Germline mutations in Brazilian pancreatic carcinoma patients.

Abstract

e16749 Background: Pancreatic cancer has the prospect of becoming the second leading cause of cancer death by 2030. The NCCN Guidelines recommend genetic testing for all patients with pancreatic cancer, however, the spectrum of germline mutations has not been extensively evaluated because recent studies with genetic testing have explored only a limited number of genes and have focused predominantly on Caucasian populations. Therefore, our objective is to evaluate the frequency and spectrum of germline mutations in unselected patients with pancreatic cancer in a multiethnic population. Methods: Patients from Instituto do Câncer do Estado de São Paulo (Brazil) with histopathological diagnosis of non-endocrine pancreatic carcinoma were included, regardless of the family history of cancer. These patients answered a life habits and family history of cancer questionnaire and supplied blood for the Next Generation Sequencing (MiSeq platform) with the TruSight Hereditary Cancer panel (Illumina), which includes 115 cancer predisposing genes. Variant analysis was performed with the VarStation, a Brazilian tool that offers post-sequencing computational support and aid for clinical interpretation. Results: To the present moment, 77 patients were evaluated. The mean age of the patients was 62 years (27-83), among whom, 13% with young age (≤50 years) and 47 women (61%). Thirty-eight patients (49%) reported cases of cancer in first-degree relatives. Regarding risk factors, 41 patients (53%) reported smoking, 19 (25%) alcohol ingestion and 20 (26%) had obesity. Seven out of 77 patients presented pathogenic variants in ATM (n = 2) , CHEK2, FANCM (n = 2) or PALB2 (n = 2) genes. Two of these patients ( CHEK2 and FANCM) had early onset pancreatic cancer (≤45 years), both denied smoking habit and family history of cancer in 1st degree relatives. Two patients, who were ATM mutation carriers, reported 1st or 2nd degree relatives with cancer and are alive after 4 and 8 years of diagnosis. Conclusions: In this unselected group of pancreatic cancer patients, 15% were young, almost half reported first-degree relatives with cancer and 9% were carriers of pathogenic variants in genes related with the homologous recombination DNA repair.