title: Ossifying fibromyxoid tumor of soft parts. A clinicopathological analysis of 59 cases.
abstract: We describe 59 cases of a microscopically unique neoplasm that has not been previously reported. The tumor almost exclusively affected adults (range 14-79 years) and had a male predominance (38 men and 21 women). It presented in most cases as a small, painless, well-circumscribed mass (median, 4 cm) in subcutis or muscle. It occurred chiefly in the upper and lower extremities (40 cases) and less frequently in the trunk (11 cases) and the head and neck region (eight cases). Microscopically, the tumor was partly lobulated and composed of small, round cells that had vesicular nuclei and indistinct cytoplasm. Typically, the cells were arranged in a cord- or nestlike pattern within a myxoid matrix that frequently showed transitions toward hyaline fibrosis and focal osteoid formation. In about two-thirds of the cases, the cells contained immunoreactive S-100 protein. An additional typical feature, seen in 48 (81%) of the 59 cases, was the presence of an incomplete shell of mature bone in the capsular region of the tumor. Follow-up information, available in 41 cases, revealed that 11 patients (27%) experienced one or more recurrences. One patient with three recurrences developed a second tumor in the opposite thigh, presumably a metastasis. None of the patients died of the tumor, but three died of causes unrelated to the disease. Although the histogenesis is uncertain, cartilaginous or neural origin seem to be most likely. Until this issue is resolved, we prefer the descriptive and less committal designation of "ossifying fibromyxoid tumor of soft parts."
authors: Armed Forces Institute of Pathology (AFIP), Department of Soft Tissue Pathology, Washington, D.C. 20306-6000.
authors: F M
authors: FM
authors: Enzinger
authors: S W
authors: SW
authors: Weiss
authors: C Y
authors: CY
authors: Liang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002812:Chondroma / Q000032:analysis / Q000473:pathology / Q000648:ultrastructure; D002813:Chondrosarcoma / Q000032:analysis / Q000473:pathology / Q000648:ultrastructure; D005260:Female; D005350:Fibroma / Q000032:analysis / Q000473:pathology* / Q000648:ultrastructure; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009999:Ossification, Heterotopic; D009418:S100 Proteins / Q000032:analysis; D012983:Soft Tissue Neoplasms / Q000032:analysis / Q000473:pathology* / Q000648:ultrastructure
chemical_list: D005904:Glial Fibrillary Acidic Protein; D009418:S100 Proteins; D007633:Keratins