Is hormonal therapy after risk-reducing salpingo-oophorectomy associated with an increased risk of malignancy in pathogenic variant carriers?

Objectives: This study aimed to assess the association between hormone replacement therapy and the incidence of subsequent malignancies in patients who underwent risk-reducing salpingo-oophorectomy and had mutations predisposing them to Müllerian cancers. Methods: This Institutional Review Board-approved retrospective study was performed at five academic institutions. Women were included if they were age 18–51 years, had one or more confirmed germline highly penetrant pathogenic variants, and underwent risk-reducing salpingo-oophorectomy. Patients with a prior malignancy were excluded. Clinicodemographic data were collected by chart review. Patients with no documented contact for one year prior to study termination were called to confirm duration of hormone use and occurrence of secondary outcomes. Hormone replacement therapy included any combination of estrogen or progesterone. Results: Data were analyzed for 159 women, of which 82 received hormone replacement therapy and 77 did not. In both groups an average of 6 years since risk reduction had passed. The patients treated with hormone replacement therapy did not have a higher risk of subsequent malignancy than those not treated with hormone replacement therapy (6 out of 82 vs. 7 out of 77, P = .68). Patients who received hormone replacement therapy were younger than those who did not receive hormone replacement therapy (39.0 vs. 43.9 years, P < .01) and were more likely to have undergone other risk reductive procedures including mastectomy and/or hysterectomy, though this difference was not statistically significant (69.5% vs. 55.8%, P = .07). Conclusions: In this multi-institution retrospective study of data from patients with high-risk variant carriers who underwent risk-reducing salpingo-oophorectomy, there was no statistically significant difference in the incidence of malignancy between women who did and did not receive hormone replacement therapy.