Allogeneic hematopoietic cell transplantation for blastic plasmacytoid dendritic cell neoplasm: a CIBMTR analysis.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy with a poor prognosis and considered incurable with conventional chemotherapy. Small observational studies reported allogeneic hematopoietic cell transplantation (allo-HCT) offers durable remissions in patients with BPDCN. We report an analysis of patients with BPDCN who received an allo-HCT, using data reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). We identified 164 patients with BPDCN from 78 centers who underwent allo-HCT between 2007 and 2018. The 5-year overall survival (OS), disease-free survival (DFS), relapse, and nonrelapse mortality (NRM) rates were 51.2% (95% confidence interval [CI], 42.5-59.8), 44.4% (95% CI, 36.2-52.8), 32.2% (95% CI, 24.7-40.3), and 23.3% (95% CI, 16.9-30.4), respectively. Disease relapse was the most common cause of death. On multivariate analyses, age of ≥60 years was predictive for inferior OS (hazard ratio [HR], 2.16; 95% CI, 1.35-3.46; P = .001), and higher NRM (HR, 2.19; 95% CI, 1.13-4.22; P = .02). Remission status at time of allo-HCT (CR2/primary induction failure/relapse vs CR1) was predictive of inferior OS (HR, 1.87; 95% CI, 1.14-3.06; P = .01) and DFS (HR, 1.75; 95% CI, 1.11-2.76; P = .02). Use of myeloablative conditioning with total body irradiation (MAC-TBI) was predictive of improved DFS and reduced relapse risk. Allo-HCT is effective in providing durable remissions and long-term survival in BPDCN. Younger age and allo-HCT in CR1 predicted for improved survival, whereas MAC-TBI predicted for less relapse and improved DFS. Novel strategies incorporating allo-HCT are needed to further improve outcomes.

A prospective phase 2 clinical trial of a C5a complement inhibitor for acute GVHD with lower GI tract involvement.

Involvement of lower gastrointestinal tract (LGI) occurs in 60% of patients with graft-versus-host-disease (GVHD). Complement components C3 and C5 are involved in GVHD pathogenesis. In this phase 2a study, we evaluated the safety and efficacy of ALXN1007, a monoclonal antibody against C5a, in patients with newly diagnosed LGI acute GVHD receiving concomitant corticosteroid. Twenty-five patients were enrolled; one was excluded from the efficacy analysis based upon negative biopsy. Most patients (16/25, 64%) had acute leukemia; 52% (13/25) had an HLA-matched unrelated donor; and 68% (17/25) received myeloablative conditioning. Half the patients (12/24) had a high biomarker profile, Ann Arbor score 3; 42% (10/24) had high-risk GVHD per Minnesota classification. Day-28 overall response was 58% (13/24 complete response, 1/24 partial response), and 63% by Day-56 (all complete responses). Day-28 overall response was 50% (5/10) in Minnesota high-risk and 42% (5/12) in high-risk Ann Arbor patients, increasing to 58% (7/12) by Day-56. Non-relapse mortality at 6-months was 24% (95% CI 11-53). The most common treatment-related adverse event was infection (6/25, 24%). Neither baseline complement levels (except for C5), activity, nor inhibition of C5a with ALXN1007 correlated with GVHD severity or responses. Further studies are needed to evaluate the role of complement inhibition in GVHD treatment.

The mutational landscape in chronic myelomonocytic leukemia and its impact on allogeneic hematopoietic cell transplantation outcomes: a Center for Blood and Marrow Transplantation Research (CIBMTR) analysis.

