Anaplastic large-cell lymphoma (ALCL) accounts for approximately 10% of pediatric non-Hodgkin lymphoma (NHL). Previous experience from NHL-Berlin-Frankfurt-Münster (BFM) trials indicated that the short-pulse B-NHL-type treatment strategy may also be efficacious for ALCL. The purpose of this study was to test the efficacy of this protocol for treatment of childhood ALCL in a large prospective multicenter trial and to define risk factors. From April 1990 to March 1995, 89 patients younger than 18 years of age with newly diagnosed ALCL were enrolled in trial NHL-BFM 90. Immunophenotype was T-cell in 40 patients, B-cell in 5, null in 31, and not determined in 13. Stages were as follows: I, n = 8; II, n = 20; III, n = 55; IV, n = 6. Extranodal manifestations were as follows: mediastinum, n = 28; lung, n = 13; skin, n = 16; soft tissue, n = 13; bone, n = 14; central nervous system, n = 1; bone marrow, n = 5. After a cytoreductive prephase, treatment was stratified into 3 branches: patients in K1 (stage I and II resected) received three 5-day courses (methotrexate [MTX] 0.5 g/m(2), dexamethasone, oxazaphorins, etoposide, cytarabine, doxorubicin, and intrathecal therapy); patients in K2 (stage II nonresected and stage III) received 6 courses; patients in K3 (stage IV or multifocal bone disease) received 6 intensified courses including MTX 5 g/m(2), high-dose cytarabine/etoposide. The Kaplan-Meier estimate for a 5-year event-free survival was 76% +/- 5% (median follow-up, 5.6 years) for all patients and 100%, 73% +/- 6%, and 79% +/- 11% for K1, K2, and K3, respectively. Events were as follows: progression during therapy, n = 2; progression or relapse after therapy, n = 20; second malignancy, n = 1. It was concluded that short-pulse chemotherapy, stratified according to stage, is effective treatment for pediatric ALCL. B symptoms were associated with increased risk of failure. (Blood. 2001;97:3699-3706)