Division of Hematology and Oncology, Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Korea
Copyright © 2021 by the Korean Cancer Association
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- Low risk (all of the following criteria): age ≥ 1 and < 10 years old, initial white blood cell (WBC) count < 50×109/L, trisomies of 4, 10 and 17 or ETV6-RUNX1(+)
- Standard risk: as for low risk, except for lack of trisomies of 4, 10 and 17 or ETV6-RUNX1
- High risk (any one of the following criteria, irrespective of low risk cytogenetic features): age ≥ 10 and < 15 years old, initial WBC count ≥ 50×109/L and < 100×109/L, initial CNS or testicular involvement, poor prephase steroid response, E2A-PBX1(+), KMT2A rearrangement(+), minimal residual disease (MRD)(+) at end of remission induction (as measured by reverse transcription polymerase chain reaction [RT-PCR] or real-time quantitative [RQ-PCR] for patients with recurrent genetic abnormalities)
- Very high risk (any one of the following, irrespective of low risk cytogenetic features): age ≥ 15 years old, initial WBC count ≥ 100×109/L, Philadelphia chromosome-positive (Ph(+)) ALL, infant ALL, hypodiploidy (≤ 44 chromosomes), induction failure
- Four drug remission induction for all patients (vincristine, steroid, l-asparaginase, one dose of daunorubicin on day 1), preceded by 1 week of prephase steroid therapy (S1 Table).
- Intensification therapy based on patient risk, with low and standard risk patients receiving one phase of intensification, while high and very high risk patients received two phases of treatment (S2–S5 Tables).
- Maintenance therapy of 96 weeks for all patients regardless of sex. Treatment included pulses of vincristine and steroid every 4 weeks, as well as daily 6-mercaptopurine and weekly methotrexate (MTX). Of note, patients received high dose MTX (3 g/m2) and intrathecal MTX every 12 weeks during maintenance therapy (S6 Table).
- Omission of cranial irradiation in all patients. Treatment of CNS3 consisted of multiple triple intrathecal infusions (methotrexate, cytarabine, hydrocortisone) during remission induction, and use of dexamethasone in all phases of steroid treatment.
- Allogeneic hematopoietic cell transplantation (HCT) in first CR for patients with Ph(+) ALL, hypodiploidy, and induction failure. Since September 2011, infant ALL with KMT2A rearrangement was also included as an indication for allogeneic HCT in first CR.
- For Ph(+) ALL, imatinib was given concurrent with chemotherapy from consolidation up till HCT, as reported previously [14]. Imatinib was not given after HCT, unless the patient showed an increase in RQ-PCR value for BCR-ABL1.
Ethical Statement
The study received institutional review board (IRB) approval (number KC19RESI0504). As the study was retrospective, the need for informed consent from the patients was waived by the IRB.
Author Contributions
Conceived and designed the analysis: Lee JW, Kim S, Jang PS, Chung NG, Cho B.
Collected the data: Lee JW.
Performed the analysis: Lee JW.
Wrote the paper: Lee JW, Kim S, Jang PS, Chung NG, Cho B.
Conflicts of Interest
Conflicts of interest relevant to this article was not reported.
Characteristic | No. (%) (n=405) |
---|---|
Sex | |
Male/Female | 243 (60.0)/162 (40.0) |
Age at diagnosis, median (range, yr) | 5.6 (0.2–17.1) |
< 1 | 21 (5.2) |
1 to < 10 | 274 (67.7) |
≥ 10 | 110 (27.2) |
Initial WBC count at diagnosis, median (range, ×109/L) | 12.6 (0.9–896.1) |
< 50 | 309 (76.3) |
≥ 50 and < 100 | 40 (9.9) |
≥ 100 | 56 (13.8) |
Initial CNS involvementa) | |
Yes/No | 6 (1.5)/398 (98.3) |
NCI risk group | |
Standard/High | 228 (56.3)/177 (43.7) |
Prephase steroid responseb) | |
Good/Poor | 370 (91.4)/35 (8.6) |
Steroid used during treatment | |
Dexamethasone/Prednisolone | 146 (36.0)/259 (64.0) |
CR after remission induction | |
Yes/No | 392 (96.8)/13 (3.2) |
Risk group | |
Low/Standard | 94 (23.2)/80 (19.8) |
High/Very high | 114 (28.1)/117 (28.9) |
CNS, central nervous system; CR, complete remission; NCI, National Cancer Institute; WBC, white blood cell.
a) CNS involvement defined as CNS3 (≥ 5/μL WBCs and cytospin positive for blasts). One patient without initial CNS study,
b) A good response to 1 week of prephase steroid treatment defined as peripheral blast count < 1.0×109/L.
No. (%) (n=403)a) | |
---|---|
ETV6-RUNX1 | 93 (23.1) |
E2A-PBX1 | 31 (7.7) |
BCR-ABL1 | 31 (7.7) |
KMT2A rearrangement | 23 (5.7) |
High hyperdiploidyb) | 91 (22.6) |
Hypodiploidyc) | 2 (0.5) |
Normal karyotype | 50 (12.4) |
Others | 82 (20.3) |
Characteristic | No. (%) (n=405) |
---|---|
Sex | |
Male/Female | 243 (60.0)/162 (40.0) |
Age at diagnosis, median (range, yr) | 5.6 (0.2–17.1) |
< 1 | 21 (5.2) |
1 to < 10 | 274 (67.7) |
≥ 10 | 110 (27.2) |
Initial WBC count at diagnosis, median (range, ×109/L) | 12.6 (0.9–896.1) |
< 50 | 309 (76.3) |
≥ 50 and < 100 | 40 (9.9) |
≥ 100 | 56 (13.8) |
Initial CNS involvement | |
Yes/No | 6 (1.5)/398 (98.3) |
NCI risk group | |
Standard/High | 228 (56.3)/177 (43.7) |
Prephase steroid response | |
Good/Poor | 370 (91.4)/35 (8.6) |
Steroid used during treatment | |
Dexamethasone/Prednisolone | 146 (36.0)/259 (64.0) |
CR after remission induction | |
Yes/No | 392 (96.8)/13 (3.2) |
Risk group | |
Low/Standard | 94 (23.2)/80 (19.8) |
High/Very high | 114 (28.1)/117 (28.9) |
CNS, central nervous system; CR, complete remission; NCI, National Cancer Institute; WBC, white blood cell.
