Myelodysplastic syndromes

The trajectory of prognostication and risk stratification for patients with myelodysplastic syndromes

ABSTRACT

Risk stratification and prognostication are crucial for the appropriate management of patients with myelodysplastic syndromes (MDSs) or myelodysplastic neoplasms, for whom the expected survival can vary from a few months to >10 years. For the past 5 decades, patients with MDS have been classified into higher-risk vs lower-risk disease phenotypes using sequentially developed clinical prognostic scoring systems. Factors such as morphologic dysplasia, clinical hematologic parameters, cytogenetics, and, more recently, mutational information have been captured in prognostic scoring systems that refine risk stratification and guide therapeutic management in patients with MDS. This review describes the progressive evolution and improvement of these systems which has led to the current Molecular International Prognostic Scoring System.

Trends of classification, incidence, mortality, and survival of MDS patients in Switzerland between 2001 and 2012

Myelodysplastic syndromes (MDS) are emerging disorders of the elderly with an increasing burden on healthcare systems. He we report on the first population-based, epidemiological analysis of patients diagnosed with MDS in Switzerland between 2001 and 2012. The aim of this study was to characterize the extent and limitations of currently available population-based, epidemiological data and formulate recommendations for future health services research. The investigated outcomes comprised trends of annual case frequency, classification of morphological subtypes, incidence, mortality and survival. Annual case frequency increased by 20% (from 263 to 315 cases per year), whereas age-standardized incidence-/mortality-rates remained stable (2.5/1.1 per 100'000 person-years). This observation reflects population growth as well as higher diagnostic awareness and not an increase of age-specific risk. However, it will inevitably influence the future prevalence of MDS and the impact on healthcare systems. Reporting of classification in MDS subtypes was poor with modest improvement from 20% to 39% and increased awareness for mainly higher-risk diseases. Relative survival for all patients at 5-years (RS) ranged between 37 and 40%. Significant better RS was found for younger compared to older higher-risk MDS patients (48% vs. 17%), reflecting the effect of allogeneic hematopoietic stem-cell transplantation. However, no survival advantage was found in elderly patients after introduction of hypomethylating agents as standard for care in this patient group. Our data is in line with results from other MDS and cancer registries. It allows formulating recommendations for future collaborative health services research on MDS patients with national and international partners.

The revolution of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are clonal disorders of the hematopoietic system with resultant cytopenias and shortened survival. Better recognition of MDS and an aging population, some of whom have been treated with chemotherapy and radiation therapy for other cancers, is largely responsible for the growing incidence of this malignancy, which is divided into lower- and higher-risk subtypes. Erythropoiesis-stimulating agents are the first-line treatment options for patients with lower-risk MDS and symptomatic anemia or for those requiring transfusion support. Lenalidomide has been successfully used for patients with the del(5q) chromosomal abnormality who are also transfusion dependent. Hypomethylating agents, such as azacitidine and decitabine, are indicated for patients with higher-risk disease, with azacitidine demonstrating a survival advantage. Hematopoietic stem cell transplantation (HSCT) is a curative therapeutic approach available to less than 5% of patients with MDS. Combination therapies and newer single agents targeting the important cellular pathways are being explored for treatment of MDS with promising results.

Myelodysplastic syndromes: incidence and survival in the United States

BACKGROUND

Myelodysplastic syndromes (MDS) became reportable to the Surveillance, Epidemiology, and End Results (SEER) Program (the United States cancer surveillance program) in 2001. This provided the first opportunity to examine the incidence and survival of patients with MDS in the United States using a large, population-based database.

METHODS

The SEER 17 regions public-use database (November 2005 submission) was accessed to obtain data on the frequency, incidence, and survival of patients with MDS. Geographic areas were selected for inclusion in the SEER Program based on their ability to operate and maintain a high-quality, population-based cancer reporting system and for their epidemiologically significant population subgroups.

RESULTS

SEER data from 2001 through 2003 indicated that the risk of MDS increased with age, and approximately 86% of MDS cases were diagnosed in individuals aged > or =60 years (median age at diagnosis = 76 years). Men had a significantly higher incidence rate than women (4.5 vs 2.7 per 100,000 per year). Among racial groups, white individuals had the highest incidence rate. In 2003, approximately 10,300 incident cases of MDS were diagnosed in the United States. The survival of MDS patients was poor, with an observed 3-year survival rate of only 35% (5-year survival data were not available at the time of the current report). Male patients and patients who were diagnosed at an older age had significantly worse survival. MDS survival also varied by clinical subtype, and the survival of patients who had refractory anemia was somewhat worse than reported previously. The availability of descriptive epidemiologic data on MDS can be used now to facilitate much needed research on the etiology and outcome of MDS.

CONCLUSIONS

The current results indicated that >10,000 incident cases of MDS are diagnosed annually in the United States, and the survival of patients with MDS is poor. The availability of descriptive epidemiologic data on MDS can be used now to facilitate much needed research on the etiology and outcomes of MDS.

Telomere length changes after umbilical cord blood transplant

BACKGROUND

The establishment of donor-derived hematopoiesis in the recipients of hematopoietic stem cell (HSC) transplants involves extensive proliferation and differentiation of HSCs. Data from long-term survivors of HSC transplants suggest that these transplanted HSCs may experience a debilitating replicative senescence. A significant posttransplant shortening of peripheral blood mononuclear cell (PBMNC) telomeres has been observed in both marrow transplant and peripheral blood progenitor cell transplant recipients. Similar studies have not been performed for umbilical cord blood (UCB) HSC transplants, which might be expected to exhibit increased posttransplant replicative potential due to their inherently greater telomere length.