Somatic mutations are recognized as an important prognostic factor in chronic myelomonocytic leukemia (CMML). However, limited data are available regarding their impact on outcomes after allogeneic hematopoietic cell transplantation (HCT). In this registry analysis conducted in collaboration with the Center for International Blood and Marrow Transplantation Registry database/sample repository, we identified 313 adult patients with CMML (median age: 64 years, range, 28- 77) who underwent allogeneic HCT during 2001-2017 and had an available biospecimen in the form of a peripheral blood sample obtained prior to the start of conditioning. In multivariate analysis, a CMML-specific prognostic scoring system (CPSS) score of intermediate-2 (HR=1.46, P=0.049) or high (HR=3.22, P=0.0004) correlated significantly with overall survival. When the molecularly informed CPSS-Mol prognostic model was applied, a high CPSS-Mol score (HR=2 P=0.0079) correlated significantly with overall survival. The most common somatic mutations were in ASXL1 (62%), TET2 (35%), KRAS/NRAS (33% combined), and SRSF2 (31%). DNMT3A and TP53 mutations were associated with decreased overall survival (HR=1.70 [95% CI: 1.11-2.60], P=0.0147 and HR=2.72 [95% CI: 1.37-5.39], P=0.0042, respectively) while DNMT3A, JAK2, and TP53 mutations were associated with decreased disease-free survival (HR=1.66 [95% CI: 1.11-2.49], P=0.0138, HR=1.79 [95% CI: 1.06-3.03], P=0.0293, and HR=2.94 [95% CI: 1.50-5.79], P=0.0018, respectively). The only mutation associated with increased relapse was TP53 (HR=2.94, P=0.0201). Nonetheless, the impact of TP53 mutations specifically should be interpreted cautiously given their rarity in CMML. We calculated the goodness of fit measured by Harrell's C-index for both the CPSS and CPSS-Mol, which were very similar. In summary, via registry data we have determined the mutational landscape in patients with CMML who underwent allogeneic HCT, and demonstrated an association between CPSS-Mol and transplant outcomes although without major improvement in the risk prediction beyond that provided by the CPSS.

Characteristics of Graft-Versus-Host Disease (GvHD) After Post-Transplantation Cyclophosphamide Versus Conventional GvHD Prophylaxis.

Post-transplantation cyclophosphamide (PTCy) has been shown to effectively control graft-versus-host disease (GvHD) in haploidentical (Haplo) transplantations. In this retrospective registry study, we compared GvHD organ distribution, severity, and outcomes in patients with GvHD occurring after Haplo transplantation with PTCy GvHD prophylaxis (Haplo/PTCy) versus HLA-matched unrelated donor transplantation with conventional prophylaxis (MUD/conventional). We evaluated 2 cohorts: patients with grade 2 to 4 acute GvHD (aGvHD) including 264 and 1163 recipients of Haplo and MUD transplants; and patients with any chronic GvHD (cGvHD) including 206 and 1018 recipients of Haplo and MUD transplants, respectively. In comparison with MUD/conventional transplantation ± antithymocyte globulin (ATG), grade 3-4 aGvHD (28% versus 39%, P = .001), stage 3-4 lower gastrointestinal (GI) tract aGvHD (14% versus 21%, P = .01), and chronic GI GvHD (21% versus 31%, P = .006) were less common after Haplo/PTCy transplantation. In patients with grade 2-4 aGvHD, cGvHD rate after Haplo/PTCY was also lower (hazard ratio [HR] = .4, P < .001) in comparison with MUD/conventional transplantation without ATG in the nonmyeloablative conditioning setting. Irrespective of the use of ATG, non-relapse mortality rate was lower (HR = .6, P = .01) after Haplo/PTCy transplantation, except for transplants that were from a female donor into a male recipient. In patients with cGvHD, irrespective of ATG use, Haplo/PTCy transplantation had lower non-relapse mortality rates (HR = .6, P = .04). Mortality rate was higher (HR = 1.6, P = .03) during, but not after (HR = .9, P = .6) the first 6 months after cGvHD diagnosis. Our results suggest that PTCy-based GvHD prophylaxis mitigates the development of GI GvHD and may translate into lower GvHD-related non-relapse mortality rate.

Association of Chronic Graft-versus-Host Disease with Late Effects following Allogeneic Hematopoietic Cell Transplantation for Children with Hematologic Malignancy.

