In univariate analysis, PD-L1 expression was significantly associated with GC-MLI (P<.001), lower age (P=.019), EBV infection (P<.001), lower HER2 expression (P=.011), and diffuse/mixed type of histology (P=.022).
HER2 expression, PIK3CA mutations and EBV infection in gastric cancer were characterized. pAkt expression significantly correlates with HER2 expression and with a poor prognosis.