a)CNS involvement defined as CNS3 (≥ 5/μL WBCs and cytospin positive for blasts). One patient without initial CNS study,
b)A good response to 1 week of prephase steroid treatment defined as peripheral blast count < 1.0×109/L.
No. (%) (n=403) | |
---|---|
ETV6-RUNX1 | 93 (23.1) |
E2A-PBX1 | 31 (7.7) |
BCR-ABL1 | 31 (7.7) |
KMT2A rearrangement | 23 (5.7) |
High hyperdiploidy |
91 (22.6) |
Hypodiploidy |
2 (0.5) |
Normal karyotype | 50 (12.4) |
Others | 82 (20.3) |
a)Two patients without initial genetic study,
b)Defined as 51–70 chromosomes,
c)Defined as ≤ 44 chromosomes.
No. (%) (n=91) | |
---|---|
Relapse | 78 (85.7) |
Isolated BM relapse | 62 (68.1) |
Isolated EM relapse | 11 (12.1) |
Isolated CNS relapse | 8 (8.8) |
Isolated testis relapse | 3 (3.3) |
Combined BM and EM relapse | 5 (5.5) |
BM and CNS relapse | 4 (4.4) |
BM and other EM site relapse | 1 (1.1) |
Death in CR | 9 (9.9) |
Death during remission induction | 4 (4.4) |
BM, bone marrow; CNS, central nervous system; CR, complete remission; EM, extramedullary.
Patients (events) | 10-Year EFS (±SE, %) | p-value | |
---|---|---|---|
Sex | |||
Male | 243 (65) | 71.7±3.1 | 0.016 |
Female | 162 (26) | 83.4±3.0 | |
Age at diagnosis (yr) | |||
< 1 | 21 (12) | 42.9±10.8 | < 0.001 |
1 to < 10 | 274 (48) | 80.8±2.6 | |
≥ 10 | 110 (31) | 71.5±4.5 | |
WBC at diagnosis (×109/L) | |||
< 50 | 309 (56) | 80.3±2.5 | < 0.001 |
≥ 50 and < 100 | 40 (10) | 74.1±7.1 | |
≥ 100 | 56 (25) | 56.5±6.7 | |
Initial CNS involvement | |||
No | 398 (86) | 77.1±2.3 | < 0.001 |
Yes | 6 (4) | 33.3±19.2 | |
Prephase steroid response | |||
Good | 370 (75) | 78.1±2.3 | < 0.001 |
Poor | 35 (16) | 57.1±8.4 | |
Genetic abnormality | |||
ETV6-RUNX1 | 93 (18) | 79.5±4.4 | < 0.001 |
E2A-PBX1 | 31 (4) | 87.1±6.0 | |
BCR-ABL1 | 31 (15) | 50.5±9.2 | |
KMT2A | 23 (10) | 56.5±10.3 | |
High hyperdiploidy | 91 (8) | 91.2±3.0 | |
Hypodiploidy | 2 (1) | 0 | |
Normal | 50 (13) | 75.1±6.3 | |
Others | 82 (20) | 73.3±5.3 | |
Steroid used | |||
Dexamethasone | 146 (27) | 82.1±3.2 | 0.048 |
Prednisolone | 259 (64) | 70.3±4.3 |
CNS, central nervous system; EFS, event-free survival; SE, standard error; WBC, white blood cell.
Hazard ratio (95% CI) | p-value | |
---|---|---|
Sex | ||
Female | 1 | |
Male | 1.74 (1.07–2.84) | 0.025 |
Patient age (yr) | ||
1 to < 10 | 1 | |
< 1 | 3.52 (1.44–8.63) | 0.006 |
Initial CNS involvement | ||
No | 1 | (0.003 |
Yes | 5.56 (1.80–17.23) | |
Genetic abnormality | ||
ETV6-RUNX1 | 1 | |
BCR-ABL1 | 2.44 (1.07–5.54) | 0.034 |
High hyperdiploidy | 0.41 (0.18–0.93) | 0.034 |
CI, confidence interval; CNS, central nervous system; EFS, event-free survival.
CNS, central nervous system; CR, complete remission; NCI, National Cancer Institute; WBC, white blood cell. CNS involvement defined as CNS3 (≥ 5/μL WBCs and cytospin positive for blasts). One patient without initial CNS study, A good response to 1 week of prephase steroid treatment defined as peripheral blast count < 1.0×109/L.
Two patients without initial genetic study, Defined as 51–70 chromosomes, Defined as ≤ 44 chromosomes.
BM, bone marrow; CNS, central nervous system; CR, complete remission; EM, extramedullary.
CNS, central nervous system; EFS, event-free survival; SE, standard error; WBC, white blood cell.
CI, confidence interval; CNS, central nervous system; EFS, event-free survival.