Recurrent Atypical Fibroxanthoma Versus Malignant Fibrous Histiocytoma

Atypical fibroxanthoma (AFX) has been characterized variously as a benign noninvasive neoplasm with rare recurrence. We report 2 cases of recurrent AFX. There is ongoing controversy over the diagnosis of AFX versus malignant fibrous histiocytoma (MFH) in the clinical context of recurrent AFX. Histopathologic diagnosis of fibrohistiocytic neoplasms can be quite challenging and small foci of cancer can be easily overlooked. This is particularly problematic when scarring associated with recurrent tumors is present. The utility of en face sections, as utilized in Mohs micrographical surgery, and the employment of immunohistochemical stains may be helpful in diagnosis. Recurrence of AFX can occur but is difficult to distinguish from MFH.