Abstract: | The study evaluates the efficacy of seven drug systemic therapy and three drug intrathecal treatment in children with acute lymphoblastic leukemia (ALL). Three hundred and thirty-five children with ALL treated at six hematological centers in Poland were divided into two groups: standard group and high risk group according to the BFM score method. Ninety-two children estimated as high risk patients diagnosed between 1978 and 1981 were treated according to the Polish Children's Leukemia/Lymphoma Study Group (PCLSG) program adopted from LSA2L2 regimen. The patients received prednisone, vincristine, adriamycin and cyclophosphamide as remission induction treatment, followed by cytarabin and 6-thioguanine given as consolidation therapy. The central nervous system prophylaxis consisted of cranial irradiation and intrathecal methotrexate, cytarabin and hydrocortisone. In maintenance phase, three different drug combinations were given as intermittent therapy. The total duration of therapy was 2.5 years. The life table analysis showed a 38% disease free survival and 50% complete continuous remission (CCR) for the total group of patients. A relatively high incidence of CNS relapse was observed. These results indicated that the regimen applied was not satisfactorily effective for the increased risk of ALL. Three of seven evaluated prognostic indices—age, mediastinal mass and cytochemical features—were significantly associated with probability of survival of the patients with protocol applied. Some other therapy proposals are discussed. |