10-fold reduction in
the dose limit.5
However, cross-sectional prevalence studies
have certain methodological limitations that may
produce biased risk estimates; furthermore thesample size of the prevalence study was fairly
small, so we believed that a longitudinal incidence
study of cataract surgery was needed. That led tothe present study which compiled the frequency of
incident cataract surgery (i.e., an individual’s firstcataract surgery) among the 6,066 eligible participants in the AHS during the time period 1986–
2005.
The three main objectives of the current study
were: (a) to quantify the degree of cataract surgery
risk from radiation, adjusting for other cataract risk
variables that might be confounders; (b) to determine whether the dose-response association isapproximately linear or has upward curvature; and(c) to estimate the dose-effect threshold level. The
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current study examines the incidence of clinicallyimportant cataracts in relation to lens doses
between 0 and approximately 3 Gy to address risks
at relatively low brief radiation doses.

Materials and Methods
Materials
Since 1958, the AHS has conducted biennial
clinical health examinations of individuals exposedto the atomic bomb (A-bomb).6 Beginning in 1986,
cataract surgery, as confirmed by using ophthalmoscopic examination, was systematically recorded in
the medical charts. For the current study, chart
reviews of all study subjects were conducted byexperienced physicians to assure accurate codingof cataracts. Incident cases of surgically removed
cataracts (i.e., their first cataract surgery) among
AHS subjects were identified during 1986 through2005. For dose-response analyses, we used the eyeradiation absorbed dose in Gy, which is the sum of
the gamma dose plus 10 times the neutron dose
based on the current Dosimetry System 20027 andadjusted for dose measurement error.8 Sixteen lens
opacity risk factors were identified from the literature9–12 for which questionnaire or observational
information was available, including the following:education; marital status; history of smoking; bodymass index; systolic and diastolic blood pressure;platelet count; lactic acid dehydrogenase level; uricacid level; γ-glutamyltransferase level; history of
diabetes mellitus, hypercholesterolemia, hypertension, angina pectoris, or myocardial infarction; andcorticosteroid medication use. Between 1986 and2005, 8,055 individuals visited the AHS clinics
more than once, so that new incident cases could be
identified (at the initial visit during that period,
prevalent cases were identified, while at subsequent
visits, new, incident cases of cataract surgery wereidentified), but some were inappropriate for inclusion: 1,861 individuals who were prenatally exposed
or whose radiation doses were unknown, 122 individuals who underwent cataract surgery before
RERF Update Volume 23, Issue 2, 2012

20

Science Articles
January 1986, and six individuals in whom the dateof surgery was unknown. That left 6,066 eligible
individuals (without a prior cataract surgery) who
were considered at risk beginning at their first AHS
clinic attendance date after January 1, 1986, until
cataract surgery was performed, the last date ofattendance at the AHS clinic, or December 31,
2005, whichever occurred first.
Statistical methods
The first phase of the analysis consisted of an
examination of the 16 identified cataract risk factors to determine which were potential confoundervariables by using Cox regression.13 The basic variables for the risk factor analysis also included thedemographic variables of city, sex, age at exposure,and attained age, plus eye radiation dose. These
were analyzed in a multivariate model adjusted
simultaneously for all the other risk factors. The
analyses suggested that the only risk-factor variable that might be a confounder was diabetes mellitus, so it was adjusted for in the radiation-risk
models.
In the second phase to assess radiation risk,
excess incidence was modeled as both excess relative risk (ERR) at 1 Gy and excess absolute risk
(EAR) expressed per 10,000 persons per year at 1
Gy by using the Amfit program in the Epicure statistical package14 to perform Poisson regression ofgrouped data. Poisson regression allows the risk to
be partitioned into background risk, dose effects,
and dose-effect modifiers. For the analysis, theperson-year data were simultaneously stratified
according to city, sex, diabetes mellitus, age at
exposure, attained age, time since exposure, andeye radiation dose (≤0.005, 0.005–, 0.03–, 0.1–,
0.2–, 0.4–, 0.6–, 0.8–, 1.0–, 2.0–3.0, >3.0 Gy). Diabetes mellitus status was coded as positive for adiabetes diagnosis prior to lens surgery or at any
time during an individual’s follow-up if there wasno surgery. Both ERR and EAR models were fitted,
including city, sex, diabetes mellitus, age at exposure, and either attained age or time since exposure(TSE) to model background risk and as potential
radiation dose-effect modifiers. Because TSE is amore natural way of describing radiation risk thanis attained age, unless the attained-age model fits
the data appreciably better than the TSE model, theTSE model was chosen. In both the ERR and EAR
models, the eye dose term was modeled both as
linear and linear-quadratic to better assess lowdose risk levels. Both the two-sided significancetests and 95% confidence intervals (CI) were basedon likelihood ratio tests applied to the profile likelihood.15 The magnitude of the dose-response threshold level was estimated on the basis of the optimalmodel from the radiation-risk analysis.

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Results
Population description
There were 1,028 persons with initial cataract
surgery between 1986 and 2005 among the 6,066
study subjects who contributed 84,209 personyears. Table 1 shows the numbers of cataract surgery cases and person-years according to eye radiation dose, sex, city, and age at exposure. The
cumulative incidence of cataract surgery was similar in the two cities, but the crude cumulative incidence of cataract was higher in females (18.5%,
745 of 4,035) than in males (13.9%, 283 of 2,031).
The mean age at exposure was 20.4 years (range,
0–54 years). For both sexes, the mean age at cataract extraction was 74.4 years, and the range was
49–95 years. The mean lens dose across all study
subjects was 0.50 Gy (range, 0.0–5.14 Gy).
Table 1. Person-years (PY), cataract surgery cases,
and crude incidence rates per 10,000 PY by
DS02 eye dose categories, city, gender, andage at exposure
Person-years
(PY)

Cases

Rate per10,000 PY

28,097
56,112

283
745

101
133

53,72430,485

646
382

120
125

GenderMale
FemaleCity
Hiroshima
NagasakiAge at exposure (y)
<10
10–
20–
≥30
Dose (Gy)<0.0050.005–
0.4–
1.0–
2.0–
≥3.0

