tjh-v38i2

Turk J Hematol 2021;38:138-144
Aladağ E. et al: Risk Scores in Stem Cell Transplantation
on 2-year OS (AL-EBMT: reference vs. score 8.5-10, HR: 1.3,
p=0.035; AL-EBMT: reference vs. score >10, HR: 3.8, p=0.001;
HCT-CI: reference vs. score 1-2, HR: 1.4, p=0.018; HCT-CI:
reference vs. score ≥3, HR: 2.5, p<0.001; HCT-CI-Age: reference
vs. score 1-2, HR: 1.3, p<0.001; HCT-CI-Age: reference vs. score
≥3, HR: 3.2, p<0.001) (Figure 1). C statistics of these scoring
systems for 2-year OS were 0.59, 0.52, and 0.56, respectively.
While OS was not observed in the group with rPAM scores of
17-24, 2-year OS was found to be significantly higher in patients
with rPAM scores of 24-30 and >30 compared to the reference
group (rPAM: reference vs. score 24-30, HR 1.8, p=0.037; rPAM:
reference vs. score >30, HR 3.6, p=0.012).
Discussion
The aim of the present study was to test and validate 6 different
transplantation risk scores in a patient group. We found high
predictive value for 2-year NRM and 2-year OS using the HCT-
CI, HCT-CI-Age, and AL-EBMT scores. In our study, the C statistics
for both models were rather low (<0.65), and there was a trend
toward better predictive capacity for the AL-EBMT compared
with the HCT-CI and HCT-CI-Age scores.
The vast majority of risk-based scoring systems are validated
with well-defined broad cohorts. Many studies have been
published comparing these scoring systems. However, studies
generally only evaluate 2 different scores [8,11,28,29]. The
present study contributes to the literature in terms of applying
6 different scoring systems for the same patients. To the best
of our knowledge, there is only one study in the literature that
compared more than 3 risk scoring systems [6]. In that study, 8
different scoring systems were evaluated among 528 patients
(EBMT, HCT-CI, Comorbidity-Age, Comorbidity-EBMT, rDRI,
PAM, rPAM, and EASIx); among all of them, the models with
Table 2. Two-year overall survival and non-relapse mortality according to the risk scoring systems.
EBMT
n 2-year OS, % (95% CI) HR p 2-year NRM (95% CI) HR p
0-2 135 87.2 (72-91.2) Reference 7.1 (6.9-7.3) 1
3 73 78.6 (72.2-81.1) 1.1 (0.7-1.8) 0.476 9.4 (7.3-14.6) 1.2 (1.1-1.5) 0.272
4 23 80.2 (52.2-81.4) 1.3 (0.5-2.2) 0.673 11.1 (8-14.1) 1.4 (1.1-2.7) 0.284
5 28 60.9 (55.6-65.6) 1.8 (1-3.1) 0.043 14.4 (11.2-19.1) 2.4 (1.4-4.3) 0.001
AL-EBMT
<8.5 163 81.2 (74.1-97.2) Reference 3.1 (1-5.1) Reference
8.5-10 23 77.4 (70.2-81.5) 1.3 (0.6-2.7) 0.035 14.3 (11.6-21.1) 1.6 (0.8-3.1) <0.001
>10 24 33.1 (30.6-36.1) 3.8 (2.1-6.7) 0.001 27 (18-29.1) 3.3 (1.9-4.8) <0.001
rPAM
<17 217 84.2 (72.1-86.2) Reference 9.1 (7.7-12.1) Reference
17-24 14 80.2 (55.1-79,8) 2 (0.9-4.2) 0.056 10.2 (6.4-16.1) 1.8 (0.8-4) 0.109
24-30 24 61.2 (52.3-63.4) 1.8 (1-3.3) 0.037 17.2 (4.1-19.2) 1.7 (0.9-3.1) 0.055
>30 4 50.1 (22.2-57.3) 3.6 (1.3-9.9) 0.012 - 2.7 (1.1-8.7) 0.084
HCT-CI
0 175 84.2 (72.1-86.1) Reference 11.2 (8.2-14.1) Reference
1-2 66 72.2 (59.1-79.9) 1.4 (0.9-2.3) 0.018 16.2 (13-17.2) 1.3 (1.2-2.1) 0.028
≥3 18 56.2 (41.3- 57.2) 2.5 (1.2-5) <0.001 24.6 (14.6-26.2) 2.3 (1.2-4.6) 0.011
HCT-CI-A
0 106 84.2 (76.2-83.3) Reference 4.1 (1.3-5.2) Reference
1-2 117 71.9 (66.1-79.9) 1.3 (1.03-2.1) <0.001 14.6 (11.1-16.4) 1.3 (1.1-2) 0.01
≥3 36 49.1 (42.3-57.1) 3.2 (5.8-3.9) <0.001 21.2 (16.2-24.4) 2.4 (1.3-4.4) 0.003
DRI
Low 40 81.5 (74.2-85.2) Reference 7.4 (6.9-8.2) Reference
Intermediate 174 80 (62.9-79.1) 1.1 (0.6-1.9) 0.68 9.1 (6.7-13.4) 1.1 (0.6-2) 0.31
High 31 65.7 (57.7-71.5) 1.6 (0.8-3.4) 0.11 13.5 (12.2-16.2) 2.3 (1.1-4.7) 0.12
Very high 14 47.6 (42.8-62.6) 1.7 (0.7-4.3) 0.22 - - -
OS: Overall survival, NRM: non-relapse mortality; HR: hazard ratio; CI: confidence interval; EBMT: European Society for Blood and Marrow Transplantation; AL-EBMT: Acute Leukemia-
EBMT score; rPAM: revised Pretransplant Assessment of Mortality Score; HCT-CI: Hematopoietic Cell Transplantation Comorbidity Index; HCT-CI-A: Age-Adjusted Hematopoietic Cell
Transplantation Comorbidity Index; DRI: Disease Risk Index.
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