| INSS Stage | Age | MYCN Status | Pathology Classification | DNA Ploidy | Risk Group Assignment |
| 1 | 0-21y | Any | Any | Any | Low |
| 2 | <365 d | Any | Any | - | Low |
| >365d-21y | Non-Amp | Any | - | Low | |
| >365d-21y | Amp | Favorable | - | Low | |
| >365d-21y | Amp | Unfavorable | - | High | |
| 3 | <365 d | Non-Amp | Any | Any | Intermediate |
| <365 d | Amp | Any | Any | High | |
| >365d-21y | Non-Amp | Favorable | - | Intermediate | |
| >365d-21y | Non-Amp | Unfavorable | - | High | |
| >365d-21y | Amp | Any | - | High | |
| 4 | <365 d | Non-Amp | Any | Any | Intermediate |
| <365 d | Amp | Any | Any | High | |
| >365d-21y | Any | Any | _ | High | |
| 4S | <365 d | Non-Amp | Favorable | > 1 | Low |
| <365 d | Non-Amp | Any | = 1 | Intermediate | |
| <365 d | Non-Amp | Unfavorable | Any | Intermediate | |
| <365 d | Amp | Any | Any | High |
