Four distinct immune microenvironment subtypes in gastric adenocarcinoma with special reference to microsatellite instability

Abstract

INTRODUCTION: ) or microsatellite instability-high (MSI-H) gastric cancer (GC) subtypes. We aimed to determine the tumour immune microenvironment (TME) classification of GC to better understand tumour-immune interactions and help patient selection for future immunotherapy with special reference to MSI-H. METHODS: /MSS) were performed and analysed. In 66 MSI-H GC, mutation counts were compared with PD-L1 expression and survival of the patients. RESULTS: and the numbers of frameshift mutation correlated significantly with PD-L1 expression (P<0.05). DISCUSSION: GC can be classified into four TME types based on PD-L1 and TIL, and numbers of frameshift mutation correlate well with PD-L1 expression in MSI-H GC.