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Reduced 8-Gray Compared to Standard 12-Gray Total Body Irradiation for Allogeneic Transplantation in First Remission Acute Lymphoblastic Leukemia: A Study of the Acute Leukemia Working Party of the EBMT
Spyridonidis, A., Labopin, M., Savani, B., Giebel, S., Bug, G., Schönland, S., Kröger, N., Stelljes, M., Schroeder, T., McDonald, A., et al
HemaSphere. 2023;7(1):e812
Abstract
In this registry-based study, we compared outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) in adult patients with acute lymphoblastic leukemia (ALL) transplanted in first complete remission (CR-1), following conditioning with total body irradiation (TBI) at a standard 12-Gray or at a lower 8-Gray total dose. Patients received fludarabine (flu) as the sole chemotherapy complementing TBI. Eight-Gray TBI/flu was used in 494 patients and 12-Gray TBI/flu in 145 patients. Eighty-eight (23.1%) and 36 (29%) of the patients had Ph-negative B-ALL, 222 (58.3%) and 53 (42.7%) had Ph-positive B-ALL, 71 (18.6%) and 35 (28.2%) T-ALL, respectively (P = 0.008). Patients treated with 8-Gray were older than ones received 12-Gray (median 55.7 versus 40.3 years, P < 0.0001) and were more frequently administered in vivo T-cell depletion (71% versus 40%, P <0.0001). In a multivariate model adjusted for age, type of ALL, and other prognostic factors, leukemia-free survival (primary endpoint) as well as relapse, nonrelapse mortality, overall survival, and GVHD-free, relapse-free survival were not influenced by the TBI dose. These results were confirmed when we focused on patients <55 years of age (median 47 years). Patients with Ph-positive ALL or T-ALL had significantly better survival outcomes than ones with Ph-negative B-ALL, mainly due to significantly fewer relapses. We conclude that 8-Gray TBI is sufficient for adult patients with ALL transplanted in CR-1 with no additional benefit of augmenting the conditioning intensity to 12-Gray.
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Total body irradiation versus busulfan based intermediate intensity conditioning for stem cell transplantation in ALL patients >45 years-a registry-based study by the Acute Leukemia Working Party of the EBMT
Hirschbühl, K., Labopin, M., Polge, E., Blaise, D., Bourhis, J. H., Socié, G., Forcade, E., Yakoub-Agha, I., Labussière-Wallet, H., Bethge, W., et al
Bone marrow transplantation. 2023
Abstract
Allogeneic hematopoietic cell transplantation is a potentially curative treatment in high-risk acute lymphoblastic leukemia (ALL). Conditioning regimens based on ≥12 Gray total body irradiation (TBI) represent the current standard in patients ≤45 years, whereas elderly patients frequently receive intermediate intensity conditioning (IIC) to reduce toxicity. To evaluate the role of TBI as a backbone of IIC in ALL, a retrospective, registry-based study included patients >45 years transplanted from matched donors in first complete remission, who had received either fludarabine/TBI 8 Gy (FluTBI8, n = 262), or the most popular, irradiation-free alternative fludarabine/busulfan, comprising busulfan 6.4 mg/kg (FluBu6.4, n = 188) or 9.6 mg/kg (FluBu9.6, n = 51). At two years, overall survival (OS) was 68.5%, 57%, and 62.2%, leukemia-free survival (LFS) was 58%, 42.7%, and 45%, relapse incidence (RI) was 27.2%, 40%, and 30.9%, and non-relapse-mortality (NRM) was 23.1%, 20.7%, and 26.8% for patients receiving FluTBI8Gy, FluBu6.4, and FluBu9.6, respectively. In multivariate analysis, the risk of NRM, acute and chronic graft-versus-host disease was not influenced by conditioning. However, RI was higher after FluBu6.4 (hazard ratio [HR] [95% CI]: 1.85 [1.16-2.95]), and LFS was lower after both FluBu6.4 (HR: 1.56 [1.09-2.23]) and FluBu9.6 (HR: 1.63 [1.02-2.58]) as compared to FluTBI8. Although only resulting in a non-significant advantage in OS, this observation indicates a stronger anti-leukemic efficacy of TBI-based intermediate intensity conditioning.
