OV21/PETROC: A randomized Gynecologic Cancer Intergroup (GCIG) phase II study of intraperitoneal (IP) versus intravenous (IV) chemotherapy following neoadjuvant chemotherapy and optimal debulking surgery in epithelial ovarian cancer (EOC).

LBA5503Background: The aim of this 2 stage randomized trial was to evaluate whether women undergoing neoadjuvant IV chemotherapy followed by delayed debulking surgery benefit from the addition of IP/IV treatment after surgery. Methods: Stage 1 was a randomized 3-arm design including 2 IP platinum regimens: 153 women who received 3-4 courses of IV platinum-based chemo for stage IIB-III (IV pleural effusion only) EOC followed by optimal debulking surgery ( < 1 cm) were randomized to: ARM1 D1 IV paclitaxel (pacli) 135mg/m2 + IV Carboplatin AUC 5/6 with d8 pacli IV 60 mg/m2 Q 21d X3; ARM 2 D1 IV pacli 135mg/m2 + IP cisplatin (Cis) 75 mg/m2 and d8 IP pacli 60 mg/m2 Q21d X3; or ARM 3 d1 IV pacli 135mg/m2+ IP Carboplatin AUC 5/6 and d8 IP pacli 60mg/m2 Q21dX3. A planned DSMC review confirmed dropping ARM2 (IP cis) and continuing study as an expanded phase II comparing 200 patients randomized to ARMs 1 and 3, which has 80% power to detect a 19% difference in progression rate at 9 mo (PD9, primary endpoint), 2-sid...