STUDY DESIGN AND METHODS

Blood was obtained from donor-recipient pairs of allogeneic PBHSC transplant and UCB HSC transplant, both before transplant and at follow-up treatments (minimum 1 year after transplant) after engraftment. Telomere restriction fragment length (TRFL) analysis was performed on the blood samples. The mean TRFL and posttransplant changes in the mean TRFL were analyzed.

RESULTS

Measurements of telomere lengths in the PBMNCs of transplant patients revealed a significant net decrease in telomere length in all transplant recipients compared with their respective donors. Our results also revealed that the PBMNCs of umbilical cord stem cell transplant patients retain a significantly longer posttransplant telomere length.

CONCLUSION

The significantly longer telomeres observed in the allogeneic UCB HSC transplant recipients compared to the allogeneic PBHSC transplant recipients in our study may be indicative of a replicative advantage inherent in the use of UCB HSC for transplant.

Autologous and allogeneic stem cell transplantation for myelodysplastic syndrome

Allogeneic stem cell transplantation (alloSCT) is the treatment of choice in the majority of young patients with advanced stages MDS if they have a suitable donor. Since outcome of transplantation is superior for patients with a low blast percentage, this supports the use of chemotherapy prior to transplantation in patients with high blast marrow infiltration. The allogeneic transplant procedure continues to carry a high treatment-related risk, but results have improved progressively over the years. The transplantation results using phenotypically matched voluntary unrelated donors have improved impressingly, mainly due to significantly reduced transplantation-related mortality rate. The upper age limit for transplantation has moved to 65-70 years after the introduction of reduced intensity conditioning regimens (RIC). The place of RIC remains to be determined also in older patients in view of the associated higher relapse risk. For patients lacking a suitable donor the choice is ambiguous. Although the number of reports on autologous stem cell transplantation is still limited, the outcome seems similar to allogeneicSCT with donors other than HLA-identical siblings. Further development of accurate prognostic classification systems will allow a risk-adapted strategy for an individual patient.

The impact of intensive antileukaemic treatment strategies on prognosis of myelodysplastic syndrome patients aged less than 61 years according to International Prognostic Scoring System risk groups

The present study applied the International Prognostic Scoring System (IPSS) to 306 consecutive myelodysplastic syndrome (MDS) patients diagnosed between August 1977 and September 2000 at the University Medical Centre Nijmegen. The aim was to investigate whether the IPSS could be used as a prognostic tool in MDS patients aged less than 61 years who were treated with acute myeloid leukaemia (AML)-like chemotherapy with or without transplantation, and whether the scoring system discriminated between the subgroups of patients who benefit from intensive treatment strategies. The patients were retrospectively assigned to the IPSS risk categories and compared with the IPSS workshop patients. Eighty-three of 159 patients aged < 61 years, classified as intermediate 1, intermediate 2 and high risk according to the IPSS, received intensive treatment consisting of chemotherapy only (n = 30), chemotherapy followed by either autologous stem cell transplantation (n = 7) or allogeneic stem cell transplantation (n = 46). After intensive treatment, the median survival was 2.6 years for the intermediate 1 risk group (n = 33), 3.4 years for the intermediate 2 risk group (n = 27) and 0.9 years for the high-risk group (n = 23). We conclude that the IPSS is an improved scoring system for patients receiving supportive care. Nevertheless, the scoring system does not seem to be the best method for predicting outcome after intensive antileukaemic treatment. In particular, intermediate 2 risk patients may benefit from intensive treatment.

Configuration of the TP53 gene as an independent prognostic parameter of myelodysplastic syndrome

Myelodysplastic syndrome (MDS) consists of a heterogeneous group of acquired hematopoietic stem cell disorders, characterized by bone marrow failure and leukemic transformation. Since hematological manifestations and clinical outcomes vary widely among MDS patients, a considerable number of studies have tried to identify the prognostic parameters for the stratification of patients into different risk groups. Based on reported risk-based studies, the International Prognostic Scoring System (IPSS) was proposed as a reliable risk assessment method for primary MDS patients, and several validating studies have clarified its usefulness. Critical prognostic parameters of the IPSS consist of chromosome findings, the percentage of marrow blasts, and the number of peripheral blood cytopenias. Although other laboratory findings, including several molecular alterations, have been identified as convincing prognostic factors in MDS, these molecular configurations were not selected as prognostic parameters in the IPSS, because analysis for these alterations were not routinely available for the management of patients with MDS. Because recent advances in molecular genetics may make it available as a routine work-up of MDS in the future, we discuss potential improvement of the IPSS by the addition of molecular analysis to the system, with particular reference to the configuration of the TP53 gene.

