Objective: We report a case of supernumerary testis, a rare anomaly with only around 100 cases reported in the literature.
Methods: We describe the case of a 26-year-old man who consulted for a left paratesticular tumor. Physical examination and ultrasound showed a 2-cm nodular lesion over the left epididymis. The lesion was confirmed as supernumerary testis by surgical examination and biopsy and was subsequently excised, given the malignancy potential.
Results: The supernumerary testis was evaluated using two standard classifications, one assessing function and embryological development, and the other assessing topography, anatomy, and reproductive potential.
Conclusions: The differential diagnosis for an intrascrotal mass should include the possibility of a supernumerary testis; hence, surgical examination and biopsy are necessary. Supernumerary testes should be excised in the case of pain, dysplasia, or in situ carcinoma, or whenever the biopsy is inconclusive.