Gastric metastasis from pancreatic ductal adenocarcinoma: a case report.

Pancreatic ductal adenocarcinoma (PDAC) rarely metastasizes to the gastrointestinal tract. Herein, we report a case of gastric metastasis from PDAC. An 83-year-old woman presented with a mass in the pancreatic tail. CT revealed a 5 cm neoplastic lesion in the pancreatic tail invading the splenic vessels and parenchyma, with lymph node metastasis. Collateral veins developed in the posterior stomach wall nine courses of chemotherapy were administered. After chemotherapy, esophagogastroduodenoscopy revealed an irregularly elevated lesion in the gastric body, which was identified as an adenocarcinoma. These lesions were considered resectable, and surgery, including distal pancreatectomy, splenectomy, lymph node dissection, and partial gastrectomy, was performed. Pathological examination revealed that the stomach wall had an extension of well-differentiated adenocarcinoma, mainly in the submucosa. The immunohistochemical staining pattern was similar to PDAC; therefore, gastric metastasis was diagnosed. The final pathological diagnosis was pT3N1M1 (stomach, LYM), pStage IV.