bluuebunny/crossref_metadata_2025 huggingface dataset:
MO‐B‐213‐02: History and Future Outlook for the AAPM Professional Liability Insurance Program
Authors: Fuller G.
Published: June 2015

The AAPM Professional Liability Insurance program provides a unique ability for medical physicists to obtain liability coverage for risks arising from the practice of medical physics. In 2015, the program introduces a new occurrence‐form coverage option which has important cost and functional differences from the existing claims‐made coverage. Since both forms will be offered to new and renewing policy holders, the details and implications of these two options will be explained. A brief history of the program will be given to review the collaboration between AAPM and its insurance company partners that established and maintains the program that is available today. The future outlook of the program will include an overview of threats and opportunities that affect AAPM members’ ability to obtain cost‐effective coverage in the future.

Learning Objectives:

Gain understanding of the professional liability insurance program offered to AAPM members

Gain understanding of the difference between claims‐made form and occurrence form of coverage

Gain understanding of the role of AAPM in operating the professional liability insurance program

Graham Fuller is an employee of Mercer Consumer which is the broker and administrator of the AAPM Professional Liability Insurance program.
MO‐B‐304‐01: JACMP: An Innovation in Medical Physics Publishing
Authors: Mills M.
Published: June 2015

The JACMP began publication in February, 2000 and is the world's oldest open‐access medical specialty journal. Today it publishes about 200 articles in six issues annually. The JACMP archive experiences about 400,000.pdf downloads annually and a typical JACMP.pdf article is downloaded about 600 or 700 times during the first year after publication. Anyone with web access can reach these articles, having wide distribution and benefiting as many patients as possible.

Preparing a manuscript for publication in the JACMP (or any other journal) is a straightforward process. The primary purpose of a manuscript is to communicate knowledge and experience. A relatively fixed format has been developed to meet this goal; this format consists of an Abstract, Introduction, Methods and Materials, Results, and Conclusions. In addition to fitting your experience into that format, it is important to recognize your audience and direct your manuscript to that audience. Finally, it is important to write your manuscript in clear English, enlisting the aid of a copyeditor, if such an individual is available.

Reviewing the articles submitted to JACMP is a rewarding yet difficult task. A reviewer must evaluate submitted articles critically, objectively, and express opinions diplomatically regarding work presented to the journal. A perspective from a JACMP section editor and experienced reviewer will describe the key points that progress a journal article to publication. As a reviewer, the difficulties experienced as a reviewer such as an incomplete or incorrect citations, incorrect formats, etc. will also be described.

Learning Objectives:

Attendees will learn the history and philosophy behind the development of the Journal of Applied Clinical Medical Physics.

After attending this presentation, the participant will be able to prepare a well‐written manuscript suitable for publication in the JACMP or any other peer‐reviewed journal.

Attendees will learn what typical submission mistakes and difficulties are from the perspective of a section editor and experienced article reviewer.
MO‐B‐304‐03: Inside the Mind of a JACMP Reviewer
Authors: Richardson S.
Published: June 2015

The JACMP began publication in February, 2000 and is the world's oldest open‐access medical specialty journal. Today it publishes about 200 articles in six issues annually. The JACMP archive experiences about 400,000.pdf downloads annually and a typical JACMP.pdf article is downloaded about 600 or 700 times during the first year after publication. Anyone with web access can reach these articles, having wide distribution and benefiting as many patients as possible.

Preparing a manuscript for publication in the JACMP (or any other journal) is a straightforward process. The primary purpose of a manuscript is to communicate knowledge and experience. A relatively fixed format has been developed to meet this goal; this format consists of an Abstract, Introduction, Methods and Materials, Results, and Conclusions. In addition to fitting your experience into that format, it is important to recognize your audience and direct your manuscript to that audience. Finally, it is important to write your manuscript in clear English, enlisting the aid of a copyeditor, if such an individual is available.

Reviewing the articles submitted to JACMP is a rewarding yet difficult task. A reviewer must evaluate submitted articles critically, objectively, and express opinions diplomatically regarding work presented to the journal. A perspective from a JACMP section editor and experienced reviewer will describe the key points that progress a journal article to publication. As a reviewer, the difficulties experienced as a reviewer such as an incomplete or incorrect citations, incorrect formats, etc. will also be described.

Learning Objectives:

Attendees will learn the history and philosophy behind the development of the Journal of Applied Clinical Medical Physics.

