According to a
meta-analysis in the
Cochrane Collaboration, two large trials in Russia and Shanghai found no beneficial effects of screening by breast self-examination "but do suggest increased harm in terms of increased numbers of benign lesions identified and an increased number of biopsies performed." They concluded, "At present, screening by breast self-examination or physical examination cannot be recommended."
[2]
Although breast self-examination increases the number of biopsies performed on women, and thus revenue for the
breast cancer industry[
citation needed], it does not reduce
mortality from breast cancer. In a large clinical trial involving more than 260,000 female Chinese factory workers, half were carefully taught by nurses at their factories to perform monthly breast self-exam, and the other half were not. The women taught self-exam detected more
benign (normal or harmless lumps) or early-stage breast disease, but equal numbers of women died from breast cancer in each group.
[3]
Because breast self-exam is not proven to save lives, it is no longer routinely recommended by health authorities for general use.
[4][5] It may be appropriate in women who have a particularly high risk of developing breast cancer. Some charitable organizations, whose donations depend on promoting fear of breast cancer, still promote this technique as a one-size-fits-all, universal screening approach, even in the low-risk women who are most likely to be harmed by unnecessary invasive follow-up procedures.
[6] Among groups promoting
evidence-based medicine, awareness of
breast health and familiarity with one's own body is typically promoted instead of self-exams.
Wikipedia follow all the links mentioned to get further information on the breast examinations
They alter the normal hormonal cycles thus lead to more chances of mutations