Patient characteristics
| . | CCG, 16 to 20 y, n = 197 . | CALGB, 16 to 20 y, n = 124 . | P . |
|---|---|---|---|
| Median age, y | 16 | 19 | < .001 |
| Sex, no. (%) male | 129 (65) | 87 (70) | .45 |
| Ethnic distribution, no. (%) | .89 | ||
| White | 141 (72) | 90 (73) | |
| Hispanic | 32 (16) | 19 (15) | |
| African-American | 13 (7) | 10 (8) | |
| Other | 11 (5) | 5 (4) | |
| Immunophenotype, no. (%), evaluable* | 143 | 92 | |
| Precursor-T | 23 (16) | 23 (25) | .56 |
| Precursor-B | 93 (65) | 64 (70) | .13 |
| Other† | 27 (19) | 5 (5) | .006 |
| Cytogenetics, no. (%), evaluable* | 67 | 81 | |
| t(9;22) | 2 (3) | 5 (6) | .60 |
| t(4;11) | 2 (3) | 2 (2) | .75 |
| Initial WBCs more than 50 × 109/L, no. (%) | 47 (24) | 26 (21) | .64 |
| . | CCG, 16 to 20 y, n = 197 . | CALGB, 16 to 20 y, n = 124 . | P . |
|---|---|---|---|
| Median age, y | 16 | 19 | < .001 |
| Sex, no. (%) male | 129 (65) | 87 (70) | .45 |
| Ethnic distribution, no. (%) | .89 | ||
| White | 141 (72) | 90 (73) | |
| Hispanic | 32 (16) | 19 (15) | |
| African-American | 13 (7) | 10 (8) | |
| Other | 11 (5) | 5 (4) | |
| Immunophenotype, no. (%), evaluable* | 143 | 92 | |
| Precursor-T | 23 (16) | 23 (25) | .56 |
| Precursor-B | 93 (65) | 64 (70) | .13 |
| Other† | 27 (19) | 5 (5) | .006 |
| Cytogenetics, no. (%), evaluable* | 67 | 81 | |
| t(9;22) | 2 (3) | 5 (6) | .60 |
| t(4;11) | 2 (3) | 2 (2) | .75 |
| Initial WBCs more than 50 × 109/L, no. (%) | 47 (24) | 26 (21) | .64 |
WBC indicates white blood cell.
Patients were reviewed and confirmed by central cooperative group pathology and cytogenetic committees.
Different criteria were used by CCG and CALGB to characterize the immunophenotype and may account for the differences in numbers of patients in the ″other″ category. For CCG, the ″other″ category includes patients with coexpression of both B and T markers on lymphoblasts (14 patients) and 13 patients where the immunophenotype could not be fully resolved. For CALGB, only patients with coexpression of B and T markers were included in the ″other″ category.