Mutational analysis of BRCA1/2 in a group of 134 consecutive ovarian cancer patients. Novel and recurrent BRCA1/2 alterations detected by next generation sequencing.

ABSTRACT

The importance of proper mutational analysis of BRCA1/2 in individuals at risk for hereditary breast and ovarian cancer syndrome is widely accepted. Standard genetic screening includes targeted analysis of recurrent, population-specific mutations. The purpose of the study was to establish the frequency of germline BRCA1/2 mutations in a group of 134 unrelated patients with primary ovarian cancer. Next generation sequencing analysis revealed a presence of 20 (14.9%) mutations, where 65% (n = 13) were recurrent BRCA1 alterations included in the standard diagnostic panel in northern Poland. However, the remaining seven BRCA1/2 mutations (35%) would be missed by the standard approach and were detected in unique patients. A substantial proportion (n = 5/12; 41%) of mutation-positive individuals with complete family history reported no incidence of breast or ovarian cancer in their relatives. This observation, together with the raising perspectives for personalized therapy targeting BRCA1/2 signaling pathways indicates the necessity of comprehensive genetic screening in all ovarian cancer patients. However, due to the limited sensitivity of the standard genetic screening presented in this study (65%) an application of next generation sequencing in molecular diagnostics of BRCA1/2 genes should be considered.