MYCN and neuroblastoma: Clinically, NB can be divided into low-risk (LR), intermediate-risk (IR) and high-risk (HR) types according to the Children's Oncology Group (COG) classification based on the demarcation of age at diagnosis, the International Neuroblastoma Staging System (INSS) stage, the tumor tissue MYCN status, the International Neuroblastoma Pathology Committee (INPC) classification and ploidy.