A 65-year-old man presented with liver dysfunction. Abdominal contrast-enhanced computed tomography (CT) revealed findings suggestive of advanced gastric cancer and a lower bile-duct tumor with hilar lymph node and abdominal para-aortic lymph node metastasis. Esophagogastroduodenoscopy (EGD) showed ulcer-like lesions extending from the cardia to the lower gastric body. Endoscopic retrograde cholangiopancreatography (ERCP) showed severe stenosis of the lower bile duct. Histopathological examination of biopsy specimens obtained from the stomach and duodenal papilla showed moderately to poorly differentiated adenocarcinoma. The findings were suggestive of a bile duct metastasis from the gastric cancer, or a double cancer of the stomach and lower bile duct cancer. Because of the presence of distant metastases, the patient was administered chemotherapy directed against the gastric cancer. At the time of writing, the gastric cancer has shrunk slightly, and the lymph node metastasis has disappeared. On the other hand, the stenotic portion of the lower bile duct has expanded, and the tumor at the duodenal papilla has grown. On the basis of these findings, we diagnosed double cancer. We describe our experience with an extremely rare case of concurrent gastric cancer and lower bile duct cancer and discuss the case with a review of the literature.
