Oncological outcomes of intraperitoneal chemotherapy in advanced ovarian cancer: BRCA mutation role

Introduction: The knowledge of BRCA status offers a chance to evaluate the role of the intraperitoneal route in patients selected by biomolecular profiles after primary cytoreduction surgery in advanced ovarian cancer. Materials and methods: We performed a retrospective, multicenter study to assess oncological outcomes depending on adjuvant treatment (intraperitoneal [IP] vs intravenous [IV]) and BRCA status (BRCA1/2 mutated vs. BRCA wild type [WT]). The primary endpoint was to determine progression -free survival. The secondary objectives were overall survival and toxicity. Results: A total of 288 women from eight centers were included: 177 in the IP arm and 111 in the IV arm, grouped into four arms according to BRCA1/2 status. Significantly better PFS was observed in BRCA1/2-mutated patients with IP chemotherapy (HR: 0.35; 95% CI, 0.16 -0.75, p = 0.007), which was not present in BRCA1/2-mutated patients with IV chemotherapy (HR: 0.65; 95% CI, 0.37 -1.12, p = 0.14). Significantly better OS was also observed in IP chemotherapy (HR: 0.17; 95% CI, 0.06 -043, p < 0.0001), but was not present in IV chemotherapy in relation with BRCA mutation (HR: 0.52; 95% CI, 0.22 -1.27, p = 0.15). For BRCA WT patients, worse survival was observed regardless of the adjuvant route used. The IP route was more toxic compared to the IV route, but toxicity was equivalent at the long-term follow-up. Conclusion: This retrospective study suggests that BRCA status can help to offer an individualized, systematic treatment after optimal primary surgery for advanced ovarian cancer, but is limited by the small sample size. Prospective trials are essential to confirm these results.