Rapid-sequence tandem transplant for children with high-risk neuroblastoma

Background. The majority of patients with high risk neuroblastoma (NB) still relapse. Procedure. We designed a Phase II trial for children with advanced NB utilizing a program of induction chemotherapy followed by tandem high-dose chemoradiotherapy with stem cell rescue (HDC/SCR) in rapid sequence. Fifty-five patients were evaluable, ages 1-14 years, and 97 cycles of HDC/SCR have been completed to date. Pheresis was possible for every patient, despite their young age, with an average of 7.2 x 10⁶ CD34+ cells/kg available to support each HDC/SCR cycle. Results. Engraftment was rapid, with median time to neutrophil engraftment of 11 days. Five patients who completed the first HDC course did not complete the second and there were four toxic deaths. With a median follow-up of 24 months from diagnosis, 38 of 55 patients (3-year EFS 59%) remain event-free. A subset of the patients received stem cells purged by CD34 selection. The engraftment and EFS of these patients are similar to the overall group. Conclusion. This work demonstrates that a tandem transplant regimen for high-risk NB is a feasible treatment strategy in children and may improve disease-free survival. (C) 2000 Wiley-Liss, Inc.