Platinum-rechallenge in epithelial ovarian cancer relapsing within 6 months after first-line treatment: a propensity score matching analysis
Prognosis for patients with early platinum-resistant Epithelial Ovarian Cancer (EOC) relapse after first-line chemotherapy remains poor. This study explores whether platinum rechallenge may be an option in this setting. In this retrospective, single-institute, observational study, we enrolled BRCA1/2 wild-type (BRCAwt) patients who underwent surgery (January 2017-July 2021) and relapsed within 6 months after first-line platinum-based chemotherapy. Platinum (P) rechallenge was compared with pegylated liposomal doxorubicin (PLD) or non-platinum/non-PLD therapy (weekly paclitaxel/gemcitabine/topotecan, PGT). To minimize selection bias, propensity score matching (PSM) analysis was performed. Overall, 87 patients were identified: 18 (20.7%, P cohort), 50 (57.5%, PLD cohort) and 19 (21.8%, PGT cohort); after PSM, 54/87 patients were identified with similar characteristics, 18 for each group. Grade 3/4 toxicity events were more frequent in P group patients (13/18, 72.2%), compared to PDL (5/18, 27.8%) and PGT (7/18, 38.9%)(PvsPDL: p = 0.008; PvsPGT: p = 0.044; PDLvsPGT: p = 0.479; PvsPDLvsPGT: p = 0.021). Median progression-free survival (mPFS) was 9 months (P cohort) (CI 95%; 4.842-13.158), achieving a 4-month and 3-month increase compared to PLD (mPFS 5 months, p < 0.002) and PGT group (mPFS 6 months, p < 0.05), respectively. Median overall survival (mOS) benefit was preserved: 32 months (P cohort) compared to PLD (13 months, p = 0.001) and PGT (18 months, p = 0.01) groups. On multivariate analysis, platinum rechallenge was an independent prognostic factor for PFS (HR: 0.416; 95% CI: 0.215-0.807; p = 0.009) and OS (HR: 0.175; 95% CI: 0.061-0.503; p = 0.001). Results were consistent with the whole population. Platinum rechallenge showed promising survival outcomes for BRCAwt patients recurring within 6 months after first-line platinum-based chemotherapy.