SMAD4 and pancreatic ductal adenocarcinoma: Both pancreatoblastoma and acinar cell carcinomas consistently exhibit acinar differentiation [1], as well as alterations in the genes for Wnt/β-catenin signaling, including inactivating mutations in APC and activating mutations in CTNNB1; however, they lack alterations in the genes commonly mutated in pancreatic duct adenocarcinoma, including KRAS, TP53, P16/CDKN2A, and SMAD4 [8].