Exploring PIPAC for managing platinum resistant and refractory ovarian cancer with peritoneal spread: A collaborative multi-institutional study

Background: Platinum-resistant or refractory epithelial ovarian cancer (EOC) remains a significant clinical challenge, often leading to rapid progression and poor prognosis. Palliative treatments aimed at improving quality of life are warranted. Objective: To assess the feasibility and potential benefits of Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) in patients with platinum-resistant or refractory EOC. Methods: Prospective multicenter observational study (2016–2023). Primary endpoint: feasibility, defined as completion of ≥3 planned PIPAC cycles within 120 days without ≥ grade 3 treatment related adverse events (CTCAE v5.0). Secondary endpoints: safety; disease control (RECIST 1.1); changes in Peritoneal Cancer Index and Fagotti score; ascites control; CA-125 response; conversion to cytoreductive surgery (±HIPEC); and overall survival (OS). Results: Forty patients were enrolled. Ninety-seven percent of procedures were completed. Feasibility was 65.0 % (26/40; 95 % CI 49.51–77.87); no grade ≥3 events occurred. Key secondary outcomes included a clinical benefit rate of 35 % in the intention-to-treat (ITT) population and 53.8 % in the per-protocol (PP) population, median time to ascites resolution of one cycle, and median overall survival of 14 months (17 months in PP). Higher white blood cell count and ascites volume were significantly associated with progression (p = 0.035 and p = 0.025). Three platinum-refractory patients became eligible for surgery, two underwent optimal cytoreduction. Median OS was 14 months (17 months in PP). A non-significant trend toward longer OS was observed in platinum-refractory versus platinum-resistant disease (18 vs 9 months; p = 0.093). Conclusions: PIPAC is a feasible, well-tolerated option in platinum-resistant and refractory EOC with potential to stabilize disease, relieve ascites and enable surgery in selected cases.