Scientists from the Nordic Cochrane Centre in Copenhagen announced the results of a recent study that found breast cancer screening programs helped only one woman out of every 2,000 while harming 10 with false positives and possibly harmful treatments, such as chemotherapy, radiation or mastectomies. The same researchers conducted a study in 2003 that examined the benefits and detriments of self-examination.
A study of nearly 389,000 women from Russia and Shanghai found "no statistically significant difference in breast cancer mortality" between those who self-examined and those who did not. Moreover, the researchers found that unnecessary actions -- such as biopsies -- were twice as common in the self-examination group. The study's results led to some countries classifying breast self-examination as "potentially harmful," and discouraging women from engaging in it.
"We have to rethink the advice we give to the healthy population about cancer," said Peter Gotzsche, MD, director of the Cochrane Centre and the study's lead author. "Some of what we're doing at the moment seems to be quite harmful."
According to Michael Baum, emeritus professor of surgery at University College London and chair of the Psychosocial Oncology Committee at the National Cancer Research Institute, testicular cancer self-examinations can also lead to false positives and harmful treatments.
"There is no data to support the idea that detecting testicular cancer by self-examination improves on the mortality for testicular cancer," said Baum. "Testicular cancer is a relatively rare cancer, whereas testicular lumps are quite common. So if we encourage young men to check their testes, their chances of finding a benign abnormality are considerably more than their chances of detecting cancer."
Baum said testicular cancer false positives are common, and can lead to unnecessary treatments, including surgical removal of a testicle.
Britain's National Health Service defended the practice of breast cancer screening, claiming self-examinations and mammograms save 1,400 lives a year in the UK. A study earlier this year by the Advisory Committee on Breast Cancer Screening found that for every 2,000 women, five had their lives prolonged by screening, while eight received unnecessary treatments.