Isolation and therapeutic potential of human haemopoietic stem cells

The haemopoietic stem cell (HSC) has long been regarded as an archetypal, tissue specific, stem cell, capable of completely regenerating haemopoiesis after myeloablation. It has proved relatively easy to harvest HSC, from bone marrow or peripheral blood. In turn, isolation of these cells has allowed therapeutic stem cell transplantation protocols to be developed, that capitalise on their prodigious self renewal and proliferative capabilities. Ex vivo approaches have been described to isolate, genetically manipulateand expand pluripotent stem cell subsets. These techniques have been crucial to the development of gene therapy, and may allow adults to enjoy the potential advantages of cord blood transplantation. Recently, huge conceptual changes have occurred in stem cell biology. In particular, the dogma that, in adults, stem cells are exclusively tissue restricted has been questioned and there is great excitement surrounding the potential plasticity of these cells, with the profound implications that this has, for developing novel cellular therapies. Mesenchymal stem cells, multipotent adult progenitor cells and embryonic stem cells are potential sources of cells for transplantation purposes. These cells may be directed toproduce HSC, in vitro and in the future may be used for therapeutic, or drug development, purposes.

High-dose chemotherapy in high-risk myelodysplastic syndrome: covariate-adjusted comparison of five regimens

BACKGROUND

Antileukemic chemotherapy has been used for two decades to treat high-risk myelodysplastic syndrome (refractory anemia with excess of blasts [RAEB] and RAEB in transformation into acute leukemia [RAEB-t]) patients. Because the results of standard regimens have been disappointing, high-dose chemotherapeutic regimens were investigated recently. In the absence of randomized trials, the relative merits of various treatment regimens are unknown.

METHODS

The authors analyzed the outcome for 394 newly diagnosed patients treated between 1991 and 1999 with five regimens consisting of intermediate- or high-dose cytosine arabinoside (A) in combination with idarubicin (I), and introduced cyclophosphamide (C) and the new agents fludarabine (F) and topotecan (T) into new combinations with A. In addition to defining the role of high-intensity chemotherapy in the overall outcome for patients with RAEB-t and RAEB, the authors determined the relative merits of the five regimens (IA, FA, FAI, TA, and CAT), accounting for the nonrandom distribution of the prognostic covariates.

RESULTS

The overall complete response (CR) rate of 58% was significantly associated with karyotype, performance status (PS), treatment in the laminar air flow room, duration of antecedent hematologic disorder and age, but not French-American-British or International Prognostic Scoring System risk categories. Multivariate analysis did not identify statistically significant differences in CR rates obtained with each regimen. Induction death rates increased with age with all but the TA regimen; they were lowest with TA (5.4%) and highest with FAI (20.7%), and these differences were significant in patients older than 65 years. The trend for time to death was the same as for time to recurrence in all groups. Multivariate analysis of time to death identified treatment regimen (FA, FAI, and CAT), cytogenetic status (-5/-7), increasing age, and PS greater than 2 as significant independent unfavorable prognostic factors. After prognostic variables were accounted for, survival with IA treatment remained superior to that of FA and FAI but comparable to TA, and CR duration was only marginally shorter with FA. Landmark analysis showed the overall survival of responders to be superior to that of nonresponders, the difference remaining significant after adjustment for prognostic covariates.

CONCLUSIONS

Although the newer regimens did not improve outcome, TA and CAT produced results comparable to those of IA and may be considered treatment alternatives. The TA regimen was particularly effective in RAEB patients and could be delivered safely, with low induction mortality. Our results indicated that although CR seemed associated with survival advantage, innovative post-remission managements represent a challenge because improvement in outcome is not likely to come from intensified therapy.

Intensive treatment strategies in patients with high-risk myelodysplastic syndrome and secondary acute myeloid leukemia

Stem cell transplantation may lead to prolonged disease-free survival in young patients with high-risk myelodysplastic syndrome (MDS) and secondary acute myeloid leukemia. About one-third of patients transplanted with an HLA-identical family donor will experience long-term disease-free survival. Outcome appears to be better for younger patients, patients with less advanced stages of MDS and treatment early in the course of the disease. The results of transplantation using partially matched family donors and phenotypically matched voluntary unrelated donors are still unsatisfactory, mainly due to significantly higher transplantation related mortality rate. For patients lacking a suitable sibling donor autologous stem cell transplantation may constitute an alternative. The presence of sufficient residual polyclonal stem cells and achieving a complete remission after chemotherapy forms a prerequisite for a successful transplantation. Further development of accurate prognostic classification systems will allow a risk-adapted strategy for an individual patient.

Familial myelodysplastic syndrome with early age of onset

A family is described in which three members, the propositus, his brother, and son, developed a myelodysplastic syndrome (MDS) at the ages of 52, 35, and 25, respectively. A fourth member, the paternal uncle of the propositus, was diagnosed with chronic lymphocytic leukemia. Two of the three affected Individuals had megaloblastoid marrows with recognizable bone marrow cytogenetic abnormalities and progressive, nonleukemic bone marrow failure. The propositus was unresponsive to G-CSF and eventually died of sepsis. The second affected family member died of bone marrow transplant complications. The third affected family member underwent bone marrow transplantation and is showing signs of graft survival despite minor complications. The affected members of this pedigree appear to represent a continuum in severity of disease and, therefore, pathogenesis. The pattern of inheritance and clinical progression of the disease suggest a genetic defect which may predispose individuals to the development of MDS.

