Malignant histiocytosis in childhood. Clinical features and therapeutic results by combination chemotherapy.

Ten children, four males and six females, with malignant histiocytosis were treated from July 1980 to July 1984. None of them had an affected sibling with a similar disorder. Septic-type fever, hepatosplenomegaly, lymphadenopathy, pulmonary infiltration, and disseminated intravascular coagulation were common signs and symptoms, and convulsion occurred in four cases. The diagnosis was made from bone marrow smears in all cases. In five cases, biopsy or autopsy specimens confirmed the diagnosis. In five cases studied, proliferating histiocytes in lymph nodes were demonstrated to be S100 protein-positive. All patients were treated with adriamycin, cyclophosphamide, vincristine, and prednisone (ACOP). Complete response was achieved in four patients after two to three courses of ACOP, and another case attained complete remission after further drug treatment. The five complete responders are now alive without evidence of disease after 23-48 months from the onset. Among partial and no responders, four died within 3 months and one has been alive with disease for 2 months. Bone marrow aspiration is useful for prompt diagnosis, and early treatment with intensive combination chemotherapy improves the prognosis of malignant histiocytosis in childhood.