In today’s New York Times, the actress Angelina Jolie published a remarkably forthcoming op-ed about getting a double mastectomy. Jolie carries a variant of a gene called BRCA1 that makes women highly likely to develop breast and ovarian cancer. Her mother, who also carried the variant, died of ovarian cancer at age 56. Like a number of other women with her condition, Jolie decided to get a mastectomy as a preventative measure.

A number of studies have shown that bilateral risk-reducing mastectomies (the official term) do indeed reduce the risk of breast cancer in women with the BRCA1 mutation. In a study published last month in Annals of Oncology, a team of Dutch medical researchers tracked 570