malignant fibrous histiocytoma


ma·lig·nant fi·brous his·ti·o·cy·to·ma

a sarcoma of variable malignant potential, occurring most often in the extremities and retroperitoneum; often recurs locally after resection, less often metastasizes; shows partial fibroblastic and histiocytic differentiation with a variable storiform pattern, myxoid areas, and giant cells.

malignant fibrous histiocytoma

A malignant tumour consisting of mitotically active spindled cells arranged in a storiform pattern. Malignant fibrous histiocytoma is no longer considered an entity a sui generis, given that many MFHs proved to be melanomas, poorly-differentiated carcinomas and lymphomas when examined by immunohistochemistry.
Reclassification of MFH types
• Angiomatoid type malignant fibrous histiocytoma—now Angiomatoid fibrous histiocytoma.
• Inflammatory malignant fibrous histiocytoma—now Inflammatory de-differentiated liposarcoma.
• Giant cell malignant fibrous histiocytoma, high grade—now Giant cell-rich extraskeletal osteosarcoma.
• Giant cell malignant fibrous histiocytoma, low grade—now Giant cell tumour of soft tissue.
• Malignant fibrous histiocytoma, myxoid type—now Myxofibrosarcoma.

malignant fibrous histiocytoma

A pleomorphic mesenchymal malignancy of older adults, which affects deep soft tissues–involving muscle 60% or fascia 20% of the lower–50% and upper–20% extremities, retroperitoneum 15% and abdominal cavity; MFH metastasizes to the lung 80%, lymph nodes 30%, liver, bone DiffDx Sarcomas, pleomorphic or primitive carcinoma, bizarre melanoma Prognosis 40-65% of tumors recur; 25-50% metastasize

ma·lig·nant fi·brous his·ti·o·cy·to·ma

(mă-lig'nănt fī'brŭs his'tē-ō-sī-tō'mă) A deeply situated tumor, especially on the extremities of adults, frequently recurring after surgery and metastasizing to the lungs; shows partial fibroblastic and histiocytic differentiation with a variable storiform pattern, myxoid areas, and giant cells.