Table 1. Risk Groups for B-Precursor Acute Lymphoblastic Leukemiaa
| | Low Risk | Average Risk | High Risk | Very High Risk |
| NCI Risk (Age/WBC) | SR | SR | SR | SR | SR | HR (age <13 y) | SR | HR | HR (age ≥13 y) | SR or HR |
| Favorable Genetics | Yes | Yes | No | Yes | No | Yes or No | No | Yes or No | Yes or No | Yes or No |
| Unfavorable Characteristics | None | None | None | None | None | None | None | None | None | Yes |
| Day 8 PB MRD | <0.01% | ≥0.01% | <1% | Any Level | ≥1% | Any Level | Any Level | Any Level | Any Level | Any Level |
| Day 29 Marrow MRD | Low | Low | Low | High | Low | Low | High | High | <0.01% | Any Level |
| % of Patients (Estimated) | 15% | 36% | 25% | 24% |
| Anticipated 5-year EFS | >95% | 90%–95% | 88%–90% | <80% |
| EFS = event-free survival; HR = age and WBC count risk group is high risk; MRD = minimal residual disease; NCI = National Cancer Institute; PB = peripheral blood; SR = age/WBC count risk group is standard risk; WBC = white blood cell. |
| aFrom the Children's Oncology Group Classification of Newly Diagnosed ALL protocol. |
