Breast Cancer in Transgender Veterans: A Ten-Case Series.

All known cases of breast cancer in patients with a diagnosis consistent with transgender identification were identified in the Veterans Health Administration (1996-2013). Ten cases were confirmed: seven birth sex females and three birth sex males. Of the three birth sex males, two identified as gender dysphoric male-to-female and one identified as transgender with transvestic fetishism. The birth sex males all presented with late-stage disease that proved fatal, whereas most of the birth sex female transgender veterans presented with earlier stage disease that could be treated. These cases support the importance of screening for breast cancer using standard guidelines in birth sex males and females. Family history of breast cancer should be obtained from transgender people as part of routine care. This report expands the known cases of breast cancer in transgender persons from 5 to 12 (female-to-male) and from 10 to 13 (male-to-female).