Patil PA, et al. - The relationship between the immune microenvironment and clinicopathologic parameters in gastric adenocarcinomas was determined. The expression of programmed death ligand 1 (PD-L1) was noted in a large proportion of gastric carcinomas, suggesting that therapy targeting this pathway could be of relevance. A connection was demonstrated between PD-L1 expression and mismatch repair protein (MMR)-deficiency with increased tumor-infiltrating lymphocytes (TILs) and larger tumor size, which stressed their role in tumor biology. Higher stromal indoleamine 2,3-dioxygenase (IDO) expression was related to better prognosis. High expression of immune modulators (tryptophanyl-tRNA synthetase and guanylate-binding protein 5) in gastric adenocarcinomas highlighted the significant role in tumor pathobiology.