Family history and germline alterations in metastatic prostate cancer patients.

Abstract

231 Background: Recent literature has highlighted the importance of germline genetic testing in metastatic prostate cancer (PCa)patients (pts). This retrospective study evaluated family history (FH), evaluate treatment outcomes in metastatic patients with pathogenic germline mutations, and compared family history in Caucasian (CA) and Africans Americans (AA). Methods: At Tulane Cancer Center, 428 metastatic PCa pts had germline testing in at least 79 genes. Comprehensive family histories were obtained in all. Analysis of prevalent FH, including breast, ovarian, prostate, and pancreatic cancers was assessed for all metastatic pts. Statistical analyses including chi square were performed. Results: 64 (64/428; 14.9%) pts had at least one or more pathogenic mutations, while 166 (166/428; 38.7%) had were normal. The remaining 199 (199/428; 46.4%) of pts had a variant of uncertain significance (VUS). Pts with a DNA repair pathogenic mutation were more likely to have >2 family members affected by cancer, regardless of cancer type or degree of relationship (p=0.0047); 6 pts without any family history of cancer had a pathogenic mutation. In CA, the presence of either a breast or PCa family history was associated with pathogenic germline findings (p=.022/.0367) However, in AAs neither breast nor prostate cancer predicted pathogenic germline alterations. Conclusions: The correlation between family history of breast and PCa cancer in CA pts with pathogenic mutations is notable as is the finding of >2 family members with cancer predicting germline pathogenic alterations. With AA pathogenic pts, there was no correlation of family history of breast and PCa, which highlights the need to learn more about the genetic factors which influence AA prostate cancer risk.[Table: see text]