RESULTS AND EXPERIENCE WITH A MODIFIED BF M-PROTOCOL FOR THE TREATMENT OF RELAPSED CHILDHOOD ACUTE LYMPHOBLASTIC-LEUKEMIA IN EAST-GERMANY

Between 1988 and 1990, 55 patients with first relapses of acute lympho blastic leukemia (ALL) were treated with a modified BFM-protocol (ALL REZ I/88). The patients were divided according to time and site of rel apse: relapses with bone marrow involvement up to 6 months after stopp ing front line therapy (group A), relapses with bone marrow involvemen t beyond 6 month after therapy (group B) and isolated extramedullary r elapses at any time (group C). During therapy the patients received al ternating courses of polychemotherapy including infusions of intermedi ate dose methotrexate (1 g/m2 in 36 hours). The maintenance treatment consisted of daily oral thioguanine and biweekly intravenous (IV) MTX. The overall second remission rate was 89% (group A: 90%, group B: 86% , group C: 93%) and the probability of event free survival (EFS) at 4 years is 0.28 +/- 0.13 (group A: 0.22 +/- 0.12, group B: 0.24 +/- 0.18 , group C: 0.57 +/- 0.15). We conclude, that with the treatment regime n applied, long lasting second remission can be achieved in about one third of patients even after intensive front line therapy. The most un favourable prognoses were seen in patients with early bone marrow rela pses (group A).