Acute myelogenous leukemia in children: results of the cooperative BFM-78 therapy study after 3 3/4 years

Between December, 1978, and October, 1982, 151 children with acute myelogenous leukemia from 30 pediatric clinics entered the cooperative study. The treatment consisted of a 10-week intensive induction therapy and a subsequent maintenance therapy, which is terminated for children in complete continuous remission after 2 years. The induction treatment during the first 4 weeks consisted of a combination of prednisone, 6-thioguanine (TG), vincristine, adriamycin (ADR) and cytosine-arabinoside (ARA-C). In the following 4 weeks i.v. cyclophosphamide, i.th. methotrexate and prophylactic cranial irradiation were administered in addition to TG, ARA-C and ADR. 119 of the 151 patients (79%) achieved complete remission. 13 children (9%) died of early hemorrhages, 2 of them before onset of therapy. 5 patients died initially of other complications, another 6 after remission has been achieved. 13 children did not respond or responded poorly to the induction therapy. So far, 40 relapses occurred, mainly in the bone marrow. In 6 relapses the central nervous system was involved. The probability for a continuous complete remission for the total group is 0.41 +/- 0.05 (life table analysis) and for the total group 0.56 +/- 0.06 after 45 months. The corresponding probability for survival after 46 months are 0.43 +/- 0.06 for the remission group. The risk for occurrence of early fatal hemorrhages was higher in children with acute monocytic leukemia than in the other morphological subtypes. An initial leukocyte count of more than 100,000/microliters was found significantly more often in patients who did not achieve remission (early deaths and nonresponders) than in children of the remission group. So far, no factors could be identified which influence the risk for relapse. The present results of the study allow the conclusion, that with the applied treatment strategy it is possible to achieve not only in a high portion of children with AML remission but also to improve the chances for long-time remission and perhaps cure.