Patients’ characteristics
| . | IKZF1 wild-type . | IKZF1-deleted . | . | ||
|---|---|---|---|---|---|
| . | (n = 65) . | (n = 126) . | . | ||
| . | N . | % . | N . | % . | P value . |
| Gender | |||||
| Male | 44 | 67.7 | 85 | 67.5 | .97 |
| Female | 21 | 32.3 | 41 | 32.5 | |
| Age (years) | |||||
| <10 | 43 | 66.2 | 71 | 56.4 | .19 |
| ≥10 | 22 | 33.8 | 55 | 43.6 | |
| White blood cell count (cells × 109/L)* | |||||
| <50 | 42 | 65.6 | 58 | 46.0 | .006 |
| 50-100 | 10 | 15.6 | 15 | 11.9 | |
| ≥100 | 12 | 18.8 | 53 | 42.1 | |
| Early clinical response† | |||||
| Yes | 38 | 63.3 | 81 | 66.4 | .68 |
| No | 22 | 36.7 | 41 | 33.6 | |
| IKZF1 status | |||||
| Wild-type | 65 | 100.0 | NA | NA | |
| Haploinsufficient | NA | NA | 46 | 36.5 | |
| Dominant negative | NA | NA | 66 | 52.4 | |
| Miscellaneous | NA | NA | 14 | 11.1 | |
| . | IKZF1 wild-type . | IKZF1-deleted . | . | ||
|---|---|---|---|---|---|
| . | (n = 65) . | (n = 126) . | . | ||
| . | N . | % . | N . | % . | P value . |
| Gender | |||||
| Male | 44 | 67.7 | 85 | 67.5 | .97 |
| Female | 21 | 32.3 | 41 | 32.5 | |
| Age (years) | |||||
| <10 | 43 | 66.2 | 71 | 56.4 | .19 |
| ≥10 | 22 | 33.8 | 55 | 43.6 | |
| White blood cell count (cells × 109/L)* | |||||
| <50 | 42 | 65.6 | 58 | 46.0 | .006 |
| 50-100 | 10 | 15.6 | 15 | 11.9 | |
| ≥100 | 12 | 18.8 | 53 | 42.1 | |
| Early clinical response† | |||||
| Yes | 38 | 63.3 | 81 | 66.4 | .68 |
| No | 22 | 36.7 | 41 | 33.6 | |
| IKZF1 status | |||||
| Wild-type | 65 | 100.0 | NA | NA | |
| Haploinsufficient | NA | NA | 46 | 36.5 | |
| Dominant negative | NA | NA | 66 | 52.4 | |
| Miscellaneous | NA | NA | 14 | 11.1 | |
NA, not applicable.
White blood cell count was unknown in 1 patient (EsPhALL cohort).
Early clinical response was defined as <1000 cells/μL in peripheral blood after 7 days of treatment with prednisone and a single intrathecal dose of methotrexate, or ≤5% leukemic blast cells in the bone marrow at day 21 (depending on national induction protocols). Early clinical response was unknown for 5 wild-type and 4 IKZF1-deleted patients (all from the pre-TKI cohort).