Risk-reducing Salpingo-Oophorectomy in Women at Higher Risk of Ovarian and Breast Cancer: A Single Institution Prospective Series.

Background/aim: Occult cancers' reported rates vary from 2-12% and serous tubal intraepithelial carcinomas (STICs) have been identified in 3-12% of the prophylactically removed tubes of women carrying a BRCA mutation. The aim of this study was to evaluate the incidence of tubal minor epithelial atypia (STIL), STIC, and occult invasive cancer and to evaluate the cancer-specific mortality in a prospective series of women at higher risk of ovarian and breast cancer undergoing risk-reducing salpingo-oophorectomy (RRSO) n a tertiary cancer center.

Patients And Methods: A series of RRSO specimens (including endometrial biopsy) from women carrying a BRCA mutation, BRCA-unknown and BRCA-negative were collected between January 1998 and April 2016 at the Division of Gynecology at the European Institute of Oncology. Inclusion criteria were: asymptomatic women who had a negative gynecologic screening within 3 months prior to RRSO. Exclusion criteria were: women with ovarian/tubal cancer prior to RRSO.

Results: A total of 411 women underwent RRSO. Median age at RRSO was 47.0 years (range=32-70 years); 75.2% had a history of breast cancer. Fifteen women were diagnosed with an occult cancer (7 STIC, 4 invasive cancers, 2 breast cancers metastatic to the adnexa, 2 endometrial cancer) (3.6%). Sixteen showed a STIL (3.9%). When excluding cases with preoperative positive markers, the occult invasive cancer rate drops to 1.5%.

Conclusion: Our study, covering an 18-year period, shows a substantial low risk of occult cancer among a high-risk population of women undergoing RRSO. Our data still support the indication for RRSO in higher-risk patients. An endometrial biopsy should also be routinely obtained as it raises the chances of detecting occult endometrial cancers that may be otherwise missed.