After attending this presentation, the participant will be able to prepare a well‐written manuscript suitable for publication in the JACMP or any other peer‐reviewed journal.

Attendees will learn what typical submission mistakes and difficulties are from the perspective of a section editor and experienced article reviewer.
MO‐B‐BRB‐00: Optimizing the Treatment Planning Process
Authors: Feng Wenzheng
Published: June 2015

The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image‐guided‐radiation‐therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality.

In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include:

Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS.

Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process

Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning

Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment.

Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi‐automatic plan evaluation, (e) quality checklist for error prevention, (f) iterative process, (g) balance of speed and quality

Learning Objectives:

Gain familiarity with the workflow of modern treatment planning process.

Understand the scope and challenges of managing modern treatment planning processes.

Gain familiarity with Lean Six Sigma approaches and their implementation in the treatment planning workflow.
MO‐D‐213‐02: Quality Improvement Through a Failure Mode and Effects Analysis of Pediatric External Beam Radiotherapy
Authors: Gray J , Lukose R , Bronson J , Chandler B , Merchant T , Farr J
Published: June 2015

Purpose:

To conduct a failure mode and effects analysis (FMEA) as per AAPM Task Group 100 on clinical processes associated with teletherapy, and the development of mitigations for processes with identified high risk.

Methods:

A FMEA was conducted on clinical processes relating to teletherapy treatment plan development and delivery. Nine major processes were identified for analysis. These steps included CT simulation, data transfer, image registration and segmentation, treatment planning, plan approval and preparation, and initial and subsequent treatments. Process tree mapping was utilized to identify the steps contained within each process. Failure modes (FM) were identified and evaluated with a scale of 1–10 based upon three metrics: the severity of the effect, the probability of occurrence, and the detectability of the cause. The analyzed metrics were scored as follows: severity – no harm = 1, lethal = 10; probability – not likely = 1, certainty = 10; detectability – always detected = 1, undetectable = 10. The three metrics were combined multiplicatively to determine the risk priority number (RPN) which defined the overall score for each FM and the order in which process modifications should be deployed.

Results:

Eighty‐nine procedural steps were identified with 186 FM accompanied by 193 failure effects with 213 potential causes. Eighty‐one of the FM were scored with a RPN > 10, and mitigations were developed for FM with RPN values exceeding ten. The initial treatment had the most FM (16) requiring mitigation development followed closely by treatment planning, segmentation, and plan preparation with fourteen each. The maximum RPN was 400 and involved target delineation.

Conclusion:

The FMEA process proved extremely useful in identifying previously unforeseen risks. New methods were developed and implemented for risk mitigation and error prevention. Similar to findings reported for adult patients, the process leading to the initial treatment has an associated high risk.
MO‐D‐213‐05: Sensitivity of Routine IMRT QA Metrics to Couch and Collimator Rotations
Authors: Alaei P
Published: June 2015

Purpose:

To assess the sensitivity of gamma index and other IMRT QA metrics to couch and collimator rotations.

Methods:

Two brain IMRT plans with couch and/or collimator rotations in one or more of the fields were evaluated using the IBA MatriXX ion chamber array and its associated software (OmniPro‐I'mRT). The plans were subjected to routine QA by 1) Creating a composite planar dose in the treatment planning system (TPS) with the couch/collimator rotations and 2) Creating the planar dose after “zeroing” the rotations. Plan deliveries to MatriXX were performed with all rotations set to zero on a Varian 21ex linear accelerator. This in effect created TPS‐created planar doses with an induced rotation error. Point dose measurements for the delivered plans were also performed in a solid water phantom.

Results:

The IMRT QA of the plans with couch and collimator rotations showed clear discrepancies in the planar dose and 2D dose profile overlays. The gamma analysis, however, did pass with the criteria of 3%/3mm (for 95% of the points), albeit with a lower percentage pass rate, when one or two of the fields had a rotation. Similar results were obtained with tighter criteria of 2%/2mm. Other QA metrics such as percentage difference or distance‐to‐agreement (DTA) histograms produced similar results. The point dose measurements did not obviously indicate the error due to location of dose measurement (on the central axis) and the size of the ion chamber used (0.6 cc).

