Table 1. Baseline Characteristics of Participants in a Study of the Effect of Postreinduction Consolidation With Blinatumomab vs Chemotherapy in Children, Adolescents, and Young Adults With First Relapse of B-Cell Acute Lymphoblastic Leukemia.
| Characteristic | No. (%) | |
|---|---|---|
| Blinatumomab (n = 105) | Chemotherapy (n = 103) | |
| Age at enrollment, y | ||
| Median (IQR) | 9 (6-16) | 9 (5-16) |
| 1-9 | 55 (52.4) | 55 (53.4) |
| 10-12 | 10 (9.5) | 11 (10.7) |
| 13-17 | 25 (23.8) | 19 (18.4) |
| 18-20 | 8 (7.6) | 10 (9.7) |
| 21-27a | 7 (6.7) | 8 (7.8) |
| Age at initial diagnosis, y | ||
| Median (IQR) | 6 (3-13) | 6 (3-13) |
| <1 | 7 (6.7) | 10 (9.7) |
| 1-9 | 56 (53.3) | 55 (53.4) |
| 10-12 | 16 (15.2) | 11 (10.7) |
| 13-17 | 24 (22.9) | 18 (17.5) |
| 18-26a | 2 (1.9) | 9 (8.7) |
| Sex | ||
| Female | 48 (45.7) | 49 (47.6) |
| Male | 57 (54.3) | 54 (52.4) |
| Race | n = 83 | n = 89 |
| American Indian or Alaska Native | 2 (2.4) | 0 |
| Asian | 4 (4.8) | 4 (4.5) |
| Black or African American | 7 (8.4) | 18 (20.2) |
| White | 69 (83.1) | 66 (74.2) |
| Multiple | 1 (1.2) | 1 (1.1) |
| Ethnicity | n = 97 | n = 98 |
| Hispanic or Latino | 36 (37.1) | 34 (34.7) |
| Not Hispanic or Latino | 61 (62.9) | 64 (65.3) |
| Site of relapse | ||
| Marrow (≥36 mo after diagnosis) | 36 (34.3) | 34 (33.0) |
| Marrow (18-36 mo after diagnosis) | 41 (39.0) | 41 (39.8) |
| MRD ≥0.1%, No.b | 19 | 19 |
| MRD <0.1%, No.b | 22 | 21 |
| MRD unknown, No.b | 0 | 1c |
| Marrow (<18 mo after diagnosis) | 18 (17.1) | 18 (17.5) |
| MRD ≥0.1%, No.b | 8 | 8 |
| MRD <0.1%, No.b | 9 | 10 |
| MRD unknown, No.b | 1d | 0 |
| Isolated extramedullary (<18 mo after diagnosis) | 10 (9.5) | 10 (9.7) |
| Risk group assignment after reinduction | ||
| High risk | 69 (65.7) | 69 (67.0) |
| Intermediate risk | 36 (34.3) | 34 (33.0) |
| Cytogenetic groupe | ||
| Favorable | 21 (23.3) | 16 (17.6) |
| ETV6-RUNX1, No. | 12 | 8 |
| Hyperdiploid with +4, +10, No. | 9 | 8 |
| Unfavorable | 7 (7.8) | 10 (11) |
| KMT2A-rearranged, No. | 7 | 9 |
| Hypodiploid, No. | 0 | 1 |
| Other | 62 (68.9) | 65 (71.4) |
| Unknown, No. | 15 | 12 |
Abbreviation: IQR, interquartile range.
Patients aged up to 30 years were eligible for inclusion; however, no patient enrolled was older than 26 years at initial diagnosis or 27 years at enrollment.
Minimal residual disease (MRD) is ascertained by assays of blood specimens that use polymerase chain reactions or flow cytometry to detect acute lymphoblastic leukemia cells; MRD is defined by the presence of at least 0.01% acute lymphoblastic leukemia cells in a posttreatment blood specimen and predicts the likelihood of relapse.
This patient’s MRD after reinduction was unsatisfactory. The patient was treated as stratum “high-risk patients (marrow ≥18 to <36 mo; MRD <0.1%)” for randomization.
This patient’s MRD after reinduction was indeterminate due to a strange immunophenotype. The patient was categorized in the high-risk group for randomization.
Reported by site using indicated categorical choices, which included the “unknown” category, based on cytogenetic results from original diagnosis. The indicated cytogenetic categories were of interest due to their known association with either favorable or unfavorable prognosis in the setting of upfront treatment.