International Neuroblastoma Risk Group Staging System
| Stage | Definition |
|---|---|
| L1 | Localized tumor without image-defined risk factors for surgery |
| L2 | Locoregional tumor with image-defined risk factors |
| M | Metastatic |
| MS | Metastatic in infant < 18 mo old with metastases limited to liver, skin, and bone marrow |