Table 1.
Characteristics of patients in the German Cooperative Study Group for Childhood Acute Lymphoblastic Leukemia COALL-92/97 and the ALL-IX Dutch Childhood Oncology Group discovery cohort and in the St. Jude validation cohort*
| No. of patients |
|||
| Variable | COALL-DCOG (n = 177) | St. Jude (n = 95) | P value† |
| Age, y | .13 | ||
| 1–10 | 130 | 78 | |
| >10 | 47 | 17 | |
| Subtype‡ | .97 | ||
| B-lineage other | 47 | 22 | |
| BCR-ABL | 5 | 3 | |
| E2A-PBX1 | 8 | 5 | |
| MLL-AF4 | 3 | 1 | |
| TEL-AML1 | 44 | 22 | |
| Hyperdiploid | 43 | 28 | |
| T cell | 28 | 14 | |
| WBCs, No. × 109 per liter | .66 | ||
| <10 | 42 | 28 | |
| 10–49 | 67 | 36 | |
| 50–100 | 28 | 15 | |
| >100 | 39 | 16 | |
COALL-DCOG = German Cooperative Study Group for Childhood Acute Lymphoblastic Leukemia COALL-92/97 and the ALL-IX Dutch Childhood Oncology Group (the discovery cohort); St. Jude = validation cohort; WBCs = white blood cells.
Fisher exact test. All statistical tests were two-sided.
The BCR-ABL gene fusion is a translocation of parts of chromosomes 9 and 22, t(9;22), and involves the gene break point cluster region protein and Abelson murine leukemia viral (v-abl) oncogene homolog 1.The t(1;19) translocation creates E2A-PBX1 fusion gene and involves pre-B-cell leukemia homeobox 1 and E2A immunoglobulin enhancer-binding factor E12/E47. The t(4;11) translocation creates the MLL-AF4 fusion gene involving the mixed-lineage leukemia and the AF4–FMR2 family member 1 gene. The t(12;21) translocation creates the TEL-AML1 fusion gene, involving the ets variant gene 6 (TEL oncogene) and the runt-related transcription factor 1 (acute myeloid leukemia 1; aml1 oncogene). Hyperdiploid cells were identified by cytogenetics as having more than 51 chromosomes.