Drug therapy for the treatment of Langerhans cell histiocytosis.

Langerhans cell histiocytosis results from the abnormal accumulation of a class of dendritic cells normally found in the skin, which proliferate in many organ systems along with lymphocytes, macrophages and eosinophils. Standard therapy for Langerhans cell histiocytosis includes vinblastine and prednisone with or without methotrexate and mercaptopurine, depending on the extent of disease. Effective therapies for patients unresponsive to the above include cytosine arabinoside and cladribine. Thalidomide has proven useful for patients with Langerhans cell histiocytosis of the skin and/or bone. Emerging therapies include the use of monoclonal antibodies against the CD1a or CD52 epitopes found on Langerhans cells. Specific therapies directed against the cytokines that are apparently critical to the abnormal proliferation have not yet been defined.