Misinformation and Facts about Breast Cancer Screening

Round 1

Reviewer 1 Report

This is an interesting comment on misinformation on breast cancer screening. Patient should be involved in the medical decision and this kind of papers support this fact. However, I have some comments on this manuscript:

- Introduction: 

Starting the manuscript with a reference to COVID19 I do not think is a good idea, since the characteristics of both facts are completely different and they can not be compared.

Authors describe the most common recommendations on breast cancer screening, and also on the side effects of it. I suggest the authors to include a table showing the available recommendations on screening, their evidence level and the year of updating. 

In addition, authors should include a more detailed description of the adverse effects of screening.

Shared-decision making is a relevant point when asking for a screening test. However, authors did not enter in this point with enough detail. If we want women to be informed, they should include a review of this point including the available tools to support this decision.

 

Author Response

KOPANS response to Reviewer 1

REVIEWER 1: Starting the manuscript with a reference to COVID19 I do not think is a good idea, since the characteristics of both facts are completely different and they can not be compared.

KOPANS: I disagree.  The claims about COVID (eg: “It simply is like the flu”; “Vaccines are dangerous”; We can’t possibly vaccinate everyone”; “Inject bleach..”) had no basis in science, yet they were promulgated as if they were facts even after they were shown to have no scientific support.  The arguments against screening (eg: “Radiation will cause more cancers than can be cured”; “We can’t possibly screen everyone”; “There is massive overdiagnosis”..etc.) have been shown to have little if any scientific merit yet they continue to be promoted and used to discourage women from participating in screening.

REVIEWER 1: Authors describe the most common recommendations on breast cancer screening, and also on the side effects of it. I suggest the authors to include a table showing the available recommendations on screening, their evidence level and the year of updating. 

KOPANS:  I don’t see any value to this.  I have outlined the major guidelines which, essentially, are “Annual screening starting at the age of 40” (the only science and evidence based guideline) and the others (eg: wait until age 45 or wait until age 50 and then screen every two years) which have no basis in science.  This will just take up room and I see no reason to reinforce guidelines that have no scientific foundation.

REVIEWER: In addition, authors should include a more detailed description of the adverse effects of screening.

KOPANS:  I am not sure what the reviewer wants.  The only “adverse effect” that is altered by delaying screening is “recalls for additional evaluation”.  There are varying and multiple adverse effects related to the plethora of treatment options, but these have nothing to do with screening.

REVIEWER 1:  Shared-decision making is a relevant point when asking for a screening test. However, authors did not enter in this point with enough detail. If we want women to be informed, they should include a review of this point including the available tools to support this decision.

KOPANS:  My concern is that there are numerous ways that opponents of screening have tried to belittle screening and emphasize “harms”.  I am writing a book about these.  They cannot possibly fit into this type of review.  For example, there have been a number of studies looking at anxiety related to screening.  Some have claimed persistent anxiety while others have found that they are short lived.  Instead of going through each in detail I have provided references.

Reviewer 2 Report

Thank you for proposing me to review this work.

The author argues that there is misinformation and confusion in the scientific data reaching women and their physicians about the benefits of participating in breast cancer screening. His thesis is that if women uptake the screening programme at age 40 and have annual mammograms they get the most benefit. There is no evidence for using age 50 as a threshold for screening.

The commentary is structured in three parts:

- in the first part (point 2) the author describes in detail how some public health agencies or associations have, over time, modified their criteria for the age at which women should be invited to participate in the breast cancer screening programme, sometimes ignoring the results obtained in scientific studies.

- In the second part (points 3, 4, 5 and 6) the author argues, citing RCTs, observational studies, failure analysis and incidence and prevalence data, the benefits for women's health derived from the implementation of the screening programme.

- In the third section, he denounces the failures in the design and execution of the RCTs of the Canadian National Breast Screening Studies, which failed to demonstrate any benefit from performing mammograms or clinical breast examinations in the screening programme for women aged 40-59 years.

I found it very interesting to learn how the recommended age for joining the screening programme in the USA (and mammograms frequency) has changed over the last decades.

The explanation of the possible mistakes that can be made when designing and implementing an RCT is also very didactic, for which I congratulate the author.

The author makes a strong case for the benefit of starting annual screening mammograms at age 40, as this practice reduces breast cancer mortality. This finding is uncontroversial and well-founded. However, in order for women to be able to make "informed decisions" for themselves about whether or not to participate in screening, they need to be provided with evidence-based and balanced information about the benefits and harms of participation. There is evidence of these harms (Marmot, M., Altman, D., Cameron, D. et al. The benefits and harms of breast cancer screening: an independent review. Br J Cancer 108, 2205–2240 (2013). https://doi-org.sabidi.urv.cat/10.1038/bjc.2013.177), in addition to Gøtzsche PC, Jørgensen KJ. Screening for breast cancer with mammography. Cochrane Database of Systematic Reviews 2013, Issue 6. Art. No.: CD001877. DOI: 10.1002/14651858.CD001877, which the author cites. Some work also attempts to measure how much women's well-being is reduced by overdiagnosis or false positives, and find that they would be willing to accept smaller reductions in mortality to avoid them (for example Sicsic J, Pelletier-Fleury N, Moumjid N. Women’s Benefits and Harms Trade-Offs in Breast Cancer Screening: Results from a Discrete-Choice Experiment. Value Heal. 2018;21(1):78–88.).