Conclusion:

Relying on Gamma analysis, percentage difference, or DTA to determine the passing of an IMRT QA may miss critical errors in the plan delivery due to couch/collimator rotations. A combination of analyses for composite QA plans, or per‐beam analysis, would detect these errors.
MO‐DE‐304‐01: The Abt Study of Medical Physicist Work Values for Radiation Oncology Physics Services: Round IV
Authors: Mills M.
Published: June 2015

The Abt study of medical physicist work values for radiation oncology physics services, Round IV is completed. It supersedes the Abt III study of 2008. The 2015 Abt study measured qualified medical physicist (QMP) work associated with routine radiation oncology procedures as well as some special procedures. As before, a work model was created to allow the medical physicist to defend QMP work based on both routine and special procedures service mix. The work model can be used to develop a cost justification report for setting charges for radiation oncology physics services. The Abt study Round IV was designed to empower the medical physicist to negotiate a service or employment contract with providers based on measured national QMP workforce and staffing data.

For a variety of reasons, the diagnostic imaging contingent of AAPM has had a more difficult time trying estimate workforce requirements than their therapy counterparts. Over the past several years, the Diagnostic Work and Workforce Study Subcommittee (DWWSS) has collected survey data from AAPM members, but the data have been very difficult to interpret. The DWWSS has reached out to include more AAPM volunteers to create a more full and accurate representation of actual clinical practice models on the subcommittee. Though much work remains, through hours of discussion and brainstorming, the DWWSS has somewhat of a clear path forward. This talk will provide attendees with an update on the efforts of the subcommittee.

Learning Objectives:

Understand the new information documented in the Abt studies.

Understand how to use the Abt studies to justify medical physicist staffing.

Learn relevant historical information on imaging physicist workforce.

Understand the process of the DWWSS in 2014.

Understand the intended path forward for the DWWSS.
MO‐D‐BRD‐01: Clinical Implementation of An Electronic Brachytherapy Program for the Skin
Authors: Ouhib Z.
Published: June 2015

Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air‐kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir‐192 sources. Consequently, tissue‐specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations.

Learning Objectives:

To understand the basic principles of electronic brachytherapy and the various applications for which it is being used.

To understand the physics of the calibration and commissioning for electronic brachytherapy sources

To understand the unique radiobiology and clinical implementation of electronic brachytherapy systems for skin and IORT techniques

Xoft, Inc. contributed funding toward development of the NIST electronic brachytherapy facility (Michael Mitch).The University of Wisconsin (Wesley Culberson) has received research support funding from Xoft, Inc. Zoubir Ouhib has received partial funding from Elekta Esteya.
MO‐D‐BRD‐04: NIST Air‐Kerma Standard for Electronic Brachytherapy Calibrations
Authors: Mitch M.
Published: June 2015

Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air‐kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir‐192 sources. Consequently, tissue‐specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations.

Learning Objectives:

To understand the basic principles of electronic brachytherapy and the various applications for which it is being used.

To understand the physics of the calibration and commissioning for electronic brachytherapy sources

To understand the unique radiobiology and clinical implementation of electronic brachytherapy systems for skin and IORT techniques

Xoft, Inc. contributed funding toward development of the NIST electronic brachytherapy facility (Michael Mitch).The University of Wisconsin (Wesley Culberson) has received research support funding from Xoft, Inc. Zoubir Ouhib has received partial funding from Elekta Esteya.
MO‐DE‐201‐03
Authors: Fahey F.
Published: June 2015

Fundamental knowledge of radiologic anatomy and physiology is critical for medical physicists. Many physicists are exposed to this topic only in graduate school, and knowledge is seldom formally evaluated or assessed after Part I of the ABR exam. Successful interactions with clinicians, including surgeons, radiologists, and oncologists requires that the medical physicist possess this knowledge. This course presents a review of radiologic anatomy and physiology as it applies to projection radiography, fluoroscopy, CT, MRI, U/S, and nuclear medicine. We will review structural anatomy, manipulation of tissue contrast, the marriage between anatomy and physiology, and explore how medical imaging exploits normal and pathological processes in the body to generate contrast.

Learning Objectives:

Review radiologic anatomy.

Examine techniques to manipulate tissue contrast in radiology.

