Phase I and II study of AMSA in childhood tumours.

Twenty-nine children with tumours that had failed to respond to conventional therapy have been treated with AMSA. There were 16 patients with haematological malignancies in whom treatment was initiated at 25 mg/m2 for 3 days, increasing to 150 mg/m2 for 5 days. There were one complete and four partial remissions in these patients, all of whom had received at least 500 mg AMSA/m2. Thirteen children with solid tumours were treated. They received single doses of 120 mg/m2 initially, increasing to 100 mg/m2 for 5 days. No complete or partial responses occurred, but some antitumour activity was noted in neuroblastoma and retinoblastoma. Dose-related severe bone marrow toxicity occurred, but gastrointestinal and other toxicity was mild. An additional patient with T cell lymphoma, who received AMSA prior to a successful autologous bone marrow transplant, is described. AMSA is an active drug in childhood leukaemia. Further studies at the maximum tolerated dose are needed to assess enough patients with any single solid tumour type. In particular, the response of neuroblastoma warrants further study. Investigation of the use of AMSA either prior to bone marrow transplantation in leukaemia or in association with autologous marrow transplant in neuroblastoma and other solid tumours may be of value.