Typical leiomyoma of the scrotum: A rare case report

Scrotal leiomyomas are benign tumors arising from the dartos layer of the scrotal wall. The exact cause of this tumor is not yet clear. Malignant transformation to leiomyosarcomas has been reported.

A 52-year-old male who complained of a painless lump on the right side of the scrotum that lasted 12 years. Physical examination revealed a single, firm, and non-tender, mobile lump on the anterior aspect of the right scrotum. Both testes were normal and no inguinal lymph nodes could be palpated. Ultrasound scan of the scrotum showed a 40 mm × 20 mm hypoechoic, poorly vascular lesion in the scrotum. Under spinal anesthesia, the mass has been excised. Histopathological and immunohistochemical findings were consistent with the diagnosis of scrotal leiomyoma.

Leiomyomas may originate from any location in the genitourinary system where there is smooth muscle. Scrotal smooth muscle tumors can be categorized into Leiomyomas, atypical or symplastic leiomyomas, which are not hypercellular and lack mitotic activity, and leiomyosarcomas. Ultrasound is the first-line imaging investigation in patients with suspected scrotal masses. Typical leiomyomas and atypical ones behave similarly. Therefore, they are managed only with surgical excision, while leiomyosarcomas need a wide 3-5 cm margin resection. Both recurrence and malignancy have been described. Close follow-up is required to detect recurrence.

Scrotal leiomyoma is a rare benign mesenchymal tumor of the middle-aged men. The current report describes the clinical and histopathological characteristics to help reduce erroneous diagnoses of this rare tumor.