Chronic graft-versus-host disease (cGVHD) occurs in up to 25% of children following allogeneic hematopoietic cell transplantation (HCT) and continues to be a major cause of late morbidity and poor quality of life among long-term survivors of pediatric HCT. Late effects (LEs) of HCT are well documented in this population, and cGVHD has been identified as a risk factor for subsequent neoplasms (SNs) and several nonmalignant LEs (NM-LEs); however, the reported correlation between cGVHD and LEs varies among studies. We compared LEs occurring ≥2 years following childhood HCT for a hematologic malignancy in 2-year disease-free survivors with and without cGVHD and further evaluated the association of cGVHD features on the development of LEs. This systematic retrospective analysis used data from the Center of International Blood and Marrow Transplant Research (CIBMTR) on a large, representative cohort of 1260 survivors of pediatric HCT for hematologic malignancy to compare first malignant LEs and NM-LEs in those with a diagnosis of cGVHD and those who never developed cGVHD. The cumulative incidences of any first LE, SN, and NM-LE were estimated at 10 years after HCT, with death as a competing risk for patients with cGVHD versus no cGVHD. Cox proportional hazards models were used to evaluate the impact of cGVHD and its related characteristics on the development of first LEs. The estimated 10-year cumulative incidence of any LE in patients with and without cGVHD was 43% (95% CI, 38% to 48.2%) versus 32% (95% confidence interval [CI], 28.5% to 36.3%) (P < .001), respectively. The development of cGVHD by 2 years post-HCT was independently associated with any LE (hazard ratio [HR], 1.38; 95% CI, 1.13 to 1.68; P = .001) and NM-LE (HR, 1.37; 95% CI, 1.10 to 1.70; P = .006), but not SN (HR, 1.30; 95% CI, .73 to 2.31; P = .38). cGVHD-related factors linked with the development of an NM-LE included having extensive grade cGVHD (HR, 1.60; 95% CI, 1.23 to 2.08; P = .0005), severe cGVHD (HR, 2.25; 95% CI, 1.60 to 3.17; P < .0001), interrupted onset type (HR, 1.57; 95% CI, 1.21 to 2.05; P = .0008), and both mucocutaneous and visceral organ involvement (HR, 1.59; 95% CI, 1.24 to 2.03; P = .0002). No significant association between cGVHD-specific variables and SN was identified. Finally, the duration of cGVHD treatment of cGVHD with systemic immunosuppression was not significantly associated with SNs or NM-LEs. cGVHD was more closely associated with NM-LEs than with SNs among survivors of pediatric HCT for hematologic malignancy. In this analysis, the development of SNs was strongly associated with the use of myeloablative total body irradiation. cGVHD-related characteristics consistent with a state of greater immune dysregulation were more closely linked to NM-LEs.

Relapse and Disease-Free Survival in Patients With Myelodysplastic Syndrome Undergoing Allogeneic Hematopoietic Cell Transplantation Using Older Matched Sibling Donors vs Younger Matched Unrelated Donors.

