Gastrointestinal hemorrhage as the first manifestation of metastatic extragonadal choriocarcinoma.

Although germ cell tumors are the most common malignancy in young men, extragonadal germ cell tumors are rare. Gastric metastasis presenting initially as upper gastrointestinal hemorrhage is also exceedingly rare. A 27-year-old man presented at our hospital with tarry stool. Gastric fiberscopy images revealed a bleeding gastric polypoid lesion in the anterior wall of the gastric body, from which a biopsy specimen was obtained. Histopathological analysis of the biopsy showed syncytiotrophoblast-like cells with multiple, large nuclei, consistent with choriocarcinoma. Based on these results, our diagnosis was extragonadal retroperitoneal germ cell tumor with gastric metastasis.