Autologous and allogeneic stem cell transplantation for myelodysplastic syndrome

Comparative assessment of conventional chromosomal analysis and fluorescence in situ hybridization in the evaluation of suspected myelodysplastic syndromes: A single institution experience

Background:

Myelodysplastic syndromes (MDSs) are a heterogeneous group of clonal hematopoietic neoplasms, roughly half of which harbor cytogenetic abnormalities with diagnostic, prognostic, and therapeutic significance. Fluorescence in situ hybridization (FISH) for the most commonly seen abnormalities (5/5q, –7/7q, +8, and –20/20q–) is routinely performed alongside conventional cytogenetics (CC) in the evaluation of suspected MDS despite conflicting reports of its relative contribution compared to CC alone.

Objectives:

To assess the additional diagnostic and prognostic value of performing concurrent FISH versus CC alone in cases of suspected MDS.

Materials and Methods:

A total of 127 bone marrow samples submitted to our cytogenetic laboratory with a presumptive diagnosis of MDS were evaluated by concurrent CC and an MDS FISH panel.

Results:

CC was used as the gold standard method with 100% sensitivity in detecting suspected MDS-associated cytogenetic abnormalities. FISH alone had a sensitivity of 76%, whereas CC alone achieved a sensitivity of 97%. The addition of FISH did not change the diagnosis nor change the Revised International Prognostic Scoring System score in any patient. Moreover, in 12 cases identified as positive by both CC and FISH, CC identified multiple chromosomal aberrations of clinical significance not interrogated by the FISH probe panel.

Conclusion:

CC alone is sufficiently sensitive in detecting suspected MDS-associated cytogenetic abnormalities that influence clinical decision-making. Routine FISH testing does not provide a significant increase in test sensitivity when an adequate karyotype is obtained. Therefore, FISH testing is best reserved for suspected MDS cases lacking sufficient metaphases.

[Myelodysplastic syndrome in the elderly: comprehensive geriatric assessment and therapeutic recommendations]

The onset of myelodysplastic syndromes (MDS) is usually around the age of 70. Despite this, most clinical trials are restricted to younger subjects. Thus, the management of elderly patients with MDS is not always optimal. Physiologically, elderly patients show characteristics that differ from those of younger patients and that condition their pharmacological treatment. In this regard, the comprehensive geriatric assessment (CGA) becomes particularly important. This document gathers conclusions from the 1(st) Meeting of Members of the Sociedad Española de Medicina Geriátrica and the Sociedad Española de Hematología y Hemoterapia, with the objective of proposing the establishment of CGA instruments to assist in the decision-making process of elderly patients with MDS. The results of this consensus document will focus on the diagnosis, prognosis, treatment and management of adverse events in this age group.

Myelodysplastic syndromes/neoplasms: recent classification system based on World Health Organization Classification of Tumors - International Agency for Research on Cancer for Hematopoietic and Lymphoid Tissues

The myelodysplastic Syndromes (MDS) are a group of clonal hematopoietic stem cell diseases characterized by cytopenia(s), dysplasia in one or more of the major myeloid cell lines, ineffective hematopoiesis, and increased risk of development of acute myeloid leukemia. The classification and the diagnostic criteria have been redefined by the recent World Health Organization Classification of Tumors – International Agency for Research on Cancer for Hematopoietic and Lymphoid Tissues. The myelodysplastic syndromes are now classified into the following categories – refractory cytopenia with unilineage dysplasia, refractory anemia with ring sideroblasts, refractory cytopenia with multilineage dysplasia, refractory anemia with excess blasts, myelodysplastic syndrome associated with isolated del (5q), myelodysplastic syndrome – unclassifiable, and childhood myelodysplastic syndrome. The clinicopathologic features, morphology, differential diagnosis, immunophenotyping, cytogenetics, prognosis and predictive factors are presented in the light of recent World Health Organization Classification of Tumors – International Agency for Research on Cancer.

Hematopoietic stem cell transplantation for MDS

Hematopoietic stem cell transplantation (HSCT) offers potentially curative therapy for patients with myelodysplastic syndromes (MDS). However, as the majority of patients with MDS are in the seventh or eighth decade of life, conventional transplant regimens have been used only infrequently, and only with the development of reduced-intensity conditioning has transplantation been applied more broadly to older patients. Dependent upon disease status at the time of transplantation, 30% to 70% of patients can be expected to be cured of their disease and survive long term. However, posttransplant relapse and graft-versus-host disease (GVHD) remain problems and further investigations are needed.

A pilot study of bendamustine in elderly patients with high-risk MDS and AML

We examined the efficacy of bendamustine in 15 pretreated patients (12 men, 3 women, median age 69 years) with acute myeloid leukaemia (AML) or myelodysplastic syndromes (MDS) 3 AML, 5 sAML, 5 CMML II, 1 RAEB II. Patients belonged to the following cytogenetic groups: 3 complex abnormal karyotypes, 7 normal karyotypes, 1 case with 20q- as sole anomaly and 4 single aberrations. The patients received in median two cycles of bendamustine (range 1-5) with a dose of 100 mg/m(2) at Day 1 + 2 (repeated after 28 days). Nine of 15 patients had no side effects of the treatment, six patients suffered from vomiting and epigastric pain as adverse effects of bendamustine. According to the IWG criteria, no complete remission or reduction of transfusions frequency have been observed. Three patients showed no response, one patient with AML died due to progressive disease. In 11 of 12 patients with initial leukocytosis (median 68,975 microl(-1), range 24,000-149,000 microl(-1)), a significant reduction of leukocytosis was achieved with bendamustine with a median duration of 4 weeks. In summary, treatment with bendamustine in patients with high-risk MDS or sAML with leukocytosis can result in a significant reduction of leukocytes, but fails to achieve hematological responses or improvement of transfusions dependency.

