Germ cell tumor with duodenal involvement: a rare case of gastrointestinal bleeding.

A 19-year-old male presented to the emergency department with a 7-day history of melena, anorexia and asthenia. Blood tests revealed a hemoglobin of 5.8 g/dL. Upper endoscopy showed a large ulcerated and stenosing lesion in the duodenum. The histologic examination of the biopsy specimen showed a neoplasia with epithelioid cells, accentuated atypia and pleomorphism, expressing MNF 116 cytokeratin, CD30, glypican 3 and alpha-fetoprotein on immunohistochemistry, suggesting of a germ cell tumor metastasis.