Integrate anatomy and physiology in molecular imaging.
MO‐DE‐204‐06
Authors: Pelc N.
Published: June 2015

A great deal of progress has been made in iterative/statistical image reconstruction for x‐ray CT, and major vendors have products available for their systems. These image reconstruction algorithms are nonlinear, and therefore present challenges related to image quality evaluation. For example, pixel noise standard deviation is likely not to correlate to perceived image quality and spatial resolution is likely to be contrast dependent. The purpose of this symposium is to inform medical physicists on these challenges and what methods are available for judging image quality and improvements. Following this background, speakers will describe the methods that are available on various commercial systems.

The symposium consists of:

Kyle Myers: “Evaluation of Nonlinear Reconstruction Methods

Karl Stierstorfer: “Advanced Reconstruction Methods on Siemens CT Systems”

Jiang Hsieh: “Advanced Reconstruction Methods on GE CT Systems”

Wenli Wang: “Advanced Reconstruction Methods on Toshiba CT Systems”

Sandra Halliburton: “Advanced Reconstruction Methods on Philips CT Systems”

Panel Discussion

Learning Objectives:

Challenges and methods for evaluating image quality in nonlinear systems

Understand the advanced reconstruction methods available on commercial systems

Understand the benefits provided by the advanced reconstruction techniques

Research support: Philips Healthcare and GE Healthcare
MO‐E‐BRD‐00: Breast Brachytherapy: The Phoenix of Radiation Therapy
Authors: Libby Bruce
Published: June 2015

Is Non‐invasive Image‐Guided Breast Brachytherapy Good? – Jess Hiatt, MS

Non‐invasive Image‐Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real‐time image‐guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary.

Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? ‐ Dorin Todor, PhD VCU

A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi‐catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues.

to review and understand the evolution and development of APBI using brachytherapy methods

to understand the basis and limitations of radio‐biological ‘equivalence’ between fractionation schedules

to review commonly used and proposed fractionation schedules

Intra‐operative breast brachytherapy: Is one stop shopping best?‐ Bruce Libby, PhD. University of Virginia

A review of intraoperative breast brachytherapy will be presented, including the Targit‐A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed.

Learning Objectives:

To review past and current clinical trials for IORT

To discuss lumpectomy‐scan‐plan‐treat workflow for IORT
MO‐PIS‐Exhibit Hall‐4: Toshiba Dose Tracking System: A Paradigm Shift in Patient Dose Monitoring in Fluoroscopically Guided Interventions
Authors: Kuhls‐Gilcrist A.
Published: June 2015

No Abstract provided
MO‐E‐213‐02: Medical Physicist Involvement in Implementing Patient Protection Standards
Authors: Seibert J.
Published: June 2015

The focus of work of medical physicists in 1980's was on quality control and quality assurance. Radiation safety was important but was dominated by occupational radiation protection. A series of over exposures of patients in radiotherapy, nuclear medicine and observation of skin injuries among patients undergoing interventional procedures in 1990's started creating the need for focus on patient protection. It gave medical physicists new directions to develop expertise in patient dosimetry and dose management. Publications creating awareness on cancer risks from CT in early part of the current century and over exposures in CT in 2008 brought radiation risks in public domain and created challenging situations for medical physicists. Increasing multiple exposures of individual patient and patient doses of few tens of mSv or exceeding 100 mSv are increasing the role of medical physicists. Expansion of usage of fluoroscopy in the hands of clinical professionals with hardly any training in radiation protection shall require further role for medical physicists. The increasing publications in journals, recent changes in Safety Standards, California law, all increase responsibilities of medical physicists in patient protection. Newer technological developments in dose efficiency and protective devices increase percentage of time devoted by medical physicists on radiation protection activities. Without radiation protection, the roles, responsibilities and day‐to‐day involvement of medical physicists in diagnostic radiology becomes questionable. In coming years either medical radiation protection may emerge as a specialty or medical physicists will have to keep major part of day‐to‐day work on radiation protection.

Learning Objectives:

To understand how radiation protection has been increasing its role in day‐to‐day activities of medical physicist

To be aware about international safety Standards, national and State regulations that require higher attention to radiation protection than in past

To be aware about possible emergence of medical radiation protection as a specialty and challenges for medical physicists.
MO‐F‐304‐00: PQI
Authors: Jones Aaron
Published: June 2015

With the current Maintenance of Certification (MOC) requirement for a practice quality improvement (PQI) project every 3 years, we all (well, most of us) find ourselves searching for projects that are both manageable and likely to have a positive impact on our clinical practice. In this session we will walk through the use of the Plan, Do, Study, Act (PDSA) cycle to address a common finding in practices where fluoroscopically guided interventions (FGI) are performed: variation in procedural doses among physicians. We will also examine strategies to secure physician support using carrots, not sticks.

