I have just listened to an interview on Woman’s Hour with Prof Peter Gotzsche of the Nordic Cochrane Centre in Copenhagen. I have talked about the value of screening by mammogram in previous posts. In his research, Prof Gotzsche has concluded that screening women by mammogram does not increase the length of time they live, which is ultimately what women are concerned about when they are diagnosed with cancer. His research has shown that since screening has been introduced more cancers are being detected but death rates are not coming down. Some cancers are dangerous and some are not but it is impossible to distinguish between the two.
Here are some other interesting studies:
Dr. Laura Esserman published the most powerful and important of these articles in the Journal of the American Medical Association in 2009. Dr. Esserman and her colleagues explore U.S. public health data, and point out hard truths. For starters they note that cancer diagnoses increased, and never came back down, after mammography screening was introduced. This is not minor. An effective screening test shouldn’t increase cancer diagnoses. It should allow doctors to find the same cancers, but earlier. There may be a bump when screening begins, but the numbers should soon return to their baseline. Mammograms, however, permanently increased these numbers, which means they identify ‘cancers’ that never would have been found. That’s not early detection, that’s extra detection.
This would be fine if the extra detection came with a life-saving benefit, i.e. if the dangerous cancers were being found early enough to make a life-saving difference. But Esserman points out that deaths never dropped (as they should have) after the introduction of mammography.
Less than a year after the Esserman paper, a study published in the New England Journal of Medicine reported breast cancer mortality statistics from Norway before, during, and after the introduction of mammography. Norway’s experience is notable because they used mammography in selected regions only. Breast cancer deaths dropped where mammography was phased in. Encouraging. But deaths also dropped where mammography wasn’t available, and the drop was of equal magnitude. This strongly suggests that breast cancer treatments, and not mammography screening, were responsible for the decrease.
It can be said that mammography is still valuable as a diagnostic tool when a lump or abnormality has been found but not for routine screening.
Prof Gotzsche also questioned the value of self-examination as it does not appear to make any difference to a woman’ s survival chances. Obviously, I promote the benefits of women checking their breasts on a monthly basis and so I will continue to investigate this further.
Nikki Mattei – Healthy Breasts For Every Woman Campaign
