Sentinel Nubbin: A Potential Pitfall in the Management of Undescended Testis Secondary to Epididymo-Testicular Nonunion

Abstract

Introduction Epididymal anomalies are common in boys with undescended testis. Epididymo-testicular non-union with a nubbin in the scrotum is a rare anomaly and may be confusing during management of cryptorchidism. The non-fused epididymis and vas deferens which are descended to the scrotum, may be regarded as nubbin tissue secondary to testicular atrophy and proximal testis may be overlooked. Objective To evaluate a relatively rare anomaly of epididymotesticular non-union in which vas deferens and epididymis are descended to the scrotum resembling a nubbin tissue, while a separate testis remains in a proximal peritoneal fold (hernia or processus vaginalis)which could potentially be missed during the management of patients with undescended testis. Study design The charts of the fourteen patients with epididymotesticular non-union and a scrotal nubbin are retrospectively evaluated. Results Median age of the patiens was 1.5 years (0.5-12), 11 were left and 3 were right. No connection could be demonstrated between the testis and vasoepididymal unit in any of the patients. Orchidopexy was performed in 13 patients while orchidectomy inl patient. The scrotal nubbin tissue is excised in 4 patients and histological examination revealed sections of vas deferens and epididymis. One of the patients underwent inguinal exploration and orchidectomy for assumed testicular atrophy else-where but histological examination revealed vas deferens and epididymis without any sign suggesting an atrophic testis. An intrabdominal testis was found incidentally in this patient and he underwent 2 additional procedures for orchidopexy. Discussion Although epididymo-testicular anomalies are common in boys with undescended testis, nonunion is the rarest type of this anomaly. Similar cases are reported in the literature as simple fusion anomalies with indefinite clinical significance or even polyorchidism although no accessory testis could be demonstrated. However, the scrotal nubbin tissue which actually contains epididymis and vas is a potential decoy and may result in missing of the proximal testis if regarded as a sign of testicular atrophy and further evaluation is obviated. As this is retrospective study, actual incidence of the condition is yet to be determined. Conclusion A scrotal nubbin tissue may be secondary to epididymo-testicular nonunion as well as testicular atrophy. As feasibility of radiological imaging studies are limited, a laparoscopic exploration may be considered to confirm or to exclude a separate testis in patients with scrotal nubbin. Prospective studies are needed to evaluate the actual incidence of the condition and gain-loss analysis of laparoscopic exploration [GRAPHICS] .