Long term follow-up of Asian patients with chronic myeloid leukemia (CML) receiving allogeneic hematopoietic stem cell transplantation (HSCT) from HLA-identical sibling—evaluation of risks and benefits

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only known curative therapy for patients with chronic myeloid leukemia (CML), but is associated with significant morbidity and mortality. The recent introduction of imatinib mesylate (STI-571) and reduced intensity transplant regimens has made the choice of primary treatment for patients with CML increasingly difficult. We have evaluated the outcome of 53 patients who have received allogeneic HSCT from human leukocyte antigen (HLA)-identical sibling donors between October 1985 and March 2002, determined the variables affecting the outcome, and tried to define indications for this aggressive approach. Successful engraftment occurred in 49 (98%) of evaluable patients. Acute graft-versus-host disease (GVHD) of grade II to IV severity was observed in 63% of the evaluable patients whereas the incidence of chronic GVHD was 57.5%. The Kaplan-Meier estimate of survival at 10 years was 54% [95% confidence interval (CI): 38–70%] and 31% (95% CI: 6–56%) for patients with first chronic phase and more advanced diseases, respectively. Multivariate analysis showed that younger age, absence of grade III-IV GVHD, the use of busulphan and cyclophosphamide (BuCy) as preparative regimen, and transplantation performed after January 1992 were factors associated with improved survival. Patients who were 30 years of age or younger who had transplantation done within 1 year after diagnosis during their first chronic phase of disease had a particularly good prognosis, with a probability of surviving 10 years of 72% (95% CI: 52–92%). We conclude that allogeneic HSCT remains a feasible option for Asian patients with CML. The most favorable outcome is observed in younger patients with early phase of the disease.     

Haemopoietic stem cell transplantation--an evolving treatment for severe autoimmune and inflammatory diseases in rheumatology, neurology and gastroenterology

The concept of haemopoietic stem cell transplantation (HSCT) to treat severe autoimmune diseases has been around for several decades. Advances in the safety of HSCT have made it a clinical reality since 1995. Databases have registered around a thousand patients treated specifically for a wide range of diseases, predominantly multiple sclerosis (MS), systemic sclerosis (SSc), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Phase I/II prospective and retrospective studies have supported the potential of autologous HSCT as a treatment option in severely affected patients, with profound and prolonged clinical responses in some diseases, although procedures are generally not curative. Allogeneic HSCT appears to offer curative potential, but the potential of high toxicity has limited its use in this context. The exact role of HSCT remains to be defined, particularly in the context of other advances in the treatment of autoimmune disease. Along with other groups, the European Group for Blood and Marrow Transplantation (EBMT) are overseeing several phase III trials in autologous transplantation. Given the risks of the HSCT, eligibility is restricted to patients who have severe, treatment resistant disease, in whom the prognosis is otherwise poor. This review aims to summarise the current published data in this evolving treatment for relatively rare patients with resistant or rapidly progressive disease where treatment options are otherwise limited. This cross-fertilization of knowledge between many specialties may provide increasing therapeutic opportunities in otherwise untreatable diseases. Moreover, destroying and rebuilding immune systems may provide insights into autoimmune diseases.     

Curative options for sickle cell disease: haploidentical stem cell transplantation or gene therapy?

Haematopoietic stem cell transplantation (HSCT) is curative in sickle cell disease (SCD); however, the lack of available matched donors makes this therapy out of reach for the majority of patients with SCD. Alternative donor sources such as haploidentical HSCT expand the donor pool to nearly all patients with SCD, with recent data showing high overall survival, limited toxicities, and effective reduction in acute and chronic graft-versus-host disease (GVHD). Simultaneously, multiple gene therapy strategies are entering clinical trials with preliminary data showing their success, theoretically offering all patients yet another curative strategy without the morbidity and mortality of GVHD. As improvements are made for alternative donors in the allogeneic setting and as data emerge from gene therapy trials, the optimal curative strategy for any individual patient with SCD will be determined by many critical factors including efficacy, transplant morbidity and mortality, safety, patient disease status and preference, cost and applicability. Haploidentical may be the preferred choice now based mostly on availability of data; however, gene therapy is closing the gap and may ultimately prove to be the better option. Progress in both strategies, however, makes cure more attainable for the individual with SCD.     

