Acute lymphoblastic leukemia in children. Results of a protocol including bone marrow transplantation during the first remission in high-risk forms for relapse

Ninety-two previously untreated children with ALL were admitted to the same institution between November 1984 and November 1988. According to early prognostic factors, patients were divided into 3 groups: group 1 at "low risk" for relapse (n = 18), group 2 at "intermediate risk" (n = 62) and group 3 at "high risk" (n = 12). Every patient received an 8 week-long induction chemotherapy; after CNS prophylaxis, groups 1 and 2 children received a consolidation chemotherapy and then a classical maintenance treatment. Group 3 patients were selected to receive a bone-marrow transplantation during their first remission because of the presence, at diagnosis, of at least one of the following criteria: hyperleukocytosis greater than 100,000 (7 cases), translocation t(1;19) and t(4;11) (2 cases), adolescents (2 cases), no remission at day 30 (2 cases). Ninety-one of 92 children achieved a complete remission and none died during induction therapy. Probability of leukemia-free survival at 4 years is 73 +/- 7% for the whole patient population and 95%, 71% and 60% for patients of groups 1, 2, and 3 respectively. Persistence or disappearance of leukaemic cells in bone marrow after the initial 15 days of chemotherapy appears to influence the probability of a leukemia-free survival.