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Autologous versus allogeneic hematopoietic cell transplantation for older patients with acute lymphoblastic leukemia. An analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation
Giebel, S., Labopin, M., Houhou, M., Caillot, D., Finke, J., Blaise, D., Fegueux, N., Ethell, M., Cornelissen, J. J., Forcade, E., et al
Bone marrow transplantation. 2023;58(4):393-400
Abstract
Allogeneic hematopoietic cell transplantation (allo-HCT) with reduced intensity conditioning (RIC) is an option for elderly patients with acute lymphoblastic leukemia (ALL). We retrospectively compared results of RIC-allo-HCT from either a matched sibling donor (MSD, n = 209) or matched unrelated donor (MUD, n = 209) with autologous (auto, n = 142) HCT for patients aged 55 years or more treated in first complete remission (CR1) between 2000 and 2018. The probabilities of leukemia-free survival (LFS) at 5 years were 34% for RIC-allo-HCT versus 39% for auto-HCT (p = 0.11) while overall survival (OS) rates were 42% versus 45% (p = 0.23), respectively. The incidence of relapse (RI) and non-relapse mortality (NRM) was 41% versus 51% (p = 0.22) and 25% versus 10% (p = 0.001), respectively. In a multivariate model, using auto-HCT as reference, the risk of NRM was increased for MSD-HCT (Hazard ratio [HR] = 2.1, p = 0.02) and MUD-HCT (HR = 3.08, p < 0.001), which for MUD-HCT translated into a decreased chance of LFS (HR = 1.55, p = 0.01) and OS (HR = 1.62, p = 0.008). No significant associations were found with respect to the risk of relapse. We conclude that for patients with ALL in CR1, aged above 55 years, auto-HCT may be considered a transplant option alternative to RIC-allo-HCT, although its value requires verification in prospective trials.
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Posttransplant cyclophosphamide versus antithymocyte globulin in patients with acute lymphoblastic leukemia treated with allogeneic hematopoietic cell transplantation from matched unrelated donors. A study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation
Giebel, S., Labopin, M., Salmenniemi, U., Socié, G., Bondarenko, S., Blaise, D., Kröger, N., Vydra, J., Grassi, A., Bonifazi, F., et al
Cancer. 2023
Abstract
BACKGROUND The aim of this study was to compare two immunosuppressive strategies, based on the use of either rabbit antithymocyte globulin (ATG) or posttransplant cyclophosphamide (PTCY), as a prophylaxis of graft-versus-host disease (GVHD) for patients with acute lymphoblastic leukemia (ALL) in first complete remission who underwent hematopoietic cells transplantation from matched unrelated donors. METHODS Overall, 117 and 779 adult patients who received PTCY and ATG, respectively, between the years 2015 and 2020 were included in this retrospective study. The median patient age was 40 and 43 years in the PTCY and ATG groups, respectively, and 37% and 35% of patients, respectively, had Philadelphia chromosome-positive ALL. RESULTS In univariate analysis, the cumulative incidence of acute and chronic GVHD did not differ significantly between the study groups. The cumulative incidence of relapse at 2 years was reduced in the PTCY group (18% vs. 25%; p = .046) without a significant impact on nonrelapse mortality (11% vs. 16% in the ATG group; p = .29). The rates of leukemia-free survival (LFS) and overall survival were 71% versus 59%, respectively (p = .01), and 82% versus 74%, respectively (p = .08). In multivariate analysis, the receipt of ATG compared with PTCY was associated with a reduced risk of extensive chronic GVHD (hazard ratio, 0.54; 95% confidence interval, 0.3-0.98; p = .04) and an increased risk of low LFS (hazard ratio, 1.57; 95% confidence interval, 1.01-2.45; p = .045). CONCLUSIONS The receipt of ATG compared with PTCY, despite the reduced risk of extensive chronic GVHD, is associated with inferior LFS in adults with ALL who undergo hematopoietic cell transplantation from 10/10 human leukocyte antigen-matched unrelated donors. These findings warrant verification in prospective trials.
