Intra-abdominal testis with mature teratoma.

Tumors in an undescended testis are rare in children. We report a mature teratoma arising in the intra-abdominal testis (IAT) of a 1-year-old boy. Preoperative laparoscopy revealed a right IAT near the inguinal ring. As the right testis exposed through the inguinal incision seemed to be a neoplastic mass, an orchidectomy was performed. Histologic examination disclosed a mature teratoma. This is a review of seven cases (including the present one) of a prepubertal tumor originating in an IAT. We speculate that the undescended testes did not cause the neoplasia, but were induced by it.