Secondary cytoreductive surgery and oncologic outcomes in the era of targeted maintenance therapy for recurrent, platinum-sensitive ovarian cancer.

Objectives: To compare oncologic outcomes of secondary cytoreductive surgery (SCS) before and after FDA approval of Poly(ADP-ribose) polymerase inhibitor (PARPi) and bevacizumab maintenance therapies for platinum-sensitive recurrent ovarian cancer (PS-ROC).

Methods: Patients who underwent SCS for first recurrence of PS-ROC from 1/1/2013-1/1/2020 were identified. Exclusion criteria included prior chemotherapy for recurrence, bowel obstruction procedures, and palliative surgery. Data were dichotomized pre/post 1/2017, relative to FDA approval of PARPi and bevacizumab maintenance for ROC. Second progression-free survival (PFS2), the primary endpoint, was estimated using Kaplan-Meier method.

Results: Overall, 245 patients underwent SCS-131 (53%) pre- and 114 (47%) post-approval. Most patients had high-grade serous tumors (83% and 90%, respectively; p = 0.13). Deleterious BRCA1/2 alterations were identified in 27% (32/120) and 28% (32/113) of tested patients, respectively (p = 0.88). Disease-free intervals pre- and post-approval were: 6-12 months, 16% and 18%; 12-30 months, 56% and 59%; and >30 months, 28% and 24%, respectively (p = 0.73). Overall, 85% and 86% of patients, respectively, achieved complete gross resection (CGR; p > 0.99). PARPi maintenance use increased from 3.8% to 27% (p < 0.001) following approval, and bevacizumab from 1.5% to 12% (p < 0.001). Median PFS2 was 19 and 20.1 months, respectively. In the post group, 1-year PFS2 rate was 84.5% (95% CI, 75.7-90.4%) for patients with CGR vs 56.2% (95% CI, 29.5-76.2%) for those with residual disease; 3-year PFS2 rates were 31.3% (95% CI, 21.6-41.4%) and 12.5% (95% CI, 2.1-32.8%), respectively (p = 0.001).

Conclusions: CGR during SCS is associated with improved PFS2 compared to suboptimal resection. Prospective randomized trials are warranted to elucidate the role of SCS as more therapeutics become available.