The number of women undergoing double mastectomy to prevent breast cancer has tripled in the last decade, even though the data [over decades] comparing women who underwent breast-conserving surgery and mastectomy and the survival was exactly the same.
Although many women with breast cancer have chosen to have both breasts removed, rather than just the one with cancer, to reduce the risk of recurrence, data do not show whether lives have been saved with the preventive procedure.
Double mastectomies have become more common since Angelina Jolie opted for one in 2013, but were already on the rise as more women undergo genetic testing after breast cancer diagnosis.
For the study, published in the Annals of Surgery, researchers identified 496,488 women in the Surveillance, Epidemiology and End Results registry diagnosed between 1998 and 2012 with stage 1 to stage 3 breast cancer, analyzing their surgical choice and improvement in cancer condition.
Of the women diagnosed with unilateral invasive breast cancer, 59.6 percent had breast-conserving surgery, 33.4 percent had unilateral mastectomy and 7 percent had a preventive double mastectomy. The proportion of women having double mastectomies has increased overall from 3.9 percent in 2002 to 12.7 percent in 2012.
The researchers found, despite the high rates of surgery, and increase in double mastectomies, that 10-year survival rates remained about the same for all three surgical groups at 91.8 percent for those having breast-conserving surgery, 83.8 percent for unilateral mastectomy and 90.3 percent for a double mastectomy.
