Synopsis

Neuroblastoma is the most common extracranial soft tissue malignancy in children. In 2004, the International Neuroblastoma Risk Group (INRG) published a new staging system designed to standardize the presurgical staging of neuroblastoma. The INRG staging system developed a series of 20 different image-defined risk factors (IDRF) that confer additional surgical risk and upstage a patient from L1 to L2 disease. Radiologists should be familiar with the different IDRFs and the standard definitions used assess patients with neuroblastoma.