Learning Objectives:

Review the PDSA cycle and its application to PQI.

Discuss strategies for action in the example presented.

Examine strategies for successful group PQI projects.

A. Kyle Jones: Owner, FluoroSafety

Joseph R. Steele: Consultant, FluoroSafety
MO‐F‐304‐01: Applying PDSA to a Practical Clinical Problem: Variation in Procedural Doses Among Interventional Radiologists
Authors: Jones A.
Published: June 2015

With the current Maintenance of Certification (MOC) requirement for a practice quality improvement (PQI) project every 3 years, we all (well, most of us) find ourselves searching for projects that are both manageable and likely to have a positive impact on our clinical practice. In this session we will walk through the use of the Plan, Do, Study, Act (PDSA) cycle to address a common finding in practices where fluoroscopically guided interventions (FGI) are performed: variation in procedural doses among physicians. We will also examine strategies to secure physician support using carrots, not sticks.

Learning Objectives:

Review the PDSA cycle and its application to PQI.

Discuss strategies for action in the example presented.

Examine strategies for successful group PQI projects.

A. Kyle Jones: Owner, FluoroSafety

Joseph R. Steele: Consultant, FluoroSafety
MO‐F‐304‐02
Authors: Steele J.
Published: June 2015

With the current Maintenance of Certification (MOC) requirement for a practice quality improvement (PQI) project every 3 years, we all (well, most of us) find ourselves searching for projects that are both manageable and likely to have a positive impact on our clinical practice. In this session we will walk through the use of the Plan, Do, Study, Act (PDSA) cycle to address a common finding in practices where fluoroscopically guided interventions (FGI) are performed: variation in procedural doses among physicians. We will also examine strategies to secure physician support using carrots, not sticks.

Learning Objectives:

Review the PDSA cycle and its application to PQI.

Discuss strategies for action in the example presented.

Examine strategies for successful group PQI projects.

A. Kyle Jones: Owner, FluoroSafety

Joseph R. Steele: Consultant, FluoroSafety
MO‐FG‐BRD‐01: Real‐Time Imaging and Tracking Techniques for Intrafractional Motion Management: Introduction and KV Tracking
Authors: Fahimian B.
Published: June 2015

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam‐level imaging of radio‐opaque fiducials, fiducial‐less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real‐time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam‐level kilovoltage X‐ray imaging techniques, 2) EPID‐based megavoltage X‐ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI‐based soft‐tissue tracking during radiation delivery.

Learning Objectives:

Understand the fundamentals of real‐time imaging and tracking techniques

Learn about emerging techniques in the field of real‐time tracking

Distinguish between the advantages and disadvantages of different tracking modalities

Understand the role of real‐time tracking techniques within the clinical delivery work‐flow
MO‐FG‐BRD‐02: Real‐Time Imaging and Tracking Techniques for Intrafractional Motion Management: MV Tracking
Authors: Berbeco R.
Published: June 2015

Intrafraction target motion is a prominent complicating factor in the accurate targeting of radiation within the body. Methods compensating for target motion during treatment, such as gating and dynamic tumor tracking, depend on the delineation of target location as a function of time during delivery. A variety of techniques for target localization have been explored and are under active development; these include beam‐level imaging of radio‐opaque fiducials, fiducial‐less tracking of anatomical landmarks, tracking of electromagnetic transponders, optical imaging of correlated surrogates, and volumetric imaging within treatment delivery. The Joint Imaging and Therapy Symposium will provide an overview of the techniques for real‐time imaging and tracking, with special focus on emerging modes of implementation across different modalities. In particular, the symposium will explore developments in 1) Beam‐level kilovoltage X‐ray imaging techniques, 2) EPID‐based megavoltage X‐ray tracking, 3) Dynamic tracking using electromagnetic transponders, and 4) MRI‐based soft‐tissue tracking during radiation delivery.

