BRCA1 and ovarian cancer: One (25.0%) in four primary platinum‐resistant versus zero (0%) in 56 primary platinum‐sensitive, BRCA‐mutated ovarian cancers, as well as 12 (46.2%) platinum‐resistant versus one (5.3%) platinum‐sensitive recurrent BRCA‐mutated ovarian cancers, exhibited secondary mutations in BRCA1/2 that restored the ORF of the gene.