HLA-C and neoplasm: A major issue in the host defense with consequences for immunotherapies is the tumor-immune-evasion,53 which may be a consequence of the downregulation of recognition structures on the cancer cells, such as MHC molecules.38 In this context, PDAC 39 is well known to downregulate the expression of MHC class I molecules as well as proteins of the MHC-I processing pathway, probably to escape a cytotoxic response mediated by CD8+ T-cells.