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Fludarabine or cyclophosphamide in combination with total body irradiation as myeloablative conditioning prior to allogeneic hematopoietic cell transplantation for acute lymphoblastic leukemia: an analysis by the Acute Leukemia Working Party of the EBMT
Giebel, S., Labopin, M., Socié, G., Aljurf, M., Salmenniemi, U., Labussière-Wallet, H., Srour, M., Kröger, N., Zahrani, M. A., Lioure, B., et al
Bone marrow transplantation. 2023
Abstract
In this registry-based study we retrospectively compared outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) for adult patients with acute lymphoblastic leukemia (ALL) following conditioning with total body irradiation (TBI) combined with either cyclophosphamide (Cy) or fludarabine (Flu). TBI 12 Gy + Cy was used in 2105 cases while TBI 12 Gy + Flu was administered to 150 patients in first or second complete remission. In a multivariate model adjusted for other prognostic factors, TBI/Cy conditioning was associated with a reduced risk of relapse (HR = 0.69, p = 0.049) and increased risk of grade 2-4 acute graft-versus-host disease (GVHD, HR = 1.57, p = 0.03) without significant effect on other transplantation outcomes. In a matched-pair analysis the use of TBI/Cy as compared to TBI/Flu was associated with a significantly reduced rate of relapse (18% vs. 30% at 2 years, p = 0.015) without significant effect on non-relapse mortality, GVHD and survival. We conclude that the use of myeloablative TBI/Cy as conditioning prior to allo-HCT for adult patients with ALL in complete remission is associated with lower risk of relapse rate compared to TBI/Flu and therefore should probably be considered a preferable regimen.
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Thiotepa-based regimens are a valid alternative to total body irradiation-based reduced-intensity conditioning regimens in patients with acute lymphoblastic leukemia: a retrospective study on behalf of the Acute Leukemia Working Party of the EBMT
Battipaglia, G., Labopin, M., Mielke, S., Ruggeri, A., Nur Ozkurt, Z., Henri Bourhis, J., Rabitsch, W., Yakoub-Agha, I., Grillo, G., Sanz, J., et al
Transplantation and cellular therapy. 2023
Abstract
INTRODUCTION Total body irradiation (TBI) at myeloablative doses is superior to chemotherapy-based regimens in young patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, in elderly and unfit patients, where reduced-intensity conditioning (RIC) regimens are preferred, whether a TBI- or chemotherapy-based approach is better, is unexplored. Thiotepa can be used as part of ALL conditioning regimens. The aim of the current study is to compare transplant outcomes after RIC with TBI- or thiotepa-based regimens in ALL. METHODS Included were patients aged ≥40 years undergoing allo-HSCT for ALL in first complete remission between 2000-2020, receiving a RIC regimen containing either TBI- (4-6 Gray, Gy) or thiotepa. RESULTS We identified a total of 265 patients, including 117 receiving TBI- and 148 receiving a thiotepa-based RIC regimen. In univariate analysis, no differences were observed in transplant outcomes (for TBI versus thiotepa: relapse, 23% versus 28%, p=0.24; non-relapse mortality, 20% versus 26%, p=0.61; leukemia-free survival, 57% versus 46%, p=0.12; overall survival, 67% versus 56%, p=0.18; graft-versus-host disease [GVHD]/relapse-free survival, 45% versus 38%, p=0.21; grade II-IV acute GVHD, 30% in both groups, p=0.84; grade III-IV acute GVHD, 9% versus 10%, p=0.89) except for chronic GVHD which was higher for TBI-based regimens (43% versus 29%, p=0.03). However, on multivariate analysis no differences in transplant outcomes were observed. CONCLUSION In patients ≥40 years receiving a RIC regimen, use of a thiotepa-based regimen may represent a valid alternative to TBI-based regimens as no differences were observed in the main transplant outcomes.
