Purpose: Relapse from stage 4 neuroblastoma usually carries a poor prognosis. A retrospective study using the European Bone Marrow Transplant (EBMT) Solid Tumor Registry was undertaken to define the role of megatherapy (MGT) in relapsed patients.
Patients and methods: After relapse, 33 boys and 15 girls with previous stage 4 neuroblastoma received intensification by MGT followed by either autologous (n = 42) or allogeneic (n = 6) bone marrow rescue in 11 European institutions. The median age at diagnosis was 47 months (range, 14 to 134) and the median interval from diagnosis to relapse was 16 months (range, 4 to 94). Thirty patients had received only conventional-dose primary treatments (group A), whereas 18 patients had previously received intensification with MGT (group B). The median follow-up time of the total group is 95 months (range, 25 to 185).
Results: The actuarial overall survival rate at 2 years after MGT for relapse is 27% for group A and 0% for group B (P = .02). Three adverse, independent prognostic factors were confirmed by multivariate analysis using the Cox proportional hazards regression model: an interval of less than 12 months between diagnosis and relapse (P < .0001), nonresponding or untreated relapse (P = .0002), and previous MGT during primary treatments (P = .055). None of the other variables analyzed, such as sex, age, bone or bone marrow involvement at diagnosis or at relapse, and type of MGT at relapse, influenced outcome in this patient cohort.
Conclusion: Responding patients who relapse more than 12 months from diagnosis who had not received previous MGT appear to benefit from consolidation MGT. Relapse patients who do not fulfill these criteria gain no advantage from this cost-intensive procedure and should be treated differently.