Fifty-one of 484 (10.54%) patients had at least one somatic mutation in HR-gene, ATM (16/484, 3.31%), ATRX (14/484, 2.89%), and ATR (13/484, 2.69%) were among the top mutated HR-gene in...MSK-GC cohort, including a total of 49 patients who had stomach adenocarcinoma (STAD) or gastroesophageal junction adenocarcinoma (GEJ) and treated with ICIs, HR-mut GC (n = 12) had a significantly better OS than HR-wt GC (n = 37) (log-rank test, P = 0.034).