A case of subcutaneous malignant fibrous histiocytoma circumscribed by fibrous tissue.

We report a case of malignant fibrous histiocytoma (MFH) located in the subcutaneous tissue on the right axilla. We excised the tumor sufficiently beyond the clinical margin. It was pathologically diagnosed as a storiform-pleomorphic type of malignant fibrous histiocytoma almost completely circumscribed by fibrous tissue, including fascicles of fibroblasts; this is a rare histological picture. The tumor has not recurred for three years. Although MFH frequently undergoes metastasis, the circumscribed-type subcutaneous MFH characteristic of superficiality and of histologically well-defined structure seems to have a relatively more favorable prognosis after adequate radical excision.