A recent study has found that removing the unaffected breast during a double mastectomy does not provide a survival benefit for most women diagnosed with breast cancer in just one breast. The research, published in JAMA Oncology, analyzed data from over 661,000 women and found that the survival rates for those who underwent lumpectomy or mastectomy while keeping their other breast were similar to those who opted for a double mastectomy.

The study revealed that the risk of developing cancer in the other breast is about 7% over 20 years, and having a double mastectomy did not reduce mortality rates associated with the disease. This is attributed to the fact that the primary cause of death is usually due to the spread of cancer from the initially affected breast rather than the development of a new cancer in the other breast.

However, this finding may not apply to women with BRCA1 or BRCA2 gene mutations, who are at a significantly higher risk for breast cancer and might still benefit from a double mastectomy. Despite the lack of survival advantage, some women choose double mastectomy for peace of mind, cosmetic reasons, or to avoid the anxiety of potential future cancers.

Experts emphasize that while a double mastectomy does not improve survival odds, vigilance in screening and effective treatment for the primary cancer are crucial.

Read more about this research in the following NY Times article: Breast Cancer Survival Not Boosted by Double Mastectomy, Study Says - The New York Times (nytimes.com)