Atypical fibroxanthoma of the external ear in a cardiac transplant recipient: case report and the causal role of the immunosuppressive therapy.

Atypical fibroxanthoma (AF) is an unusual cutaneous fibrohistiocytic tumour that is most commonly found in ENT sun-exposed areas of elderly males. Cardiac transplant patients have an increased incidence of multiple cutaneous neoplasms, but the AF is uncommon. Although this neoplasm is benign, it may mimic spindle cell carcinoma, squamous cell carcinoma, melanoma and soft tissue sarcoma on histologic examination. Immunohistochemical stains for cytokeratin, alpha-1-antichymotrypsin, S100 protein and vimentin may be helpful in differential diagnosis. AF rarely recur or metastasize, if wide excision has been performed. We present a case of a cardiac transplant recipient who developed, after multiple cutaneous squamous tumours, an AF of external ear following the prolonged immunosuppressive treatment with cyclosporin.