Learning Objectives:

Understand the fundamentals of real‐time imaging and tracking techniques

Learn about emerging techniques in the field of real‐time tracking

Distinguish between the advantages and disadvantages of different tracking modalities

Understand the role of real‐time tracking techniques within the clinical delivery work‐flow
MO‐FG‐BRB‐01: Investing to Address the Global Cancer Challenge
Authors: Atun R.
Published: June 2015

The global burden of cancer is growing rapidly with an estimated 15 million new cases per year worldwide in 2015, growing to 19 million by 2025 and 24 million by 2035. The largest component of this growth will occur in low‐to‐middle income countries (LMICs). About half of these cases will require radiation treatment. The gap for available cancer treatment, including radiation therapy, between high‐income countries (HICs) and LMICs is enormous. Accurate data and quantitative models to project the needs and the benefits of cancer treatment are a critical first step in closing the large cancer divide between LMICs and HICs. In this context, the Union for International Cancer Control (UICC) has developed a Global Task Force on Radiotherapy for Cancer Control (GTFRCC) with a charge to answer the question as to what it will take to close the gap between what exists today and reasonable access to radiation therapy globally by 2035 and what the potential clinical and economic benefits are for doing this. The Task Force has determined the projections of cancer incidence and the infrastructure required to provide access to radiation therapy globally. Furthermore it has shown that appropriate investment not only yields improved clinical outcomes for millions of patients but that it also provides an overall economic gain throughout all the income settings where this investment is made. This symposium will summarize the facets associated with this global cancer challenge by reviewing the cancer burden, looking at the requirements for radiation therapy, reviewing the benefits of providing such therapy both from a clinical and economic perspective and finally by looking at what approaches can be used to aid in the alleviation of this global cancer challenge. The speakers are world renowned experts in global public health issues (R. Atun), medical physics (D. Jaffray) and radiation oncology (N. Coleman).

Learning Objectives:

To describe the global cancer challenge and the corresponding potential benefits of addressing this challenge.

To describe what radiation therapy infrastructure, in terms of facilities, equipment and personnel, will be required to address this challenge.

To describe models of addressing personnel and infrastructure mobilization and capacity building within regions where significant cancer treatment disparities exist.
MO‐FG‐BRB‐04
Authors: Van Dyk J.
Published: June 2015

The global burden of cancer is growing rapidly with an estimated 15 million new cases per year worldwide in 2015, growing to 19 million by 2025 and 24 million by 2035. The largest component of this growth will occur in low‐to‐middle income countries (LMICs). About half of these cases will require radiation treatment. The gap for available cancer treatment, including radiation therapy, between high‐income countries (HICs) and LMICs is enormous. Accurate data and quantitative models to project the needs and the benefits of cancer treatment are a critical first step in closing the large cancer divide between LMICs and HICs. In this context, the Union for International Cancer Control (UICC) has developed a Global Task Force on Radiotherapy for Cancer Control (GTFRCC) with a charge to answer the question as to what it will take to close the gap between what exists today and reasonable access to radiation therapy globally by 2035 and what the potential clinical and economic benefits are for doing this. The Task Force has determined the projections of cancer incidence and the infrastructure required to provide access to radiation therapy globally. Furthermore it has shown that appropriate investment not only yields improved clinical outcomes for millions of patients but that it also provides an overall economic gain throughout all the income settings where this investment is made. This symposium will summarize the facets associated with this global cancer challenge by reviewing the cancer burden, looking at the requirements for radiation therapy, reviewing the benefits of providing such therapy both from a clinical and economic perspective and finally by looking at what approaches can be used to aid in the alleviation of this global cancer challenge. The speakers are world renowned experts in global public health issues (R. Atun), medical physics (D. Jaffray) and radiation oncology (N. Coleman).

Learning Objectives:

To describe the global cancer challenge and the corresponding potential benefits of addressing this challenge.

To describe what radiation therapy infrastructure, in terms of facilities, equipment and personnel, will be required to address this challenge.

To describe models of addressing personnel and infrastructure mobilization and capacity building within regions where significant cancer treatment disparities exist.
MO‐FG‐BRA‐02: Modulation of Clinical Orthovoltage X‐Ray Spectrum Further Enhances Radiosensitization of Cancer Cells Targeted with Gold Nanoparticles
Authors: Wolfe T , Reynoso F , Cho J , Quini C , Cortez M , Manohar N , Krishnan S , Cho S
Published: June 2015

Purpose:

To assess the potential to amplify radiosensitization of cancer cells targeted with gold nanoparticles by augmenting selective spectral components of X‐ray beam.