IMPORTANCE: Matched sibling donors (MSDs) are preferred for allogeneic hematopoietic cell transplantation (allo-HCT) in myelodysplastic syndrome even if they are older. However, whether older MSDs or younger human leukocyte antigen-matched unrelated donors (MUDs) are associated with better outcomes remains unclear. OBJECTIVE: To investigate whether allo-HCT for myelodysplastic syndrome using younger MUDs would be associated with improved disease-free survival and less relapse compared with older MSDs. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study assessed data reported to the Center for International Blood and Marrow Transplant Research database from 1761 adults 50 years or older with myelodysplastic syndrome who underwent allo-HCT using an older MSD or younger MUD between January 1, 2011, and December 31, 2017, with a median follow-up of 48 months. Data analysis was performed from January 8, 2019, to December 30, 2020. INTERVENTIONS/EXPOSURES: Allo-HCT from an older MSD (donor age ≥50 years) or a younger MUD (donor age ≤35 years). MAIN OUTCOMES AND MEASURES: The primary outcome was disease-free survival. Secondary outcomes were overall survival, relapse, nonrelapse mortality, acute graft-vs-host disease (GVHD), chronic GVHD, and GVHD-free relapse-free survival. RESULTS: Of 1761 patients (1162 [66%] male; median [range] age, 64.9 [50.2-77.6] years in the MSD cohort and 66.5 [50.4-80.9] years in MUD cohort), 646 underwent allo-HCT with an older MSD and 1115 with a younger MUD. In multivariable analysis, the rate of disease-free survival was significantly lower in allo-HCTs with older MSDs compared with younger MUDs (hazard ratio [HR], 1.17; 95% CI, 1.02-1.34; P = .02), whereas the difference in overall survival rate of allo-HCT with younger MUDs vs older MSDs was not statistically significant (HR, 1.13; 95% CI, 0.98-1.29; P = .07). Allo-HCT with older MSDs was associated with significantly higher relapse (HR, 1.62; 95% CI, 1.32-1.97; P < .001), lower nonrelapse mortality (HR, 0.76; 95% CI, 0.59-0.96; P = .02), lower acute GVHD (HR, 0.52; 95% CI, 0.42-0.65; P < .001), chronic GVHD (HR, 0.77; 95% CI, 0.64-0.92; P = .005), and a lower rate of GVHD-free relapse-free survival beyond 12 months after allo-HCT (HR, 1.42; 95% CI, 1.02-1.98; P = .04). CONCLUSIONS AND RELEVANCE: This cohort study found higher disease-free survival and lower relapse for allo-HCT in myelodysplastic syndrome using younger MUDs compared with older MSDs. The risk of nonrelapse mortality and GVHD was lower with older MSDs. These results suggest that the use of younger MUDs should be considered in the donor selection algorithm for myelodysplastic syndrome, in which it is pivotal to minimize relapse given limited treatment options for managing relapsed disease.

An adapted European LeukemiaNet genetic risk stratification for acute myeloid leukemia patients undergoing allogeneic hematopoietic cell transplant. A CIBMTR analysis.

Cytogenetic and molecular abnormalities are known to influence post-transplant outcomes in acute myeloid leukemia (AML) but data assessing the prognostic value of combined genetic models in the HCT setting are limited. We developed an adapted European LeukemiaNet (aELN) risk classification based on available genetic data reported to the Center for International Blood and Marrow Transplant Research, to predict post-transplant outcomes in 2289 adult AML patients transplanted in first remission, between 2013 and 2017. Patients were stratified according to aELN into three groups: favorable (Fav, N = 181), intermediate (IM, N = 1185), and adverse (Adv, N = 923). Univariate analysis demonstrated significant differences in 2-year overall survival (OS) (Fav: 67.7%, IM: 64.9% and Adv: 53.9%; p < 0.001); disease-free survival (DFS) (Fav: 57.8%, IM: 55.5% and Adv: 45.3; p < 0.001) and relapse (Fav: 28%, IM: 27.5% and Adv: 37.5%; p < 0.001). Multivariate analysis (MVA) revealed no differences in outcomes between the Fav and IM groups, thus they were combined. On MVA, patients in the Adv risk group had the highest risk of relapse (HR 1.47 p ≤ 0.001) and inferior DFS (HR 1.35 p < 0.001) and OS (HR 1.39 p < 0.001), even using myeloablative conditioning or in those without the pre-HCT measurable-residual disease. Novel approaches to mitigate relapse in this high-risk group are urgently needed.

Impact of depth of clinical response on outcomes of acute myeloid leukemia patients in first complete remission who undergo allogeneic hematopoietic cell transplantation.

