Allogeneic bone marrow transplantation for Langerhans' cell histiocytosis.

A group of proliferative diseases of the epidermal Langerhans' cells are commonly referred to as Langerhans' cell histiocytosis (LCH). A small number of the patients with this disease face an unfavorable disease course despite chemotherapy and radiation therapy. In LCH patients with a poor prognosis, allogeneic bone marrow transplantation (BMT) could be the appropriate treatment with proven antiproliferative effects and may be able to repopulate the recipient with stem cell-derived Langerhans' cells from the donor or correct the presumed underlying immunodeficiency. An LCH was diagnosed in a 15-year-old boy with multiple osteolytic lesions, anemia, and diabetes insipidus centralis. Repeated flare-ups of the disease had necessitated several courses of conventional chemotherapy including cyclophosphamide (CY), prednisolone (P), 6-mercaptopurine (6-MP), vincristine (VCR), and additional local irradiation without stable remission. Three years after first being diagnosed with LCH the patient underwent high-dose chemotherapy-radiation therapy followed by allogeneic BMT from his human lymphocyte antigen (HLA)-identical brother. Currently, he is alive and well and has been disease-free for more than 41 months after BMT.