Efficacy of N-acetylcysteine and all-trans retinoic acid in restoring in vitro effective hemopoiesis in myelodysplastic syndromes

We evaluated the in vitro effect on clonogenic potential (CFU-GM) and apoptosis in myelodysplastic syndromes (MDS) progenitors of an anti-oxidant (N-acetylcysteine, NAC) and/or a differentiating (all-trans retinoic acid, ATRA) agent. NAC significantly reduced apoptosis, both NAC and ATRA induced an increase in CFU-GM, but NAC seemed to be particularly effective in the high risk (HR) MDS. NAC + ATRA conferred a significant advantage in terms of CFU-GM with respect to NAC and ATRA alone. Tumor Necrosis Factor-alpha (TNF-alpha) levels decreased after incubation with NAC in the MDS samples. This study shows that ineffective hemopoiesis in MDS could benefit from both NAC and ATRA, suggesting that anti-oxidant treatment may play a role in guaranteeing MDS cell survival, predisposing them towards differentiation.

Evidence for a continuous decline in haemopoietic cell function from birth: application to evaluating bone marrow failure in children

There are considerable differences in haemopoietic activity between young children and adults on the one hand, and between adults and the elderly on the other. A fundamental unanswered question is whether these differences relate to discrete stages or are part of a continuous process. We have sought to define aspects of the haematological ageing process, and have found that results from children with bone marrow failure syndromes differ from age-matched reference values. Haemopoietic cells were obtained from umbilical cord blood, from blood and bone marrow of healthy individuals and from the blood of young patients with bone marrow failure syndromes. Clonogenic myeloid progenitors (CFU-GM) were grown in semi-solid medium to measure their frequency; the proliferative capacity of myeloid progenitors was measured by replating colonies and observing secondary colony formation. We found that the frequency of CFU-GM in normal marrow increased and their proliferative capacity decreased exponentially with age. The proliferative capacity of CFU-GM in normal blood also decreased exponentially with age. This relationship extrapolated back to the levels of proliferation measured for cord blood CFU-GM (age = 0). The proliferative capacities of CFU-GM from children with bone marrow failure syndromes were severely reduced compared with age-matched reference values. These results indicate that a decline in haemopoietic progenitor cell function begins at birth and continues throughout life. This decline may occur prematurely in childhood marrow failure syndromes with a predisposition to leukaemia.

Application of the International Prognostic Scoring System for myelodysplastic syndromes

BACKGROUND

In March 1997 an international workshop introduced a new International Prognostic Scoring System (IPSS) for MDS. The goal of the present study was to apply the IPSS to a large group of MDS patients from one centre and to compare it to the FAB-classification.

PATIENTS

One hundred eighty-four MDS patients were included on the basis of similar criteria as used by the workshop but some of them (30) received AML-type therapy.

RESULTS

The IPSS separated our patients into distinctive prognostic subgroups (P = 0.0001). Median survival was respectively 6.5, 2.6, 1.3 and 0.75 years for the low-risk (22% of patients), the intermediate-1-risk (INT-1) (46%), the intermediate-2-risk (INT-2) (25%) and the high-risk group (7%). The IPSS also discriminated within each of the FAB-categories: RA patients (58 patients) were present in low-risk, INT-1-risk and INT-2-risk subgroups, RARS patients (23) were separated into low-risk and INT-1-risk subgroups. RAEB patients (53) were distributed predominantly between INT-1-risk and INT-2-risk groups, RAEB-t patients (23) between INT-2-risk and high-risk subgroups. CMML patients (27) were present in the low-risk, the INT-1-risk and the INT-2-risk group.

CONCLUSIONS

Our results confirm the effectiveness of the IPSS in predicting clinical outcome in MDS patients and indicate that it is an improved method compared to the FAB-classification.

Quinine improves the results of intensive chemotherapy in myelodysplastic syndromes expressing P glycoprotein: results of a randomized study

Intensive chemotherapy produces a lower complete remission (CR) rate in the myelodysplastic syndromes (MDS) than in de novo acute myeloid leukaemia (AML), possibly due in part to a higher incidence of P glycoprotein (PGP) expression in MDS blast cells. We designed a randomized trial of intensive chemotherapy with or without quinine, an agent capable of reverting the multidrug resistance (mdr) phenotype, in patients aged < or = 65 years with high-risk MDS. Patients were randomized to receive mitoxantrone 12 mg/m2/d days 2-5 + AraC 1 g/m2/12 h days 1-5, with (Q+) or without (Q-) quinine (30 mg/kg/d). 131 patients were included. PGP expression analysis was successful in 91 patients. In the 42 PGP-positive cases, 13/25 (52%) patients in the Q+ group achieved CR, compared to 3/17 (18%) patients in the Q- group (P = 0.02) and median Kaplan-Meier survival was 13 months in the Q+ group, and 8 months in the Q- group (P = 0.01). No life-threatening toxicity was observed with quinine. In conclusion, the results of this randomized study show that quinine increases the CR rate and survival in PGP-positive MDS cases treated with intensive chemotherapy.

