Genomic and clinical characteristics of MET alterations in solid tumors among the 10,475 Chinese patients.

Abstract

3115 Background: Somatic alterations of the MET oncogene are emerging as an attractive target in human cancers, thus, understanding the molecular epidemiology of MET alterations is essential. While the occurrence of MET exon 14 skipping mutations (MET ex14) in US lung cancer patients is well defined, it is not widely published for Chinese patients. In addition, reports on the occurrence of METex14 outside lung cancer and other clinically relevant MET alterations across all cancers are limited. Methods: The MET ex14 alterations and amplification data of 10475 Chinese cancer patients from 16 types of cancer were obtained in Acronmed database, including non-small cell lung cancer (NSCLC, n = 5719), Hepatocellular carcinoma (HCC, n = 511), colorectal cancer (CRC, n = 1779), renal cell carcinoma (RCC, n = 1169), Gastric carcinoma (GC, n = 679), etc. Genomic profiling of DNA was performed through a next-generation sequencing. Results: Of all pan-cancer patients, 141 cases (1.3%) with MET alterations were identified, including MET Amp (0.9%) and MET ex14 (0.7%). Compared to Western population (̃3%), the frequency of MET alterations is much lower in Chinese cancer patients (1.3%). MET Amp were most commonly found in HCC (1.7%), GC (1.3%), NSCLC (0.7%), RCC (0.7%), CRC (0.2%). MET ex14 occurred most in NSCLC (0.5%), HCC (0.3%), CRC (0.2%). HCC were significantly to have MET Amp than NSCLC (P = 0.01), while MET ex14 mutations were more likely to be observed in NSCLC (p = 0.02). We further analyzed the MET mutation characteristics of NSCLC. The most frequently co-mutated genes in MET ex14 cohort were TP53 (48%,15/31), KMT2B (23%,7/31) and EGFR (16%, 5/31). Except for TP53 (65%,22/34) and EGFR (56%,19/34) mutations. Interestingly,other gene mutations were rare in the patients with MET Amp. In addition, MET ex14 patients showed significant lower EGFR mutation comparing to the MET amp patients (P = 0.002). Conclusions: Our study demonstrated a landscape of MET alterations among the Chinese population. MET mutations occurs in a variety of solid tumors, indicating that these patients may benefit from MET inhibitors.