Solitary fibrous tumor of soft tissue

초록

Solitary fibrous tumor is a rare spindle cell neoplasm of adults that ususally arises in the pleura, recently reported in a variety of sites, including other serosal surfaces: the peritoneum and pericardium, and nonserosal sites: the breast, thyroid, lung, mediastinum, orbit, paritid gland, upper respiratory tract, and nasal cavity and paranasal sinuses. Recently, several cases of solitary fibrous tumor have been reported in somatic soft tissues unrelated to serosal surfaces. The tumors occuring at soft parts are poorly recognized and often confused with other neoplasm. A 38-year-old woman presented with a slowly growing subcutanous mass on left shoulder area. The excised mass was not encapsulated but well circumscribed and measured 3.5x3.0c1.5cm. the cut surface showed whitish-gray, smooth fibrotic appearance with focal myxoid change and elastic hard consistency. Histologically, the tumor was composed of a haphazard proliferation of plump to spindled cells with scant indistinct cytoplasm separated by thick bands of hyalinized collagen. Cellularity was variable, with a admixture of hypercellular and hypocellular areas. The tumor cells showed very little pleomorphism. Mitotic figures are not seen. Necrosis or hemorrhage was not seen. Vimentin and CD34 immunoreactivities were observed in many spindle cells of tumor. Solitary fibrous tumors seem to represent distinct mesenchymal neoplasms that requires us to identify their unusual location other than the pleura. SFTs should be separated from other spindle cell sarcomas, with which they can be confused.