TABLE 3.

Children’s Oncology Group risk stratification for children with neuroblastoma

Risk Stratification	INSS Stage	Age	Biology
Low
Group 1
	1	Any	Any
	2A/2B (>50% resected)	Any	MYCN-NA, any histology/ploidy
	4S	<365 days	MYCN-NA, FH, DI>1
Intermediate
Group 2
	2A/2B (<50% resected or Bx only)	0–12 years	MYCN-NA, any histology/ploidy*
	3	<365 days	MYCN-NA, FH, DI>1*
	3	≥365 days - 12 years	MYCN-NA, FH*
	4S (symptomatic)	<365 days	MYCN-NA, FH, DI>1*
Group 3
	3	<365 days	MYCN-NA, either UH or DI=1*
	4	<365 days	MYCN-NA, FH, DI>1*
	4S	<365 days	MYCN-NA, either UH or DI=1*; or unknown biology
Group 4
	4	<365 days	MYCN-NA, either DI=1 or UH
	3	365 -<547 days	MYCN-NA, UH, any ploidy
	4	365 -<547 days	MYCN-NA, FH, DI>1
High
	2A/2B, 3, 4, 4S	Any	MYCN-amplified, any histology/ploidy
	3	≥ 547 days	MYCN-NA, UH, any ploidy
	4	365 - >547 days	MYCN-NA, UH or DI=1
	4	> 547 days	Any

^*If tumor contains chromosomal 1p LOH or unb11qLOH, or if data are missing, treatment assignment is upgraded to next Group.

MYCN-NA: MYCN not amplified, FH: favorable histology, UH: unfavorable histology, DI: DNA index