Comparison of treatment regimens for pediatric lymphoblastic non-Hodgkin's lymphoma: a Childrens Cancer Group study.

PURPOSE: Patients with lymphoblastic non-Hodgkin's lymphoma (LB NHL) were randomized to treatment with either modified LSA2L2 or ADCOMP, which added daunorubicin (DAUN) and asparaginase (L-ASP) to the methotrexate (MTX), cyclophosphamide (CYT), vincristine (VCR), and prednisone (PRED) (COMP) regimen, in a clinical trial to determine the relative effectiveness and toxicity of the two regimens.

PATIENTS AND METHODS: Patients with LB NHL were eligible for this randomized study if they were less than 22 years of age at diagnosis and had < or = 25% blasts in the bone marrow. Of 307 patients registered, 281 were fully eligible and assessable. Patients were stratified by extent of disease at diagnosis.

RESULTS: The 5-year event-free survival (EFS) rate for patients with localized disease was 84%, and for patients with disseminated disease, 67%. There were four relapses in 28 patients with localized disease. Two hundred six patients had mediastinal primary tumors and despite local radiation, 34 of 63 failures in these patients involved the primary tumor site with or without other involvement. After adjusting for extent of disease at diagnosis, the regimens did not differ significantly with respect to risk for adverse events. The acute toxicity was primarily neutropenia and thrombocytopenia, with greater initial toxicity in patients on the LSA2L2 regimen. Three patients developed acute myelogenous leukemia.

CONCLUSION: Long-term EFS in children with LB NHL can be achieved in the majority of patients. Disease progression, which includes recurrence at the primary tumor site, is a major cause of treatment failure in patients with mediastinal presentations. Addition of DAUN and L-ASP to the COMP regimen does not produce a more effective treatment than LSA2L2.