16,26737,404
19,45811,081

66
412
350
200

41
110
180
180

35,821
19,101
14,345
10,328
2,764
1,849

386
234
182
148
43
35

108
123
127
143
156
189

Total

84,2091,028

122

Risk factor analysis for potential confounding
variables
Table 2 shows the distribution of cataract risk
factors and the Cox hazard ratios (HRs) for dose,the basic demographic adjustment variables, andthe most relevant covariates. The HRs are shown
while simultaneously adjusting for all 16 potential
risk factors by using multivariate analysis. Significant risk variables in the multivariate analysis werediabetes mellitus, angina pectoris, no college education, and a high body mass index. However,adjustment for all the covariates simultaneously
had almost no effect on the radiation risk, indicating they were not material confounders. SpecifiRERF Update Volume 23, Issue 2, 2012

21

Science Articles
Table 2. Cox regression hazard ratios (HR) and 95%
confidence intervals (CI) for demographic
factors, radiation dose, and cataract surgery
risk factors
Covariate

Cataractcases/Total
subjects

City
Hiroshima
646/3,985
Nagasaki382/2,081
GenderMale
283/2,031
Female745/4,035
Age at exposure (y)0–<10
66/ 967
10–<20412/2,376
20–<30350/1,459≥30
200/1,264
DS02 eye dose (Gy)
0–<0.005
386/2,530
0.005–<0.4
234/1,402
0.4–<1.0
182/1,027
1.0–<2.0
148/ 750
2.0–<3.0
43/ 212≥3.0
35/ 145
Education
Junior high§434/2,646
High school
529/2,854
College65/ 566
Smoking
Never§
686/3,774
Ex-smoker
173/ 956
Current
169/1,336
Body mass index (kg/m2)<20§
244/1,624
20–<25554/3,190
25–<30210/1,123≥30
20/ 129
Diabetes mellitus
No891/5,478
Yes137/ 588
Hypercholesterolemia
No§949/5,713
Yes
79/ 353
Hypertension
No572/3,484
Yes
456/2,582
Angina pectoris
No
960/5,762
Yes
68/ 304
Myocardial infarction
No1,020/6,002
Yes
8/ 64
Oral/Injected corticosteroids
No§1,003/5,944
Yes
25/ 122

Adjusted
analyses†
HR

CI

1
1.19

–
1.03, 1.36

1
1.16

–
0.96, 1.41

1‡
2.68
4.99
7.64

–
2.08, 3.52
3.81, 6.63
5.67, 10.4

1‡
1.10
1.15
1.37
1.92
2.19

–
0.93, 1.30
0.96, 1.37
1.13, 1.65
1.38, 2.60
1.52, 3.06

1
1.08
0.76

–
0.94, 1.23
0.57, 0.98

1
1.20
0.87

–
0.98, 1.45
0.71, 1.07

1‡
0.92
0.89
0.63

–
0.79, 1.08
0.73, 1.09
0.38, 0.99

1
1.85

–
1.53, 2.22

1
1.07

–
0.84, 1.34

1
1.05

–
0.90, 1.23

1
1.31

–
1.01, 1.66

1
0.87

–
0.40, 1.64

1
1.12

–
0.73, 1.63

Analyses including adjustment for the basic variables(city, gender, age at exposure, and radiation dose)
plus all 16 risk-factor variables‡
P for trend < 0.05§
Includes unknown or missing data (for <10% of thetotal subjects)†

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cally, the dose response using Cox regression,
including dose as a continuous variable and only
the basic demographic variables (HR, 1.28 at 1 Gy;
95% CI: 1.19, 1.37), was nearly the same as whenall 16 potential confounders also were included(HR, 1.26 at 1 Gy; 95% CI: 1.17, 1.35), indicating
the absence of confounding effects. Nevertheless,because diabetes mellitus was a strong risk factor
for cataract, we included it in further Poisson
regression analyses.
Radiation risk analysis
For the Poisson regression, the best sets of background rates (which included some interactions
among city, sex, and age) and effect-modification
terms were found. For the ERR models, the TSEmodel fit the data slightly better than the attainedage model, so the TSE model was used. However,for the EAR models, the attained-age model provided a better fit than the TSE model, so it wasused. In the following, risk estimates are presented
for an attained age of 70 years after exposure at age
20 years, unless otherwise noted.
ERR models—After optimizing the backgroundmodel, the simplest TSE ERR model with no doseeffect modifiers yielded a linear dose-response
ERR estimate of 0.32 (95% CI: 0.20, 0.47) at 1 Gy.
When a quadratic dose-squared term was added tothe model, its effect was positive, suggesting slight
upward curvature, but the improvement in fit was
not significant (P = 0.34), so it was not pursued
further. Evaluation of potential effect modifiers
showed that city (P = 0.05), sex (P = 0.03), age at
exposure (P = 0.006), and TSE (P < 0.001), but notdiabetes mellitus, modified the radiation effect,with Nagasaki, male sex, younger age at exposure,and shorter TSE having greater radiation ERRs.
With the effect modifiers of city, sex, age at exposure, and TSE, the ERR estimate was calculated asfollows:
0.77 · d · exp(20.88 · c – 0.89 · s – 0.66 · e – 1.59 ·TSE),where d is eye radiation dose, c is city, s is sex, ande is (years of age at exposure – 20)/10, and TSE is(years since exposure – 50)/10.
With use of this model, the sex-averaged ERR
for Hiroshima for a 70-year-old individual exposed
at age 20 years (i.e., 50 years after exposure) was
0.32 (95% CI: 0.09, 0.53; P < 0.001) (Figure 1).
The estimated number of excess cases caused byradiation was 109. Averaged across city, the estimated ERR was 0.49 for males and 0.20 for
females. When averaged across city and sex, theestimated ERR was greater at younger ages at
exposure; estimates for 50 years after exposure
were 0.61, 0.32, and 0.15 for exposure at ages 10,
20, and 30 years, respectively. The negative coeffiRERF Update Volume 23, Issue 2, 2012

Science Articles

Figure 1. Radiation dose response for the relative risk ofcataract surgery for 20 years of age at exposureand attained age of 70 years, and averaged
across gender and city. The excess relative risk
per Gy was 32% (95% CI: 9%, 53%) (P < 0.001).