Accurate detection of uniparental disomy and microdeletions by SNP array analysis in myelodysplastic syndromes with normal cytogenetics

Progress in the management of patients with myelodysplastic syndromes (MDS) has been hampered by the inability to detect cytogenetic abnormalities in 40-60% of cases. We prospectively analyzed matched pairs of bone marrow and buccal cell (normal) DNA samples from 51 MDS patients by single nucleotide polymorphism (SNP) arrays, and identified somatically acquired clonal genomic abnormalities in 21 patients (41%). Among the 33 patients with normal bone marrow cell karyotypes, five (15%) had clonal, somatically acquired aberrations by SNP array analysis, including four with segmental uniparental disomies (UPD) and one with three separate microdeletions. Each abnormality was detected more readily in CD34+ cells then in unselected bone marrow cells. Paired analysis of bone marrow and buccal cell DNA from each patient was necessary to distinguish true clonal genomic abnormalities from inherited copy number variations and regions with apparent LOH. UPDs affecting chromosome 7q were identified in two patients who had a rapidly deteriorating clinical course despite a low-risk International Prognostic Scoring System score (IPSS). Further studies of larger numbers of patients will be needed to determine whether 7q UPD detected by SNP array analysis will identify higher-risk MDS patients at diagnosis, analogous to those with 7q cytogenetic abnormalities.

Myelodysplastic syndromes: biology and treatment

Optimal management of patients with myelodysplastic syndromes (MDS) requires an insight into the biology of the disease and the mechanisms of action of the available therapies. This review focuses on low-risk MDS, for which chronic anaemia and eventual progression to acute myeloid leukaemia are the main concerns. We cover the updated World Health Organization classification, the latest prognostic scoring system, and describe novel findings in the pathogenesis of 5q- syndrome. We perform in depth analyses of two of the most widely used treatments, erythropoietin and lenalidomide, discussing mechanisms of action, reasons for treatment failure and influence on survival.

Transplantation in remission improves the disease-free survival of patients with advanced myelodysplastic syndromes treated with myeloablative T cell-depleted stem cell transplants from HLA-identical siblings

From 1985 to 2004, 49 patients with advanced myelodysplastic syndromes (MDS) (> or =5% blasts) or acute myeloid leukemia (AML) transformed from MDS underwent T cell depleted bone marrow or peripheral blood hematopoietic stem cell transplantation (HSCT) from HLA-identical siblings following conditioning with a myeloablative regimen that included total body irradiation (44 patients) or busulfan (5 patients). Thirty-six patients received chemotherapy (3 low dose and 33 induction doses) before conditioning, and 13 patients did not receive any chemotherapy. Prior to transplantation, 22 of the 36 treated patients were in hematologic remission; 4 were in a second refractory cytopenia phase (26 responders); 8 had failed to achieve remission; and 2 of the responders had progression or relapse of their MDS (10 failures). No post-transplantation pharmacologic prophylaxis for graft-versus-host disease (GVHD) was given. The median age was 48 yrs (range 13-61). Forty-five of the 49 patients engrafted; 2 had primary graft failure; and 2 died before engraftment. Only 3 patients developed acute GVHD (aGVHD) (grades I and III) and 1 chronic GVHD (cGVHD). At 3 yrs post-transplantation, the overall survival (OS) was 54% in the responders; 31% in the untreated group; and 0% in the failure group (P=.0004). The disease free survival (DFS) was 50%, 15% and 0% in each group respectively (P=.0008). In multivariate analysis, disease status before cytoreduction remained highly correlated with DFS (P<.001). The cumulative incidence (CI) of relapse at 2-yrs post-transplantation for the responders was 23%; for the untreated group was 38%; and for the failures was 50%. The CI of non-relapse mortality at 2-yrs post-transplantation, for the responders was 23%; for the untreated group was 38%; and for the failures was 40%. All survivors achieved a Karnofsky Performance Status (KPS) of > or =90. These results indicate that patients with advanced MDS who achieve and remain in remission or a second refractory cytopenia phase with chemotherapy before conditioning can achieve successful long-term remissions following a myeloablative T cell depleted allogeneic HSCT.

Allogeneic stem cell transplantation for myelodysplastic syndrome

Although it is only used to treat a minority of patients with myelodysplastic syndromes, stem cell transplantation (SCT) is the only proven curative treatment for this condition. Because MDS occurs in a population of older adults with significant comorbidities, reduced-intensity conditioning (RIC) regimens have been particularly important in extending safe SCT to the large MDS population over the age of 60 years. Extension of the unrelated donor pool together with the introduction of umbilical cord blood transplants in adults has extended the number of patients with suitable donors. Nevertheless overall mortality from SCT is greater than 50% because of relapse and non-relapse mortality (NRM). New developments to improve outcome include the tailoring of the transplant approach to the individual based on age and comorbidity, and the use of pretransplant chemotherapy to reduce disease bulk prior to transplant, as well as the introduction of post-transplant immunotherapy (pre-emptive donor lymphocyte infusions) and chemotherapy to prevent relapse. Further improvements in transplant outcome await better ways to reconstitute immunity and amplify the graft-versus-leukemia (GVL) effect without causing graft-versus-host disease (GVHD), as well as further extension of the donor pool and exploration of risk-adapted regimens for the population of MDS in their seventh to eighth decade.