Complete Response to Thalidomide and Dexamethasone in a Patient With Necrobiotic Xanthogranuloma Associated With Monoclonal Gammopathy: A Case Report and Review of the Literature

Necrobiotic xanthogranuloma (NXG) was first described in 1980 by Kossard and Winkelmann in an article in which they discussed 8 patients with xanthomatous plaques who were noted to have monoclonal gammopathy, predominantly of the Ig(immunoglobulin)G-κ type.1 Since then more than 50 patients with this disorder have been described, with approximately 80% of them having an associated monoclonal gammopathy.We describe the first case, to our knowledge, of NXG with associated monoclonal gammopathy treated with thalidomide plus dexamethasone, achieving complete resolution of the skin lesions and sustaining response more than 3 years after treatment.