Peripheral neuroblastic tumors: tumor biology and its implications for risk stratification

Peripheral neuroblastic tumor (pNT) is a pediatric tumor that originates from the sympathetic nervous system and is the most common extracranial solid malignancy found in children. It is characterized by its clinical and biological heterogeneity. Therefore, an International Neuroblastoma Risk Group (INRG) classification system was developed to create a standardized approach for pretreatment risk stratification. This system considers several factors, including the patient's age, tumor histology, the International Neuroblastoma Risk Group Staging System (INRGSS), DNA ploidy, the presence or absence of MYCN gene amplification in tumor cells, and segmental chromosomal aberrations, particularly the 11q aberration. In this review, we summarize the biological characteristics of peripheral neuroblastic tumors. We present their histopathological features, outline the different prognostic groups, discuss various molecular markers, and emphasize the importance of the risk stratification system in optimizing treatment.