AML patients with Down syndrome have a high cure rate with AML-BFM therapy with reduced dose intensity

Despite improved prognosis in acute myelogenous leukaemia (AML) children with Down syndrome (DS), therapy-related toxicity remained a problem. We compared 67 DS patients from study AML-BFM 98 with 51 DS patients of the previous study AML-BFM 93, and the non-DS groups of both studies. Compared to non-DS patients, DS patients were treated with reduced anthracycline doses, without high-dose cytarabine/mitoxantrone and without cranial irradiation. AML-DS patients were in median 1.8 years old, and 102/118 (86%) showed the typical morphology of acute megakaryoblastic leukaemia. In study 93, seven DS patients did not receive AML-specific chemotherapy, and treatment modifications were more common. Results improved significantly for patients treated in study 98 with a 3-year survival of 91 +/- 4 vs 70 +/- 7% in study 93 (P=0.001). There were no differences in outcome concerning the age groups 0-<= p2 and 2-<= p4 years (event-free survival for treated patients 0-<= p2 years 83 +/- 4%, 2-<= p4 years 81 +/- 7%). The cumulative incidence of relapses was significantly lower in DS (7 +/- 3%) than in non-DS patients (28 +/- 7%). Therapy-related toxicity was generally lower in DS patients treated according to study 98. We conclude that a standardised and dose-reduced treatment schedule including the main components of AML treatment is advisable for AML children with DS.