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.