Effect of Conditioning Regimen Intensity on Acute Myeloid Leukemia Outcomes after Umbilical Cord Blood Transplantation

Reduced-intensity conditioning (RIC) umbilical cord blood (UCB) transplantation is increasingly used in hematopoietic stem cell transplantation (HCT) for older and medically unfit patients. Data on the efficacy of HCT after RIC relative to myeloablative conditioning (MAC) are limited. We compared the outcomes of acute myeloid leukemia (AML) patients >18 yrs who received UCB grafts after either RIC or MAC. One hundred nineteen adult patients with AML in complete remission (CR) underwent an UCB transplant after RIC (n =74, 62%) or MAC (n = 45, 38%) between January 2001 and December 2009. Conditioning was either reduced intensity and consisted of cyclophosphamide 50 mg/kg, fludarabine 200 mg/m2, and total-body irradiation (TBI) 200 cGy or myelablative and consisted for cyclophosphamide 120 mg/kg, fludarabine 75 mg/m2, and TBI 1200-1320 cGy. All patients received cyclosporine (day −3 to day +180) and mycophenolate mofetil (day −3 to day +45) post-HCT immunosuppression and hematopoietic growth factor. Use of RIC was reserved for patients >45 years (n = 66, 89%) or preexisting severe comorbidities (n = 8, 11%). The 2 groups were similar except for preceding myelodysplastic syndrome (RIC = 28% versus MAC = 4%, P < .01) and age that was dictated by the treatment protocols (median, RIC = 55 years versus MAC = 33years; P < .01). The incidence of neutrophil recovery at day +42 was higher with RIC (94% versus MAC = 82%, P < .1), whereas platelet recovery at the sixth month was similar (RIC = 68% versus MAC = 67%, P = .30). Incidence of grade II-IV acute graft-versus-host disease (aGVHD) (RIC = 47% versus MAC = 67%, P < .01) was decreased with similar incidence of chronic GVHD (cGVHD) (RIC = 30% versus MAC = 34%, P = .43). Median follow-up for survivors was 3.8 and 4.5 years for RIC and MAC, respectively (P = .4). Using RIC, 3-year leukemia-free survival (LFS) was decreased (31% versus MAC = 55%, P = .02) and 3-year relapse incidence was increased (43% versus MAC = 9%, P < .01). Two-year transplant-related mortality (TRM) was similar (RIC = 19% versus MAC = 27%; P = .55). In multivariate analysis, RIC recipients and those in CR2 with CR1 duration <1 year had higher risk of relapse and poorer LFS with no independent predictors of TRM. UCB with RIC extends the use of allogeneic HCT for older and frail patients without excessive TRM with greater benefit for patients in CR1 and CR2 with longer CR1

Does the Hematopoietic Cell Transplantation Specific Comorbidity Index Predict Transplant Outcomes? A Validation Study in a Large Cohort of Umbilical Cord Blood and Matched Related Donor Transplants

AbstractThe hematopoietic cell transplantation specific comorbidity index (HCT-CI) has been recently proposed to predict the probability of nonrelapse mortality (NRM) and overall survival (OS) in allogeneic HCT recipients while taking into account any pretransplant comorbidity. We tested the validity of the HCT-CI in a cohort of 373 adult HCT recipients (184 matched-related donor and 189 unrelated umbilical cord blood) who received a myeloablative (N = 150) or nonmyeloablative (N = 223) conditioning regimen. HCT-CI scores of 0, 1, 2, and ≥3 were present in 58 (16%), 56 (15%), 64 (17%), and 195 (52%) patients, respectively. Pulmonary conditions were the most common comorbidity. Cumulative incidence of NRM at 2 years was 10%, 20%, 24%, and 28% for HCT-CI scores of 0, 1, 2, and ≥3, respectively (P = .01). The corresponding probability of OS at 2 years was 72%, 67%, 51%, and 48%, respectively (P < .01). On multivariate analyses adjusted for recipient age, disease risk, donor source, and conditioning regimen intensity, the relative risks for NRM for HCT-CI scores of 1, 2, and ≥3 (compared to a score of 0) were 2.0 (95% confidence intervals, 0.8–5.3), 2.6 (1.0–6.7), and 3.2 (1.4-7.4), respectively. The risks for overall mortality were 1.2 (0.6-2.1), 2.0 (1.1-3.4), and 2.1 (1.3-3.3), respectively. In subgroup analyses, the HCT-CI score did not consistently predict NRM and OS among different donor sources and conditioning regimens. The HCT-CI, although a useful tool for capturing pretransplant comorbidity and risk-assessment, needs to be further validated prior to adopting it for routine clinical use

Monosomal Karyotype at the Time of Diagnosis or Transplantation Predicts Outcomes of Allogeneic Hematopoietic Cell Transplantation in Myelodysplastic Syndrome

