Plexiform Schwannoma of the Penis: A Rare Subtype of Genital Schwannoma

Abstract

Schwannomas are benign, encapsulated neurogenic tumors which present in diverse histological subtypes despite the limited variety of their cellular constituents. These include the cellular, ancient, cystic, epithelioid, melanotic, psammomatous, schwannoma with pseudoglandular elements, and plexiform varieties. The plexiform schwannoma (PS) represents 4.3% of all schwannomas. These lesions are commonly encountered in the head and neck region and are extremely rare in the penis. To the best of our knowledge only 34 cases of penile schwannomas have been reported and this is the 3rd case of plexiform penile schwannoma. A 39-year-old patient presented to our andrology outpatient clinic complaining for two painful penile nodules. The lesions were located on the dorsum of the penile shaft. His medical history was insignificant for penile trauma and sexual transmitted diseases. The masses measured 2x1 cm and 0.5x1 cm. After sonographic and magnetic resonance evaluation the patient was admitted to theatre and underwent topical resection of the lesions. Histopathology revealed plexiform schwannoma. Postoperatively, penile tenderness and hyperesthesia ensued which was managed with pregabalin administration and topical corticosteroids. Plexiform schwannomas are rare in the penile region. Surgical excision is inevitably the only way to diagnose and treat the lesions. They must be differentiated by a variety of malignant and benign clinical conditions. Topical excision suffices for oncological control and allows for acceptable functional outcomes.