Risk factors and their relationship to prognosis in myelodysplastic syndromes

Recent efforts have been directed at improving the methodology for predicting clinical outcomes in patients with myelodysplastic syndromes (MDS). This review focuses on the development of a consensual, prognostic, risk-based analysis system generated by the International MDS Risk Analysis Workshop. In the workshop, cytogenetic, morphological, and clinical data were combined and collated from a relatively large group of patients with primary MDS. Critical prognostic variables were evaluated using the data set. Based on these findings, the International Prognostic Scoring System (IPSS) was developed, compared with other systems, and shown to provide more accurate prognoses regarding survival and evolution to acute myeloid leukemia in MDS patients. The improvement was due to several features of the workshop model: more refined cytogenetic categorization, inclusion of cytopenias, improved subdivision of marrow blast percentages, four subgroups defining outcome, and separate stratification for age. The IPSS should result in better-defined clinical outcomes in MDS and provide a framework for future studies determining the possible role of molecular determinants (e.g. oncogenes, tumor suppressor genes, cytokine expression and responsiveness) for evaluating prognoses. The IPSS will likely prove useful in the design and analysis of therapeutic trials in MDS as well as in patient management.

Accelerated telomere shortening in young recipients of allogeneic bone-marrow transplants

BACKGROUND

The establishment of donor-derived haemopoiesis in the recipients of allogeneic bone-marrow transplants (BMT) involves extensive proliferation of haemopoietic stem cells. The biological consequences of this replicative stress are ill defined, but any "ageing" effect would carry the risk of an increased frequency of clonal disorders during later life. We compared blood-cell mean telomere lengths in donor/recipient pairs.

METHODS

Mean telomere length was calculated by in-gel hybridisation to leucocyte DNA from 56 normal individuals aged 0-96 years, and from 14 consecutive BMT recipients (aged 2-14 years) plus their respective donors (aged 2-46 years). Engraftment was confirmed by variable numbers of tandem repeats (VNTR) or gender analysis.

FINDINGS

On average, blood-cell telomeres of transplant recipients were 0.4 kb (95% CI -0.2 to -0.6) shorter than those of their respective donors. This degree of telomere loss is equivalent to a median of 15 years' (range 0-40) ageing in the healthy controls.

INTERPRETATION

The kinetics of haemopoietic engraftment impose replicative stress on the haemopoietic stem cells, resulting in a pronounced ageing effect, which may be sufficient to accelerate the onset of clonal haemopoietic disorders usually associated with later life. Monitoring of haemopoietic status in BMT recipients as time since BMT increases will be important. Assessment of transplant protocols under development in terms of their effects on telomere shortening is also indicated.

International Scoring System for Evaluating Prognosis in Myelodysplastic Syndromes

Despite multiple disparate prognostic risk analysis systems for evaluating clinical outcome for patients with myelodysplastic syndrome (MDS), imprecision persists with such analyses. To attempt to improve on these systems, an International MDS Risk Analysis Workshop combined cytogenetic, morphological, and clinical data from seven large previously reported risk-based studies that had generated prognostic systems. A global analysis was performed on these patients, and critical prognostic variables were re-evaluated to generate a consensus prognostic system, particularly using a more refined bone marrow (BM) cytogenetic classification. Univariate analysis indicated that the major variables having an impact on disease outcome for evolution to acute myeloid leukemia were cytogenetic abnormalities, percentage of BM myeloblasts, and number of cytopenias; for survival, in addition to the above, variables also included age and gender. Cytogenetic subgroups of outcome were as follows: “good” outcomes were normal, −Y alone, del(5q) alone, del(20q) alone; “poor” outcomes were complex (ie, ≥3 abnormalities) or chromosome 7 anomalies; and “intermediate” outcomes were other abnormalities. Multivariate analysis combined these cytogenetic subgroups with percentage of BM blasts and number of cytopenias to generate a prognostic model. Weighting these variables by their statistical power separated patients into distinctive subgroups of risk for 25% of patients to undergo evolution to acute myeloid leukemia, with: low (31% of patients), 9.4 years; intermediate-1 (INT-1; 39%), 3.3 years; INT-2 (22%), 1.1 years; and high (8%), 0.2 year. These features also separated patients into similar distinctive risk groups for median survival: low, 5.7 years; INT-1, 3.5 years; INT-2, 1.2 years; and high, 0.4 year. Stratification for age further improved analysis of survival. Compared with prior risk-based classifications, this International Prognostic Scoring System provides an improved method for evaluating prognosis in MDS. This classification system should prove useful for more precise design and analysis of therapeutic trials in this disease.

Idiopathic macrocytic anaemia in the aged: molecular and cytogenetic findings

Macrocytosis in the elderly is often caused by abnormalities of haematological stem cell differentiation. In this study, a group of elderly patients was analysed for four molecular and cell biological parameters. The aim of the study was to screen elderly patients with idiopathic macrocytic anaemia or MDS for a set of alterations which are related to haematological dysplasia. The analyses used were: DNA-methylation at the calcitonin A gene 5'-area, NRAS point mutations at codons 12 and 13, in vitro colony formation of peripheral blood progenitor cells and cytogenetics of bone marrow cells. The results show that a significant portion of elderly patients with idiopathic macrocytosis have one or more of the abnormalities analysed. Hypermethylation of the calcitonin A gene 5'-area at the chromosome 11 band p15 is relatively common (7/15). Chromosomal aberrations (3/12) and NRAS oncogene point mutations (0/15) were rare findings. In vitro culture of erythroid progenitor cells was relatively frequently abnormal (7/15). Eight of our nine macrocytic patients who did not fulfill the FAB criteria for MDS had at least one of the alterations studied; this suggests that these patients might represent early phases of a stem cell disorder.

