Reviewer's report
Title:Mammography-based screening program: preliminary results from a first,
2-year round in a Brazilian region using mobile and fixed units
Version: 1Date:22 May 2012
Reviewer: Alfonso Frigerio
Reviewer's report:
8002280170426954_article
Mammography-based screening program: preliminary results from a first, 2-year
round in a Brazilian region using mobile and fixed units
Authors:
Raphael Luiz Haikel Juniora, MD, MBA, PhD;
Edmundo Carvalho Mauada, MD, MBA, PhD;
Thiago Buosi Silvaa, BSc, MSc;
Jacó Saraiva de Castro Mattosa, MD, PhD;
Luciano Fernandes Chalab,MD, PhD;
Adhemar Longatto-Filhoc,d, MSc, PhD, PMIAC;
Nestor de Barros, MD, PhDe
Revision by Alfonso Frigerio
1. Is the question posed original, important and well defined?
The research question posed by the authors is easily identifiable and understood.
The originality lies in reporting an experience from a country where no
large-scale organized breast-screening programme has been set up, to date, and
especially in addressing the point of using Mobile Units as an organizational
strategy tailored to the special context.
As to conclusions of the study, I would make some suggestions (see below).
2. Are the data sound and well controlled?
Data seem sound and controlled. I do suggest however that more details could
be provided and Tables inserted to summarize results.
3. Is the interpretation (discussion and conclusion) well balanced and supported
by the data?
All in all, interpretation looks well-balanced. I have a number of minor revisions
that I suggest below, though.
4. Are the methods appropriate and well described, and are sufficient details
provided to allow others to evaluate and/or replicate the work?
More details about results would be welcome, as well as Tables, as already
suggested (see comments below).
5. What are the strengths and weaknesses of the methods?
I do not see major limitations, apart from what already expressed.
6. Can the writing, organization, tables and figures be improved?
Yes, definitely, Either I missed a portion of the material provided, or there are no
Tables summarizing results (see above). I believe that there may be some
weaknesses here and there in the English text. However, English not being my
mother tongue, I would leave adjustments, if needed, to the editorial team.
7. When revisions are requested.
Some data and tables would be welcome in order to better support the authors'
conclusions and to improve the clarity of the paper.
8. Are there any ethical or competing interests issues you would like to raise?
No special comments here.
Here follow some comments/suggestions of mine that might be mostly
considered as minor essential revisions, apart from the production of Tables,
which should be strongly recommended.
Mammography-based screening program: preliminary results from a first, 2-year
round in a Brazilian region using mobile and fixed units
Haikel et al
p.2
ABSTRACT
Background: Breast cancer is the most frequently diagnosed cancer and the
leading
cause of cancer deaths among women _
where? Do the Authors refer to Brazil, to their region, or to the world situation?
Methods: Based on epidemiologic-based data, 54 238
women, aged 40 to 69 years, were eligible for breast cancer screening
Results: Overall, 17 964 women underwent mammography. This represented
33.1% of eligible women in the area. Averages of 18.6 and 26.3 women per day
were examined in the FU and MU, respectively. Seventy-six patients were
diagnosed with breast cancer (41 in the MU, or 54%). This
represented 4.2 cases of breast cancer per 1000 examinations
---question: what is the underlying incidence of BC in these regions?
p.4
The global survival rates are 73% in developed countries and 57% in developing
countries[4].
---one should state the survival term, ie 5-ys or 10-ys survival rates?
Mammography is accepted worldwide as the first option for breast cancer
screening. […] However, the effectiveness of these programs remains to be
evaluated[5].
---both the concept and the reference appear questionable: many published trails
on screening, most notably the Swedish 2county trial (your ref. 13 and 14, by
Tabar and Duffy – that I would quote at this point), made use of MU and
demonstrated the effectiveness of mammography screening and the feasibility of
use of MU; the Florence project in ref. 5 reports results from an urban project that
also made use of MU. I would re-phrase the concept: one might state that:
1. breast cancer screening with mammography has proved effective in reducing
BC mortality in a number of studies and this is the reason why mammography
screening is the standard option worldwide for early detection of BC (this is
mentioned, with refs later on, yet I would state this firmly at this point, and
anticipate the relevant refs)
2. some programs have produced good reports of the effective use of MU as well
as that of FU in screening, depending on organizational/geographic situations
(your ref. 13 and 14, by Tabar and Duffy – could be quoted at this point)
3. the authors are interested in proving that the use of MU is feasible and works
well in the Brasilian setting of the region involved
Thus, opportunistic screening lacks some important requirements for
effectiveness,
including eligibility parameters, quality assurance of the technical proceedings,
follow-up of positive test results, and program evaluation[6].
I suggest to include at this point a statement highlighting that:
“Most notably, opportunistic screening lacks the population perspective, ie the
proper setting and organization that is needed for aiming at the mortality
reduction in the general population”
This sentence links finely to the ensuing original text.
p.5
Recently, convincing evidence has suggested that organized screening could
effectively reduce breast cancer mortality[13-15].
