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Atypical Fibroxanthoma: A Review of the Literature

BACKGROUND Atypical fibroxanthoma (AFX) is an uncommon superficial fibrohistiocytic tumor. It was originally described as a low‐grade dermal tumor of atypical spindle cells, but this view has changed, and it is generally considered to be a tumor of intermediate malignant potential. OBJECTIVE To review the current literature on AFX pertaining to epidemiology, pathogenesis and etiology, clinical presentation, histology, immunohistochemistry, prognosis and follow‐up, and treatment. MATERIALS AND METHODS Extensive literature review was conducted using OVID Medline and Pubmed searching for articles relating to AFX. RESULTS AFX typically presents as a red or pink papule or nodule on the head or neck of an elderly man. The pathogenesis is most commonly related to ultraviolet radiation. It can clinically mimic other cutaneous malignancies and histologically can mimic squamous cell carcinoma, desmoplastic melanoma, and undifferentiated pleomorphic sarcoma. Immunohistochemistry is important in making the distinction. The prognosis is generally excellent, although there are rare cases of metastatic disease. There is a higher cure rate with Mohs' micrographic surgery than with wide local excision. CONCLUSIONS People with AFX generally have had significant ultraviolet radiation exposure. They should be examined at least every 6 months for recurrence, metastasis, and the development of additional skin cancers. The authors have indicated no significant interest with commercial supporters.