In almost all cases, colloid carcinoma develops from pre-existing intraductal papillary mucinous neoplasms, especially those forming intestinal-type papillae, and is characterized by MUC2 expression, which is rarely found in pancreatic ductal carcinoma [6, 7]. The gene discussed is MUC2; the disease is pancreatic intraductal papillary-mucinous neoplasm.