Epidemiological and etiological aspects of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are increasingly recognized as a cause of bone marrow failure, and are at least as frequent as acute myeloid leukemias. While the overall incidence is about 2-4/100,000/year, incidence figures rise steeply with age. Incidence rates of 20-30/100,000/year in persons over 70 demonstrate that MDS are among the most common hematological neoplasias in this age group. However, due to difficulties of diagnosis and classification, patient registration in population-based registers is far from complete. As a prerequisite for truly representative statistics, future revisions of disease classification systems must incorporate MDS as a separate group of disorders. The difficulties in conducting epidemiological studies also impede the identification of risk factors for the development of MDS. Current knowledge of occupational risk factors is also reviewed here. More rapid progress in our understanding of MDS may come from recent advances in methodology that have begun to shed some light on the cytogenetic and molecular aspects of leukemogenesis in general, and MDS in particular. Non-random chromosomal changes can be found in about 50% of cases at diagnosis, but they are probably late events in the evolution of MDS, reflecting the progressive genomic instability of the premalignant clone. Proto-oncogene mutations have also been suggested to be relevant to the pathogenesis of MDS, but longitudinal studies of point mutations of the N-ras proto-oncogene revealed that such events, although often associated with rapid deterioration and transformation to AML, also appear to be late events during the course of disease. Therefore, it remains a major challenge to identify those lesions that initiate the multistep development of preleukemia. As the incidence of MDS correlates strongly with age, it is reasonable to presume that age-dependent changes of the hematopoietic system may play a role in the initiation of MDS. Aging is probably associated with a compromised marrow reserve through reduction in the size of the stem cell pool. Through increased proliferative activity, the remaining stem cells may be particularly vulnerable to mutagenic insults. Immunological attack on stem cells, mitochondrial DNA mutations, and the regulatory influence of the hematopoietic microenvironment must also be considered as possibly contributing to the early stages of MDS.

Immunoglobulin and T-cell receptor delta gene rearrangements are rarely found in myelodysplastic syndromes in chronic phase

Clonality, in MDS, can only be assessed in patients with chromosomal rearrangements or in females heterozygote for X chromosome restricted polymorphisms. "Illegitimate" rearrangements of the immunoglobulin heavy chain (IgH) gene and incomplete rearrangements involving V delta 2 and D delta 3 segments of the T-cell receptor delta (TcR delta) gene are seen in some cases of AML, and AML post-SMD, and can be detected by a sensitive PCR method. In order to analyse clonality in additional cases in MDS, we looked for Ig H and TcR delta gene rearrangement by PCR in 95 cases of MDS. A rearrangement of the Ig H gene was seen in 2 of the 95 patients: in the circulating blood of 2 of the 36 cases of chronic myelomonocytic leukaemia (CMML) and in none of the marrow samples of the other 59 MDS. A rearrangement of the TcR delta gene (involving V delta 2 and D delta 3 segments) was seen in three cases (in the circulating blood of two other CMLL patients, and in the bone marrow of another MDS patient). Twenty-five of the 90 cases of MDS with negative PCR findings, in addition to the five cases with positive PCR findings underwent Southern blot analysis of Ig H and TcR delta genes, and PCR analysis of V delta 1 and J delta 1 segments of the TcR delta gene. Those examinations were normal in all the cases tested. In patients with positive PCR findings for Ig H or V delta 2 D delta 3 rearrangements, the proportion of rearranged cells was evaluated at 1-5% in four cases, and 5-10% in the remaining patient. Because the analysis was performed on total circulating leukocytes or total nucleated marrow cells, the nature of the clonal population in positive cases (lymphoid cells? myeloid cells? blasts?) could not be determined. From a practical point of view, Ig H and TcR delta gene rearrangements seem to very rare in MDS, and cannot be used as clonality markers in most cases.

Long-term survivors in myelodysplastic syndromes: a report on 63 cases and comparison with short and intermediate survivors

Sixty-three of 373 patients (17%) with de novo myelodysplastic syndrome (MDS) survived more than 5 yr (long survivors). At diagnosis, they usually had no or only moderate cytopenias; 63% of them had marrow blasts < 5%; only 1 patient had circulating blasts; 60% had refractory anaemia (RA) or refractory anaemia with ringed sideroblasts (RARS); 19% of the 43 patients who were karyotyped had an abnormal clone, and only 2 patients had complex cytogenetic findings. Only 4 of the 63 patients progressed to another FAB type within 5 yr of diagnosis, from RA to refractory anaemia with excess of blasts (RAEB) or chronic myelomonocytic leukaemia (CMML). After 5 yr, 9 patients showed progression (including progression to AML in 5 patients). The other patients remained stable (43 cases) or died from cytopenias or unrelated disorders (11 cases). Except for 3 patients who achieved prolonged complete remission with intensive chemotherapy, and possibly 3 patients who responded to low dose Ara C, prolonged survival seemed to result mainly from the low natural course of the disease. Although, as expected, significant differences for age, cytopenias, circulating and bone marrow blasts, and karyotype were seen between short (< 2 yr) and long (> 5 yr) very few significant differences were seen between intermediate and long survivors. These 2 subgroups only differed by significantly lower age and higher haemoglobin level in long survivors. Multivariate scoring systems (Bournemouth, Sanz's and Lille scores) proved of relatively limited value in differentiating them.(ABSTRACT TRUNCATED AT 250 WORDS)