cient shown for the TSE modifier in the above
equation indicates that the ERR diminished at longer times since radiation exposure.
EAR models—With the best background model,
the simplest EAR model with no dose-effect modifiers yielded a linear dose-response EAR estimateof 19.0 (95% CI: 11.7, 27.2) excess cases per
10,000 person-years at 1 Gy. When a quadraticterm was added to the model, the effect was positive but the improvement in the fit was not significant (P = 0.14). Evaluation of potential effect modifiers showed that city (P = 0.10), sex (P = 0.31),
age at exposure (P = 0.31), and diabetes mellitus(P = 0.44) effects were not significant. Only a positive log attained age effect (P < 0.01) modified theradiation effect. The final EAR model was as follows: 33.2 · d · exp(3.76 · log age), where log age islog attained age.
Thus, the EAR was 33.2 (95% CI: 22.1, 45.2;
P < 0.001) excess cases per 10,000 person-years at
1 Gy, modeled at age 70 years after exposure at age

Figure 2. Dose response: excess absolute risk (EAR) per
10,000 persons per year, modeled for 20 years ofage at exposure and attained age of 70 years,
averaged across gender and city. The excess
cases per 10,000 persons per year per Gy were33 (95% CI: 22, 45) (P < 0.001).
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22
20 years (Figure 2). On the basis of this model, theestimated number of excess cases caused by radiation was 117. The estimated EAR (averaged acrosscity, sex, and age at exposure) increased with attained
age: The EAR was 19 (95% CI: 12, 26) at age 60
years, 33 (95% CI: 22, 45) at age 70 years, and 55(95% CI: 31, 83) at age 80 years, but it was not
significantly affected by age at exposure (P = 0.31).
Threshold level search—With the best models
shown above, we searched for a threshold dose
effect by using a profile likelihood search. The
threshold-dose point estimates were similar for thetwo models: 0.50 Gy (95% CI: 0.10 Gy, 0.95 Gy)for the ERR model and 0.45 Gy (95% CI: 0.10 Gy,
1.05 Gy) for the EAR model.

Discussion
This study provides quantitative evidence forrisk of vision-impairing cataracts at lens doses lessthan 1 Gy. The dose response was nearly linear,
implying there may be risk at fairly low doses. The
best estimate was a 32% excess in the relative risk
at 1 Gy for a 70-year-old individual who received
radiation exposure at age 20 years. The risk was
highest for those who were young at exposure, suggesting that children are especially sensitive to cataract induction by means of radiation. A formal
dose-threshold level analysis provided a best estimate of a threshold level at about one-half of a graybut indicated that the threshold level may be as low
as 0.1 Gy and is unlikely to exceed 1.0 Gy. As such,these data strengthen the foundation for the recent
ICRP guidelines in which the threshold level forabsorbed dose to the lens has been reduced by afactor of 10 to 0.5 Gy.5
A substantial number of screening studies,16–22
including several of medical radiation personnel,23–26 have reported that doses of low-linear
energy transfer radiation less than 1 Gy are associated with posterior subcapsular and cortical opacities, but they were primarily low-grade opacities
that have little effect on visual acuity. Further
details are given in two reviews.27,28 Researchers in
two previous studies29,30 have reported on clinicallyimportant cataracts, but one was based on alphairradiation with uncertain dosimetry,29,30 and theother did not show a significant association but,because of the very low dose distribution, had limited statistical power.9 Thus, the present study provides more convincing evidence than that in previous studies about clinically significant cataracts
caused by radiation in the 0–1 Gy dose range, giventhat it reflects cataract-surgery incidence during a
20-year period in a large cohort of whom more than
1,000 individuals underwent cataract surgery, and
82% of the cohort received doses less than 1 Gy.
Past estimates of threshold doses have been
based on prevalence analyses in A-bomb surviRERF Update Volume 23, Issue 2, 2012

Science Articles
vors4,22,31 and Chernobyl clean-up workers18; allexcept one31 suggested a low-dose threshold level.
This study had a number of strengths. It characterized the radiation risk for cataract surgery incidence in a well-defined cohort with a wide range ofreasonably accurate dose estimates and a high participation rate for up to 60 years after the bombings. Those who performed the medical examinations for confirmation of cataract were blinded to
the radiation dose so as not to bias the assessment.
Furthermore, bias from differential care seeking is
unlikely because there were no economic incentives for some subgroups to get more health carethan others, as health care is free and readily available for all study subjects.
The study also had certain limitations. We did
not account for possible temporal changes in smoking habits, alcohol consumption, or obesity (bodymass index) during the study period. Information
on individual sunlight exposure was not available,
although it is known that the cohort contained few
individuals who had marked occupational sunlight
exposure, and there is no apparent reason why sunlight exposure should be correlated with radiation
dose. There may have been losses to follow-up or
survival biases in the cohort before 1986 (which
was 41 years after the bombings). However, losses
to follow-up (participant attrition) have been independent of radiation dose in the AHS, and the mod-23
est dose-related differences in survival as a result of
the radiation-cancer association are unlikely to berelated also to cataract outcomes. Cataract surgery
is an imperfect surrogate for a vision-impairing
cataract because surgery may depend on health status, age, visual acuity in the other eye, and otherfactors that limit the sensitivity in ascertaining
vision-limiting cataracts,32 but there is no reason tothink that the sensitivity varied by radiation dose.
Because the study was based on a brief, single
radiation exposure, the generalization of the risk
estimates to groups exposed to protracted or highly
fractionated radiation is uncertain.
In conclusion, a 32% (95% CI: 9%, 53%) excess
was found at 1 Gy in the relative risk for incident
cataract surgery, an excess amounting to 33 extra
cases per 10,000 persons per year per gray. The
near-linear dose response suggests there may beradiation risk for clinically important cataracts at
relatively low doses, and the data are compatible
with a dose-response threshold level between about
0.1 and 1 Gy but not with threshold values above 1
Gy. Finding a near-linear dose response and an
estimated-dose threshold level of approximately
0.5 Gy for clinically important cataracts among
A-bomb survivors significantly strengthens the scientific foundation for the recent ICRP statement5
that considers the threshold dose for the lens of theeye to be 0.5 Gy rather than a much higher value.