Acute myeloid leukemia (AML) patients often undergo allogeneic hematopoietic cell transplantation (alloHCT) in first complete remission (CR). We examined the effect of depth of clinical response, including incomplete count recovery (CRi) and/or measurable residual disease (MRD), in patients from the Center for International Blood and Marrow Transplantation Research (CIBMTR) registry. We identified 2492 adult patients (1799 CR and 693 CRi) who underwent alloHCT between January 1, 2007 and December 31, 2015. The primary outcome was overall survival (OS). Multivariable analysis was performed to adjust for patient-, disease-, and transplant-related factors. Baseline characteristics were similar. Patients in CRi compared to those in CR had an increased likelihood of death (HR: 1.27; 95% confidence interval: 1.13-1.43). Compared to CR, CRi was significantly associated with increased non-relapse mortality (NRM), shorter disease-free survival (DFS), and a trend toward increased relapse. Detectable MRD was associated with shorter OS, shorter DFS, higher NRM, and increased relapse compared to absence of MRD. The deleterious effects of CRi and MRD were independent. In this large CIBMTR cohort, survival outcomes differ among AML patients based on depth of CR and presence of MRD at the time of alloHCT. Further studies should focus on optimizing post-alloHCT outcomes for patients with responses less than CR.

Risk factors of BK viral hemorrhagic cystitis in allogenic hematopoietic stem cell transplantation.

Reactivation of BK virus (BKV) can occur during intensive immunosuppression such as in allogenic hematopoietic stem cell transplant (AHSCT) recipients for whom a systematic PCR urine test for BKV will be positive in 50% to 100% of patients. Only 5% to 40% will develop BKV hemorrhagic cystitis (HC). Thus, BKV PCR testing is useful to confirm a diagnosis of BKV-HC but not to predict its occurrence. The aim of this retrospective study was to ascertain the risk factors of developing BKV HC, mostly in patients receiving posttransplant cyclophosphamide. The study looked at data from Grenoble Alpes University Hospital included in the national retrospective register ProMISe, administered by the "Société Francophone de Greffe de Moelle et de Thérapie Cellulaire". Urine BKV PCR was performed when patients presented grade ≥ 2 hematuria with clinical symptoms of cystitis. BKV-HC was defined as an association of clinical symptoms of cystitis, grade ≥ 2 hematuria and BKV viruria > 7 log10 copies/ml. From January 2014 to January 2018, 168 AHSCTs were considered for analysis, of which 43 (25.6%) developed BKV-HC and 44.9% of the subgroup that received posttransplant cyclophosphamide. After logistic regression, the risk factors associated with BKV-HC were reduced to posttransplantation exposure to cyclophosphamide (OR 4.25, [1.66; 10.87], P = .02), age < 40 y (OR 3.85 [1.51; 9.80], P = .005) and corticosteroid therapy (OR 3.86, [1.59; 9.36], P = .003). Exposure to cyclophosphamide, younger age (<40) and corticosteroid therapy are potential risk factors for BKV-HC.

Conventional chemotherapy for acute myeloid leukemia in older adults: Impact on nutritional, cognitive, and functional status.

OBJECTIVES: The impact of conventional treatment for acute myeloid leukemia (AML) on the nutritional, cognitive, and functional status of elderly patients is seldom studied. This assessment was performed in the context of the LAMSA 2007 trial. METHODS: The trial enrolled 424 patients with de novo AML. Among them, 316 benefited from geriatric assessment (GA) including nutritional, cognitive, and functional status and were scored according to Eastern Cooperative Oncology Group (ECOG) and sorror for the prediction of treatment toxicity, morbidity, and mortality. Patients were investigated at diagnosis for three times during follow-up. RESULTS: This study showed that AML and its treatment have no impact on cognitive (P = .554) nor functional status (P = .842 for Activity of Daily Living and P = .087 for Instrumental Activities of Daily Living). The nutritional status improved over time (P = .041). None of these three parameters at baseline, associated or not with ECOG and sorror scores, impacted survivals or toxicities. CONCLUSIONS: The cognitive, functional, and nutritional status had no impact in this cohort of fit elderly AML patients without unfavorable cytogenetics. The GA tools used provided no additional information compared with ECOG and sorror scores, to predict toxicity, morbidity, or mortality due to intensive chemotherapy.