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Posttransplant cyclophosphamide-based anti-graft-vs-host disease prophylaxis in patients with acute lymphoblastic leukemia treated in complete remission with allogeneic hematopoietic cell transplantation from human leukocyte antigen-mismatched unrelated donors versus haploidentical donors: A study on behalf of the ALWP of the EBMT
Nagler, A., Labopin, M., Arat, M., Reményi, P., Koc, Y., Blaise, D., Angelucci, E., Vydra, J., Kulagin, A., Socié, G., et al
Cancer. 2022
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Editor's Choice
Abstract
BACKGROUND Both mismatched unrelated donor (MMUD) and haploidentical (haplo) transplantation are valid options in patients with high-risk acute lymphoblastic leukemia (ALL) lacking a matched donor. METHODS The study compared the outcomes of adult patients with ALL in complete remission (CR) who underwent 9/10 MMUD versus haplo transplantation with posttransplant cyclophosphamide (PTCy) as graft-vs-host disease (GVHD) prophylaxis in 2010-2020. RESULTS The study included 781 patients (MMUD, 103; haplo, 678). The median age was 40 (19-73) and 38 (18-75) years, respectively (p = .51). The most frequent immunosuppression agents added to PTCy were mycophenolate mofetil (MMF)/cyclosporine A and MMF/tacrolimus. In vivo T-cell depletion (anti-thymocyte globulin) was administered to 21% and 8% of the transplants, respectively (p < .0001). Neutrophil (absolute neutrophil count >0.5 × 10(9) /L) recovery was achieved in 97.1% versus 96.7% versus (p = 1) in MMUD and haplo, respectively. Nonrelapse mortality and relapse incidence were not significantly different between MMUD and haplo, hazard ratio (HR) = 1.45 (95% confidence interval [CI], 0.81-2.62; p = .21) and HR = 0.81 (95% CI, 0.52-1.28, p = .38), respectively. HRs for leukemia-free survival, overall survival, and GVHD-free, relapse-free survival were respectively, HR = 1.05 (95% CI, 0.73-1.50, p = .8), HR = 1.17 (95% CI, 0.77-1.76, p = .46), and HR = 1.07 (95% CI, 0.78-1.46, p = .7) for haplo compared to MMUD. Acute (a)GVHD grade 2-4 was significantly higher with haplo, HR = 1.73 (95% CI, 1.08-2.76, p = .023), whereas aGVHD grade 3-4 and chronic GVHD did not differ significantly between the two transplant groups. CONCLUSION Outcomes of MMUD and haplo transplants with PTCy-based GVHD prophylaxis for ALL patients in CR are similar, apart from a higher incidence of aGVHD with haplo transplants.
PICO Summary
Population
Adults with high-risk acute lymphoblastic leukemia (ALL) in complete remission, lacking a matched donor (n=781)
Intervention
9/10 mismatched unrelated donor transplantation (MMUD, n=103)
Comparison
Haploidentical transplantation (haplo, n=678)
Outcome
Neutrophil (absolute neutrophil count >0.5 × 10(9) /L) recovery was achieved in 97.1% versus 96.7% versus in MMUD and haplo, respectively. Nonrelapse mortality and relapse incidence were not significantly different between MMUD and haplo, hazard ratio (HR) = 1.45 (95% confidence interval [CI], 0.81-2.62) and HR = 0.81 (95% CI, 0.52-1.28), respectively. HRs for leukemia-free survival, overall survival, and GVHD-free, relapse-free survival were respectively, HR = 1.05 (95% CI, 0.73-1.50), HR = 1.17 (95% CI, 0.77-1.76), and HR = 1.07 (95% CI, 0.78-1.46) for haplo compared to MMUD. Acute (a)GVHD grade 2-4 was significantly higher with haplo, HR = 1.73 (95% CI, 1.08-2.76), whereas aGVHD grade 3-4 and chronic GVHD did not differ significantly between the two transplant groups.
