Q. I have heard that women who have a high risk of breast cancer should consider having mastectomies done before cancer is found. Is this really a good idea? How would one decide to take such a radical step?
A. The idea of removing both breasts before cancer develops may seem like an effective, if extreme, prevention strategy. And in some women -- particularly those most likely to develop breast cancer -- such "prophylactic mastectomy" does markedly decrease the risk, although it does not eliminate it altogether.
But before even considering such a radical step, it's important to see whether the woman fits into the "highest risk" category.
Genetic research is shedding light on that question. The highest risk for breast cancer is found in women who have a mutation in the BRCA1 or BRCA2 gene (the gene for breast cancer), a mutation found only in about five percent of all breast cancer patients. Women with this genetic marker have a lifetime risk of greater than 85 percent for developing breast cancer and should be counseled to either have very close follow-up (preferably in the context of a clinical trial) or consider prophylactic mastectomy.
Unfortunately, even with removal of both breasts, microscopic bits of cancer-prone tissue may be left behind. Thus, there is still a very small chance of breast cancer even after removal of both breasts.
The other group of women who may benefit from prophylactic mastectomy are women in whom atypical or "precancerous" cells are already present in both breasts. In some of these women, the anxiety associated with "watchful waiting" and mammography may be too stressful. For these women, prophylactic removal of both breasts may diminish the developing breast cancer, although again, the risk is not completely eliminated.
For most women, even those with a family history of breast cancer, less dramatic options are the better choice. See your doctor regularly, and make sure you and your doctor follow the guidelines set by the American Cancer Society for self-exams, mammography, and follow-up care.