Hyperthermic intraperitoneal chemotherapy (HIPEC) after primary debulking surgery in advanced epithelial ovarian cancer: Is BRCA mutational status making the difference?

Introduction: The role of a molecular pattern predictive of hyperthermic intraperitoneal chemotherapy (HIPEC) efficacy in advanced ovarian cancer (AOC) patients has been poorly investigated. We aimed to assess the effect of HIPEC after primary debulking surgery (PDS) in AOC according to patient's Breast Cancer Gene (BRCA) mutational status. Methods: This is a retrospective, single center, case-control study. Data on AOC patients receiving HIPEC at the end of PDS as previously enrolled in a phase II monocentric trial (HIPEC group), were retrieved and matched for clinical and surgical characteristics with a group of cases who underwent PDS without receiving HIPEC between 01/2010 and 01/2015 (No HIPEC group). Patients with International Federation of Gynecology and Obstetrics (FIGO) stage ≥IIIB disease, aged between 18 and 70 years, with a laparoscopic Predictive Index value (PIV) ≤8 and residual disease ≤2.5 mm were included. Results: 70 patients were included. With the except of age (p = 0.012), the populations were balanced for the main characteristics. At a median follow-up of 48 months, no differences in Progression Free Survival (PFS) (p = 0.968) and Overall Survival (OS) (p = 0.789) were recorded. Survival analysis according to HIPEC administration and BRCA mutational status showed an improved PFS (p = 0.011) and OS (p = 0.003) in BRCA mutated compared to wild-type patients when HIPEC was not administered, whilst they were superimposable in case of HIPEC administration (p = 0.857 vs p = 0.372; respectively). No differences in terms of neither intra-operative (p = 1.0) nor early post-operative complications (p = 0.920) were detected. Conclusions: Our results show that HIPEC in AOC may be a promising treatment in BRCA wild-type patients, as it seems to balance their decreased chemosensitivity compared to mutation carriers.