AbstractVarious cytogenetic risk scoring systems may determine prognosis for patients with myelodysplastic syndromes (MDS). We evaluated 4 different risk scoring systems in predicting outcome after allogeneic hematopoietic cell transplantation (alloHCT). We classified 124 patients with MDS using the International Prognostic Scoring System (IPSS), the revised International Prognostic Scoring System (R-IPSS), Armand's transplantation-specific cytogenetic grouping, and monosomal karyotype (MK) both at the time of diagnosis and at alloHCT. After adjusting for other important factors, MK at diagnosis (compared with no MK) was associated with poor 3-year disease-free survival (DFS) (27% [95% confidence interval, 12% to 42%] versus 39% [95% confidence interval, 28% to 50%], P = .02) and overall survival (OS) (29% [95% confidence interval, 14% to 44%] versus 47% [95% confidence interval, 36% to 59%], P = .02). OS but not DFS was affected by MK at alloHCT. MK frequency was uncommon in low-score R-IPPS and IPSS. Although IPSS and R-IPSS discriminated good/very good groups from poor/very poor groups, patients with intermediate-risk scores had the worst outcomes and, therefore, these scores did not show a progressive linear discriminating trend. Cytogenetic risk score change between diagnosis and alloHCT was uncommon and did not influence OS. MK cytogenetics in MDS are associated with poor survival, suggesting the need for alternative or intensified approaches to their treatment

Minimal residual disease prior to allogeneic hematopoietic cell transplantation in acute myeloid leukemia: a meta-analysis

Minimal residual disease prior to allogeneic hematopoietic cell transplantation has been associated with increased risk of relapse and death in patients with acute myeloid leukemia, but detection methodologies and results vary widely. We performed a systematic review and meta-analysis evaluating the prognostic role of minimal residual disease detected by polymerase chain reaction or multiparametric flow cytometry before transplant. We identified 19 articles published between January 2005 and June 2016 and extracted hazard ratios for leukemia-free survival, overall survival, and cumulative incidences of relapse and non-relapse mortality. Pre-transplant minimal residual disease was associated with worse leukemia-free survival (HR=2.76 [1.90-4.00]), overall survival (HR=2.36 [1.73-3.22]), and cumulative incidence of relapse (HR=3.65 [2.53-5.27]), but not non-relapse mortality (HR=1.12 [0.81-1.55]). These associations held regardless of detection method, conditioning intensity, and patient age. Adverse cytogenetics was not an independent risk factor for death or relapse. There was more heterogeneity among studies using flow cytometry-based than WT1 polymerase chain reaction-based detection (I(2)=75.1% vs. <0.1% for leukemia-free survival, 67.8% vs. <0.1% for overall survival, and 22.1% vs. <0.1% for cumulative incidence of relapse). These results demonstrate a strong relationship between pre-transplant minimal residual disease and post-transplant relapse and survival. Outcome heterogeneity among studies using flow-based methods may underscore site-specific methodological differences or differences in test performance and interpretation

Circulating Angiogenic Factors Associated with Response and Survival in Patients with Acute Graft-versus-Host Disease: Results from Blood and Marrow Transplant Clinical Trials Network 0302 and 0802

AbstractCirculating angiogenic factors (AF) reflect tissue healing capacity, although some AF can also contribute to inflammation and are indicative of endothelial dysfunction. The AF milieu in acute graft-versus-host disease (aGVHD) has not been broadly characterized. We hypothesized that patients with abundant AF involved in repair/regeneration versus those mediating damage/inflammation would have improved outcomes. Circulating AF known predominantly for repair/regeneration (epidermal growth factor [EGF], fibroblast growth factor-1 and -2, heparin binding–EGF–like growth factor, and vascular endothelial growth factor-A [VEGF-A], -C, and -D) and for damage/inflammation (angiopoietin-2, endothelin-1, soluble endoglin [sEng], follistatin [FS], leptin, and placental growth factor [PlGF]) were measured in a discovery set of hematopoietic cell recipients with grade III and IV aGVHD and compared with controls, then validated in 2 aGVHD cohorts enrolled in Blood and Marrow Transplant Clinical Trials Network (BMT CTN) trials 0302 (n = 105, serum) and 0802 (n = 158, plasma) versus controls without aGVHD (n = 53, serum). Levels of EGF and VEGF-A were lower than in controls at the onset of aGVHD in both trials and higher with complete response to first-line aGVHD therapy in CTN 0802. FS and PlGF were elevated in aGVHD measured in either serum or plasma. At day 28 after initial aGVHD therapy, elevated FS was an independent negative prognostic factor for survival in both cohorts (hazard ratio, 9.3 in CTN 0302; 2.8 in CTN 0802). These data suggest that circulating AF are associated with clinical outcomes after aGVHD and, thus, may contribute to both pathogenesis and recovery