Cytogenetic classification for risk grouping in acute myeloid leukemia (AML).*†
| Cytogenetic Abnormality . | Frequen cy in Children . | Frequency in Adults . | Fusion Genes . | Genetic and Biologic Modifiers of Outcome . |
|---|---|---|---|---|
| Others: 20q, 21q, del (9q), t(9;22), abn 17p, complex karyotypes (≥ 3) | ||||
| *Adapted from References 1, 2, 11, 24. | ||||
| †It should be noted that this classification scheme is that used by the US Cooperative Groups.24 The MRC11 uses an altered classification scheme in which abn11q23, del(9), del(7q) without other abnormalities and complex abn ≥ 3 but ≤ 5 are considered “intermediate” risk, not “unfavorable” as shown in this table. Awareness of these differences in cytogenetic risk grouping is critical for comparison of outcome on clinical trials conducted by these groups. | ||||
| “Favorable” Cytogenetics | ||||
| t(8;21)(q22;q22) | 12% | 5-8% (< 55 yrs), Rare (> 55 yrs) | AML1/ETO | FLT3 ITD (9%) + del(9q), + Complex |
| Inv(16)(p13q22) | 12% | 10% (< 45 yrs), Rare (> 45 yrs) | CBFβ/MYH11 | FLT3 ITD (7%) |
| t(16;16)(p13;q22) | ||||
| t(15;17)(q21;q11) | 7% | 15% (< 45 years), Rare (> 45 years) | PML-RARα | FLT3 ITD (37%) |
| Variants: | ||||
| t(11;17)(q23;q11) | PLZF-RARα | |||
| t(5;17)(q32;q11) | NPM-RARα | |||
| t(11;17)(q13;q11) | NuMA-RARα | |||
| “Intermediate” Cytogenetics | ||||
| +8 | Rare | 10% | FLT3 ITD (28%) | |
| Normal karyotype | 10-15% | 15-20% | FLT3 ITD (34%) | |
| MLL ITD (10%) | ||||
| Others: Y, +6, All other karyotypes not considered favorable or unfavorable | FLT3 ITD (20-30%) | |||
| “Unfavorable” Cytogenetics | ||||
| Abn 11q23 | > 50% of infant AML cases 7% t(9;11) | 5-7% | MLL | FLT3 ITD (0%) |
| Common Variants: | ||||
| t(4;11)(q21;q23) | MLL/AF4 | |||
| t(9;11)(p22;q23) | MLL/AF9 | |||
| t(11;19)(q23;p13.1) | MLL/ELL | |||
| t(11;19)(q23;p13.3) | MLL/ENL | |||
| t(6;9)(p23;q34) | Rare | <1% | DEK/CAN | Inv(3)(q21q26), |
| t(3;3)(q21;q26) | 3% | 3-5% | Ribophorin/EVI1 | FLT3 ITD (17%) |
| –5/del(5q) | Rare | <10% (< 45 yrs) >10% (> 45 yrs) | MDR drug resistance FLT3 ITD (0%) | |
| –7/del(7q) | 10% | <10% (< 45 yrs) >10% (> 45 yrs) | MDR drug resistance FLT3 ITD (7%) | |
| Cytogenetic Abnormality . | Frequen cy in Children . | Frequency in Adults . | Fusion Genes . | Genetic and Biologic Modifiers of Outcome . |
|---|---|---|---|---|
| Others: 20q, 21q, del (9q), t(9;22), abn 17p, complex karyotypes (≥ 3) | ||||
| *Adapted from References 1, 2, 11, 24. | ||||
| †It should be noted that this classification scheme is that used by the US Cooperative Groups.24 The MRC11 uses an altered classification scheme in which abn11q23, del(9), del(7q) without other abnormalities and complex abn ≥ 3 but ≤ 5 are considered “intermediate” risk, not “unfavorable” as shown in this table. Awareness of these differences in cytogenetic risk grouping is critical for comparison of outcome on clinical trials conducted by these groups. | ||||
| “Favorable” Cytogenetics | ||||
| t(8;21)(q22;q22) | 12% | 5-8% (< 55 yrs), Rare (> 55 yrs) | AML1/ETO | FLT3 ITD (9%) + del(9q), + Complex |
| Inv(16)(p13q22) | 12% | 10% (< 45 yrs), Rare (> 45 yrs) | CBFβ/MYH11 | FLT3 ITD (7%) |
| t(16;16)(p13;q22) | ||||
| t(15;17)(q21;q11) | 7% | 15% (< 45 years), Rare (> 45 years) | PML-RARα | FLT3 ITD (37%) |
| Variants: | ||||
| t(11;17)(q23;q11) | PLZF-RARα | |||
| t(5;17)(q32;q11) | NPM-RARα | |||
| t(11;17)(q13;q11) | NuMA-RARα | |||
| “Intermediate” Cytogenetics | ||||
| +8 | Rare | 10% | FLT3 ITD (28%) | |
| Normal karyotype | 10-15% | 15-20% | FLT3 ITD (34%) | |
| MLL ITD (10%) | ||||
| Others: Y, +6, All other karyotypes not considered favorable or unfavorable | FLT3 ITD (20-30%) | |||
| “Unfavorable” Cytogenetics | ||||
| Abn 11q23 | > 50% of infant AML cases 7% t(9;11) | 5-7% | MLL | FLT3 ITD (0%) |
| Common Variants: | ||||
| t(4;11)(q21;q23) | MLL/AF4 | |||
| t(9;11)(p22;q23) | MLL/AF9 | |||
| t(11;19)(q23;p13.1) | MLL/ELL | |||
| t(11;19)(q23;p13.3) | MLL/ENL | |||
| t(6;9)(p23;q34) | Rare | <1% | DEK/CAN | Inv(3)(q21q26), |
| t(3;3)(q21;q26) | 3% | 3-5% | Ribophorin/EVI1 | FLT3 ITD (17%) |
| –5/del(5q) | Rare | <10% (< 45 yrs) >10% (> 45 yrs) | MDR drug resistance FLT3 ITD (0%) | |
| –7/del(7q) | 10% | <10% (< 45 yrs) >10% (> 45 yrs) | MDR drug resistance FLT3 ITD (7%) | |