Whole BRCA1/2 exome screening in breast cancer tissue: Preliminary study on 45 patients negative in preventive screening analysis in Poland which cover the most common mutations in BRCA1/2 tested in blood.

e13615Background: The standard genetic preventive test in Poland covered 3-5 of the most common mutations, including BRCA1: c.5266dupC, c.181T > G, c.4034delA and BRCA2: c.6174delT, c.5972C > T. Recent NGS analysis showed that this screening test misses up to 35% of germline BRCA1/2 mutations. Furthermore, identification of BRCA1/2 somatic mutations is important prior to treatment with PARP inhibitors. Our aim is to evaluate percentage of mutation using NGS in patients, who had been defined as BRCA1/2 negative with the standard panel, but developed breast cancer. Secondly – we determine the quality metrics of archival DNA which are suitable for NGS Methods: A total of 45 breast cancer patients diagnosed between 2009-2017 (F.Lukaszczyk Oncology Center,Poland) BRCA1/2 negative for 5 common mutations observed in the Polish population were referred after informed consent. Isolated DNA (Qiagen) was quantified using the qPCR-based Fragmentation Quantification Assay–FQA (EntroGen) and calculated using two F-rati...