Neoadjuvant Chemotherapy Followed by Maintenance Therapy With or Without Bevacizumab in Unresectable High-Grade Serous Ovarian Cancer: A Case-Control Study

Objective. The aim of this study was to compare the toxicity, perioperative outcomes of interval debulking surgery (IDS), and duration of progression-free survival (PFS) in women with unresectable high-grade serous advanced ovarian cancer (AOC) receiving neoadjuvant chemotherapy (NACT) with or without bevacizumab. Methods. Twenty-five patients with high-grade serous AOC treated with bevacizumab-based NACT (cases) were matched according to initial disease extension assessed by laparoscopy, and age, in a 1: 2 ratio, with 50 high-grade serous AOC patients treated with standard NACT without bevacizumab (controls). Results. Both groups received a median of four NACT cycles before IDS (p = 0.867), and the median time interval between NACT and IDS was 27 days in both groups (p = 0.547). Twenty-two cases (88.0 %) showed complete/partial radiologic response compared with 36 controls (72.3 %; p = 0.054). A higher percentage of cases showed complete serological response (48 vs. 35.1 %; p = 0.041). At IDS, complete cytoreduction was achieved in 20 cases (80.0 %) and 36 controls (72.3 %) [p = 0.260]. No differences were observed between groups in terms of surgical complexity score, perioperative outcomes, surgical complications, and chemotherapy-related adverse events. One death due to gastrointestinal perforation was observed among cases. Cases showed a longer median PFS compared with controls (18 months vs. 10 months; p = 0.001), and the administration of bevacizumab (hazard ratio 3.786; p = 0.001) retained a prognostic role for longer PFS at multivariate analysis. Conclusions. The incorporation of bevacizumab in NACT prolongs PFS without affecting the safety of IDS. The risk of gastrointestinal perforation should be considered prior to attempting bevacizumab-based NACT in women with diffuse bowel involvement at initial laparoscopic evaluation.