Table 3.
International Neuroblastoma Treatment Risk Groups
| INRG Stage | Age (months) | Histological classification | Grade of tumor differentiation | MYCN | 11q Aberration | Ploidy | Pretreatment risk group |
|---|---|---|---|---|---|---|---|
| L1/L2 | Any | GN maturing | A Very Low | ||||
| GNB intermixed | |||||||
| L1 | Any | Any except | NA | B Very Low | |||
| GN maturing or | Amp | K High | |||||
| GNB intermixed | |||||||
| L2 | <18 | Any except | NA | No | D Low | ||
| GN maturing or | Yes | G | |||||
| GNB intermixed | Intermediate | ||||||
| ≥18 | GNB nodular; | Differentiating | NA | No | E Low | ||
| neuroblastoma | Poorly differentiating or undifferentiating | NA | Yes | ||||
| H Intermediate | |||||||
| M | <18 | NA | Hyperdiploid | F Low | |||
| <12 | NA | Diploid | I Intermediate | ||||
| 12 to <18 | NA | Diploid | J Intermediate | ||||
| <18 | Amp | O High | |||||
| ≥18 | P High | ||||||
| MS | <18 | NA | No | C Very Low | |||
| Yes | Q High | ||||||
| Amp | R High |