CYP19A1 and breast cancer: During the last decades, dysfunction of sexual and vaginal health, including genitourinary syndrome of menopause (GSM), has remained underdiagnosed and undertreated in survivors of breast cancer.1,2 These symptoms are usually worse among survivors of breast cancer compared with women without history of cancer, due to the antiestrogenic effects of chemotherapy, tamoxifen, and aromatase inhibitors.3 In addition, estrogen-based standard treatment for GSM remains controversial in this subset of patients.4