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Total body irradiation plus fludarabine versus thiotepa, busulfan plus fludarabine as a myeloablative conditioning for adults with acute lymphoblastic leukemia treated with haploidentical hematopoietic cell transplantation. A study by the Acute Leukemia Working Party of the EBMT
Swoboda, R., Labopin, M., Giebel, S., Angelucci, E., Arat, M., Aljurf, M., Sica, S., Pavlu, J., Socié, G., Bernasconi, P., et al
Bone marrow transplantation. 2022
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Editor's Choice
Abstract
Optimal conditioning for adults with acute lymphoblastic leukemia (ALL) treated with haploidentical hematopoietic cell transplantation (haplo-HCT) and post-transplant cyclophosphamide has not been established so far. We retrospectively compared outcomes for two myeloablative regimens: fludarabine + total body irradiation (Flu-TBI, n = 117) and thiotepa + iv. busulfan + fludarabine (TBF, n = 119). Patients transplanted either in complete remission (CR) or with active disease were included in the analysis. The characteristics of both groups were comparable except for patients treated with TBF were older. In univariate analysis the incidence of non-relapse mortality (NRM) at 2 years was increased for TBF compared to Flu-TBI (31% vs. 19.5%, p = 0.03). There was a tendency towards reduced incidence of relapse after TBF (p = 0.11). Results of multivariate analysis confirmed a reduced risk of NRM using Flu-TBI (HR = 0.49, p = 0.03). In the analysis restricted to patients treated in CR1 or CR2, the use of Flu-TBI was associated with a decreased risk of NRM (HR = 0.34, p = 0.009) but an increased risk of relapse (HR = 2.59, p = 0.01) without significant effect on survival and graft-versus-host disease. We conclude that for haplo-HCT recipients with ALL, Flu-TBI may be preferable for individuals at high risk of NRM while TBF should be considered in cases at high risk of relapse.
PICO Summary
Population
Adults with acute lymphoblastic leukemia (ALL) treated with haploidentical (n=haematopoietic cell transplantation (haplo-HCT) and post-transplant cyclophosphamide (n=236)
Intervention
Fludarabine + total body irradiation conditioning (Flu-TBI, n=117)
Comparison
Thiotepa + iv. busulfan + fludarabine conditioning (TBF, n=119)
Outcome
In univariate analysis the incidence of non-relapse mortality (NRM) at 2 years was increased for TBF compared to Flu-TBI (31% vs. 19.5%). There was a tendency towards reduced incidence of relapse after TBF. Results of multivariate analysis confirmed a reduced risk of NRM using Flu-TBI (HR = 0.49). In the analysis restricted to patients treated in CR1 or CR2, the use of Flu-TBI was associated with a decreased risk of NRM (HR = 0.34) but an increased risk of relapse (HR = 2.59) without significant effect on survival and graft-versus-host disease.
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CNS Involvement at Initial Diagnosis and Risk of Relapse After Allogeneic HCT for Acute Lymphoblastic Leukemia in First Complete Remission
Kharfan-Dabaja, M. A., Labopin, M., Bazarbachi, A., Salmenniemi, U., Mielke, S., Chevallier, P., Thérèse Rubio, M., Balsat, M., Pioltelli, P., Menard, A. L., et al
HemaSphere. 2022;6(11):e788
Abstract
Outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) for adult acute lymphoblastic leukemia (ALL) have improved over time. Studies have shown that total body irradiation (TBI) is the preferable type of myeloablative conditioning (MAC). However, outcomes based on central nervous system (CNS) involvement, namely CNS-positive versus CNS-negative, have not been compared. Here, we evaluated outcomes of 547 patients (CNS-positive = 96, CNS-negative = 451) who were allografted in the first complete remission (CR1) between 2009 and 2019. Primary endpoint was leukemia-free survival (LFS). Median follow-up was not different between the CNS-positive and CNS-negative groups (79 versus 67.2 months, P = 0.58). The CNS-positive group were younger (median age 31.3 versus 39.7 years, P = 0.004) and were allografted more recently (median year 2012 versus 2010, P = 0.003). In both groups, MAC was the preferred approach (82.3% versus 85.6%, P = 0.41). On multivariate analysis, the CNS-positive group had higher incidence of relapse (RI) (hazard ratio [HR] = 1.58 [95% confidence interval (CI) = 1.06-2.35], P = 0.025), but no adverse effect on LFS (HR = 1.38 [95% CI = 0.99-1.92], P = 0.057) or overall survival (OS) (HR = 1.28 [95% CI = 0.89-1.85], P = 0.18). A subgroup multivariate analysis limited to CNS-positive patients showed that a TBI-based MAC regimen resulted in better LFS (HR = 0.43 [95% CI = 0.22-0.83], P = 0.01) and OS (HR = 0.44 [95% CI = 0.21-0.92], P = 0.03) and lower RI (HR = 0.35 [95% CI = 0.15-0.79], P = 0.01). Another subgroup analysis in CNS-negative patients showed that MAC-TBI preparative regimens also showed a lower RI without a benefit in LFS or OS. While a MAC-TBI allo-HCT regimen may not be suitable to all, particularly for older patients with comorbidities, this approach should be considered for patients who are deemed fit and able to tolerate.
