Allogeneic stem cell transplantation for neuroblastoma.

Neuroblastoma (NB) is the most common extracranial solid tumor in children. Although the prognosis of lowand intermediate-risk NB with conventional treatment modalities is excellent, the prognosis of high-risk NB with conventional treatment alone is very poor. The current standard treatment for high-risk NB consists of induction treatment (conventional chemotherapy and surgery with or without local radiotherapy), high-dose chemotherapy and autologous stem cell transplantation (HDCT/autoSCT) as a consolidation treatment, and 13-cis-retinoid acid to reduce relapse from minimal residual disease. However, the event-free survival rates are only 30-40%, which is unsatisfactory. For this reason, a few clinical trials of tandem HDCT/autoSCT, high-dose 131I-meta-iodobenzylguanidine (MIBG) treatment incorporated into HDCT/autoSCT, and anti-GD2 treatment after HDCT/autoSCT, are currently underway to improve the survival of high-risk NB patients. Furthermore, because about half of high-risk NB patients still die from treatment failure, allogeneic SCT (alloSCT) is being investigated as a potential curative option.