Methods:

Human prostate cancer cells were treated for 24h with gold nanorods conjugated to goserelin acetate or pegylated, systematically washed and irradiated with 250 kVp X‐rays (25mA, 0.25mm Cu‐ filter, 8x8cm2 field size, 50cm SSD) with or without an additional 0.25 mm Erbium (Er) filter. As demonstrated in a companion Monte Carlo study, Er‐filter acted as an external target to feed Erbium K‐shell X‐ray fluorescence photons (∼50 keV) into the 250 kVp beam. After irradiation, we performed measurements of clonogenic viability with doses between 0 ‐6Gy, irreparable DNA damage assay to measure double‐strand breaks via γH2AX‐foci staining, and production of stable reactive oxygen species (ROS).

Results:

The clonogenic assay for the group treated with conjugated nanoparticles showed radiosensitization enhancement factor (REF), calculated at the 10% survival fraction aisle, of (1.62±0.07) vs. (1.23±0.04) with/without the Er‐filter in the 250 kVp beam, respectively. The group treated with pegylated nanoparticles, albeit retained in modest amounts within the cells, also showed statistically significant REF (1.13±0.09) when the Erbium filter was added to the beam. No significant radiosensitization was observed for other groups. Measurements of ROS levels showed increments of (1.9±0.2) vs. (1.4±0.1) for combined treatment with targeted nanoparticles and Er‐filtered beam. γH2AX‐foci showed 50% increase for the same treatment combination, confirming the enhanced radiosensitization in a consistent fashion.

Conclusion:

Our study demonstrates the feasibility of enhancing radiosensitization of cancer cells by combining actively targeted gold nanoparticles and modulating the X‐ray spectrum in the desired energy range. The established technique will not only help develop strategies to maximize nanoparticle‐mediated radiosensitization but also offer a convenient way to acquire unprecedented insights into the role of photon energy for the observed radiosensitization effects.

Supported by DOD/PCRP grant W81XWH‐12‐1‐0198
MO‐FG‐BRA‐04: Leveraging the Abscopal Effect Via New Design Radiotherapy Biomaterials Loaded with Immune Checkpoint Inhibitors
Authors: Hao Y , Cifter G , Altundal Y , Sinha N , Moreau M , Sajo E , Makrigiorgos G , Ngwa W
Published: June 2015

Purpose:

Studies show that stereotactic body radiation therapy (SBRT) of a primary tumor in combination with immune checkpoint inhibitors (ICI) could Result in an immune‐mediated regression of metastasis outside the radiation field, a phenomenon known as abscopal effect. However toxicities due to repeated systematic administration of ICI have been shown to be a major obstacle in clinical trials. Towards overcoming these toxicity limitations, we investigate a potential new approach whereby the ICI are administered via sustained in‐situ release from radiotherapy (RT) biomaterials (e.g. fiducials) coated with a polymer containing the ICI.

Methods:

New design RT biomaterials were prepared by coating commercially available spacers/fiducials with a biocompatible polymer (PLGA) film containing fluorescent nanoparticles of size needed to load the ICI. The release of the nanoparticles was investigated in‐vitro. Meanwhile, an experimentally determined in‐ vivo nanoparticle diffusion coefficient was employed in analytic calculations based on Fick's second law to estimate the time for achieving the concentrations of ICI in the tumor draining lymph node (TDLN) that are needed to engender the abscopal effect during SBRT. The ICI investigated here was anti‐CTLA‐4 antibody (ipilimumab) at approved FDA concentrations.

Results:

Our in ‐vitro study results showed that RT biomaterials could be designed to achieve burst release of nanoparticles within one day. Meanwhile, our calculations indicate that for a 2 to 4 cm tumor it would take 4–22 days, respectively, following burst release, for the required concentration of ICI nanoparticles to accumulate in the TDLN during SBRT.

Conclusion:

Current investigations combining RT and immunotherapy involve repeated intravenous administration of ICI leading to significant systemic toxicities. Our preliminary results highlight a potential new approach for sustained in‐situ release of the ICI from new design RT biomaterials. These results provide impetus for more studies to leverage the powerful abscopal effect, while minimizing systemic toxicities through the new approach.
MO‐FG‐BRA‐07: Theranostic Gadolinium‐Based AGuIX Nanoparticles for MRI‐Guided Radiation Therapy
Authors: Detappe A , Rottmann J , Kunjachan S , Tillement O , Berbeco R
Published: June 2015

Purpose:

AGuIX are gadolinium‐based nanoparticles, initially developed for MRI, that have a potential role in radiation therapy as a radiosensitizer. Our goal is to demonstrate that these nanoparticles can both be used as an MRI contrast agent, as well as to obtain local dose enhancement in a pancreatic tumor when delivered in combination with an external beam irradiation.

