Intensive conditioning regimen for bone marrow transplantation in children with high-risk haematological malignancies.

Between September 1987 and May 1991, 21 children aged 10 months to 15 years (median 9 years) underwent bone marrow transplantation (BMT) for advanced haematological malignancies using a conditioning regimen consisting of total body irradiation (TBI), etoposide 1.8 g/m2 by continuous infusion, and cyclophosphamide 2 g/m2 on 3 consecutive days. The patients included 14 with acute lymphoblastic leukaemia (ALL), 1 with chronic myeloid leukaemia (CML), 1 with juvenile CML, 4 with non-Hodgkin's lymphoma and 1 with acute nonlymphocytic leukaemia. Eleven had an allogeneic BMT from an HLA-matched sibling, and 1 from an unrelated donor. Nine patients received 4-hydroperoxycyclophosphamide purged autologous marrow. Median time to myeloid engraftment (ANC > 500/microliters) was 19 days in allogeneic BMT patients and 28 days in autologous BMT patients (P < .01). Mucositis was the major regimen-related toxicity (RRT). GI toxicity in the form of diarrhoea affected ten patients and five had veno-occlusive disease of the liver. Two patients had mild bladder toxicity and one died of renal toxicity. There was no CNS or cardiac toxicity. There was no significant difference in the incidence of toxicity according to the type of BMT (autologous or allogeneic), total dose, or sequence of TBI. With a median follow-up of 44 months, ten patients are alive (6/12 allogeneic BMT patients and 4/9 autologous BMT patients). Of the 11 deaths, four were related to toxicity (2 aspergillus, 1 haemorrhage following liver biopsy, and 1 from haemolytic-uraemic syndrome), and 4/12 allogeneic and 4/9 autologous BMT patients died from relapsed disease. This conditioning regimen is well tolerated in children, demonstrating mild and reversible RRT.