A giant paratesticular leiomyoma presenting as a painless scrotal mass: a case report

Leiomyomas are benign smooth muscle tumors that are rarely found in the genitourinary tract. Paratesticular leiomyomas are exceedingly uncommon, representing a small subset of intrascrotal neoplasms. Intrascrotal tumors comprise a heterogeneous group of lesions, with paratesticular tumors accounting for only about 5% of all testicular masses. Awareness of this rare entity is essential, as it may clinically mimic malignant testicular tumors, potentially leading to unnecessary radical orchiectomy.

We present a case of a 55-year-old male who developed a progressively enlarging intrascrotal mass, ultimately diagnosed as a paratesticular leiomyoma. The lesion arose from soft tissue adjacent to the testis and presented as a firm, painless scrotal swelling. Imaging revealed a well-circumscribed, homogeneous lesion without invasion into the testis. Surgical excision was performed, and histopathological analysis confirmed the diagnosis of leiomyoma, showing interlacing bundles of smooth muscle cells without atypia or mitotic activity.

Paratesticular leiomyomas originate from the smooth muscle elements of the spermatic cord, epididymis, tunica albuginea, or surrounding tissues. They are benign, slow-growing lesions that may be clinically indistinguishable from malignant testicular tumors. Imaging modalities, including ultrasound and MRI, are useful for preoperative assessment but cannot reliably differentiate benign from malignant lesions. Definitive diagnosis requires histopathological examination demonstrating typical spindle-shaped cells, minimal atypia, and the absence of necrosis or mitotic figures. Complete local excision provides both diagnostic confirmation and curative management.

Although rare, paratesticular leiomyoma should be considered in the differential diagnosis of paratesticular and intrascrotal masses. Accurate diagnosis, based on histopathological examination, prevents overtreatment. Surgical excision remains the treatment of choice and is associated with an excellent prognosis and minimal recurrence risk.