[Transverse ectopia of the right testicle and tumor of the left testicle with immature uterus and fallopian tubes: report of a case].

A case of transverse ectopia of the right testicle and the left testicular tumor with the immature uterus and the fallopian tubes is reported. The patient, a 27-year-old married man, was admitted to our hospital with the suspicion of left testicular tumor and right undescended testicle. In his left scrotum, a double hen-egg-sized tumor was palpable and the right scrotum was empty. Exploration of the left inguinal canal disclosed double testicles with hernia uteri inguinalis. The right testicle showed transverse ectopia, and the histological finding of the left testicle was choriocarcinoma. In our review of the Japanese literature, we discovered 67 reported cases of transverse testicular ectopia. 33 (49.3%) out of 67 cases had a uterus and 9 cases (13.4%) had testicular tumor.