Table 2.
Juvenile myelomonocytic leukemia high-risk features.
| EWOG/EBMT | EUROCORD/CIBMTR | UK | Europe | Japan | Conclusion | |
|---|---|---|---|---|---|---|
| Number studied (N) | 100 (1) | 110 (2) | 67 (42) | 44 (36) | 71 (34) | |
| HOST FACTORS | ||||||
| Age at diagnosis (years) | >4 | >1.4 | >2 | >2 | >2 | Older age is high-risk, best cut-off age has not been defined |
| Gender | Female | Not seen | Not reported | Not seen | Not seen | Evidence inconclusive |
| JMML-SPECIFIC FACTORSc | ||||||
| Type of mutation | Not seen | Not seen | Not reported | PTPN11 (trend) | PTPN11 | PTPN11 may be high-risk |
| Cytogenetic abnormality | Not seen | Monosomy 7 | Not monosomy 7 | Monosomy 7 | “Abnormal” | Monosomy 7 likely high-risk, evidence conflicting |
| HgbF at diagnosis | >40% | Not seen | Elevated | Not seen | Not seen | >40% may be high-risk |
| Platelet count at diagnosis | Not seen | Not seen | <40 × 109/L | Not seen | Not seen | Low platelets may be high-risk |
| BM blasts at HCT | >20% | Not seena | Not reported | Not seenb | Not reported | >20% blasts is probably high-risk |
| TREATMENT-RELATED FACTORS | ||||||
| Splenectomy | Not seen | Beneficial | Not reported | Not reported | Not reported | Debatable, benefit may be specific to UCBT |
| Pre-HCT AML-like chemo | Not seen | Beneficial | Not reported | Not reported | Not reported | Debatable, benefit may be specific to UCBT |
| HLA well-matched donor | Not seen | Beneficial | Not reported | Not seen | Not reported | Debatable, benefit may be specific to UCBT |
| Serotherapy | Beneficial | Not seen | Not reported | Not reported | Not reported | Debatable, benefit may be specific to non-UCBT |
aPatients with >20% blasts at HCT not included.
bAML-like gene-expression profile is highest-risk.
cDNA hypermethylation is also high-risk (44).