Table 1.

Established prognostic variables accepted by the North American Children’s Oncology Group (COG) and the SIOP (International Society of Pediatric Oncology) Group.

Risk classification	Characteristics
Standard-risk tumor	≥3 years of age without evidence of metastatic spread and having ≤1.5 cm2 (maximum cross- sectional area) of residual disease after surgery
High-risk tumor	≥3 years of age with evidence of CSF spread (M1–M3) and/or those with less complete resection (≥1.5 cm2) or <3 years of age at diagnosis