BRCA1/2 mutations and expression: Response to platinum chemotherapy in patients with advanced stage epithelial ovarian cancer

Objective. Our objective was to determine the rate of BRCA1/2 deficiency in platinum-sensitive and platinum-resistant tumors from a cohort of unselect patients with advanced epithelial ovarian cancer (EOH). Methods. BRC41/2 mutation analysis was performed in 29 patients with platinum-sensitive EOC and 24 patients with platinum-resistant disease. Germline DNA was analyzed in mutation carriers when normal tissue was available. BRCA expression was ascertained by quantitative rt-PCR. Associations between BRCA mutation status and expression levels and parameters of platinum response were analyzed. Results. Fifteen of 53 (28.3%) EOC tumors had BRCA1/2 mutations. Twelve mutations were in BRCA1, while 3 involved BRCA2. Of the 12 mutation-carriers with normal tissue available for DNA analyses, 33.3% of the mutations were found to be somatic. Three mutations were novel. The majority of BRCA mutations (73%) were identified in patients with platinum-sensitive disease. In total, 38% of platinum-sensitive tumors were found to have a BRCA mutation, compared to 17% of the platinum-resistant patients. A statistical trend toward platinum-sensitive disease was seen in BRCA mutation carriers (p = 0.079). Nineteen (36%) study patients had some form of BRCA deficiency, and these patients were less likely to have platinum-resistant tumors (OR = 0.29; p value = 0.048). Conclusions. BRCA mutations occurred more frequently in platinum-sensitive EOC than platinum-resistant disease. The high overall frequency of BRCA deficiency in EOC underscores the importance of tumor profiling as therapies targeting the DNA repair pathway are being investigated. (C) 2012 Elsevier Inc. All rights reserved.