Sclerosing Epithelioid Fibrosarcoma

Sclerosing epithelioid fibrosarcoma is a rare histologic variant of fibrosarcoma characterized by an epithelioid phenotype in a background of dense hyalinized stroma. Due to its rarity, the diagnosis of this entity often is difficult, and this lesion can be confused with a variety of neoplasms including carcinoma, lymphoma, and other soft tissue sarcomas. Immunoreactivity for vimentin only and ultrastructural evidence of fibroblastic differentiation can aid in the differential diagnosis. This tumor is a high-grade sarcoma that typically follows a malignant clinical course. Sclerosing epithelioid fibrosarcoma should be considered at the high-grade end of the spectrum of the fibrosing fibrosarcoma family of tumors.