David Valcárcel

Sustained Remissions of High-Risk Acute Myeloid Leukemia and Myelodysplastic Syndrome After Reduced- Intensity Conditioning Allogeneic Hematopoietic Transplantation: Chronic Graft-Versus-Host Disease Is the Strongest Factor Improving Survival

PURPOSE Reduced-intensity conditioning (RIC) for allogeneic stem-cell transplantation (allo-SCT) reduces nonrelapse mortality (NRM). This reduction makes it possible for patients who are ineligible for high-dose myeloablative conditioning allo-SCT to benefit from graft-versus-leukemia reaction. In this multicenter, prospective study of patients with acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS), we investigated the efficacy of RIC allo-SCT from a human leukocyte antigen-identical sibling by using a regimen that uses fludarabine and busulfan. PATIENTS AND METHODS Ninety-three patients with AML (n = 59) and MDS (n = 34) were included, and the median age was of 53 years. Follow-up for survivors was 43 months (range, 3 to 89 months). The conditioning regimen consisted of fludarabine (150 mg/m(2)) and oral busulfan (8 to 10 mg/kg). All except one patient received mobilized peripheral blood stem cells. Graft-versus-host disease (GVHD) prophylaxis consisted of cyslosporine and methotrexate or mycophenolate mofetil. RESULTS The 100-day, 1-year, and 4-year incidences of NRM were 8, 16%, and 21%, respectively. The 1- and 4-year relapse cumulative incidences were 23% and 37%, respectively, and leukemia recurrence was the main cause of death. The 4-year disease-free survival (DFS) and overall survival (OS) rates were 43% and 45%, respectively. The 4-year cumulative incidence of chronic GVHD was 53% (45% extensive), and its development was the major factor associated with lower relapse incidence and improved DFS and OS. CONCLUSION Our results confirm the capacity of this RIC regimen to obtain long-term remissions in patients ineligible for a conventional allo-SCT. The results suggest an important role of the development of chronic GVHD in reducing relapse and improving DFS and OS.

Development and validation of a prognostic scoring system for patients with chronic myelomonocytic leukemia

The natural course of chronic myelomonocytic leukemia (CMML) is highly variable but a widely accepted prognostic scoring system for patients with CMML is not available. The main aim of this study was to develop a new CMML-specific prognostic scoring system (CPSS) in a large series of 558 patients with CMML (training cohort, Spanish Group of Myelodysplastic Syndromes) and to validate it in an independent series of 274 patients (validation cohort, Heinrich Heine University Hospital, Düsseldorf, Germany, and San Matteo Hospital, Pavia, Italy). The most relevant variables for overall survival (OS) and evolution to acute myeloblastic leukemia (AML) were FAB and WHO CMML subtypes, CMML-specific cytogenetic risk classification, and red blood cell (RBC) transfusion dependency. CPSS was able to segregate patients into 4 clearly different risk groups for OS (P < .001) and risk of AML evolution (P < .001) and its predictive capability was confirmed in the validation cohort. An alternative CPSS with hemoglobin instead of RBC transfusion dependency offered almost identical prognostic capability. This study confirms the prognostic impact of FAB and WHO subtypes, recognizes the importance of RBC transfusion dependency and cytogenetics, and offers a simple and powerful CPSS for accurately assessing prognosis and planning therapy in patients with CMML.

Mesenchymal stem cells expanded in vitro with human serum for the treatment of acute and chronic graft-versus-host disease: results of a phase I/II clinical trial

This trial evaluated the feasibility and efficacy of the infusion of mesenchymal stem cells expanded using human serum for the treatment of refractory acute or chronic graft-versus-host disease. Twenty-eight expansions were started. In 22, a minimum of more than 1x106 mesenchymal stem cells/kg were obtained after a median of 26 days; this threshold was not obtained in the remaining cases. Ten patients received cells for the treatment of refractory or relapsed acute graft-versus-host disease and 8 for chronic disease. One patient treated for acute graft-versus-host disease obtained a complete response, 6 had a partial response and 3 did not respond. One of the chronic patients achieved complete remision, 3 a partial response, and 4 did not respond. The current study supports the use of this approach in less heavily treated patients for both acute and chronic graft-versus-host disease. The trial has been registered at ClinicalTrials.gov: identifier NCT00447460.

Influence of the intensity of the conditioning regimen on the characteristics of acute and chronic graft‐versus‐host disease after allogeneic transplantation

