Carcinoid tumor as a part of mature teratoma of the testis.

A rare case of primary carcinoid tumor in otherwise mature teratoma of the testis which occurred in a 70-year-old male is reported. The patient was treated by unilateral orchiectomy. The pathological specimen showed morphological characteristics of carcinoid in the teratomatous tumor. The immunohistochemical studies revealed positivity for chromogranin and neuron-specific enolase. Grimelius staining showed argyrophil granules in cells. Symptoms of a carcinoid syndrome were not noted. The patient remains disease free after surgery.