Influence Of Brca Pathogenic Variants In The Benefit Of Secondary Cytoreductive Surgery.

6076 Background: Germline BRCA pathogenic variants are present in 15% to 25% of ovarian carcinoma patients. These tumors are more sensitive to platinum and PARP inhibitor therapy and have a better prognosis. Two retrospective studies with limited number of patients have shown conflicting results regarding the benefit of secondary cytoreductive surgery (SCS) in patients with BRCA mutations. Our aim was to evaluate the impact of SCS in recurrent ovarian cancer according to BRCA status. Methods: All patients with ovarian carcinoma with recurrent disease and who were tested for BRCA pathogenic variants treated at a tertiary Cancer Center in Brazil were included. Patients characteristics were compared between patients treated with SCS and not treated with SCS. Cox regression analysis was used to evaluate the impact of SCS on progression free survival (PFS) and the influence of BRCA pathogenic variants on the effect of SCS. Results: One hundred and forty patients were included, 49.6% were treated with SCS and chemotherapy and 50.4% treated with chemotherapy only. Patients treated with SCS were younger, presented better performance status, lower CA 125 and longer platinum free interval. After adjusting for relevant covariables SCS was associated with longer PFS (HR 0.53, 95%CI 0.29-0.97, p = 0.039). Germline BRCA pathogenic variants were found in 37 patients (26.4%). No patient was treated with PARP inhibitors. Among non-carriers of pathogenic variants in BRCA, SCS lead to a longer PFS (HR 0.48, 95%CI 0.28-0.81, p = 0.006) but among carriers there was no benefit of SCS (HR 0.84, 95%CI 0.30-2.34, p = 0.735). Test for interaction was not statistically significant (p = 0.359). Conclusions: Our study is the second to demonstrate no benefit of SCS among patients with BRCA pathogenic variants and not treated with PARP inhibitor. The only other study to show a benefit of SCS in this group of patients included a limited number of patients and all of them were treated with PARP inhibitors. BRCA germline status might influence the efficacy of SCS, and should be evaluated as a potential biomarker to be assessed together with clinical factors to better select patients for SCS.