CD8A and mismatch repair cancer syndrome 1: The significant association between MMR deficiency and high number of intratumoral CD8-positive lymphocytes found for pancreatic cancer in this study is consistent with earlier data from colorectal, endometrial and stomach cancer.19–21,61 Elevated lymphocyte counts may represent evidence for immunogenic events having occurred in a cancer, a feature that is believed to be essential for successful therapy with immune checkpoint inhibitors.