Allogeneic hematopoietic stem cell transplantation for patients with chronic myeloid leukemia in second chronic phase attained by imatinib after onset of blast crisis

The prognosis for patients with chronic myeloid leukemia (CML) in blast crisis (BC) remains dismal even with the availability of the BCR-ABL tyrosine kinase inhibitor imatinib, since it only offers short-term benefit in most cases. Allogeneic hematopoietic stem cell transplantation (HSCT) seems to be a viable option for BC-CML patients who attained remission. We treated ten patients with ablative allogeneic HSCT, who achieved second chronic phase (CP) by the use of imatinib after onset of BC. Median patient age was 32 years (range 17–46). Among them, four patients received HSCT from human leukocyte antigen mismatched haplo-identical family donors. After a median follow-up of 24 months (range 8–42), six out of the ten patients were alive in durable complete cytogenetic remission, one patient died in relapse 4 months after transplantation, the others died of severe acute graft-versus-host disease and associated infections. No unusual organ toxicities and engraftment difficulties were observed. Extensive chronic GVHD developed in three of six patients who could be evaluated. Patients transplanted with haplo-identical donors had a high treatment-related modality. Allogeneic HSCT may represent a feasible treatment for patients with CML in second CP attained by imatinib after onset of BC especially when a suitable donor is available.     

Stem-cell transplantation in children and adults with sickle cell disease: an update

Sickle cell disease (SCD) is associated with significant morbidity, a decreased lifespan and a poor quality of life. While there is increasing evidence that hydroxyurea can improve the course of severe SCD, hematopoeitic stem-cell transplantation (HSCT) remains the only curative option for SCD. Multicenter trials have shown that HSCT after myeloablative conditioning has excellent outcomes in children with SCD, with an overall survival ranging from 93 to 97% and an event-free survival between 82 and 86%. With better understanding of the course of SCD in adulthood, there has been increasing interest in making HSCT a viable intervention in adults. Nonetheless, older patients with severe disease have not been considered suitable candidates because of the higher risks associated with myeloablative conditioning. Recently, reduced-intensity regimens have been used in adults with good results, albeit in a small number of patients. The main limitation of HSCT in both adults and children with SCD remains the lack of availability of fully matched HLA sibling donors for patients meeting transplant criteria.     

Successful engraftment and stable full donor chimerism after myeloablation with thiotepa,fludarabine, and melphalan and CD34-selected peripheral allogeneic stem cell transplantation in hemophagocytic lymphohistiocytosis

Allogeneic hematopoietic stem cell transplantation (HSCT) represents the only curative option for primary hemophagocytic lymphohistiocytosis (HLH), a rare disease of infants and young children, characterized by recurrent fever, hepatosplenomegaly, and cytopenia. We report a case of successful engraftment and stable full-donor chimerism in a patient with HLH who underwent peripheral allogeneic CD34-selected HSCT. The donor was his 1-antigen-HLA-mismatched grandmother. After a conditioning regimen based on the combination of thiotepa, fludarabine, melphalan, and rabbit antilymphocyte serum, the patient received a megadose of 26.3 x 10(6)/kg of CD34(+) peripheral blood cells. Neutrophil (>0.5 x 10(9)/L) and platelet (>50 x 10(9)/L) engraftment was observed on days +16 and +12, respectively, and the patient was discharged home on day +24. No acute or chronic GVHD was observed. Infectious complications were the main causes of re-hospitalization in the first year after transplantation, but no significant morbidity was observed thereafter. Thirty-two months after HSCT, the patient is alive and well, still in complete clinical remission of his underlying disease with a durable engraftment, normal NK activity and full donor chimerism. This case suggests that a fludarabine-based conditioning regimen and CD34-selected peripheral allogeneic HSCT may be a feasible option in case of unavailability of a fully HLA-matched related or unrelated donor.     

