Table. 2.

Table. 2.

International Neuroblastoma Risk Group (INRG) consensus pretreatment classification schema [4]

INRG Stage Age (month) Histologic category Grade of tumor differentiation MYCN 11q Aberration Ploidy Pretreatment risk group
L1/L2 GN maturing; GNB intermixed A Very low
L1 Any, except GN maturing or GNB intermixed NA B Very low
Amp K High
L2 <18 Any, except GN maturing or GNB intermixed NA No D Low
Yes G Intermediate
≥18 GNB nodular; neuroblastoma Differentiating NA No E Low
Yes H Intermediate
Poorly differentiated or undifferentiated NA
Amp N High
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

Pretreatment risk group H has two entries. 12 months=365 days; 18 months=547 days; blank field=“any”; diploid (DNA index ≤1.0); hyperdiploid (DNA index >1.0 and includes near-triploid and near-tetraploid tumors); very low risk (5-year EFS >85%); low risk (5-year EFS >75% to ≤85%); intermediate risk (5-year EFS ≥50% to ≤75%); high risk (5-year EFS <50%). GN, ganglioneuroma; GNB, ganglioneuroblastoma; Amp, amplified; NA, not amplified; L1, localized tumor confined to one body compartment and with absence of image-defined risk factors (IDRFs); L2, locoregional tumor with presence of one or more IDRFs; M, distant metastatic disease (except stage MS); MS, metastatic disease confined to skin, liver and/or bone marrow in children <18 months of age; EFS, event-free survival. Note: This table is the same as Fig. 2 in Cohn SL et al. (2008) The International Neuroblastoma Risk Group (INRG) Classification System: An INRG Task Force Report J Clin Oncol (2008) 27:289-297 [4]

Clin Pediatr Hematol Oncol 2020;27:73-86
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