Impact of early candidemia on the long-term outcome of allogeneic hematopoietic stem cell transplant in non-leukemic patients: an outcome analysis on behalf of IDWP-EBMT.

We assessed the incidence and outcome of early candidemia after hematopoietic stem cell transplant (HSCT). The analysis included all first HSCTs performed from 2000 to 2015 in adult and pediatric patients with a non-leukemic disease and recorded in the EBMT registry. Overall survival (OS), non-relapse mortality (NRM), and relapse mortality (RM) were evaluated. Candidemia was diagnosed in 420 of 49,852 patients at a median time of 17 days post HSCT (range 0-100), the cumulative incidence being 0.85%. In 65.5% of episodes, candidemia occurred by day 30 after HSCT. The mortality rate by day 7 was 6.2%, whereas 100-day NRM was higher (HR 3.47, p < 0.0001), and 100-day OS was lower (HR 3.22, p < 0.0001) than that of patients without candidemia. After a median follow-up of 4.3 years, 5-year OS, NRM, and RM for patients with and without candidemia were 50.5% vs. 60.8%, p < 0.0001, 28.2% vs.18.8%, p < 0.0001, and 25.3% vs. 27.2%, p = 0.4, respectively. In conclusion, in non-leukemic transplant patients, the occurrence of an early episode of candidemia is rare but it is still associated with a negative effect on the outcome.

Lomustine is beneficial to older AML with ELN2017 adverse risk profile and intermediate karyotype: a FILO study.

We previously reported the benefit of lomustine addition to conventional chemotherapy in older acute myeloid leukemias with nonadverse chromosomal aberrations in the LAM-SA 2007 randomized clinical trial (NCT00590837). A molecular analysis of 52 genes performed in 330 patients included in this trial, 163 patients being treated with lomustine in combination with idarubicin and cytarabine and 167 without lomustine, identified 1088 mutations with an average of 3.3 mutations per patient. NPM1, FLT3, and DNMT3A were the most frequently mutated genes. A putative therapeutic target was identified in 178 patients (54%). Among five molecular classifications analyzed, the ELN2017 risk classification has the stronger association with the clinical evolution. Patients not treated with lomustine have an expected survival prognosis in agreement with this classification regarding the overall and event-free survivals. In strong contrast, lomustine erased the ELN2017 classification prognosis. The benefit of lomustine in nonadverse chromosomal aberrations was restricted to patients with RUNX1, ASXL1, TP53, and FLT3-ITDhigh/NPM1WT mutations in contrast to the intermediate and favorable ELN2017 patients. This post-hoc analysis identified a subgroup of fit elderly AML patients with intermediate cytogenetics and molecular markers who may benefit from lomustine addition to intensive chemotherapy.

Myeloablative Conditioning for Allogeneic Transplantation Results in Superior Disease-Free Survival for Acute Myelogenous Leukemia and Myelodysplastic Syndromes with Low/Intermediate but not High Disease Risk Index: A Center for International Blood and Marrow Transplant Research Study.

Compared with reduced-intensity conditioning (RIC), myeloablative conditioning (MAC) is generally associated with lower relapse risk after allogeneic hematopoietic cell transplantation (HCT) for acute myelogenous leukemia (AML) and myelodysplastic syndromes (MDS). However, disease-specific risk factors in AML/MDS can further inform when MAC and RIC may yield differential outcomes. We analyzed HCT outcomes stratified by the Disease Risk Index (DRI) in 4387 adults (age 40 to 65 years) to identify the impact of conditioning intensity. In the low/intermediate-risk DRI cohort, RIC was associated with lower nonrelapse mortality (NRM) (hazard ratio [HR], .74; 95% confidence interval [CI], .62 to .88; P < .001) but significantly greater relapse risk (HR, 1.54; 95% CI, 1.35 to 1.76; P < .001) and thus inferior disease-free survival (DFS) (HR, 1.19; 95% CI, 1.07 to 1.33; P = .001). In the high/very high-risk DRI cohort, RIC was associated with marginally lower NRM (HR, .83; 95% CI, .68 to 1.00; P = .051) and significantly higher relapse risk (HR, 1.23; 95% CI, 1.08 to 1.41; P = .002), leading to similar DFS using either RIC or MAC. These data support MAC over RIC as the preferred conditioning intensity for patients with AML/MDS with low/intermediate-risk DRI, but with a similar benefit as RIC in high/very high-risk DRI. Novel MAC regimens with less toxicity could benefit all patients, but more potent antineoplastic approaches are needed for the high/very-high risk DRI group.