Availability of unrelated donors for hematopoietic stem cell transplantation for hemoglobinopathies

Hematopoietic stem cell transplantation (HSCT) is the only curative option for patients with hemoglobinopathies. However, fewer than 30% of individuals will have an HLA-identical sibling. Improvement in outcomes after HSCT using unrelated donors (URD), and the development of novel nontoxic preparative regimens may make URD HSCT an option for hemoglobinopathy patients who do not have an HLA-identical sibling donor. The National Marrow Donor Program (NMDP) maintains a Registry of 4 million volunteer donors, and facilitates URD HSCT for patients with life-threatening blood diseases. In light of the increased representation of minorities in the NMDP registry, donor searches were run in April 2001 for a cohort of 272 thalassemia patients and 77 sickle cell disease (SCD) patients for whom searches had been submitted between 1989 and 2001 in order to determine the current likelihood of finding a potential donor of hematopoietic stem cells for hemoglobinopathy patients. About 59.7% SCD patients 80.2% thalassemia patients will find at least one potential 6/6 HLA matched donor or umbilical cord blood (UCB) unit. All patients will find at least one donor or UCB that is a potential 5/6 HLA match. In conclusion the majority of hemoglobinopathy patients will find at least one potential HLA matched unrelated bone marrow donor or UCB.     

Comparison of non-myeloablative and reduced-intensity allogeneic stem cell transplantation in older patients with myelodysplastic syndromes

Allogeneic stem cell transplantation (HSCT) remains the only curative treatment for myelodysplastic syndromes (MDS) or myelodysplastic/myeloproliferative neoplasms (MDS/MPN) patients. The introduction of reduced intensity (RIC) and non-myeloablative (NMA) conditioning enabled HSCT in older or comorbid individuals representing the majority of patients. Studies comparing RIC and NMA conditioning are limited. We retrospectively analyzed 151 MDS or MDS/MPN patients older than 50 years who received NMA- or RIC-HSCT. Patients younger or older than 65 years at HSCT were analyzed separately. Patients receiving RIC-HSCT or NMA-HSCT were balanced in factors reflecting disease aggressiveness and the HCT-CI comorbidity score. The NMA conditioned patients had a higher incidence of graft rejection and chronic graft-vs-host disease. Cumulative incidence of relapse (CIR), non-relapse mortality (NRM) and overall survival (OS), did not differ significantly with regard to the conditioning regime in the whole cohort. In patients <65 years at HSCT, NMA conditioning associated with higher NRM and shorter OS by trend, while CIR was similar in both groups. In multivariable analyzes, the conditioning regimen remained a prognostic factor for NRM and OS in patients <65 years at HSCT. In MDS patients NMA and RIC conditioning result in similar disease control, but especially patients <65 years may benefit from RIC-HSCT.     

Hyperthyroidism After Allogeneic Hematopoietic Stem Cell Transplantation: A Report of Four Cases

Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for many hematological disorders, primary immunodeficiencies, and metabolic disorders. Thyroid dysfunction is one of the frequently seen complications of HSCT. However, hyperthyroidism due to Graves’ disease, autoimmune thyroiditis, and thyrotoxicosis are rare. Herein, we report a series of 4 patients who were euthyroid before HSCT but developed hyperthyroidism (3 of them developed autoimmune thyroid disease) after transplantation.     

Stem cell transplantation in patients with severe congenital neutropenia with evidence of leukemic transformation

Severe congenital neutropenia (SCN) is a hematologic condition characterized by arrested maturation of myelopoiesis at the promyelocyte stage of development. With appropriate treatment using recombinant human granulocyte-colony-stimulating factor (r-HuG-CSF), SCN patients are now surviving longer, but are at increased risk of developing myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML). Hematopoietic stem cell transplantation (HSCT) is the only curative option for these patients, but transplantation outcomes after malignant transformation are not well established. We report results for six patients with SCN who underwent HSCT for MDS or AML between 1997 and 2001 at two transplant centers. Two patients transplanted for MDS survived. Both of these patients were transplanted without being given induction chemotherapy. Four patients, who all received induction chemotherapy for AML prior to HSCT, died. Administering induction chemotherapy prior to HSCT resulted in significant morbidity. Rapid transplantation should be the goal for the SCN patient once the diagnosis of MDS/AML is established. SCN patients should be monitored carefully for progression to MDS in order to be treated with HSCT as soon as they have progressed and before developing AML. For SCN patients who progress to AML, HSCT should still be considered, even though the risks appear to be greater.     

