[Treatment results in children with the standard risk acute lymphoblastic leukemia treated with high dose of methotrexate (5.0 g/m2). 11 years of the Polish Pediatric Leukemia/Lymphoma Study Group experience]. / Wyniki leczenia ostrej bialaczki limfoblastycznej grupy standardowego ryzyka (ALL-SR) u dzieci z zastosowaniem wysokich dawek metotreksatu (HD-MTX 5,0 g/m2)--11 lat doswiadczen Polskiej Pediatrycznej Grupy ds. Leczenia Bialaczek i Chloniaków.

Since 01.07.1993 to 30.09.2004, 675 children with ALL-SR were diagnosed and treated according to the modified ALL-BFM 90 protocol. Subject to statistical analysis (Kaplan-Meier method) were thus 197 children with ALL-SR treated with HD-MTX in a dose 5.0g/ m2. Among them, 21 patients failed to respond to therapy: 2 (1.0%) early deaths, 2 (1.0%) deaths during I complete remission, 16 (8.2%) relapses, 1 (0.5%) second neoplasm. Relapses occured: 12 (6.2%) in bone marrow, 2 (1.0%) in central nervous system, 1 (0.5%) in testicle and in 1 (0.5%) child combined relapse was observed. Probability rates for 11-year event free survival (EFS) was 0.80 (0.03). Application of high dose of methotrexate is safety and effective in prevention of relapses, especially meningeal and testicular involvement.