Long-term Results Of the Pediatric Oncology Group Studies For Childhood Acute Lymphoblastic Leukemia 1984-2001: A Report From The Children’s Oncology Group

From 1984-2001, the Pediatric Oncology Group (POG) conducted 12 acute lymphoblastic leukemia (ALL) studies. 10-year event free survival (EFS) for patients >12 months of age with B-precursor ALL on Acute Leukemia in Children 14, 15, and 16 series were 66.7 ± 1.2%, 68.1 ± 1.4% and 73.2 ± 2.1%, respectively. Intermediate dose methotrexate (ID MTX; 1 g/m(2)) improved outcomes for standard risk patients (10-year EFS 77.5 ± 2.7% vs. 66.3 ± 3.1% for oral MTX). Neither MTX intensification (2.5 g/m2) nor addition of cytosine arabinoside/daunomycin/teniposide improved outcomes for higher risk patients. Intermediate dose mercaptopurine (1 g/m(2)) failed to improve outcomes for either group. 10-year EFS for patients with T-cell ALL, POG 8704 and 9404, were 49.1 ± 3.1% and 72.2 ± 4.7%, respectively. Intensive asparaginase (10-year EFS 61.8% vs 42.7%) and high dose MTX (5 g/m(2)) (10-year EFS 78.0% vs. 65.8%) improved outcomes. There was a non-significant improvement in EFS for infants (10-year EFS 17.7 ± 7.2% to 31.9 ± 8.3%). Prognostic indicators for B-precursor ALL were age and WBC at diagnosis, gender, central nervous system disease, DNA index, and cytogenetic abnormalities. Only gender was prognostic in T-cell ALL. In infants, WBC and MLL translocation were linked to inferior outcome.