Age-related incidence and other epidemiological aspects of myelodysplastic syndromes

Although most haematologists perceive a rising prevalence and incidence of myelodysplastic syndromes (MDS), reliable epidemiological data on these disorders are largely lacking. The bone marrow register of the University of Düsseldorf allowed us to assess among other epidemiological features the incidence of MDS, which was compared to that of acute myeloid leukaemia (AML). Among a total of 18,416 different patients registered between 1975 and 1990, 584 cases of MDS (3.2%) and 506 cases of AML (2.8%) were identified. Over the study period, the percentage of newly diagnosed MDS rose from 1.3% to 4.5%, while there was no upward trend for AML. Among all patients undergoing bone marrow biopsy, the proportion of those over 60 years of age increased from 41.9% in 1975 to 54.1% in 1990. We found a strong correlation between the proportion of elderly patients and the relative frequency of MDS diagnoses. Thirty-one patients (5.3%) were classified as a secondary MDS because of previous treatment with cytotoxic chemotherapy and/or irradiation for a variety of malignancies. Twelve patients were identified in whom occupational exposure to organic solvents could not be ruled out. For calculating age-specific incidence rates, the analysis was confined to the town district of Düsseldorf (575,000 inhabitants), because exact demographical data were available for this population. In the last quinquennium of the study period (1986-90), myelodysplastic syndromes were more frequent than AML in the age group 50-70 years (4.9 v 1.8/100,000/year). In patients over 70, the incidence of MDS was more than 3 times that of AML (22.8 v 6.7/100,000). In this group, men had a higher incidence of MDS (33.9/100,000) than women (18/100,000). Crude annual incidence (all age groups) was also higher for MDS (4.1/100,000) than for AML (2.1/100,000) in recent years. We conclude that MDS are relatively common haematological neoplasias. The rising incidence in recent years is probably not due to changes in aetiological factors, but may reflect increased awareness on the part of physicians and extended use of diagnostic procedures in elderly patients.

Trisomy 8 and 11 in refractory anemia with excess blasts in transformation (RAEB-T)

There are no specific chromosomal abnormalities associated with refractory anemia with excess blasts in transformation [RAEB-T]. An 80-year-old white male with RAEB-T was found to have trisomies of chromosomes 8 and 11, i.e., 48,XY,+8,+11. To our knowledge, this chromosomal abnormality in RAEB-T has not been previously reported.

Mastocytosis and co-existent non-Hodgkin's lymphoma and myeloproliferative disorders

Generalised mastocytosis is a rare condition characterised by the clinical features of the release of vasoactive peptides from tissue mast cells infiltrating in the reticuloendothelial tissues. The mast cell however appears to have its origin in the pluripotential bone marrow stem cell committed to a basophil and it is therefore not surprising that myeloproliferative and myelodysplastic disorders commonly co-exist or terminate the clinical phase of mastocytosis. Both abnormal proliferation and maturation of the myeloid committed cells are found. Non-Hodgkin's lymphoma can occur before and after mastocytosis becomes manifest. While this is statistically a random event the relationship between lymphokines and mast cell differentiation and proliferation raises the possibility of a benign reactive lymphoid event eventually becoming malignant.

Circulating CD34+ cells: an adverse prognostic factor in the myelodysplastic syndromes

As part of an epidemiological survey of myelodysplastic syndromes (MDS) in southern Tasmania, 62 MDS patients identified over a 2 year period were tested for the presence of CD34, the human progenitor cell antigen (HPCA), in their peripheral blood. The results were correlated with transformation to acute myeloid leukemia (AML) and patient survival, and CD34+ status was compared as a prognostic indicator with Bournemouth score, cytogenetics, and CFU-GM colony growth which were also assessed. Circulating CD34+ cells were found in 23 of the 62 MDS patients; 9 of the 23 patients with circulating CD34+ cells transformed to AML, as compared with none of the 39 CD34 negative patients (P less than 0.0001); and 11 of the 23 patients with circulating CD34+ cells were dead at the end of the 2 year period, as opposed to 6 of the 39 with no CD34+ cells (P less than 0.03). The Bournemouth score was also significantly associated with transformation to AML (P less than 0.0001) and poor survival (P less than 0.04). These were the only significant associations of the possible prognostic factors studied with either transformation or survival. In summary, the presence of circulating CD34+ cells was significantly associated with both progression to AML and poor survival and was found to be a better prognostic indicator than cytogenetics or CFU-GM colony growth.

Gene mutations in myelodysplasia

The myelodysplastic syndrome is a paradigm of human preleukaemia. Normal haemopoiesis is progressively displaced by an abnormal clone derived from a mutated stem cell. The initial mutation is unknown but its occurrence may be related to the overall load of random mutations which are a consequence of both intrinsic DNA defects and external mutagens. Evolution of the pathological population is marked by an increasing load of genetic lesions at the molecular and cytogenetic levels. Ras mutations can be detected in the blood of about 50% of MDS patients. Fms mutations are less common but these lesions can be found both in patients and in haematologically normal subjects who have previously received cytotoxic therapy suggesting that they can occur early in the preleukaemic process. Clonal haemopoiesis in the absence of either ras or fms mutations can occur in these subjects. The data suggest the inability of mutant ras or fms genes alone to produce observable preleukaemic changes but that subjects with these mutations may be predisposed to future MDS. Ras mutations are a common accompaniment of a wide variety of malignancies and experimental transfection of the mutant gene can induce a malignant phenotype in cultured cells. There are many possible mechanisms for this transformation which may be relevant in a clinical context. Experimentally observed effects include a direct influence on the cell cycle, the induction of drug resistance and the stimulation of autocrine growth factor production. It may eventually be possible to define which gene mutations are important in conferring a malignant state, which determine phenotype and which are of incidental significance.

