MA14.01 Clinical and Genomic Features of Chinese Lung Cancer Patients with Germline Mutations

Recent studies on next generation sequencing (NGS) data from cancer patients have demonstrated that germline mutations in genetic predisposition genes were more common than previous known in many cancer types including lung cancer. However, most previous studies have focused on western patient population and the germline mutation landscape in Asian lung cancer patients and the clinical and genomic features in these patients are largely unknown. NGS data from a targeted panel of 1,021 known cancer genes from paired cancer and germline DNA of 1,797 Chinese lung cancer patients was analyzed to identify pathogenic or likely pathogenic (P/LP) germline variants in predisposition genes based on American College of Medical Genetics and Genomics (ACMG) 2015 guideline. Totally, 5.95% of lung patients were found to harbor germline variants in 35 cancer predisposition genes. The prevalence of germline mutations was higher in patients under 40 compared to older counterparts (10.1% vs 5.74%, p=0.103, Chi-Square test) although it did not reach statistical significance. However, germline BRCA1/2 mutations were associated with earlier age of onset (median 52.5 vs 60 years-old, p=0.0080 by Mann-Whitney test). Furthermore, patients with P/LP germline mutations had significantly more somatic mutations in KRAS (p=0.012, fisher’s exact test) and c-MET (p=0.018, fisher’s exact test) oncogenes, but less in tumor suppressor gene TP53 (p=0.019, fisher’s exact test). Compared to western lung cancer patients enrolled in TCGA, P/LP germline mutations in BRCA2, FANCA, ATM, MUTYH, BLM, TP53, BRCA1, CHEK2, PMS2, NBN and FANCC were identified in both current Chinese cohort and TCGA cohort with BRCA2 germline mutations significantly more common in Chinese cohort than TCGA cohort (p=0.015, Fisher’s exact test). In addition, RAD51D, FANCD2, BRIP1, MSH6, PMS1, PALB2, RAD51C, SDHA, TSC2, BAP1, CDH1, FLCN, NF1 and RUNX1) were exclusively identified in Chinese patients, while RET, ERCC3, FANCG and VHL were only detected in TCGA cohort. These results implied that there might be both common and unique cancer predisposition germline mutations for lung cancer between Asian and Western patient populations.