Comparison of outcomes of HCT in blast phase of BCR-ABL1- MPN with de novo AML and with AML following MDS.

Comparative outcomes of allogeneic hematopoietic cell transplantation (HCT) for BCR-ABL1- myeloproliferative neoplasms (MPNs) in blast phase (MPN-BP) vs de novo acute myeloid leukemia (AML), and AML with prior myelodysplastic syndromes (MDSs; post-MDS AML), are unknown. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we compared HCT outcomes in 177 MPN-BP patients with 4749 patients with de novo AML, and 1104 patients with post-MDS AML, using multivariate regression analysis in 2 separate comparisons. In a multivariate Cox model, no difference in overall survival (OS) or relapse was observed in patients with MPN-BP vs de novo AML with active leukemia at HCT. Patients with MPN-BP in remission had inferior OS in comparison with de novo AML in remission (hazard ratio [HR], 1.40 [95% confidence interval [CI], 1.12-1.76]) due to higher relapse rate (HR, 2.18 [95% CI, 1.69-2.80]). MPN-BP patients had inferior OS (HR, 1.19 [95% CI, 1.00-1.43]) and increased relapse (HR, 1.60 [95% CI, 1.31-1.96]) compared with post-MDS AML. Poor-risk cytogenetics were associated with increased relapse in both comparisons. Peripheral blood grafts were associated with decreased relapse in MPN-BP and post-MDS AML (HR, 0.70 [95% CI, 0.57-0.86]). Nonrelapse mortality (NRM) was similar between MPN-BP vs de novo AML, and MPN-BP vs post-MDS AML. Total-body irradiation-based myeloablative conditioning was associated with higher NRM in both comparisons. Survival of MPN-BP after HCT is inferior to de novo AML in remission and post-MDS AML due to increased relapse. Relapse-prevention strategies are required to optimize HCT outcomes in MPN-BP.

A Personalized Prediction Model for Outcomes after Allogeneic Hematopoietic Cell Transplant in Patients with Myelodysplastic Syndromes.

Allogeneic hematopoietic stem cell transplantation (HCT) remains the only potentially curative option for myelodysplastic syndromes (MDS). Mortality after HCT is high, with deaths related to relapse or transplant-related complications. Thus, identifying patients who may or may not benefit from HCT is clinically important. We identified 1514 patients with MDS enrolled in the Center for International Blood and Marrow Transplant Research Registry and had their peripheral blood samples sequenced for the presence of 129 commonly mutated genes in myeloid malignancies. A random survival forest algorithm was used to build the model, and the accuracy of the proposed model was assessed by concordance index. The median age of the entire cohort was 59 years. The most commonly mutated genes were ASXL1(20%), TP53 (19%), DNMT3A (15%), and TET2 (12%). The algorithm identified the following variables prior to HCT that impacted overall survival: age, TP53 mutations, absolute neutrophils count, cytogenetics per International Prognostic Scoring System-Revised, Karnofsky performance status, conditioning regimen, donor age, WBC count, hemoglobin, diagnosis of therapy-related MDS, peripheral blast percentage, mutations in RAS pathway, JAK2 mutation, number of mutations/sample, ZRSR2, and CUX1 mutations. Different variables impacted the risk of relapse post-transplant. The new model can provide survival probability at different time points that are specific (personalized) for a given patient based on the clinical and mutational variables that are listed above. The outcomes' probability at different time points may aid physicians and patients in their decision regarding HCT.