Prognostic factors in adult de novo myelodysplastic syndromes treated by intensive chemotherapy

We treated 47 adult patients with de novo myelodysplastic syndrome (MDS) by an anthracycline-AraC regimen. Median age was 54, and M/F 1.3. At diagnosis, 26 patients had refractory anaemia with an excess of blasts in transformation (RAEB-T) three had refractory anaemia (RA), 11 had refractory anaemia with excessive blasts (RAEB) and seven had chronic myelomonocytic leukaemia (CMML). Treatment was started within 3 months of diagnosis in 30 patients, and after more than 3 months in the 17 remaining patients. At the onset of treatment, 16 patients had progressed to acute myeloid leukaemia (AML). Twenty-two patients (47%) reached complete remission (CR), 10 (21%) had hypoplastic death and 15 (32%) had resistant disease. Median actuarial disease-free interval was 11 months. Median actuarial survival was 14 months from diagnosis and 10 months from the onset of treatment. A significantly higher CR rate was found in patients with RAEB-T at diagnosis (69% v 19% in patients with other FAB subtypes: P = 0.008), and in patients treated within 3 months of diagnosis. Using multivariate analysis, RAEB-T at diagnosis emerged as the most powerful prognostic factor of CR achievement. Karyotype was the only significant prognostic factor of disease-free interval, with a median of 16.5 months in patients with normal karyotype versus 4 months in patients with normal findings (P = 0.018). A subgroup of 15 patients with RAEB-T at diagnosis and normal karyotype, who had a CR rate of 80% and a median actuarial disease-free interval of 18 months, could be identified. Our results confirm that, overall, intensive chemotherapy has limited efficacy in MDS, especially when compared with allogeneic bone marrow transplantation (BMT). Relatively favourable results were obtained in our patients with RAEB-T at diagnosis, however, particularly those with normal karyotype. In that subgroup, intensive chemotherapy may be recommended, especially before BMT, as a high risk of relapse after BMT in patients with RAEB-T allografted as first line therapy has been reported.

The myelodysplastic syndromes. Case report and review

The myelodysplastic syndromes are a heterogenous group of hematologic disorders of myeloid progenitor cells. Oral manifestations may be among the first signs and often reflect degrees of neutropenia or neutrophil dysfunction. A patient with persistent herpes labialis and severe oral mucosal ulceration in myelodysplastic syndrome is reported. The features of myelodysplasia are reviewed and their oral manifestations and significance to dental management outlined.

de novo myelodysplastic syndromes in adults aged 50 or less. A report on 37 cases

We report on 37 adults aged 50 years or less with de novo myelodysplastic syndrome (MDS) (excluding cases secondary to chemo or radiotherapy), who represented 6.7% of our total cases of adult MDS. Median age was 42 (range 18-50). At diagnosis, there were 9 RA, 6 RAEB, 13 RAEB-T, 9 CMML but no RARS. Five patients had a familial history of MDS, and 3 a history of occupational exposure to potential carcinogens. Twenty-one patients received intensive chemotherapy (at diagnosis or during the evolution) but only 8 (38%) achieved complete remission (CR), and median CR duration was 10 months. Five patients were allografted (3 of them as first line therapy): 2 remained disease free after 12 and 10 months, and 3 died of transplant related complications. Median actuarial survival of the 37 patients was 21 months. Significantly shorter survival was seen in patients who had circulating blasts, Bournemouth score greater than 1 or 2, abnormal karyotype (especially monosomy 7) and RAEB or CMML. When compared with our MDS aged more than 50, our MDS aged 50 or less were characterized by more familial cases, more cases of RAEB-T and less cases of RAEB and RARS, more frequent abnormal karyotype and monosomy 7, more frequent progression to AML, identical overall survival but longer survival in RAEB-T and shorter survival in CMML. MDS in younger adults seem relatively often familiar or associated to occupational exposure. They have a poor prognosis with conventional therapeutic approaches and therefore require allografting, whenever possible.

Treating malignant otitis with oral ciprofloxacin

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Oncogenes in the myelodysplastic syndrome

The conversion of normal haemopoietic stem cells to myelodysplastic and then to leukaemic cells is marked by a number of events leading to progressive genetic changes in the abnormal clonal population. Cytogenetic evidence points to abnormalities at specific chromosomal locations, commonly involving chromosomes 5 and 7, where there are a particular concentration of genes directly involved in the regulation of haemopoietic proliferation and differentiation. These include GM-CSF, IL-3, M-CSF, erythropoietin and others. Other genes that may be involved in the preleukaemic process are so-called 'oncogenes' such as met on chromosome 7q and fms on 5q (which codes for the M-CSF receptor) that may be deleted or translocated. The ras gene family is activated by point mutations in a wide variety of malignant states, including myelodysplasia and acute myeloblastic leukaemia. At the present time we do not know the cause of these genetic lesions, their functional significance or the sequence in which they occur.