Journal of Pediatric Hematology/Oncology 2014-07-01

Dose intensification of methotrexate and cytarabine during intensified continuation chemotherapy for high-risk B-precursor acute lymphoblastic leukemia: POG 9406: a report from the Children's Oncology Group.

Richard L Tower, Tamekia L Jones, Bruce M Camitta, Barbara L Asselin, Beverly A Bell, Allen Chauvenet, Meenakshi Devidas, Edward C Halperin, Jeanette Pullen, Jonathan J Shuster, Naomi Winick, Joanne Kurtzberg

Index: J. Pediatr. Hematol. Oncol. 36(5) , 353-61, (2014)

Full Text: HTML

Abstract

To determine the efficacy and toxicity of higher dose versus standard dose intravenous methotrexate (MTX) and pulses of high-dose cytosine arabinoside with asparaginase versus standard dose cytosine arabinoside and teniposide during intensified continuation therapy for higher risk pediatric B-precursor acute lymphoblastic leukemia (ALL).From 1994 to 1999, the Pediatric Oncology Group conducted a randomized phase III clinical trial in higher risk pediatric B-precursor ALL. A total of 784 patients were randomized in a 2×2 factorial design to receive MTX 1 g/m versus 2.5 g/m and to cytosine arabinoside/teniposide versus high-dose cytosine arabinoside/asparaginase during intensified continuation therapy.Patients receiving standard dose MTX had a 5-year disease-free survival (DFS) of 71.8±2.4%; patients receiving higher dose MTX had a 5-year DFS of 71.7±2.4% (P=0.55). Outcomes on cytosine arabinoside/teniposide (DFS of 70.4±2.4) were similar to higher dose cytosine arabinoside/asparaginase (DFS of 73.1±2.3%) (P=0.41). Overall survival rates were not different between MTX doses or cytosine arabinoside/teniposide versus cytosine arabinoside/asparaginase.Increasing MTX dosing to 2.5 g/m did not improve outcomes in higher risk pediatric B-precursor ALL. Giving high-dose cytarabine and asparaginase pulses instead of standard dose cytarabine and teniposide produced nonsignificant differences in outcomes, allowing for teniposide to be removed from ALL therapy.