Solitary Fibrous Tumor of the Scrotum: A case report

ABSTRACT

Solitary fibrous tumor (SFT) is a rare spindle cell neoplasm that usually arises in the pleura and has been recently reported from unusual locations. We present a case of SFT that occurred in the scrotum. The patient was a 38-year-old man who presented with a painless, left, scrotal mass of five years' duration. Scrotal sonography and pelvic CT scan showed a soft-tissue mass of 11 cm in diameter. The resected tumor measured 11 8 7 cm and was well demarcated from the surrounding soft tissue. The cut surface revealed homogenously grayish-white and gelatinous appearance. No hemorrhage or necrosis was found. Microscopically, the tumor showed hypercellular spindle cell areas intermixed with hypocellular areas lying in a myxoid or collagenous stroma. The spindle cells had no mitosis or low mitotic figures, and little or no nuclear atypia. They exhibited a variety of growth patterns, including "patternless" pattern, and a prominent vasculature with hemangiopericytic pattern. Vimentin, CD34, and bcl-2 protein immunoreactivity were observed. Characteristic histologic and immunohistochemical features of this lesion were consistent with SFT. To arrive at a correct diagnosis of this lesion, especially when it occurs in unusual sites, immunohistochemical study including CD34 & bcl-2 protein is required in addition to characteristic histologic features.