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23. Kleiman NJ, Cabrera M, Duran G, Ramirez R, Duran A, Vano E. Occupational risk of radiation cataract ininterventional cardiology. Invest Ophthalmol Vis Sci 2009; 49(suppl):511.
24. Vano E, Kleiman NJ, Duran A, Rehani MM, Echeverri D, Cabrera M. Radiation cataract risk in interventional
cardiology personnel. Radiat Res 2010; 174(4):490-5.
25. Ciraj-Bjelac O, Rehani MM, Sim KH, Liew HB, Vano E, Kleiman NJ. Risk for radiation-induced cataract for
staff in interventional cardiology: Is there reason for concern? Catheter Cardiovasc Interv 2010; 76(6):826-34.
26. Mrena S, Kivela T, Kurttio P, Auvinen A. Lens opacities among physicians occupationally exposed to ionizing
radiation—a pilot study in Finland. Scand J Work Environ Health 2011; 37(3):237-43.
27. Ainsbury EA, Bouffler SD, Doerr W, Graw J, Muirhead CR, Edwards AA, Cooper J. Radiation
cataractogenesis: A review of recent studies. Radiat Res 2009; 172:1-9.
28. Shore RE, Neriishi K, Nakashima E. Epidemiologic studies of cataract risk at low-to-moderate radiation
doses: (not) seeing is believing. Radiat Res 2010; 174:889-94.
29. Chmelevsky D, Mays CW, Spiess H, Stefani FH, Kellerer AM. An epidemiological assessment of lens
opacification that impaired vision in patients injected with radium-224. Radiat Res 1988; 115(2):238-57.
30. Taylor DM, Thorne MC. The potential for irradiation of the lens and cataract induction by incorporated alphaemitting radionuclides. Health Phys 1988; 54(2):171-9.
31. Otake M, Schull WJ. Radiation-related posterior lenticular opacities in Hiroshima and Nagasaki atomic bomb
survivors based on the DS86 dosimetry system. Radiat Res 1990; 121(1):3-13.
32. Nakashima E, Fujii Y, Neriishi K, Minamoto A. Assessment of misclassification in a binary response:
Recovering information on clinically significant cataract prevalence from cataract surgery data in atomicbomb survivors. J Jpn Stat Soc 2011; 41(1):1-15.
Return to Table of Contents

RERF Update Volume 23, Issue 2, 2012

25

Science Articles

Long-term Trends of Thyroid Cancer Risk among
Japanese Atomic-bomb Survivors:
60 Years after Exposure*
Kyoji Furukawa
Department of Statistics, RERF
*This article is based on the following publication:
Furukawa K, Preston DL, Funamoto S, Yonehara S, Ito M, Tokuoka S, Sugiyama H, Soda M,
Ozasa K, Mabuchi K. Long-term trend of thyroid cancer risk among Japanese atomic-bomb
survivors: 60 years after exposure. Int J Cancer 2012 (August 16) [Epub ahead of print](doi:10.1002/ijc.27749)

Findings of This Study
Among the A-bomb survivors exposed to radiation before reaching adulthood (before age 20),
risk of thyroid cancer incidence tended to increase

with radiation dose. Although excess risk (relative increase in incidence based on comparison
with the non-exposed) from childhood exposure
decreases with attained age, the risk persists more

Table. Observed and fitted cases of thyroid cancer incidence in the LSS (1958–2005) by categories of dose andother variables
Age at exposure < 20 years

Age at exposure >= 20 years

Fitted valuesn45,738

Case Ratea

BackFitted AFb
ground excess (%)

191

153.5

12.2

41.1

Fitted valuesn

95% CI

Case Ratea

BackFitted AFb
ground excess (%)

95% CI

36*

Total(22, 46)

59,663

180

12.5

173.2

3.3

4*

(1, 17)14
23

Sex( 0, 27)(13, 32)

Male
Female21,571
24,167

40
151

5.6
17.5

33.7
119.7

5.6
35.5

21,31938,344

21
159

5.0
15.5

21.6
151.6

0.2
3.1

1
2

(0, 6)(0, 9)

NIC
0–0.005
0.005–0.1
0.1–0.25
0.25–0.5
0.5–1
1+

10,867
15,243
12,143
2,981
1,798
1,405
1,301

33
45
37
20
15
15
26

8.6
8.8
8.8
19.1
24.0
31.8
63.5

26.6
53.9
39.6
10.9
7.5
7.6
7.3

Weighted thyroid dose (Gy)0.0
0 ( 0, 0)14,3770.1
0 ( 0, 0)
19,071
2.7
6 ( 3, 9)15,485
3.8
26 (14, 35)
4,308
5.3
41 (25, 53)
2,695
9.0
54 (38, 66)
2,111
20.1
73 (59, 83)
1,616

25
61
50
17
11
8
8

6.9
13.4
13.5
16.4
17.1
16.0
21.8

31.4
57.7
46.3
14.2
9.2
8.0
6.4

0.0
0.0
0.2
0.3
0.4
0.7
1.7

0
0
0
2
4
9
21

(0, 0)(0, 0)(0, 2)(0, 11)(1, 22)(2, 35)(6, 59)

38
34
53
45
21

5.9
10.2
16.8
21.0
30.3

24.9
26.3
41.3
42.2
18.8

13.4
8.6
10.4
6.9
1.8

Attained age (year)
35 (13, 52)
25 (14, 33)
20 (10, 28)
14 ( 6, 22)
9 ( 3, 17)

3
15
29
44
89

7.8
9.2
9.5
11.2
16.4

2.6
13.2
29.6
45.0
82.7

0.3
0.6
0.7
0.7
0.9

9
5
2
2
1

(2, 31)(1, 18)(0, 12)(0, 8)(0, 6)

22
17
31
57
64

7.1
4.8
9.3
18.4
23.6

11.2
17.0
26.0
40.0
59.3

5.7
6.6
7.9
9.6
11.1

Calendar year
34 ( 8, 58)
28 (12, 42)
23 (13, 32)
19 (10, 27)
16 ( 6, 24)

45
40
30
44
21

10.8
9.5
9.9
22.6
20.3

41.9
40.7
36.1
31.1
23.4

0.7
0.7
0.7
0.7
0.5

2
2
2
2
2

(0, 10)(0, 9)(0, 8)(0, 8)(0, 8)

–39
40–49
50–59
60–69
70–
1958–1965
1966–1975
1976–1985
1986–1995
1996–2005

45,738c
45,04243,89041,971
38,181

59,663c50,42138,37926,396
15,416

a: Cases per 100,000 person-years (PY)
b: Attributable faction (*among people with dose greater than 0.005 Gy weighted thyroid dose)c: The number of subjects at risk at the beginning of the period
NIC: Subjects who were not in the cities at the time of bombings
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RERF Update Volume 23, Issue 2, 2012

Science Articles

26

than 50 years after the atomic bombings. On theother hand, no clear effect on thyroid cancer wasobserved from radiation exposure occurring in
adulthood (at or after age 20).