The graft‐versus‐host disease (GVHD) characteristics of 150 consecutive patients undergoing reduced intensity conditioning allogeneic (allo‐RIC) transplants and 88 patients undergoing myeloablative conditioning regimen were analysed. All patients received the same GVHD prophylaxis and peripheral blood stem cells from a human leucocyte antigen identical sibling. The cumulative incidence of acute GVHD (aGVHD) was 67% and 44% in the myeloablative and allo‐RIC regimen groups, respectively (P < 0·001), and was 39% vs. 29%, respectively (P = 0·043), for grades 2–4 aGVHD. Only conditioning type (myeloablative versus allo‐RIC) significantly influenced the incidence of aGVHD in multivariate analysis: Hazard ratio (HR) = 2·16 [95% confidence interval (CI): 1·52–3·07], P < 0·0001. The cumulative incidence of chronic GVHD (cGVHD) was 63% and 71% among myeloablative and allo‐RIC patients respectively (P = 0·084). This trend was because of the higher incidence of limited cGVHD, but not extensive cGVHD among allo‐RIC recipients [HR = 3·3 (95% CI: 1·42–8·08), P = 0·0017]. Moreover, among patients who developed cGVHD, the cumulative incidence of limited cGVHD was significantly lower in the myeloablative group than in the allo‐RIC group (7% vs. 25%, P = 0·007). Duration of immunosuppression was shorter among allo‐RIC patients (35·5% vs. 68·8% required systemic immunosuppression 36 months after transplant, P = 0·028). Although prospective controlled trials are required to further evaluate the effect of the conditioning regimen on GVHD, our results suggest that RIC modifies the incidence and characteristics of both acute and cGVHD after allogeneic transplantation, and decreases the immunosuppression requirements in long‐term follow up when compared with myeloablative conditioning.

Chimerism analysis following allogeneic peripheral blood stem cell transplantation with reduced-intensity conditioning.

Summary:We have performed a prospective study to evaluate early chimerism and its kinetics after allogeneic peripheral blood stem cell transplantation among 68 patients who received a reduced-intensity conditioning (RIC) regimen with fludarabine plus melphalan (n=40) or busulphan (n=28). Chimerism was analyzed by polymerase chain reaction amplification of short tandem repeats in unfractionated (UF) and/or fractionated nucleated cells from bone marrow and peripheral blood (PB). All of the patients showed initial donor engraftment and no patient presented primary or secondary graft failure. In UF samples, the probability of achieving stable complete donor chimerism (CDC) in PB within the first 6 months was 70% on day +30, 85% on day +100 and 95% on day +180. CDC in granulocytes was observed in nearly all cases from day +30 onwards. CDC in T cells, however, differed among melphalan and busulphan recipients during the first 3 months (100 vs 0% on day +30 and 93 vs 20% on day +90, respectively). In multivariate analysis, the only significant variable associated with the achievement of early CDC was having received more than two lines of chemotherapy pretransplant (P<0.02). No correlation was found between the rate of achieving early CDC and the occurrence of acute graft-versus-host disease (GVHD) or disease progression post-transplant. In multivariate analysis, the only variable that influenced the incidence of disease progression post-transplant was the development of chronic extensive GVHD (P<0.05). In conclusion, a state of CDC is readily obtained within the first 6 months after our RIC protocols. Donor myeloid engraftment occurs rapidly in all cases, while early T-cell CDC is more common in more immunosuppressed hosts and, perhaps, in melphalan recipients.

Allogeneic hematopoietic SCT as treatment option for patients with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): a consensus conference proposal for a standardized approach.

Allogeneic hematopoietic SCT (HSCT) has been proposed as a treatment for patients with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). HSCT has been performed in nine patients using different protocols with varying success. Based on this preliminary experience, participants of the first consensus conference propose a common approach to allogeneic HSCT in MNGIE. Standardization of the transplant protocol and the clinical and biochemical assessments will allow evaluation of the safety and efficacy of HSCT as well as optimization of therapy for patients with MNGIE.

Conventional versus reduced-intensity conditioning regimen for allogeneic stem cell transplantation in patients with hematological malignancies

Abstract:  Background:  Allogeneic hematopoietic stem cell transplantation (HSCT) from human leukocyte antigen (HLA)‐compatible sibling donors is a potential curative treatment for hematological and non‐hematological malignancies. Nevertheless, high mortality rates may be associated with this therapy, especially in older patients, those with other comorbidities or who receive a second HSCT. Patients and methods: We analyzed the factors associated with transplant‐related mortality (TRM) and overall survival in 157 consecutive adult patients (104 males and 53 females) who received a HSCT [29 bone marrow (BM) transplantation and 128 peripheral blood (PB) transplantation] from a HLA‐identical sibling between January 1995 and March 2002 in our institution. One hundred patients received a standard conditioning prior to HSCT (STAND) and 57 patients received a reduced‐intensity conditioning (RIC) HSCT. Fifty‐eight patients were in an early phase at transplant and 99 in a non‐early phase. Median age was 46 yr (16–66), and 90 patients (57%) were >45 yr of age. Results: Patients in the RIC group were older than those in the STAND group, and had a higher proportion of non‐early disease phases including a prior autologous HSCT in 39%. Median follow‐up for survivors was 28 and 15 months in the STAND and RIC groups (P < 0,001), respectively. Cumulative incidence of TRM at 2 yr was 30% [95% confidence interval (CI) 22–41%] for the STAND group and 22% (95% CI 13–37%) for the RIC group [non‐significant (NS)]. Factors associated with a higher TRM in multivariate analysis were: STAND vs. RIC conditioning regimen [relative risk (RR) 5.4; 95% CI 2.3–12.8; P < 0.001]; age ≥45 yr vs. <45 yr (RR 5; 95% CI 2.4–10.8, P < 0.001); second vs. first HSCT (RR 2.8, 95% CI 1.3–6.3, P = 0.01) and non‐T‐cell‐depleted vs. T‐cell‐depleted graft (RR 2.7, 95% CI 1.3–5.8, P = 0.009). Overall survival (OS) at 2 yr was 52.5 ± 10.4% for STAND group and 59 ± 16.8% in RIC group. Factors associated with poorer OS in multivariate analysis were: STAND vs. RIC conditioning regimen (RR 3.4, 95% CI 1.7–6.9, P = 0.001); age ≥45 vs <45 yr (RR 2.5, 95% CI 1.4–4.5, P = 0.002) and diagnosis [other than chronic myeloid leukemia (CML) vs. CML] (RR 2.6, 95% CI 1.2–5.7 P = 0.02). Conclusions: Our results indicate that the introduction of RIC allogeneic HSCT for patients at high risk for TRM (advanced age, prior HSCT and non‐T‐cell depletion) leads to a reduction in the TRM and improvement in the OS.

