Clinical outcome of breast cancer in carriers of BRCA1 and BRCA2 mutations according to molecular subtypes
Solène De Talhouet, Julien Péron, Aurélie Vuilleumier, Alex Friedlaender, Valeria Viassolo, Aurélie Ayme, Alexandre Bodmer, Isabelle Treilleux, Noémie Lang, Jean Christophe Tille, Pierre O. Chappuis, Adrien Buisson, Sophie Giraud, Christine Lasset, Valérie Bonadona, Olivier Trédan, Sana Intidhar Labidi‐Galy
Abstract
BRCA1/BRCA2 genes play a central role in DNA repair and their mutations increase sensitivity to DNA-damaging agents. There are conflicting data regarding the prognostic value of BRCA germline mutations in breast cancer (BC) patients. We collected clinical, pathological and genetic data of a cohort 925 BC patients preselected for genetic screening and treated with neoadjuvant or adjuvant chemotherapy, of whom 266 were BRCA carriers. Overall, 171 women carried a BRCA1 mutation, 95 carried a BRCA2 mutation, and 659 were non-carriers. In the entire cohort, there was a prolonged disease-free survival (DFS) for BRCA carriers (hazard ratio (HR) = 0.63; 95% confidence interval (CI), 0.44-0.90 for BRCA1; HR = 0.72; 95%CI, 0.47-1.1 for BRCA2; p = 0.020) and a trend toward prolonged disease-specific survival (DSS; HR = 0.65; 95%CI, 0.40-1.1 for BRCA1; HR = 0.78; 95%CI, 0.44-1.38 for BRCA2; p = 0.19) though not statistically significant. In the TNBC group, BRCA carriers had prolonged DFS (adjusted HR = 0.50; 95%CI, 0.28-0.89 for BRCA1; adjusted HR = 0.37; 95%CI, 0.11-1.25, for BRCA2; p = 0.034) and DSS (adjusted HR = 0.42; 95%CI, 0.21-0.82 for BRCA1; adjusted HR = 0.45; 95%CI, 0.11-1.9 for BRCA2; p = 0.023). In the non-TNBC group, the BRCA1 or BRCA2 mutations did not have any impact on survival. These results suggest that BRCA1/BRCA2 germline mutations are associated with prolonged survival only if women were diagnosed with TNBC.