Nonsense Fostered by the British Medical Journal

Harvard professor decries study suggesting breast cancer screenings cause more harm than good

(RxWiki News) The British Medical Journal has recently published a study online suggesting that breast cancer screenings in the UK may cause more harm than good.

This is sheer rubbish says dailyRx Contributing Expert, Daniel J. Kopans, M.D., professor of radiology at Harvard Medical School and senior radiologist - the Breast Imaging Division - Massachusetts General Hospital.

The negative impacts outlined in the report include: false positives (results that appear abnormal but are later found to be normal) and overtreatment - what they describe as "treatment of harmless cancers that would never have caused symptoms or death during a patient's lifetime"

The BMJ report says the screening harms outweigh the benefits for up to 10 years, "after which the benefits accumulate, but by much less than predicted when screening was first started."

Dr. Kopans, who is author of the definitive textbook, Breast Imaging, dozens of book chapters and more than 200 scientific papers, has written the following review of the study.

Nonsense Fostered by the British Medical Journal

by: Daniel J. Kopans, M.D.

Professor of Radiology, Harvard Medical School
Senior Radiologist - Breast Imaging Division - Massachusetts General Hospital

The British Medical Journal's (BMJ) publication policy seems to be "If it is opposed to mammography screening we will publish it no matter how flawed the analysis."

Just a few months ago Professor Kefah Mokbel pointed out that the BMJ had printed a clear lie in a paper claiming that mammography screening led to an increase in mastectomies in the UK when the facts are that women with cancers detected by mammography have a 27% rate of mastectomies while women with clinically evident cancers have almost double the rate at 52%.

Prof Mokbel went on criticize the BMJ for its undisclosed bias against mammography screening citing five other papers in the BMJ that should never have passed peer review due to the fact that they were methodologically nonsense. The risk of publishing scientific nonsense is that others build on that foundation and the house of cards gets taller and taller.

This recent paper by Rafftery and Chorozoglou ("Possible net harms of breast cancer screening:
updated modelling of Forrest report") does exactly that and simply adds to the volume of
misinformation published in the BMJ. The authors reached their negative conclusions using modeling based on work done by Gotzsche whose analyses have been discredited by numerous reviewers.

Recently, in the journal The Lancet, 41 experts in breast health care signed a letter to the editor harshly critical of Dr. Gotzsche and his so called "Cochrane Nordic Center" stating that this group's analyses were "scientifically unsound" forming "an active anti-screening campaign...based on erroneous interpretation of data".

Just as had been done by the recently published Canadian Task Force in developing their screening guidelines Rafferty and Chorozoglou based their negative assessment on the grossly exaggerated rates of overdiagnosis published by Gotzsche and associates. These authors have claimed that as many as 50% of breast cancers found by mammography would "melt away" if left alone despite the fact that there are, virtually, no cases in the modern literature of breast cancers "melting away". Gotzsche's discredited work figures heavily in this latest publication.

Not only did Rafftery and Chorozoglou use the ridiculous overestimates by Gotzsche in their calculations, but they equated the effect on the quality of life of "false positives", with death from breast cancer. At some time you need to get your nose out of the numbers. The vast majority of "false positives" are recalls for additional mammographic images, or ultrasound. A very small percentage of women have a needle biopsy under local anesthesia.

How can these inconveniences and some anxiety be equated with death? The authors also used a decrease in deaths from screening of 15% when it is clear that screening reduces
deaths by at least twice that number.

Overdiagnosis is the purview of pathologists, and overtreatment is being addressed by medical and surgical oncologists. The possibility of overdiagnosis and overtreatment is higher for clinically evident cancers. Should we cease diagnosing and treating these cancers? Therapy has improved over the years, but therapy can only save lives when breast cancers are found early.

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Review Date: 
December 9, 2011