KRT7 and intestinal type adenocarcinoma: In a previous study, the CK7+/CK20-/MUC2- pattern in the histological intestinal-type carcinoma and the CK7-/CK20+/MUC2+ pattern in the histological pancreatobiliary-type carcinoma indicated that these different types of ACs had developed from 2 different types of mucosa in the ampulla of Vater[1].