Intensive chemotherapy for systemic anaplastic large cell lymphoma in children and adolescents: Final results of children's cancer group study 5941

Background. Anaplastic large cell lymphoma (ALCL) is characterized by advanced disease at presentation (70-80% of pediatric cases) and accounts for 10-15% of all childhood lymphomas. Treatment strategies for pediatric ALCL vary from short pulse B-NHL chemotherapy to prolonged leukemia like therapy. The optimal treatment strategy is unknown. Methods. CCG-5941 used a compressed aggressive multiagent T-cell lineage chemotherapy regimen consisting of a 3-week induction therapy (vincristine, prednisone, cyclophosphamide, daunomycin, asparaginase) followed by a 3-week consolidation period (vincristine, prednisone, etoposide, 6-thioguanine, cytarabine, asparaginase, methotrexate) followed by six courses of maintenance chemotherapy at 7-week intervals (cyclophosphamide, 6-thioguanine, vincristine, predni- sone, doxorubicin, asparaginase, methotrexate etoposide, cytara- bine). Total therapy was 48 weeks. Results. Eighty-six children (male 56%, female 44%) with non-localized ALCL (CD30+) were treated. The majority of tumors were positive for ALK (90%) and of T lineage (83%). Extranodal disease was common (mediastinum 35%, skin 15%, lung 14%, bone 12%, bone marrow 13%, liver 6%, and other viscera 17%). Grade 4 neutropenia occurred in 82% of patients. The 5-year EFS was 68% (95% CI of 57-78%) and the 5-year OS was 80% (95% CI of 69-87%). There were 21 relapses and 4 toxic deaths as first events. Relapse occurred early with 17 (81%) relapses occurring within 2 years of diagnosis and 12 (57%) while receiving therapy. Univariate analysis for risk factors only identified bone marrow involvement predicting lower EFS (P = 0.03). Conclusions. CCG-5941 demonstrated efficacy similar to previously reported regimens but with significant hematologic toxicity.