Allogeneic transplantation for myelodysplastic syndrome (MDS)

Haematopoietic stem cell transplantation (HSCT) remains the only curative option for patients with myelodysplastic syndrome (MDS). Developing conditioning regimens with low toxicity, at the same time as preserving an effective graft versus tumour response, is pivotal to expanding the scope for allogeneic transplantation in older patients with MDS. With the introduction of reduced intensity conditioned regimens, transplant centres worldwide are able to offer allogeneic HSCT to a much larger cohort of patients. Graft versus host disease (GvHD) remains a significant cause of morbidity and mortality, however with the use of T-cell depletion, centres have been able to utilise volunteer unrelated donors with an increasing degree of HLA disparity. The graft versus dysplasia effect resulting from allogeneic HSCT and the infusion of donor leukocytes has led to a greater understanding of the immunological mechanisms that govern outcome following transplantation in MDS.     

(90)Y-ibritumomab tiuxetan followed by reduced-intensity conditioning and allo-SCT in patients with advanced follicular lymphoma

Reduced-intensity conditioning (RIC) hematopoietic SCT (HSCT) is a potentially curative therapeutic option for patients with advanced follicular lymphoma (FL), but disease relapse remains the most common cause of failure. Radioimmunoconjugates administered before RIC allo-HSCT may enhance cytoreduction and allow more time for GVL effect to develop without the associated toxicity of a myeloablative HSCT. We performed a retrospective study to describe the outcomes of patients with relapsed, refractory or transformed FL who received yttrium-90 ((90)Y)-ibritumomab tiuxetan followed by fludarabine and low-dose BU RIC allogeneic HSCT at the Dana-Farber Cancer Institute between 2006 and 2009, inclusively. Twelve patients were identified with a median age of 55 (40-66) years and a median number of lines of therapy of 5 (2-10). Two patients (17%) had transformed to a more aggressive histology and five (42%) had chemorefractory FL. Cumulative incidences of grade II-IV acute GVHD at 100 days were 17% (±11%) and chronic GVHD at 12 months were 63% (±19%). Two-year non-relapse mortality was 18% (±12%). Two-year OS and PFS were 83% (±11%) and 74% (±13%), respectively. This treatment is associated with favorable outcomes including acceptable rates of GVHD and relapse in advanced FL patients, and warrants prospective studies.     

Haematopoietic stem cell transplantation for sickle cell disease – current practice and new approaches

Sickle cell disease is an inherited disorder that affects over 5 million people worldwide. Current maintenance therapy has been successful in reducing complications and enhancing life expectancy; yet subclinical complications persist. To date, allogeneic haematopoietic stem cell transplant (HSCT) remains the only available curative therapy for sickle cell disease. With declining incidences of rejection and transplant‐ related mortality, disease‐free survival after human leucocyte antigen‐identical sibling transplant exceeds 90%. However, the majority of individuals with sickle cell disease do not have an human leucocyte antigen (HLA)‐identical sibling; therefore, research is expanding to focus on new approaches to alternative donor transplant. Advances in supportive care and conditioning regimens have led to expansion of the pool of donors to unrelated donors and haploidentical donors. Challenges remain in improving the safety and efficacy of HSCT from alternate donors. Early results from gene therapy may provide another curative option in patients with sickle cell disease. These approaches show early promise, but larger, longitudinal studies are needed to better determine the optimal clinical circumstances for transplant in sickle cell disease.     

