Association of homologous recombination repair mutation defined with a 15-gene panel with the prognosis of epithelial ovarian cancer: A Chinese multicenter retrospective study.

Abstract

e17556 Background: There was no consensus regarding the optimal homologous recombination repair (HRR) gene panel to predict prognosis of epithelial ovarian cancer (EOC). Methods: The genetic testing results in a 15-gene panel from 308 EOC patients diagnosed between 2014 and 2022 from six centres were collected. The association of clinicopathologic characteristics, the use of poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitors and progression-free survival (PFS) with 15-gene panel mutation status was assessed. Results: 43.2% (133/308) of patients were determined to carry 144 deleterious HRR mutations (HRRm), among which 68.1% (98/144) were germline mutations and 32.8% (101/308) were BRCA1/2 gene lethal mutations. Patients who received PARP inhibitors (PARPis) were 29.1% (37/127) and 50.5% (46/91) in the HRR wild-type (HRRwt) group and HRRm group at IIIC-IV stages, respectively. A prognostic difference was observed only between the BRCA mutation group and the HRRwt group, not between the non-BRCA HRRm group and the HRRwt group. In univariate analysis, significant predictors of relapse included nonresidual status (HR, 0.62; 95% CI, 0.39-0.98; P = 0.0287), 15-gene panel mutation (HR, 0.42; 95% CI, 0.28-0.64; P = 0.0001), platinum sensitivity (HR, 0.07; 95% CI, 0.02-0.22; P < 0.001) and maintenance therapy (PARPi) (HR, 0.48; 95% CI, 0.31-0.74; P = 0.0028) (Figure 5). In multivariate Cox analysis, nonresidual (HR, 0.63; 95% CI, 0.40-0.99; P = 0.046), 15-gene panel mutation (HR, 0.49; 95% CI, 0.28-0.88; P = 0.016) and platinum sensitivity (HR, 0.02; 95% CI, 0.01-0.05; P < 0.001) remained independent prognostic factors. Conclusions: This study provides evidence that HRRm with a 15-gene panel can predict the prognosis of EOC, among which only BRCA1/2 mutations contribute to prognosis prediction. [Table: see text]