Key points are not available for this paper at this time.
AbstractPurpose: Homologous-recombination deficiency (HRD) is closely related to PARPi benefit in ovarian cancer (OC). The capacity of BRCA1 promoter methylation to predict prognosis and HRD status remains unclear. We aimed to correlate BRCA1 promoter methylation levels in patients with high-grade OC to HRD status and clinical behavior to assess its clinical relevance. Design: This is a retrospective monocentric analysis of patients centrally tested for genomic-instability score (GIS) by MyChoice CDx (Myriad Genetics). The detection of BRCA1 promoter methylation and quantification of methylation levels were performed by quantitative ddPCR methodology. High BRCA1 methylation was defined as ≥70% and deemed to be associated with homozygous silencing. Results: Of 100 patients, 11% harbored a deleterious BRCA1/2 mutation. GIS was considered positive (score≥42) for 52 patients and negative for 48 patients. Using a 70% cutoff, 19% (15/79) of BRCA-wild-type OC had high BRCA1 methylation levels. All of the highly methylated tumors were classified HRD achieving a positive predictive value of 100%. We detected 14% (11/79) low methylated tumors (1-69%) and all of them were also classified as HRD. Mean GIS was 61.5 for BRCAmut, 66.4 for high-BRCAmeth, 58.9 for low-BRCAmeth and 33.3 for BRCAwt unmethylated (P
Blanc‐Durand et al. (Mon,) studied this question.