CTLA4 and pancreatic neoplasm: Unfortunately, both anti-PD-1 and anti-CTLA4 antibody therapy are not effective in pancreatic cancer,11,12 except in rare patients with mismatch repair deficient tumours,13 which account for less than 2% of pancreatic tumours.13,14 On the other hand, immune checkpoint antibody therapy has not been studied yet in ampullary cancer.