In my opinion, the author makes a very good case for the benefits of screening, but downplays the potential harms of breast cancer screening, and this is the main weakness of the commentary. As the author rightly says, women should be able to make an informed decision. Although the magnitude of overdiagnosis, overtreatment and false positives varies greatly between studies, it seems clear that these harms do exist. Therefore, they should be taken into account and women should be informed in a balanced way about all possible consequences of participating in screening.

Finally, with regard to the references, from line 36 onwards, the number does not correspond to the reference in the text. There is also some duplication (e.g. 47 and 86).

Author Response

REVIEWER 2: The author makes a strong case for the benefit of starting annual screening mammograms at age 40, as this practice reduces breast cancer mortality. This finding is uncontroversial and well-founded. However, in order for women to be able to make "informed decisions" for themselves about whether or not to participate in screening, they need to be provided with evidence-based and balanced information about the benefits and harms of participation. There is evidence of these harms (Marmot, M., Altman, D., Cameron, D. et al. The benefits and harms of breast cancer screening: an independent review. Br J Cancer 108, 2205–2240 (2013). https://doi-org.sabidi.urv.cat/10.1038/bjc.2013.177), in addition to Gøtzsche PC, Jørgensen KJ. Screening for breast cancer with mammography. Cochrane Database of Systematic Reviews 2013, Issue 6. Art. No.: CD001877. DOI: 10.1002/14651858.CD001877, which the author cites. Some work also attempts to measure how much women's well-being is reduced by overdiagnosis or false positives, and find that they would be willing to accept smaller reductions in mortality to avoid them (for example Sicsic J, Pelletier-Fleury N, Moumjid N. Women’s Benefits and Harms Trade-Offs in Breast Cancer Screening: Results from a Discrete-Choice Experiment. Value Heal. 2018;21(1):78–88.).

KOPANS:  It would be impossible for me to detail all the misinformation that has been provided over the decades in the limited space available.  For example, the Cochrane “Review”, suggested above by Reviewer 2, has been severely criticized for not adhering to science and, instead, promoting the biases of the authors.  The mere fact that the “risks” of screening have been called “harms” is pejorative.  I am writing a book that documents and addresses all the misinformation that has been promulgated in an effort to reduce access to screening.  I cannot possibly address and detail all of this in the space allotted.

REVIEWER 2:  In my opinion, the author makes a very good case for the benefits of screening, but downplays the potential harms of breast cancer screening, and this is the main weakness of the commentary. As the author rightly says, women should be able to make an informed decision. Although the magnitude of overdiagnosis, overtreatment and false positives varies greatly between studies, it seems clear that these harms do exist. Therefore, they should be taken into account and women should be informed in a balanced way about all possible consequences of participating in screening.

KOPANS: The point is that the “harms” (such as “overdiagnosis”) have been grossly overexaggerated.  I have stated that the only “harm” that is reduced by delaying screening is “recalls” and I have addressed this.  “Overdiagnosis” is likely minimal if at all.   “Overtreatment” is not the fault of screening.

REVIEWER 2:  Finally, with regard to the references, from line 36 onwards, the number does not correspond to the reference in the text. There is also some duplication (e.g. 47 and 86).

KOPANS:  I will correct the references.

Reviewer 3 Report

Dear authors  

the topic is very important and relevant. You can improve your article with a topic about most  pathologies and the prevalence. Also you need to write about screening in younger people with family incidence.

 

best regards 

Author Response

REVIEWER 3 the topic is very important and relevant. You can improve your article with a topic about most  pathologies and the prevalence. Also you need to write about screening in younger people with family incidence.

KOPANS:  My goal was to cover the main issues within a reasonable space.  I am not sure what “most pathologies and the prevalence” would add.

The defense of screening is based on the Randomized Controlled Trials and there are no RCT for women under the age of 39 or over the age of 74.  I can speculate as have others, but my point is that “speculation” has resulted in major pieces of misinformation.  Once the science is accepted then we can  speculate on expanding the guidelines.

Reviewer 4 Report

This is a very ambitious, comprehensive overview of the history of breast cancer screening which also counterbalancing the anti-screening "arguments". The paper is very well written. I have made a few small suggestions in the text (see the attached text), mostly for helping the reader to understand that the emphasis is on "early detection", not on the term "screening", since, unfortunately, there are poor screening programs (the most infamous one is detailed well in this paper). The benefit arrive from participating in high quality screening, through which "early detection", leads to decrease in the absolute numbers of advanced breast cancers, suffering from the disease and decrease in BC death. 

Comments for author File: Comments.docx

Author Response

I agree with the reviewer and accept the suggested changes.

Round 2

Reviewer 1 Report

I agree with the final version.