Outcomes From Opportunistic Salpingectomy for Ovarian Cancer Prevention.

Importance: Opportunistic salpingectomy (OS), which is the removal of fallopian tubes during hysterectomy or instead of tubal ligation without removal of ovaries, is recommended to prevent ovarian cancer, particularly serous ovarian cancer. However, the effectiveness of OS is still undetermined. Objective: To examine observed vs expected rates of ovarian cancer among individuals who have undergone OS. Design, Setting, and Participants: This is a population-based, retrospective cohort study of all individuals in British Columbia, Canada, who underwent OS or a control surgery (hysterectomy alone or tubal ligation) between 2008 and 2017, with follow-up until December 31, 2017. Those with any gynecological cancer diagnosed before or within 6 months of their procedure were excluded. Data analysis was performed from April to August 2021. Exposures: Removal of both fallopian tubes at the time of hysterectomy or instead of tubal ligation while leaving ovaries intact. Main Outcomes and Measures: An ovarian cancer diagnosis listed in the British Columbia Cancer Registry. Age-specific rates of epithelial and serous ovarian cancer in the control group were combined with the specific follow-up time in the OS group to calculate expected numbers (and 95% CIs) of ovarian cancers in the OS group. These were compared with observed numbers. Age-adjusted expected and observed numbers of breast and colorectal cancers were also examined in the OS group. Results: There were 25 889 individuals who underwent OS (mean [SD] age, 40.2 [7.1] years; median [IQR] follow-up, 3.2 [1.6-5.1] years) and 32 080 who underwent hysterectomy alone or tubal ligation (mean [SD] age, 38.2 [7.9] years; median [IQR] follow-up, 7.3 [4.6-8.7] years). There were no serous ovarian cancers in the OS group and 5 or fewer epithelial ovarian cancers. The age-adjusted expected number was 5.27 (95% CI, 1.78-19.29) serous cancers and 8.68 (95% CI, 3.36-26.58) epithelial ovarian cancers. Age-adjusted expected vs observed numbers of breast cancers (22.1 expected vs 23 observed) and colorectal cancers (9.35 expected vs 8 observed) were not significantly different. Conclusions and Relevance: In this cohort study, the OS group had significantly fewer serous and epithelial ovarian cancers than were expected according to the rate at which they arose in the control group. These findings suggest that OS is associated with reduced ovarian cancer risk.