Methods:

We performed in vitro cell uptake and radiosensitization studies of a pancreatic cancer cell line in a low energy (220kVp) beam, a standard clinical 6MV beam (STD) and a flattening filter free clinical 6MV beam (FFF). After injection of 40mM of nanoparticles, a biodistribution study was performed in vivo on mice with subcutaneous xenograft pancreatic tumors. In vivo radiation therapy studies were performed at the time point of maximum tumor uptake.

Results:

The concentration of AGuIX nanoparticles in Panc‐1 pancreatic cancer cells, determined in vitro by MRI and ICPMS, peaks after 30 minutes with 0.3% of the initial concentration (5mg/g). Clonogenic assays show a significant effect (p<0.05) when the AGuIX are coupled with MV photon irradiation (DEF20%=1.31). Similar AGuIX tumor uptake is found in vivo by both MRI and ICPMS 30 minutes after intravenous injection. For long term survival studies, the choice of the radiation dose is determined with 5 control groups (3mice/group) irradiated with 0, 5, 10, 15, and 20Gy. Afterwards, 4 groups (8mice/group) are used to evaluate the effect of the nanoparticles. A Logrank test is performed as a statistical test to evaluate the effect of the nanoparticles.

Conclusion:

The combination of the MRI contrast and radiosensitization properties of gadolinium nanoparticles reveals a strong potential for usage with MRI‐guided radiation therapy.
MO‐FG‐BRA‐09: Quantification of Nanoparticle Heating and Concentration for MR‐Guided Laser Interstitial Thermal Therapy
Authors: MacLellan CJ , Melancon M , Salatan F , Yang Q , Hwang KP , Fuentes D , Stafford RJ
Published: June 2015

Purpose:

Nanoparticle Mediated Laser Interstitial Thermal Therapy (npLITT) is a technique that utilizes tumor localized optically activated nanoparticles to increase the conformality of laser ablation procedures. Temperatures in these procedures are dependent on the particle concentration which generally cannot be measured noninvasively prior to therapy. In this work we attempt to quantify particle concentration in vivo by estimating the increase in R2* relaxation induced by bifunctional magnetic resonance (MR)‐visible gold‐based nanoparticles (SPIO@Au) and relate it to the temperature increase observed during real time MR temperature imaging (MRTI) of laser ablation.

Methods:

SPIO@Au nanoparticles (90nm) were synthesized containing a silica‐iron core (for MR visibility via R2*) and gold shell (for near‐infrared absorption). High resolution R2* maps were acquired before and after injecting four different particle concentrations (saline,1e10, 5e10, and 10e10 particles/mL) into HN5 flank xenografts. Tumors were monitored using MRTI during treatment with an interstitial fiber. (1 watt, 808 nm, 3 minutes)

Results:

The maximum temperature within the tumors increased linearly with concentration of injected particles, reaching 34.0, 37.6, 45.8, and 55.4 ⁰C for saline, 1e10, 5e10 and 10e10 particles/mL injections, respectively (R2=.994). The highest temperatures occur at the injection site rather than the fiber, confirming that SPIO@Au nanoparticles are the primary absorber. The differences between the median R2* measured at the injection site and the rest of the tumor were −6, 134, 111, 156 s‐1 for the saline,1e10,5e10 and 10e10 particles/mL injections, respectively. This R2* change is consistent with the measured relaxivity for the 1e10 particles/mL injection but does not maintain linearity at higher concentrations.

Conclusion:

Bifunctional SPIO@Au nanoparticles are a promising technology for providing noninvasive estimates of particle concentration via MRI and temperature increase in npLITT procedures. Future experiments will focus on lower, physiologically relevant particle concentrations and spin echo R2 mapping to better quantify the particle concentration.

This research was supported by the National Institutes of Health and National Cancer Institute under Award Numbers TL1TR000369 and P30CA016672 and was conducted at the MD Anderson Center for Advanced Biomedical Imaging in‐part with equipment support from General Electric Healthcare.