Clinical and genomic features of high tumor mutation burden in patients with non-small cell lung cancer.

e21023 Background: TMB is associated with mono-immunotherapy efficacy for patients with advanced or metastatic non-small-cell lung cancer (NSCLC). For early-stage NSCLC or EGFR mutated non-resectable NSCLC, TMB-H predicted better prognosis or poor response to TKIs. This research might develop potential predictive parameters for distinguishing NSCLC with high or low TMB. Methods: Samples of surgically resected, cancer tissues were collected from 499 patients with NSCLC: 29 (5.8%) lung squamous cell carcinoma (LUSC) and 468 (94.2%) lung adenocarcinoma (LUAD). The mutations and TMB were confirmed by target region capture sequencing (Oseq™-508). Results: According to the median value (3.08), TMB is divided into high (N = 244) and low (N = 255). Interactions between TMB and sex, age, location, histology, pathological subtype, lymph node, parabronchial lymph node, LVI, neuro-invasive, stage and mutation status were evaluated. The distribution of TMB-H was significantly (p < 0.001) correlated with sex, age, histology, pathological subtype, stage (TN stage) and partial mutations. Among all mutations, 6 genes (TP53 / FAT3 / KMT2D / TSHZ3 / NAV3 / EPHA3) were confirmed to be significantly related to TMB-H in NSCLC. We also found that TMB-H was significantly affected by mutation status of KRAS gene (P. G12X, p < 0.001) and missense mutations in FAT3 (p < 0.001). The Kruskal–Wallis H test results showed that the mutation types of FAT3, KRAS, TP53 and PIK3CA were closely related to TMB-H. Lasso linear regression analysis was applied and resulted the better predictors of TMB status including TSHZ3, KMT2D, TP53, gender and T stage. Conclusions: Instead of comprehensive genomic profiling to evaluate TMB, clinical characteristics and special mutation types may help to effectively screen and predicate patients with TMB-H status. [Table: see text]