CD30 (Ki-1)-positive large-cell cutaneous T-cell lymphoma with secondary xanthomatous changes after radiation therapy.

A 72-year-old woman with a large mass on her forehead was found to have primary cutaneous CD30-positive large T-cell lymphoma and was treated with radiation therapy. Five weeks after the completion of radiation therapy, a large, yellow plaque developed on the forehead. Histopathologic examination showed numerous xanthoma-like cells with clear and foamy cytoplasm that infiltrated the upper and mid dermis with no residual lymphoma. To our knowledge, this is the first report of xanthomatous change after radiation therapy for primary cutaneous CD30-positive large cell lymphoma. We believe that the xanthomatous change after radiation therapy probably was caused by lysis of radiosensitive lymphoma cells and histiocytic scavenging of lipid-membrane debris.