FAILURE OF LATE INTENSIFICATION THERAPY TO IMPROVE A POOR RESULT IN CHILDHOOD LYMPHOBLASTIC-LEUKEMIA

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  • 1 January 1984
    • journal article
    • research article
    • Vol. 44  (8) , 3593-3598
Abstract
A clinical study, begun in 1975, tested the efficacy of early and delayed intensification treatments in children with acute lymphoblastic leukemia. Regardless of presenting features, all patients received 4 wk of conventional induction therapy with daily prednisone and weekly vincristine and duanorubicin. One-third were randomized to receive, in addition, 2 doses of asparaginase during induction therapy, while another 1/3 received 4 doses of both asparaginase and cytarabine after remission induction. Preventive CNS therapy uniformly included 2400 rad cranial irradiation and 5 doses of intrathecal methotrexate. Remissions were maintained with daily p.o. [oral] mercaptopurine and weekly i.v. methotrexate. Of the 277 assessable patients, 254 (92%) entered complete remission, and 102 (37%) remain clinically free of leukemia for 4.6-8.0 yr (median, 6.3 yr). The 3 treatment groups showed no significant differences in either remission induction rate or outcome, even when the analysis was based on risk assignment. A late intensification phase of therapy, added to the maintenance protocol for 65 patients who were in continuous complete remission for 14-30 mo., failed to extend remission durations, as judged from statistical comparison with matched controls (P = 0.84). When tested as a time-dependent covariate in the Cox proportional-hazards model, delayed intensification again showed no important effect on duration of complete remission. Limited early or aggressive late intensification of therapy, as described here, does not improve outcome in childhood acute lymphoblastic leukemia.