Treatment strategy for different risk groups in childhood acute lymphoblastic leukemia: A Report From the BFM Study Group.

Development of effective treatment programs for childhood acute lymphoblastie leukemia (ALL) has led to marked improvement of prognosis. The proportion of patients remaining in first remission for at least 5 years is generally estimated to be in the range of 50% once remission is achieved (Frei and Sallan 1978; Riehm etal.1980;Robisonetal.1980). Since remission rates have been shown to be 90%-95 % with currently used induction therapy, successful induction of remission is no longer an essential problem. Nevertheless, the quality of remission is apparently unsatisfactory in about one-half of the patients, eventually resulting in recurrence of the disease. Predictors of outcome have been defined and include white blood count (WBC), sex, thymic involvement, central nervous system disease at diagnosis, immunologie markers, unfavorable age, and blast cell morphology (Dow et al. 1977; Henze et al. 1979; Mathe et al. 1971; Sallan et al. 1978; Simone et al. 1975; Wagner and Baehner 1979; Working Party on leukemia in Childhood 1978); but attempts to adapt the therapeutic strategy to the presence of factors associated with a poor prognosis have not been able to enhance significantly therapeutie results. The approach of the BFM study group with the concept of intensive multidrug remission induction gives hope for an overall 75 % relapse-free survival in childhood ALL.