HHE Haematology supplement 2018 - Page 7

hAEmatology and oncology Anti-GD2 mAbs for the treatment of high-risk neuroblastoma Anti-GD2 monoclonal antibodies have recently been approved by the EU and US regulatory agencies and are currently the only formally approved drugs for the treatment of high-risk neuroblastoma Jaume Mora MD PhD Department of Pediatric Oncology and Hematology, Hospital Sant Joan de Déu, Barcelona, Spain Neuroblastoma is the most common extracranial paediatric solid tumour in Europe. Close to 40% of all neuroblastoma patients are classified as high risk (HR) because the chance of relapse or death within two years of diagnosis is close to 50%. Immunotherapy with anti-GD2 monoclonal antibodies (mAbs) is now considered the only important therapeutic advance in the treatment of HR neuroblastoma in the last decade. The availability and sustainability of these antibodies in the market as well as the cost they represent within an already expensive treatment for neuroblastoma patients are relevant issues affecting parents, physicians, regulatory bodies and insurers. Neuroblastic tumours Neuroblastic tumours (NBTs) derive from 7 HHE 2018 | hospitalhealthcare.com primordial neural crest cells and are the most common extracranial solid childhood tumours in Europe. Under normal conditions, neural crest cells delaminate and migrate from the dorsal neural tube, and those neuroblastic precursor cells differentiate upon reaching their final embryonic location into tissues and organs that will constitute the sympathetic nervous system. In vitro and in vivo studies have shown that NBTs originate from a block in the process of normal differentiation of these precursor cells. 1,2 Histologically, NBTs are classified in three categories: neuroblastoma (NB); ganglioneuroblastoma (GNB); and ganglioneuroma (GN). By definition, Schwannian stroma should comprise less than 50% of the tumour tissue to be NB. Undifferentiated NB is composed of neuroblastic cells without