Failure of early interval debulking surgery after standard neoadjuvant chemotherapy: May bevacizumab add something? A large retrospective study

Abstract

Introduction

Data are limited on the use of bevacizumab in neoadjuvant setting for High-Grade Serous ovarian Cancer (HGSC) patients. This study explores the effect of adding bevacizumab to standard neoadjuvant chemotherapy (NACT) following the failure of early Interval Debulking Surgery (eIDS).

Materials and methods

This monocentric study retrospectively enrolled FIGO stage IIIC-IV HGSC patients (2017–2021), persisting unresectable after three NACT cycles. Eligible patients had an ECOG performance status ≤2, were aged 40–75 years, and had no contraindications to bevacizumab administration. Patients were stratified whether they added bevacizumab from cycles 4 to 6 (CPB group) or not (CP group). The primary endpoint was the cytoreduction rate after six cycles (delayed IDS, dIDS).

Results

Overall, 58(23 %) patients received neoadjuvant bevacizumab(CPB), and 190 (77 %) did not (CP). Delayed IDS was performed in 117(47.6 %) patients (CPB:31–53.4 %; CP:86–45.8 %; p = 0.38), with complete gross resection rates of 83.9 % and 88.5 %, respectively (p = 0.72). Severe postoperative complications were comparable (CP: 8 %, CPB: 9.7 %, p = 0.069). Median overall survival (OS) for dIDS patients showed no significant difference (CPB: not reached, CP:38 months, p = 0.55), nor did progression-free survival (PFS; CPB:14 months, CP:12 months, p = 0.830). Conversely, among 130(52 %) patients persisting unresectable, bevacizumab significantly improved OS in the CPB group (not reached vs.18 months, p = 0.015), although PFS remained similar (CPB: 6 months, CP: 7 months, p = 0.741).

Conclusion

While adding bevacizumab to NACT does not seem to increase the dIDS rate, it significantly extends OS in unresectable patients. Its use may be a valuable option in selected cases after eIDS’ failure.