Reduced intensity conditioning for acute myeloid leukemia using melphalan- vs busulfan-based regimens: a CIBMTR report.

There is a lack of large comparative study on the outcomes of reduced intensity conditioning (RIC) in acute myeloid leukemia (AML) transplantation using fludarabine/busulfan (FB) and fludarabine/melphalan (FM) regimens. Adult AML patients from Center for International Blood and Marrow Transplant Research who received first RIC allo-transplant between 2001 and 2015 were studied. Patients were excluded if they received cord blood or identical twin transplant, total body irradiation in conditioning, or graft-versus-host disease (GVHD) prophylaxis with in vitro T-cell depletion. Primary outcome was overall survival (OS), secondary end points were leukemia-free survival (LFS), nonrelapse mortality (NRM), relapse, and GVHD. Multivariate survival model was used with adjustment for patient, leukemia, and transplant-related factors. A total of 622 patients received FM and 791 received FB RIC. Compared with FB, the FM group had fewer transplant in complete remission (CR), fewer matched sibling donors, and less usage of anti-thymocyte globulin or alemtuzumab. More patients in the FM group received marrow grafts and had transplantation before 2005. OS was significantly lower within the first 3 months posttransplant in the FM group (hazard ratio [HR] = 1.82, P < .001), but was marginally superior beyond 3 months (HR = 0.87, P = .05). LFS was better with FM compared with FB (HR = 0.89, P = .05). NRM was significantly increased in the FM group during the first 3 months of posttransplant (HR = 3.85, P < .001). Long-term relapse was lower with FM (HR = 0.65, P < .001). Analysis restricted to patients with CR showed comparable results. In conclusion, compared with FB, the FM RIC showed a marginally superior long-term OS and LFS and a lower relapse rate. A lower OS early posttransplant within 3 months was largely the result of a higher early NRM.

Risk Factors for Graft-versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation Using Post-Transplant Cyclophosphamide.

Post-transplant cyclophosphamide (PTCy) has significantly increased the successful use of haploidentical donors with a relatively low incidence of graft-versus-host disease (GVHD). Given its increasing use, we sought to determine risk factors for GVHD after haploidentical hematopoietic cell transplantation (haplo-HCT) using PTCy. Data from the Center for International Blood and Marrow Transplant Research on adult patients with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who underwent PTCy-based haplo-HCT (2013 to 2016) were analyzed and categorized into 4 groups based on myeloablative (MA) or reduced-intensity conditioning (RIC) and bone marrow (BM) or peripheral blood (PB) graft source. In total, 646 patients were identified (MA-BM = 79, MA-PB = 183, RIC-BM = 192, RIC-PB = 192). The incidence of grade 2 to 4 acute GVHD at 6 months was highest in MA-PB (44%), followed by RIC-PB (36%), MA-BM (36%), and RIC-BM (30%) (P = .002). The incidence of chronic GVHD at 1 year was 40%, 34%, 24%, and 20%, respectively (P < .001). In multivariable analysis, there was no impact of stem cell source or conditioning regimen on grade 2 to 4 acute GVHD; however, older donor age (30 to 49 versus <29 years) was significantly associated with higher rates of grade 2 to 4 acute GVHD (hazard ratio [HR], 1.53; 95% confidence interval [CI], 1.11 to 2.12; P = .01). In contrast, PB compared to BM as a stem cell source was a significant risk factor for the development of chronic GVHD (HR, 1.70; 95% CI, 1.11 to 2.62; P = .01) in the RIC setting. There were no differences in relapse or overall survival between groups. Donor age and graft source are risk factors for acute and chronic GVHD, respectively, after PTCy-based haplo-HCT. Our results indicate that in RIC haplo-HCT, the risk of chronic GVHD is higher with PB stem cells, without any difference in relapse or overall survival.