Evidence for the efficacy of immunotherapy in children with high-risk neuroblastoma.

Neuroblastoma is the most common extra-cranial malignancy of childhood, with the highest incidence in children younger than 4 years. The prognosis depends on many factors, such as age at diagnosis, stage of disease and molecular genetic subtype. More than 50% of children who present with the disease are deemed to have high-risk neuroblastoma. The standard therapy for children with high-risk neuroblastoma consists of intensive chemotherapy, surgery, radiotherapy, myeloablative consolidation with autologous haematopoietic stem cell rescue followed by the treatment of minimal residual disease with 13-cis-retinoic acid. Unfortunately, more than half of the patients relapse regardless of the treatment intensity. Combined therapy with monoclonal antibodies (anti-GD2), intravenous interleukin-2 (Il-2), intravenous granulocyte-macrophage colony-stimulating factor (GM-CSF) and oral 13-cis-retinoic acid have been proved to be effective in some randomised trials. A better understanding of the underlying immunological processes in therapy with anti-GD2 antibodies will allow its success to be evaluated more accurately and direct future endeavours. Nevertheless, the long-term benefit of this treatment approach needs to be established.