Explanation
Thyroid cancer, while not a frequent cancer, hasa relatively strong association with radiation, and it
was a type of solid cancer for which association
with radiation was identified early on (10-plus
years after the atomic bombings) in research
involving the A-bomb survivors. Multiple epidemiological and other studies have reported that the
thyroid is highly susceptible to the effects of radiation exposure before adulthood in particular, but
not much has been elucidated in terms of whether
there are any long-term exposure effects or effects
from exposure after reaching adulthood. In thisstudy of approximately 100,000 members of the
120,000-subject Life Span Study (LSS) cohort, theauthors analyzed association between thyroid cancer incidence and exposure dose up to 60 years
after the atomic bombings using the latest cancer
incidence data including detailed pathologicaldiagnoses.
1. Purpose of study: To examine long-term temporal trends and age-at-exposure variations in radiation-induced risk of thyroid cancer.

Figure 1. Fitted dose response functions for thyroid cancer
incidence in the LSS cohort. The solid line is thefitted linear excess relative risk (ERR) dose response, and the dashed curve is the fitted ERR
based on linear-exponential dose responsemodel. The points are non-parametric estimatesof the ERR in dose categories with 95% CIs. Theline and points are all gender-averaged estimatesat age 60 after exposure at age 10.

2. Based on the cancer incidence data including
detailed pathological diagnoses: 371 thyroid cancer cases (first primary) were clinically and microscopically confirmed among 105,401 cohort members for the period from 1958 through 2005
(Table). Poisson regression models were used foranalyzing association between thyroid cancer incidence and radiation dose, age, sex, and other factors.
3. Results of the study: For exposure to 1 Gy ofradiation at age 10, it was estimated that thyroid
cancer incidence at age 60 would increase by
128% (95% confidence interval [CI]: 60–270%)
compared with that of the non-exposed, or an
increase of 2.28 times (Figure 1). Radiation-associated excess risk based on the same attained age
decreased sharply with increasing age at exposure,and there was no clear evidence of increased thyroid cancer rates for those exposed at or after age
20 (Figure 2). About 36% of the 113 thyroid cancer
cases among the LSS cohort exposed to radiationof at least 5 mGy before age 20 were estimatedto be attributable to radiation exposure (Table).
While excess risk of thyroid cancer associated withchildhood exposure has decreased with increasing
attained age, excess risk persists even after morethan 50 years since exposure.
Return to Table of Contents

Figure 2. Fitted temporal patterns and age-at-exposure
variation in the radiation-associated risk for thyroid
cancer in the LSS cohort. The upper panel presents ERR at 1 Gy and the lower panel the fitted
excess absolute rate at 100,000 person-years-Gy,
with attained age for ages at exposure of 5 (“0–9”for categorical estimates), 15 (“10–19”), 25(“20–29”) and 41 (“30–”) years. All curves andpoints are gender-averaged estimates.

RERF Update Volume 23, Issue 2, 2012

Human Interest Notes

27

Farewell Service and Memorial Gathering Held for theLate Dr. Itsuzo Shigematsu
Kazunori Kodama, Chief Scientist
Yutaka Ogasawara, Assistant Chief of Secretariat
Ayako Ishibe, Directors’ Office
Dr. Itsuzo Shigematsu, who had served as RERF
Emeritus Consultant after a distinguished term of
16 years as RERF Chairman, passed away on February 6, 2012. The following is our report on his
farewell service and memorial gathering held inTokyo and Hiroshima, respectively.

Farewell Service for Dr. Itsuzo Shigematsu
The farewell service for the late Dr. Itsuzo
Shigematsu was held at the Gakushi Kaikan inTokyo on April 22, 2012. The service was organized by RERF Chairman Toshiteru Okubo, former RERF Vice Chairman Senjun Taira, and fiveother persons, and its representative working committee members included one of us (KK) and Dr.
Hiroshi Yanagawa (professor emeritus of Jichi
Medical University, former Saitama Prefectural
University President), who was a favorite pupil of
Dr. Shigematsu’s.
Family members of the deceased were in attendance, including Dr. Shigematsu’s wife Mrs.
Yoshie Shigematsu, eldest son Mr. Ken Shigematsu
and his wife, daughter Mrs. Eiko Sato, and three
grandchildren. The service was a truly stately occasion, with attendance of a total of 232 guests thatpacked the venue including Dr. Senya Toyama,
Director-General of Health Service Bureau, Ministry of Health, Labour and Welfare (MHLW), Dr.
Shigenobu Nagataki, former RERF Chairman,
those working in the fields of epidemiology andpublic health, and many students of the deceased.
With Dr. Yanagawa presiding over the service,
there was a silent prayer offered to the soul of thedeceased, followed by representative organizer’s
greetings by Dr. Okubo, and words by which toremember the deceased delivered by Dr. Tadao
Shimao (Chairman of the Scientific and Ethics
Committee for the Clinical Study of the F1 Offspring of A-bomb Survivors), Dr. Nagataki, and six
more guests.
At the service venue, an exhibit of posters featured many memorable photographs of Dr.
Shigematsu during childhood, as a student, in the
military, when he was with the Japanese Institute of
Public Health, at Kanazawa University, and at
RERF, all of which were prepared through thedetermined efforts of volunteers from RERF, Jichi
Return to Table of Contents

Medical University, and Saitama Prefectural University. Moreover, the venue exhibited numerous
items related to Dr. Shigematsu including awards/
medals and commendations, and a model of thelight cruiser Kuma, on which Dr. Shigematsu
served when he was in the Japanese Navy. While
viewing the memorial items, the attendees reminisced about their shared past with Dr. Shigematsu.
Many messages arrived from overseas sent by
those mourning Dr. Shigematsu’s passing, including Director Patricia R. Worthington, Office of
Health and Safety, Office of Health, Safety andSecurity, Department of Energy, former RERF
Chairman Burton G. Bennett, former RERF Vice
Chairman J.W. Thiessen, WHO Emeritus DirectorGeneral Hiroshi Nakajima, Professor Emeritus K.
Sankaranarayanan of Leiden University, who was
Dr. Shigematsu’s epidemiologist friend from long
ago, and Dr. Warren K. Sinclair, U.S. Chairman of
the Senior Review Group for DS02.
Finally, the eldest son Mr. Ken Shigematsu
spoke on behalf of the bereaved family, and thetwo-hour service came to an end with Dr. Taira’s
closing address. We later received positive feedback from the attendees that it had been a memorable and meaningful occasion.
A collection of essays contributed by more than
100 persons titled “To Dr. Itsuzo Shigematsu with
Gratitude” was presented to the attendees as aremembrance.

