Allogeneic bone marrow transplant in pediatric patients with high-risk hematopoietic malignancies early in the course of their disease

Abstract

Purpose: The purpose of this study was to investigate the role of bone marrow transplant (BMT) early in the course of disease for pediatric patients with high-risk leukemia using a preparatory regimen of fractionated total body irradiation (FTBI) and etoposide (VP-16).

Patients and methods: Those studied were 33 patients aged < or =18 years with either acute leukemia in first complete remission (CR) (n = 29) or chronic myelogenous leukemia (CML) in first chronic phase (n = 4) who received 1,320 cGy FTBI followed by high-dose VP-16 (60 mg/kg) as a preparatory regimen for BMT from matched sibling donors. Patients with acute leukemia included 18 with acute nonlymphocytic leukemia (ANLL), one with biphenotypic acute leukemia (BAL), and 10 with selected "high-risk" acute lymphocytic leukemia (ALL). Patients with ALL were selected for a high risk for recurrence: those who failed standard remission induction chemotherapy, had a t(9;22) or t(4;11) chromosomal translocation, or had certain clinical high-risk features.

Results: At the time of analysis, 28 patients are alive, all of them in continued complete remission for 1.1-7.8 years (median, 5.3 years; mean, 4.9 years). The Kaplan-Meier projected event-free survival (EFS) is 84.5% at 7 years, and the actuarial recurrence hazard is 6.5%. All surviving patients have a performance status of >80%.

Conclusion: This result of early BMT in a two-institution study of pediatric patients with hematopoietic malignancies suggests that (a) matched sibling allogeneic BMT after conditioning with FTBI and high-dose VP-16 is an excellent treatment for pediatric patients with high-risk leukemia, and (b) children may have a better prognosis than adults treated with allogeneic BMT. Larger multiinstitutional cooperative trials for pediatric patients are needed to confirm this result.