If the evidence was convincing, then it should have “demonstrated that etc” or “
suggested that organized screening can etc” or, maybe better still (possible
re-phrasing):
“Recent convincing evidence has shown that organized screening can effectively
reduce breast cancer mortality[13-15].”
p.7
Classification report
The Breast Imaging-Reporting and Data System (BI-RADS) was used to
classify findings in the mammograms[17]. The BI-RADS 1 and BI-RADS 2
classifications were considered a normal mammogram, and no further action was
taken. In these screening exams, the BI-RADS 3 classification was not
considered to
require further examination. In contrast, the BI-RADS 4 and BI-RADS 5
classifications
required referrals for further examination.
This part is OK.
[Just one collateral consideration: the BI-RADS was devised in the US for
settings other than organized screening. “BI-RADS 3” imply short term follow-up
which is not feasible, nor recommended in organized screening. The Radiological
Classification in the “European Guidelines for Breast Cancer Screening – 6th
Ed., De Wolf et al, 2006” would probably be preferable in a screening setting. It
involves 5 categories R1-5. Among the European categories, the “BI-RADS 2”
would be included in the European “R2” and require no further action, as in the
present paper. The European “R3” is similar to “BI-RADS 4a” and does require
further assessment.]
women with no neoplastic lesions were followed according to hospital guidelines
do you mean “operated women, with no neoplastic lesions”?
and then, why not refer them back to regular screening, if they had no cancer?
p.8
Results
I would strongly recommend to produce and insert Tables to summarize results
The histological analysis identified the different types of breast cancer;
these included invasive ductal carcinoma (72.4%), invasive lobular carcinoma
(17.1%) and ductal carcinoma in situ (10.5%).
Suggestion: it seems preferable, in accordance with usual reports and guidelines,
to separate “invasive cancers detected” from “in situ carcinomas”, then to define
different subtypes among the invasives. So it could be (suggested text):
“Of all cancers detected, based on histological analysis, 89.5% were invasive
and carcinoma in situ accounted for the remaining 10.5%. Of the invasive cases,
80.9% were invasive ductal carcinoma and 19.1% were lobular invasive
carcinomas. [my own calculations, to be checked]”
[However, it seems too simple to retrieve only IDCs and ILCs; one should expect
also other, though less frequent, subtypes such as Tubular invasive carcinoma,
Mucinous/colloid carcinoma, Medullary carcinoma, Papillary carcinoma etc. I
wonder whether these were recorded and I suggest that a specification of (at
least) “Other histological subtypes” were detected in xy%.]
p.10
Participation is naturally a strong predictor of the program’s impact
Participation is not a predictor of the program’s impact: it is a pre-requisite of
impact.
That is: if you run a high quality program with low participation you will expect
negligible results at the population level; however if you run a programme with
high participation and low quality, you are not predicting any significant decrease
in mortality.
p.13
the results suggested that it would be prudent to initiate mammographic
screening in relatively young women. This would optimize the detection of
incipient
tumors
that is arguable: I tried to calculate the exact figures from the sparse data
provided (again: we need tables with complete details). If I am right, there were
21 cancers detected both in the 50-59 and in the 60-69 age group, consistent
with a roughly double detection rate in the older women group. I could not
understand from the article in what age group the advanced cancers were most
represented. Though, it appears that spontaneous mammography among the
younger women might be more diffuse in the population, so that a choice in
favour of screening younger persons would leave the 60+ age group to a
situation of late diagnosis. But then one should also consider what is life
expexctancy in Brasil beyond 69 ys, which I do not know.
p.14
but the MU was more widely accepted by the examined women.
… Or: “The MU in fact answered an underlying need of the population resident in
the rural areas more than the FU did with respect to the urban population, that
was already partially covered by opportunistic screening outside the programme.”
p.14-15
In the present study, the recall rate of screening was 9.4%, consistent with
internationally recommended values of around 10%[24]. The Breast Cancer
15
Surveillance Consortium of the U.S. National Cancer Institute; the national breast
cancer early detection program of the U.S. Centers for Disease Control and
Prevention; and the UK National Health Service Breast Screening Program had
recall
rates of 13.1%, 11.2%, and 7.4%, respectively, for the first round of
screening[45].
I would state that “recall rate of 9.4% was slightly above the 7% recall rate that is
most commonly recommended in population-based programs as the upper
acceptable limit for the first screening round” (see: European Guidelines for
Breast Cancer Screening). The US quoted values (above 10%) are from settings
different from organized, population-based screening programmes.
p.15
This may have been because they had no specific
training in breast radiology;
At this point I would insert a remark such as “The issue of professional training of
medical and technical personnel in the assessment units of the screening
programmes should be among the priorities to consider in the further
development of this project”.
p.16-17
In addition, there was a high demand for
mammography in the region, which was confirmed by the high number of
referrals
from doctors for early detection screening. Consequently, the overall problem
was
large, due to the lack of a health policy priority system for mammographic
screening.
17
The early detection program described here was functional and provided
acceptable results. The MU approach offers potential for progressive
improvement
in early detection of breast cancer.
The above conclusions look OK to me. However, my suggestion would be to add
a further final comment stating something similar to:
“Our findings support the idea that it would thus be advisable to plan and set up a
comprehensive, population-based breast screening project in the age-group
40-69 in our region. This should include the implementation of a monitoring
system based on the complete registration of all breast cancer cases in the target
population, both symptomatic and asymptomatic, diagnosed both within the
screening units and through other diagnostic facilities. Also, a high quality,
specific training should be required to all professionals involved in the execution,
interpretation and diagnostic work-up of screening mammographies.”