The effect of immunoglobulin VH gene mutation status and other prognostic factors on the incidence of major infections in patients with chronic lymphocytic leukemia

Infections are a major factor in the clinical course of chronic lymphocytic leukemia (CLL) and account for 30% to 50% of all deaths. The pathogenesis of infections in CLL is related to hypo‐γ‐globulinemia, T‐cell immune dysfunction, and the immunosuppressive effect of treatment.

Comparison of Two Pretransplant Predictive Models and a Flexible HCT-CI Using Different Cut off Points to Determine Low-, Intermediate-, and High-Risk Groups: The Flexible HCT-CI Is the Best Predictor of NRM and OS in a Population of Patients Undergoing allo-RIC

Patient comorbidities are being increasingly analyzed as predictors for outcome after hematopoietic stem cell transplantation (HSCT), especially in allogeneic HSCT (Allo-HSCT). Researchers from Seattle have recently developed several pretransplant scoring systems (hematopoietic cell transplantation comorbidity index [HCT-CI] and the Pretransplantation Assessment of Mortality (PAM) model) from large sets of HSCT recipients with the aim of improving non-transplant models, mainly the Charlson Comorbidity Index (CCI). The validation of these comorbidity indexes in other institutions and in different disease and conditioning-related settings is of interest to determine whether these models are potentially applicable in clinical practice and in research settings. We performed a retrospective study in our institution including 194 consecutive reduced-intensity conditioning (RIC) AlloHSCT (allo-RIC) recipients to compare the predictive value of the PAM score, CCI, the original HCT-CI, and the flexible HCT-CI using a different risk group stratification. The median patient pretransplant scores for the HCT-CI, PAM, and CCI were 3.5, 22, and 0, respectively. The flexible HCT-CI risk-scoring system (restratified as: low risk [LR] 0-3 points, intermediate risk [IR] 4-5 points, and high risk [HR] >5 points) was the best predictor for non-relapse mortality (NRM). The 100-day and 2-year NRM incidence in these risk categories was 4% (95% confidence interval C.I. 2%-11%), 16% (95% C.I. 9%-31%), and 29% (95% C.I. 19%-45%), respectively (P < .001), and 19% (95% C.I. 12%-28%), 33% (95% C.I. 22%-49%), and 40% (95% C.I. 28%-56%), respectively (P=.01). However, we found no predictive value for NRM using neither the original HCT-CI nor the PAM or CCI models. The better predictive capacity for NRM of the flexible HCT-CI than PAM and CCI was confirmed with the c-statistics (c-statistics of 0.672, 0.634, and 0.595, respectively). Regarding the 2-year overall survival (OS), the flexible HCT-CI score categories were also associated with the highest predictive HR. In conclusion, our single-center study suggests that the flexible HCT-CI is a good predictor of 2-year NRM and survival after an allo-RIC.

Comparable non-relapse mortality and survival after HLA-identical sibling blood stem cell transplantation with reduced or conventional-intensity preparative regimens for high-risk myelodysplasia or acute myeloid leukemia in first remission

We prospectively compared two strategies of allogeneic PBSCT from HLA-identical siblings in adults with poor-risk AML or myelodysplastic syndrome with >5% marrow blasts in an early disease status (AML or refractory anemia with excess blasts (RAEB type 2) in first remission after chemotherapy or untreated RAEB type 1). Based only on age, all consecutive patients were offered one of two specific transplant protocols. Patients ⩽50 years old received conventional high-dose conditioning with cyclophosphamide-TBI and use of CD34+-selected PBSCT (CTCD34+ group), while patients aged >50 years received a reduced-intensity conditioning (RIC) with fludarabine and oral busulphan (FB-RIC). Seventy-five patients entered the study (35 in the CTCD34+ and 39 in the FB-RIC group). The median follow-up was >4 years in both groups. The 4-year non-relapse mortality (NRM) was 19 and 20%, respectively (P=0.8). Relapse and survival were also equivalent in both groups. These results suggest that in this setting, the expected high NRM in elderly patients can be reduced with an RIC regimen.