Introduction of rectosigmoid colectomy improves survival outcomes in early-stage ovarian cancer patients.

Background: To investigate whether rectosigmoid colectomy can improve the prognosis of patients with early-stage ovarian cancer when the ovarian tumor adheres to the rectum.

Methods: We retrospectively studied 210 consecutive patients with stage I/II ovarian cancer treated between 2000 and 2016. The surgical strategy differed between the periods 2000-2007 and 2008-2016 with respect to adhesion between the ovarian tumor and rectum. In the former period, ovarian tumor was exfoliated from the rectum. Only when the residual tumor was apparently observed on the rectal surface after salpingo-oophorectomy with hysterectomy, it was subsequently removed by colorectal surgeons performing rectosigmoid colectomy. In the latter period, the ovarian tumor was resected en bloc with the rectum by performing rectosigmoid colectomy. We compared the progression-free survival (PFS) between the two treatment periods.

Results: Rectosigmoid colectomy was performed more frequently in the latter period than in the former period (43 patients, 31% vs. 6 patients, 8%, p < 0.001). There was no significant difference in complete resection rate between the two periods (97% in the former period, 99% in the latter period, p = 0.278). However, the 5-year PFS rate was significantly higher in the latter period than in the former period (86.0% vs. 74.4%, log-rank test, p = 0.034). Multivariate Cox proportional-hazards regression analysis indicated that disease stage (hazard ratio [HR], 2.87, 95% confidence interval [CI] 1.14-7.34) and treatment period (HR 0.32, 95% CI 0.14-0.73) were independent risk factors for recurrence.

Conclusions: Rectosigmoid colectomy could improve the prognosis of patients with early-stage ovarian cancer when the ovarian tumor adheres to the rectum.