Intrascrotal Extratesticular Schwannoma: A Rare Cause of Scrotal Mass.

Background: Schwannoma, also known as neurinoma, is the most common tumor of the peripheral nerves. Intrascrotal extratesticular schwannoma, which is not associated with schwannomatosis and neurofibromatosis-2, is a very rare entity, and few cases have been reported in the literature. In this paper, we have reported a case of extratesticular schwannoma, an extremely rare cause of scrotal mass, with ultrasound (US) and magnetic resonance imaging (MRI) findings.

Case Report: A 22-year-old male presented with painless left scrotal swelling. Scrotal US showed an extra-testicular heterogeneous hypoechoic mass with the lobulated contour in the inferior part of the scrotum. Scrotal MRI demonstrated well-defined extratesticular mass, which showed heterogeneous hypointense T2-weighted images compared to testis parenchyma. On contrast-enhanced images, the mass showed mild-to-moderate enhancement. The patient underwent surgery with the preliminary diagnosis of benign intrascrotal extratesticular mass. The lesion was removed with preservation of the testicles by urologists, and the final diagnosis was made as scrotal schwannoma by histological and immunohistochemical examination.

Conclusion: Although there is no specific imaging finding of scrotal schwannoma, MRI can be used as a guide to surgery by helping to accurately determine whether the lesion is intra- or extratesticular. In addition, radiologists and urologists should keep schwannoma in mind in the differential diagnosis in the presence of an intrascrotal extratesticular mass.