Testicular Carcinoid Tumor in a Patient With Contralateral Classic Seminoma.

Testicular neuroendocrine tumors, commonly called carcinoid, are extremely rare and account for less than 1% of all testicular neoplasms. The most common type is primary carcinoid followed by testicular metastasis from another primary and rarely carcinoid within a testicular teratoma. To date, less than 25 cases of carcinoid associated teratomas have been reported in the literature. Herein, we present a unique case of testicular carcinoid tumor arising in association with mature teratoma in a patient with contralateral classic seminoma.