Objective The study aims to identify preoperative predictors of complete cytoreduction and early recurrence and death in epithelial ovarian, tubal, and peritoneal cancer after neoadjuvant chemotherapy (NACT).

Methods We performed a retrospective analysis of 85 patients who underwent 3 cycles of NACT. Patients were divided into 2 groups according to residual tumor at interval debulking surgery (IDS), and clinicopathologic, surgical, and follow-up data were compared.

Results Cancer antigen 125 (CA-125) levels before the IDS after completion of NACT were higher in the residual tumor group (42.0 vs 116.6 U/mL, P = 0.006). The drop rate of CA-125 after NACT was higher in the no residual tumor group (96.8% vs 89.9%, P = 0.001). Patients with residual tumor showed lower disease-free and overall survival outcomes than patients with no residual tumor. In univariate analysis, CA-125 of 100 U/mL or less before IDS and a drop rate after NACT greater than 80% were preoperative predictive factors for complete cytoreduction. In multivariate analysis, a drop rate of CA-125 after NACT greater than 80% was an independent preoperative predictive factor for complete cytoreduction (P = 0.002). Progressive disease on follow-up image during NACT was an independent preoperative predictive factor for early recurrence and death (P < 0.001, both).

Conclusions A significant drop of CA-125 after NACT and progressive disease on follow-up image are independent preoperative predictors for complete cytoreduction and early recurrence and death.