Purpose or Case Report: Because of issues with the reliability of the previous staging system, the International Neuroblastoma Risk Group Staging System (INRG-SS) was created in 2009. Like with the introduction of any new tool, there has been some resistance to the embracing of the INRG-SS staging system by radiologists. This educational poster offers a practical approach to learning and utilizing the INRG system, emphasizing use of the descriptive terms which determine the presence or absence of imaging defined risk factors (IDRFs).
Methods & Materials: The radiology systems were word searched for imaging examples of neuroblastoma from various imaging modalities. Illustrative cases were selected that demonstrated the descriptive terms that determine whether an IDRF is present or absent.
Results: Illustrative cases demonstrate the potential relationships between the neuroblastoma and vital structures. The descriptive terms that define whether an IDRF are present or absent, determining whether a lesion is L1 or L2 are emphasized:

Arteries: separation, contact, or encasement
Veins: compression, flattening
Airway: compression
Spinal Canal: non-invasion, invasion
Non-Tubular Vital Structures: Infiltration
Conclusions: Neuroblastoma imaging at time of diagnosis plays a critical role in patient’s treatment planning strategies. These educational poster is intended to present a practical approach to using the INRG-SS classification system. This approach emphasizes the definitions of descriptive terms that determine whether an IDRF is present or absent.