Improved outcome for acute lymphoblastic leukemia in children of a developing country: Results of the Chilean national trial PINDA 87

Background. The National Chilean Pediatric Oncology Group, PINDA, reports t he first prospective, nonrandomized trial for acute lymphoblastic leukemia (ALL), using a modified version of the Berlin-Franfurt-Munster protocol (AL L BFM 86). The aim of this study was to classify immunophenotypes, to decre ase cranial irradiation, and to assess whether this protocol would improve the survival rate. Procedure. From June, 1987, to June, 1992, 444 unselecte d children were diagnosed with ALL. Of them, 425 were evaluable. Therapy wa s stratified by risk. Standard-risk (SR) and high-risk (HR) patients receiv ed protocols I, M, II, and maintenance therapy. Very-high-risk (VHR) patien ts received protocol E instead of protocol M. All patients received a preph ase treatment consisting of prednisone and intrathecal methotrexate (MTX). HR and VHR patients received cranial irradiation (12-18 Gy). The following changes were made to the ALL BFM 86 protocol: in protocol M, MTX 1 g/m(2) i nstead of 5 g/m(2); in protocol E, citarabine 1 g/m(2) instead of 2 g/m(2); mithoxantrone and ifosfamide were substituted by teniposide and cyclophosp hamide. Results. Immunophenotypes: pre-B-ALL, 14%; common ALL, 67.4%; pre-B -ALL, 4.3%; T-ALL, 10%; undifferentiated leukemia (AUL), 4.3%. The overall 5-year event-free survival (EFS) rate was 60% +/- 2% (SE). The 5-year EFS r ate for each risk group was: SR 75%, HR 62%, VHR 28%, with a median follow- up of 6.5 years (range 4.5-9.5 years). The cumulative incidence of central nervous system (CNS) relapse was 5.4%. Conclusions. We have been able succe ssfully to perform a nationwide study. Our strategy to adapt the BFM protoc ol to our population of patients trial was effective in improving the EFS. The immunophenotype distribution is similar to that in other reported serie s. (C) 1999 Wiley-Liss, Inc.