Primary carcinoid tumor of the testis: case report, ultrastructure and review of the literature.

A case of primary pure carcinoid tumor of the testis which occurred in a 71-year-old male is reported. The patient was treated by radical orchiectomy and remains well and symptom free 10 months after operation. Histologically as well as ultrastructurally the tumor showed typical appearances of carcinoid tumor of midgut derivation. 23 cases of carcinoid tumors of the testis were discovered in the literature. Of these 17 were primary testicular carcinoids, and 6 were metastatic to the testis. Of the 17 cases of primary carcinoid tumors, 14 were pure carcinoids and only 3 were associated with teratoma. None of the primary testicular carcinoids were associated with metastases and the prognosis after orchiectomy was excellent, thus indicating that no further therapy is necessary. The prognosis of patients with carcinoid metastatic to the testis is poor. In view of this it is very important to determine whether the tumor is primary or metastatic.