Stem cell transplantation in hemoglobinopathies

beta-Thalassemia (thal) and sickle cell disease are the most common genetic diseases worldwide. Although supportive therapies such as regular transfusion and chelation for beta-thal and hydroxyurea (HU) for sickle cell disease have significantly improved clinical manifestations and the quality of life, they cannot eliminate disease and therapy-related complications. Today, hematopoietic stem cell transplantation (HSCT) is the only curative treatment for patients with hemoglobinopathies. The first successful HSCT was reported in 1981. At that time, more than 1,000 patients underwent HSCT in Pesaro, Italy. Sixty beta-thal patients underwent HSCT at the Department of Pediatric Hematology-Oncology, Akdeniz University School of Medicine, Antalya, Turkey between 1998 and 2006. We found stable mixed chimerism in 14 patients out of 45 (31%) in our transplanted thalassemia patients. The thalassemia free survival and overall survival rates were found to be 84.0 and 91.0%, respectively. The literature and our results indicate that HSCT can offer a cure for hemoglobinopathy patients.     

Reduced intensity conditioning in unrelated donor transplantation for refractory cytopenia in childhood

Myelodysplastic syndromes (MDS) are a heterogenous group of acquired hematopoietic stem cell disorders. Refractory cytopenia (RC) is the most common subtype of childhood MDS and hematopoietic stem cell transplantation (HSCT) is the only curative treatment. HSCT following a myeloablative preparative regimen is associated with a low probability of relapse and considerable transplant-related mortality. In the present European Working Groups of MDS pilot study, we investigated whether a reduced intensity conditioning regimen (RIC) is able to offer reduced toxicity without increased rates of graft failure or relapse. Nineteen children with RC were transplanted from an unrelated donor following RIC consisting of fludarabine, thiotepa and anti-thymocyte globulin. Three patients experienced graft failure. Neutrophil and platelet engraftment occurred at a median time of 23 and 30 days, respectively. Cumulative incidence of grade II-IV and grade III and IV acute graft-versus-host disease (GVHD) was 0.48 and 0.13, respectively; three patients developed extensive chronic GVHD. Although infections were the predominant complications, only one patient with extensive chronic GVHD died from infectious complications. Overall and event-free survival at 3 years were 0.84 and 0.74, respectively. In conclusion, our results were comparable to those of patients treated with myeloablative HSCT. Long-term follow-up is needed to demonstrate the expected reduction in long-term sequelae.     

Retrospective study of allogeneic haematopoietic stem-cell transplantation for myelofibrosis

Allogeneic haematopoietic stem-cell transplantation (HSCT) is the only curative treatment for myelofibrosis. We retrospectively analyzed the outcome of patients who underwent allogeneic HSCT, 1994-2008, and the potential risk factors affecting non-relapse mortality (NRM), OS and relapse-free survival (RFS). A total of 39 patients, 15-65 (median 49) years old, diagnosed with primary (n=27) or secondary (n=12) myelofibrosis underwent HSCT (25 related and 14 unrelated). In ten patients, disease had transformed into acute leukaemia. Lille prognosis score was low for 9, intermediate for 16 and high for 14 patients. The conditioning regimen was myeloablative (MAC) for 15 and reduced-intensity (RIC) fludarabine-based for 24, with successful engraftment in 38 patients. A total of 31 patients developed grade I-IV GvHD; 19 developed chronic GvHD. The 3-year OS, RFS and NRM rates (95% confidence interval) were 60% (42-74), 54% (37-59) and 30% (30-45), respectively.     

Mesenchymal stromal cells for steroid-refractory acute graft-versus-host disease: a report of two cases

Severe graft-versus-host disease (GVHD) is a lethal complication of allogeneic hematopoietic stem cell transplantation (HSCT). However, there have been only a few limited therapeutic options for the treatment of GVHD. Here we have reported two cases of the patients with acute steroid-refractory GVHD who underwent allogeneic HSCT. These patients received infusions of third-party clonal mesenchymal stem cells (cMSCs), which were isolated by a subfractionation culturing method (SCM) developed recently by our group, and showed marked improvement of the disease. MSCs represent a new potential therapeutic option in the treatment of steroid-refractory acute GVHD. They showed safety and improved clinical findings of the acute GVHD patients. However, further investigations are needed to understand the accurate mechanisms of MSCs and larger well-designed human clinical trials are necessary to prove further the safety and efficacy of the cMSCs for the treatment of acute GVHD patients.     