At the farewell service for Dr. Itsuzo Shigematsu (Tokyo)

RERF Update Volume 23, Issue 2, 2012

28

Human Interest Notes

Memorial Gathering for Dr. Itsuzo Shigematsu
The memorial gathering for Dr. Itsuzo
Shigematsu was held at Hiroshima City Bunka
Koryu Kaikan (former Kosei-Nenkin Kaikan) on
June 30, 2012. The event was organized by RERF
Chairman Toshiteru Okubo, Dr. Nanao Kamada,Dr. Kozo Sanada, and Dr. Hiroo Dohy—the present
and former presidents of the Hiroshima International Council for Health Care of the Radiationexposed (HICARE)—and Mr. Toraji Miyagawa,President, ABCC-RERF Hiroshima OB-Kai (Retirees Club). I (KK) served as the representative
working committee member.
There were a total of 103 participants at
the gathering: seven bereaved family members
from Tokyo including Dr. Shigematsu’s wife
Yoshie, and relevant individuals in the local areafrom Hiroshima Prefecture and City governments,
Hiroshima University, Hiroshima Prefectural andCity Medical Associations, the local news media,
A-bomb survivors, former and present employees
at ABCC-RERF, and individuals from Nagasaki.
Ms. Reiko Horimukai served as emcee of thegathering. Following a moment of silence, Dr.
Okubo delivered representative organizer’s greetings, and then former RERF Vice Chairman
William J. Schull, who came to Hiroshima all theway from Houston, spoke of his memories of Dr.
Shigematsu.
The gathering in Hiroshima had several uniquecharacteristics: to note among them was a piano
recital by Dr. Shigematsu’s granddaughter, Hanako
Shigematsu, who is an established pianist. Hanako
performed two poignant pieces, interspersedwith remembrances of her late grandfather. The
gathering also included a slideshow titled “Dr.
Shigematsu, Hiroshima, and us,” during which
we talked about Dr. Shigematsu’s 16 years in
Hiroshima based on a presentation mainly of slides
I (KK) had prepared. In addition, we showed avideo recording of some of Dr. Shigematsu’s lectures and interviews. We believe that all attendees
were able to share with each other their many
valuable memories of Dr. Shigematsu. Posters anditems exhibited at the farewell service in Tokyo
were also used at this memorial gathering in
Hiroshima.
Finally, Mr. Ken Shigematsu then spoke onbehalf of the bereaved family, and the memorial
gathering came to an end with Dr. Kamada’s closing address.
The planning and implementation of the gathering were handled by RERF volunteers, all of whom
provided dedicated service. We would like to takethis opportunity to thank all RERF employees,
including those not directly involved in the relevant
work, for their help in putting on the event.
We would like to close this report by once again
expressing our deepest condolences on the passingof Dr. Shigematsu.

At the memorial gathering for Dr. Itsuzo Shigematsu (Hiroshima). Mr. Ken Shigematsu (far left)offering words of gratitude on the bereaved family’s behalf.

Return to Table of Contents

RERF Update Volume 23, Issue 2, 201229

Human Interest Notes

In memory of Dr. Shoji Tokuoka
Kazunori Kodama, Chief Scientist
Dr. Shoji Tokuoka, who had dedicated himself
for so long to the development of pathologicalresearch at RERF, passed away on September 29,
2012. He was 85 years of age. I would like toexpress my heartfelt appreciation for all of his contributions over so many years and extend my deepest condolences to his family.
Dr. Tokuoka was born in 1927, graduated from
Hiroshima Medical College in 1952, and started
his career in the field of pathology. He worked asa resident at the Institute of Pathology, Universityof Tennessee School of Medicine, Memphis, Tennessee, and at the Department of Pathology, theUniversity of Texas M.D. Anderson Hospital andTumor Institute, Houston, Texas, for a total of three
years. He then served as an associate professor inpathology at Hiroshima University Faculty of Medicine, and as a professor in pathology, Kagoshima
University Faculty of Medicine, before assuming
the post of pathology professor, Hiroshima University Faculty of Medicine. Starting in 1986, heserved as dean of the Hiroshima University Facultyof Medicine for two years.
Dr. Tokuoka’s involvement in research on lateeffects of A-bomb radiation began in 1959, when
he was appointed to serve as a contract pathologist at the Atomic Bomb Casualty Commission(ABCC). After ABCC’s reorganization into RERF,
he served as an expert advisor and a consultant to
the Department of Pathology (later Departmentof Epidemiologic Pathology) starting in 1976 and1982, respectively, providing research guidance
to RERF researchers. Starting in 1986, he concurrently served as a consultant to the Department ofRadiobiology. After his retirement from Hiroshima
University, he assumed the newly created post ofsenior consulting scientist at RERF and engaged
in research himself as an RERF consultant fromReturn to Table of Contents

1994 until his
death in 2012. Heremained active asa researcher untilthat time.
At RERF, Dr.
Tokuoka focusedon site-specificcancer research
into association
between A-bombradiation and canDr. Shoji Tokuoka in 2009
cer risks basedon extraordinarily
accurate diagnoses made by utilizing local cancer
registries and tissue registries, the latter of which
are based on pathologist reports and both of whichwere implemented in Hiroshima and Nagasaki earlier than most of other registries in Japan. This
research has been the centerpiece of the collaborative studies between RERF and the U.S. National
Cancer Institute’s Center for Cancer Research,leading to numerous papers on cancers of the liver,
salivary gland, skin, thyroid, ovary, breast, lung,brain tumor, and lymphoma. This research has
been taken over by researchers mentored by Dr.
Tokuoka and successfully continues to date.
Dr. Tokuoka devoted his life to pathologicalresearch as just described, and I understand that his
grandson has decided to tread in his grandfather’sfootsteps by launching his career in the same fieldof pathology. I am sure that Dr. Tokuoka would feelreassured and pleased.
In conclusion, I would like again to express myheartfelt appreciation for Dr. Tokuoka’s contributions to the progress of RERF’s research over somany years. May his soul rest in peace.

