Ectopic and undescended testes: 2 variants of a single congenital anomaly?

Purpose: We compared pathological findings in ectopic and undescended testis to determine whether the pathological evidence supports the hypothesis that the 2 conditions are variants of the same congenital anomaly. Materials and Methods: We identified 24 boys with ectopic testis not in the superfical inguinal pouch of Denis Browne. Seven boys were excluded from study due to unavailable clinical records for 3, contralateral undescended testis in 2 and inadequate: biopsy specimens in 2. Pathological findings of ectopic testis in the remaining 17 patients were compared with those of age matched patients with unilateral undescended testis. Total germ cell count, testicular volume, patency of the processus vaginalis and epididymal abnormalities were compared. Data were analyzed using the Wilcoxon matched pairs signed rank and Fisher's exact tests. Results: No difference was noted in total germ cell count (p = 0.33), testicular volume (p = 0.1475), processus vaginalis patency (p = 0.0854) or epididymal abnormalities (p = 1.00) in the 2 groups. Of the 24 boys (8%) with ectopic testis 2 also had a contralateral undescended testis. Conclusions: Similar pathological findings in ectopic and undescended testes as well as the association of ectopic testis with a contralateral undescended testis suggest that ectopic and undescended testes are variants of the same congenital anomaly. Thus, boys with ectopic testis may have an increased incidence of subfertility and testicular malignancy. This spectrum of abnormal testicular position, and its range of pathological conditions and complications may appropriately be called the undescended testis sequence.