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Outcome of T-cell-replete haploidentical stem cell transplantation improves with time in adults with acute lymphoblastic leukemia: A study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation
Nagler, A., Labopin, M., Koc, Y., Angelucci, E., Tischer, J., Arat, M., Pioltelli, P., Bernasconi, P., Chiusolo, P., Diez-Martin, J. L., et al
Cancer. 2021
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Editor's Choice
Abstract
BACKGROUND The use of haploidentical hematopoietic cell transplantation (haplo-HCT) with posttransplantation cyclophosphamide prophylaxis is gaining traction in patients with acute lymphoblastic leukemia (ALL). METHODS The Acute Leukemia Working Party/European Society for Blood and Marrow Transplantation registry was used to evaluate the outcomes of adult patients with ALL who underwent haplo-HCT during 2011 through 2015 and compared them with the outcomes of those who underwent transplantation during 2016 through 2018. RESULTS The analysis consisted of 195 patients, including 79 who underwent transplantation during 2011 through 2015 and 116 who underwent transplantation during 2016 through 2018. Overall, the 2-year leukemia-free survival and relapse incidence rates were 56.5% and 21%, respectively. The 100-day incidence of grade 2 through 4 acute graft-vs-host disease (GVHD) was 34.5%. The rates of nonrelapse mortality (NRM) and overall survival (OS) were 22.5% and 64.7%, respectively. Patients who underwent transplantation during 2016 through 2018 experienced improved rates of leukemia-free survival (64.9% vs 47.3%; P = .019) and OS (75.5% vs 53.5%; P = .006). Patients who underwent transplantation during 2016 through 2018 developed more grade 2 through 4 acute GVHD (42% vs 26.4%; P = .047). The incidence of relapse, GVHD-free/relapse-free survival, grade 3 and 4 acute GVHD, chronic GVHD, and extensive chronic GVHD did not differ significantly between groups. In multivariate analysis, more recently transplanted patients had a significantly reduced risk of NRM (hazard ratio, 0.44; 95% CI, 0.22-0.89; P = .022) and improved OS (hazard ratio, 0.47; 95% CI, 0.26-0.86; P = .014). A comparable analysis of patients who had acute myeloid leukemia during the same timeframes did not reveal any statistically significant differences in any outcomes. CONCLUSIONS The outcome of adult patients with ALL who receive posttransplant cyclophosphamide has improved over time, with an impressive 2-year OS of 75% and, most recently, an NRM rate of only 17%.
PICO Summary
Population
Adult patients undergoing haploidentical transplantation for acute lymphoblastic leukemia reported to the EBMT registry (n=195)
Intervention
Haploidentical transplantation between 2016-2018 (n=116)
Comparison
Haploidentical transplantation between 2011-2015 (n=79)
Outcome
For the entire cohort, the 2-year leukemia-free survival and relapse incidence rates were 56.5% and 21%, respectively. The 100-day incidence of grade 2 through 4 acute graft-vs-host disease (GVHD) was 34.5%. The rates of non-relapse mortality (NRM) and overall survival (OS) were 22.5% and 64.7%, respectively. Patients who underwent transplantation during 2016 through 2018 experienced improved rates of leukemia-free survival (64.9% vs 47.3%) and OS (75.5% vs 53.5%). Patients who underwent transplantation during 2016 through 2018 developed more grade 2 through 4 acute GVHD (42% vs 26.4%). The incidence of relapse, GVHD-free/relapse-free survival, grade 3 and 4 acute GVHD, chronic GVHD, and extensive chronic GVHD did not differ significantly between groups. In multivariate analysis, more recently transplanted patients had a significantly reduced risk of NRM (hazard ratio, 0.44) and improved OS (hazard ratio, 0.47). A comparable analysis of patients who had acute myeloid leukemia during the same timeframes did not reveal any statistically significant differences in any outcomes.