RERF Update Volume 23, Issue 2, 2012

30

Facts and Figures

Public Relations Activities at RERF
Takanobu Teramoto, Executive Director
RERF conducts its public relations activities
with the aim of enhancing the transparency andpromoting the positive contributions to society of
the foundation’s scientific research. With the drastic increase in inquiries for radiation-risk information in the wake of the Fukushima nuclear crisis in
March 2011, we are placing ever more emphasis oncommunicating accurate information on radiation
risk.
Among the different means for public relations,the internet is crucial for the foundation’s worldwide information dissemination as it aims to contribute to improving human health the world over.
The RERF website is presented in both English andJapanese to provide information on radiation risk
and RERF’s recent papers and events. Moreover,data on the Life Span Study (LSS) and RERF’s
other major research projects are available on thewebsite for outside researchers to download for use
in their own research.
Immediately following the Fukushima nuclear
crisis, RERF developed a special website in English and Japanese to start providing information
most relevant to radiation risk and exposure. At thepeak on March 15, 2011, the number of daily
access registered to RERF’s website was approximately 2 million hits (increase of about 50 times
the number before the crisis) and 30,000 visitors(an increase of more than 20 times), respectively. A
considerable number of questions regarding radiation risk reach RERF via its website, and with help
from the research staff, RERF has responded toeach inquiry.

An important part of our public relations activities is introducing the foundation’s research tothe public, including the A-bomb survivors in
Hiroshima and Nagasaki, to gain their support andunderstanding of our work. RERF’s Open House
events are held at both the Hiroshima and Nagasaki
Laboratories every August and represent the foundation’s largest public outreach effort planned andcarried out by the foundation’s employees. The
events are held over two days in each of the cities on the A-bombing anniversaries (August 6 forHiroshima and August 9 for Nagasaki) and the day
preceding each date. At such times, RERF welcomes many visitors from throughout Japan andfrom abroad. The Open House features exhibits
introducing RERF’s research programs, lectures,and scientific experiments, with the foundation’s
officials, research scientists, and general employees
alike available for offering explanations to the visitors. Attracting about 1,300 visitors in Hiroshima
and Nagasaki combined, this year’s Open House
events included a special exhibit on low-dose exposure in hopes of widely conveying to as many people as possible accurate information regarding radiation risk. Aspiring to remain a friendly researchorganization, RERF officials and employees makean effort to warmly greet the Open House visitors,
from whom we have received positive feedback.
Visitors are welcome to tour RERF’s facilities atother occasions besides the Open House events,
and during the school excursion seasons of spring
and fall in particular, we welcome many young
student visitors.

Executive Director Takanobu Teramoto briefing Open Housevisitors in Hiroshima

Students on a school excursion touring the RERF facilities
in Hiroshima

Return to Table of Contents

RERF Update Volume 23, Issue 2, 2012

Facts and Figures
RERF started holding its public lecture series in2010. We hold such lectures in conference halls at
the Peace Memorial Parks in Hiroshima and Nagasaki. The second public lectures, held in 2011–2012, aimed at communicating with the public
about accurate information about radiation risk andfeatured two talks titled “Thinking about low-doseradiation exposure” and “Methods for radiationdose assessment.”
Since the number of interviews and stories
requested by the mass media drastically increased
following the Fukushima nuclear crisis, in 2011 weReturn to Table of Contents

31
initiated a seminar specifically designed for thejournalists and reporters. Our focus for the media
seminar is again to communicate accurate information on radiation risk. In addition, we have heldpress conferences and sent out press releases whenmajor events are held and papers are released.
RERF will continue making efforts to conduct
its public relations activities systematically anddeliberately for the purpose of improving transparency of its research and publicizing its researchachievements.

RERF Update Volume 23, Issue 2, 2012

Recent Publications

Recent Publications(Japanese): the original article is in Japanese.

Cologne JB: Commentary on “Development ofa prediction model for 10-year risk of hepatocellular carcinoma: The Japan Public HealthCenter-based Prospective Study Cohort II” by
Michikawa et al. Prevent Med 2012 (August);
55(2):144-5.
Cologne JB, Hsu WL, Abbott RD, Ohishi W, Grant
EJ, Fujiwara S, Cullings HM: Proportional hazards regression in epidemiologic follow-up studies: An intuitive consideration of primary timescale. Epidemiology 2012 (July); 23(4):565-73.
(RERF Report 12-11)
Cologne JB, Preston DL, Imai K, Misumi M,
Yoshida K, Hayashi T, Nakachi K: Conventional
case-cohort design and analysis for studies ofinteraction. Int J Epidemiol 2012 (August);
41(4):1174-86. (RERF Report 19-11)
Douple EB, Boice JD: In memoriam–Seymour
Jablon (June 2, 1918–April 9, 2012). Radiat Res
2012 (September); 178(3):246-7.
Egawa H, Furukawa K, Preston D, Funamoto S,
Yonehara S, Matsuo T, Tokuoka S, Suyama A,
Ozasa K, Kodama K, Mabuchi K: Radiation andsmoking effects on lung cancer incidence byhistological types among atomic bomb survivors.
Radiat Res 2012 (September); 178(3):191-201.
(RERF Report 11-11)
Fujiki H, Imai K, Nakachi K, Shimizu M, Moriwaki
H, Suganuma M: Challenging the effectivenessof green tea in primary and tertiary cancer prevention. J Cancer Res Clin Oncol 2012 (August);
138(8):1259-70.
Furukawa K, Preston D, Funamoto S, Yonehara S,
Ito M, Tokuoka S, Sugiyama H, Soda M, Ozasa
K, Mabuchi K: Long-term trend of thyroid cancer risk among Japanese atomic-bomb survivors:
60 years after exposure. Int J Cancer 2012 (July31). doi: 10.1002/ijc.27749. [Epub ahead ofprint]. (RERF Report 5-12)
Grant EJ, Ozasa K, Preston DL, Suyama A,
Shimizu Y, Sakata R, Sugiyama H, Pham TM,
Cologne JB, Yamada M, De Roos AJ, Kopecky
KJ, Porter MP, Seixas N, Davis S: Effects ofradiation and lifestyle factors on risks of urothelial carcinoma in the Life Span Study ofatomic bomb survivors. Radiat Res 2012 (July);
177(1):86-98. (RERF Report 16-11)
Return to Table of Contents

