Solitary Fibrous Tumors

Abstract

Solitary fibrous tumors (SFTs) are a subtype of soft tissue sarcoma with fibroblastic differentiation. SFTs typically occur in patients between ages 50 and 70 and most commonly develop in the pleural space or abdomen, although they have been described in virtually every body site. Cross-sectional imaging (CT or MRI) is useful to help characterize the tumor, and core-needle biopsy is critical to obtain tissue for diagnosis. Definitive diagnosis is now made by immunohistochemical expression of STAT6, which results from a key genetic aberration (NAB2-STAT6 fusion) recently identified in SFTs. For patients with SFT, surgical resection is the mainstay of treatment. Current data suggest some benefit with adjuvant radiation therapy and systemic therapy; however, further studies are needed. After treatment, surveillance in SFT patients is important, and late recurrences have been reported. Although these tumors are generally indolent, with low metastatic potential, a subset of cases will demonstrate aggressive behavior. Simple risk assessment models have been developed to help predict clinical behavior. Novel predictive biomarkers and disease biology–driven targeted therapy options are needed. This review contains 4 Figures, 2 Tables and 37 references Key words: cellular angiofibroma, characteristic chromosomal translocation, dermatofibrosarcoma protuberans, Doege-Potter syndrome, hemangiopericytoma, perineuroma, preoperative angioembolization, schwannoma, solitary fibrous tumors