[A case of AFP-producing gastric cancer accompanied with testicular tumor].

A case of an AFP-producing gastric cancer accompanied with non-epithelial tumor is reported. A 63-year-old man, complaining of an epigastric hunger pain, was admitted to our hospital. Testing revealed that he had an extremely high level serum AFP (12,400 ng/ml) with no abnormality of liver function. A barium ingestion and a subsequent endoscopic examination determined the existence of a Borrmann III type advanced gastric cancer on the lesser curvature, extending from middle corpus to the antrum. Diagnostic imaging did not reveal any metastatic lesion in liver. After a total gastrectomy, the patient's serum AFP level rapidly decreased, followed by a recurrence he developed of a carcinomatous pleuritis and death. On autopsy, an enlargement of the right testis was noticed for the first time. Histologically, it was found to be a malignant, non-epithelial tumor, which proved negative for anti-AFP staining by the ABC method and positive for anti *L-26. On the other hand, the gastric cancer was a poorly differentiated adenocarcinoma with a hepatoid differentiation which was positive for anti-AFP staining and negative for anti-L-26 so it thus was diagnosed as an AFP-producing gastric cancer.