32
Imai K, Hayashi T, Yamaoka M, Kajimura J,
Yoshida K, Kusunoki Y, Nakachi K: Effects of
NKG2D haplotypes on the cell-surface expression of NKG2D protein on natural killer andCD8 T cells of peripheral blood among atomicbomb survivors. Hum Immunol 2012 (June);73(6):686-91. (RERF Report 21-11)
Katayama H: RERF databases and implications
for future studies. Radiat Prot Dosimetry 2012
(October); 151(4):677-81.
Kodama K, Ozasa K, Katayama H, Shore RE,
Okubo T: Radiation effects on cancer risks in theLife Span Study cohort. Radiat Prot Dosimetry
2012 (October); 151:674-6.
Kodama Y, Noda A, Booth C, Breault D, Suda T,
Hendry J, Shinohara T, Rübe C, Nishimura EK,
Mitani H, Nakamura N, Niwa O: International
workshop: Radiation effects on mutation insomatic and germline stem cells. Int J Radiat
Biol 2012 (June); 88(6):501-6.
Neriishi K, Nakashima E, Akahoshi M, Hida A,
Grant EJ, Masunari N, Funamoto S, Minamoto
A, Fujiwara S, Shore RE: Radiation dose andcataract surgery incidence in atomic bomb survivors, 1986–2005. Radiology 2012 (October);
265(1):167-74. (RERF Report 14-11)
Noda A, Nakamura N: Revisiting mutation rate
calculations. Hoshasen Seibutsu Kenkyu [Radiat
Biol Res Commun] 2012 (March); 47(1):1-7.
(Japanese)
Nonaka Y, Shimizu Y, Ozasa K, Misumi M,
Cullings HM, Kasagi F: Application of a change
point model to atomic-bomb survivor data:
Radiation risk of noncancer disease mortality.
Keiryo Seibutsugaku [Jpn J Biom] 2012 (May);32(2):75-96. (RERF Report 3-11)
Okubo T: Obituary: Itsuzo Shigematsu. J Radiol
Prot 2012 (September); 32(3):359.
Okubo T: Long-term epidemiological studies
of atomic bomb survivors in Hiroshima andNagasaki: Study populations, dosimetry andsummary of health effects. Radiat Prot Dosimetry 2012 (October); 151(4):671-3.
Okubo T (ed): MHLW Grants. FY2010 Report ofAtomic Bomb Disease Research Project. 2011
(September), 63 p. (Japanese)
Okubo T (ed): MHLW Grants. FY2011 Report ofAtomic Bomb Disease Research Project. 2012
RERF Update Volume 23, Issue 2, 2012

Recent Publications(September), 92 p. (Japanese)
Otonari J, Nagano J, Morita M, Budhathoki S,
Tashiro N, Toyomura K, Kono S, Imai K, Ohnaka
K, Takayanagi R: Neuroticism and extraversion
personality traits, health behaviours, and subjective well-being: the Fukuoka Study (Japan). Qual
Life Res 2012 (December); 21(10):1847-55. doi:
10.1007/s11136-011-0098-y.

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Follow up study among atomic bomb survivors.
Ronenki Ninchisho Kenkyukai Shi [Proceedingsof the Annual Meeting of the Japanese ResearchGroup on Senile Dementia] 2012 (August);
19(3):73-5. (Japanese)

Ozasa K: Effects of atomic-bomb radiation on children. Child Health 2012 (September); 15:14-7.
(Japanese)
Sakata R, Grant EJ, Ozasa K: Long-term followup of atomic bomb survivors. Maturitus 2012
(June); 72(2):99-103. (RERF Report 2-12)
Sakata R, Kleinerman RA, Mabuchi K, Stovall
M, Smith SA, Wactawski-Wende J, Cookfair
DL, Boice JD, Jr., Inskip PD: Cancer mortality following radiotherapy for benign gynecologic disorders. Radiat Res 2012 (September);
178:266-79.
Shi L, Fujioka K, Sun J, Kinomura A, Inaba T,
Ikura T, Ohtaki M, Yoshida M, Kodama Y,
Livingston GK, Kamiya K, Tashiro S: A modified system for analyzing ionizing radiationinduced chromosome abnormalities. Radiat Res
2012 (May); 177:533-8.
Sonoyama T, Sakai A, Mita Y, Yasuda Y, Kawamoto
H, Yagi T, Yoshioka M, Mimura T, Nakachi K,
Ouchida M, Yamamoto K, Shimizu K: TP53
codon 72 polymorphism is associated with pancreatic cancer risk in males, smokers and drinkers. Mol Med Report 2011 (May); 4(3):489-95.
Usui S, Matsumura M, Yanagida J, Suyama A,
Tatsukawa Y, Inoue N, Kidani Y, Egawa M,
Kubota M, Nakahara H, Tsumura H, Okada
T, Ishida K, Tojo T, Mukai M, Nakamoto K,
Kotajima Y, Shinoda H, Fukuhara M, Kouno N,
Yamaguchi N, Mori H: Report on the results ofthe eighteenth medical examination of atomic
bomb survivors resident in North America.
Hiroshima Igaku [J Hiroshima Med Assoc] 2012
(May); 65:357-82.
Watanabe T, Kuramochi H, Takahashi A, Imai K,
Katsuta N, Nakayama T, Fujiki H, Suganuma M:
Higher cell stiffness indicating lower metastatic
potential in B16 melanoma cell variants and in(-)-epigallocatechin gallate-treated cells. J Cancer Res Clin Oncol 2012 (May); 138(5):859-66.
Yamada M: Epidemiological study on dementia–
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RERF Update Volume 23, Issue 2, 2012