Adult Idiopathic Thrombocytopenic Purpura

The therapeutic options for the indolent non-Hodgkin's lymphomas have evolved significantly over the years. However, at present, allogeneic haematopoietic stem cell transplantation (HSCT), despite its significant transplant associated complications, is still the only option which may be delivered with curative potential. The debut of reduced-intensity conditioning regimens has extended the applicability of allogeneic transplants to groups of patients ineligible for conventional myeloablative allografts. However, there are still substantial hurdles to overcome, namely that of relapse, graft-versus-host disease and infection. Whilst follow-up is still relatively limited for a disease group with a median survival of up to 10 years, early results are extremely encouraging and further studies are warranted.     

Long-term health-related outcomes in survivors of childhood cancer treated with HSCT versus conventional therapy: a report from the Bone Marrow Transplant Survivor Study (BMTSS) and Childhood Cancer Survivor Study (CCSS)

HSCT is being increasingly offered as a curative option for children with hematologic malignancies. Although survival has improved, the long-term morbidity ascribed to the HSCT procedure is not known. We compared the risk of chronic health conditions and adverse health among children with cancer treated with HSCT with survivors treated conventionally, as well as with sibling controls. HSCT survivors were drawn from BMTSS (N = 145), whereas conventionally treated survivors (N = 7207) and siblings (N = 4020) were drawn from CCSS. Self-reported chronic conditions were graded with CTCAEv3.0. Fifty-nine percent of HSCT survivors reported ≥ 2 conditions, and 25.5% reported severe/life-threatening conditions. HSCT survivors were more likely than sibling controls to have severe/life-threatening (relative risk [RR] = 8.1, P < .01) and 2 or more (RR = 5.7, P < .01) conditions, as well as functional impairment (RR = 7.7, P < .01) and activity limitation (RR = 6.3, P < .01). More importantly, compared with CCSS survivors, BMTSS survivors demonstrated significantly elevated risks (severe/life-threatening conditions: RR = 3.9, P < .01; multiple conditions: RR = 2.6, P < .01; functional impairment: RR = 3.5, P < .01; activity limitation: RR = 5.8, P < .01). Unrelated donor HSCT recipients were at greatest risk. Childhood HSCT survivors carry a significantly greater burden of morbidity not only compared with noncancer populations but also compared with conventionally treated cancer patients, providing evidence for close monitoring of this high-risk population.     

Drug treatment is superior to allografting as first-line therapy in chronic myeloid leukemia

Early allogeneic hematopoietic stem cell transplantation (HSCT) has been proposed as primary treatment modality for patients with chronic myeloid leukemia (CML). This concept has been challenged by transplantation mortality and improved drug therapy. In a randomized study, primary HSCT and best available drug treatment (IFN based) were compared in newly diagnosed chronic phase CML patients. Assignment to treatment strategy was by genetic randomization according to availability of a matched related donor. Evaluation followed the intention-to-treat principle. Six hundred and twenty one patients with chronic phase CML were stratified for eligibility for HSCT. Three hundred and fifty four patients (62% male; median age, 40 years; range, 11-59 years) were eligible and randomized. One hundred and thirty five patients (38%) had a matched related donor, of whom 123 (91%) received a transplant within a median of 10 months (range, 2-106 months) from diagnosis. Two hundred and nineteen patients (62%) had no related donor and received best available drug treatment. With an observation time up to 11.2 years (median, 8.9 years), survival was superior for patients with drug treatment (P = .049), superiority being most pronounced in low-risk patients (P = .032). The general recommendation of HSCT as first-line treatment option in chronic phase CML can no longer be maintained. It should be replaced by a trial with modern drug treatment first.