DNA content of granulocytes, monocytes, and lymphocytes in the bone marrow smears of patients with myelodysplastic syndromes

Recently, we have reported a high incidence of DNA hypodiploidy defined as DNA index (DI) in blasts/promyelocytes from 39 patients with myelodysplastic syndromes (MDS) found to be without a relationship to cytogenetics. In the present study the DNA content (DI) in granulocytes, monocytes, and lymphocytes measured in the same bone marrow smears from the above patients are reported. DNA hypodiploidy was found in mature cells, not only in myeloid cells (granulocytes and monocytes) but also in lymphocytes. A lower mean DI in each cell type of patients compared to controls was found. Pairwise comparison of the mean DI (+/-SE) in 32 patients with normal (n = 22) and abnormal (n = 10) cytogenetics and controls (n = 8) showed a significantly (P < 0.01) lower value for each group of patients, respectively, in all cell types. No difference was found between the two groups of patients. Presence of weak-Feulgen stained nuclei (DI < 0.40) in granulocytes and monocytes was more pronounced in patients expressing DNA hypodiploid immature cell populations, but only occasionally in lymphocytes, suggesting a link to an apoptotic event and intramedullary cell death. DNA hypodiploidy is shown to be a common feature even in mature cell populations in MDS bone marrows. Clonality, by means of DNA content, appears reasonable as regards the granulocytes and monocytes. DNA hypodiploid lymphocytes, on the other hand, might be small blasts (stem cells) or dying cell populations of unknown origin.     

正常核型和异常核型骨髓增生异常综合征的细胞形态学特点比较

目的:比较正常核型和异常核型骨髓增生异常综合征(MDS)的细胞形态学的特点。方法:回顾分析82例MDS患者,通过对正常核型和异常核型MDS患者的细胞形态进行观察,分析二者形态学的差别。结果:核型异常组31例,占37.8%,核型正常组51例,占62.2%,2组外周血比较,核型异常组易出现原粒细胞、早幼红细胞、大红细胞,P<0.05;骨髓细胞形态比较,核型异常组三系病态造血比例高(>30%),P<0.05;原粒、淋巴样小巨核和畸形血小板比例高,P<0.05;核型异常组红系病态造血易见子母核、奇数核和多核,P<0.05;核型异常组有6例转为急性白血病。结论:异常核型MDS较正常核型组细胞病态造血发生率明显增高,原始细胞比例增高,转为白血病的比例高,预后差。     

Impact of marrow cytogenetics and morphology on in vitro hematopoiesis in the myelodysplastic syndromes: comparison between recombinant human granulocyte colony-stimulating factor (CSF) and granulocyte-monocyte CSF.

Marrow cells from 36 patients with myelodysplastic syndromes (MDS) (13 refractory anemia [RA], 14 refractory anemia with excess of blasts [RAEB], 9 RAEB in transformation [RAEB-T]) were evaluated for their in vitro proliferative and differentiative responsiveness to recombinant human granulocyte colony-stimulating factor (G-CSF) or granulocyte-monocyte CSF (GM-CSF). GM-CSF exerted a stronger proliferative stimulus than G-CSF for marrow myeloid clonal growth (CFU-GM) in these patients (44 v 12 colonies per 10(5) nonadherent buoyant bone marrow cells [NAB], respectively, P less than .025). GM-CSF stimulated increased CFU-GM growth in the 16 patients with abnormal marrow cytogenetics in comparison with the 20 patients who had normal cytogenetics (52 and 30 colonies per 10(5) NAB, respectively, P less than .05), whereas no such difference could be demonstrated with G-CSF (11 and 16 colonies per 10(5) NAB, respectively). In contrast, granulocytic differentiation of marrow cells was induced in liquid culture by G-CSF in 15 of 32 (47% patients), while GM-CSF did so in only 4 of 18 (22%) patients (P less than .025) including, for RAEB/RAEB-T patients: 9 of 18 versus 0 of 9, respectively (P less than .025). For MDS patients with normal cytogenetics, G-CSF- and GM-CSF-induced marrow cell granulocytic differentiation in 12 of 18 (67%) versus 3 of 11 (27%), respectively (P less than .025), contrasted with granulocytic induction in only 3 of 14 (21%) and 1 of 7 (14%) patients with abnormal cytogenetics, respectively. We conclude that G-CSF has greater granulocytic differentiative and less proliferative activity for MDS marrow cells than GM-CSF in vitro, particularly for RAEB/RAEB-T patients and those with normal cytogenetics.     

Cytogenetics and clinical features of pediatric myelodysplastic syndrome in Japan

We analyzed the cytogenetics and clinical features of pediatric myelodysplastic syndrome (MDS) in Japan. Data on patients (<16 years) diagnosed with MDS from 1990 to 2000 were retrospectively collected from pediatric hematologists in 234 institutions. Chromosome analysis was successfully performed in 255 of 277 MDS patients. The numbers of patients with refractory anemia, refractory anemia with ringed sideroblasts, refractory anemia with excess of blasts (RAEB), refractory anemia with excess of blasts in transformation (RAEBt), chronic myelomonocytic leukemia, and juvenile myelomonocytic leukemia were 67 (24 %), 51 (18 %), 51 (18 %), 20 (7 %), and 65 (23 %), respectively. The other 23 patients (8 %) could not be classified specifically. The distribution of childhood MDS in Japan according to the French–American–British subclassification was similar to that in other countries. However, we identified a higher incidence of therapy-related cases. As for relationship between cytogenetics and prognoses, abnormal karyotypes were related to poorer prognoses than normal karyotype (P < 0.01). However, patients with trisomy 8 had prognoses comparable to those with normal karyotypes. Complex karyotypes were associated with poorer prognoses among RAEB and RAEBt patients. In conclusion, prognosis of pediatric MDS is related to cytogenetics. A more precise diagnosis and classification system is needed for childhood MDS.     

DNA content and cell cycle analysis of bone marrow cells in myelodysplastic syndromes (MDS)

DNA distribution in bone marrow cells from 10 normal subjects and 34 patients with MDS (24 with refractory anaemia (RA) and 10 with excess blasts (RAEB] was determined by flow cytometry using a FACS III. DNA histograms were resolved into G0/1, S and G2/M compartments by fitting Gaussian distributions and the DNA content of G0/1 cells, expressed as DNA index (DI), was determined. In 19 MDS patients the DI was outside the normal range, those with RA tending to be hyperdiploid. Two patients with RAEB had a second G0/1 peak. In five cases of RA the number of cells in G0/1 was below the normal range and the mean value was significantly lower than normal for this group as a whole (P = 0 X 018). Eleven (RA) patients had a higher percentage of cells in G2/M than normal (P = 0 001). In RAEB patients there is a suggestion of increased numbers in G0/1 and a decrease in S phase and G2/M cells. All three of the deaths amongst RA patients and four out of the five deaths in RAEB patients since the beginning of this study were associated with an abnormal DI at the initial investigation.     

Flow cytometric evidence for minimal residual disease and cytological heterogeneities in acute lymphoblastic leukemia with severe hypodiploidy

Two subpopulations of small and large leukemia cells and binucleated cells were present in the bone marrow of a 10-year-old girl with acute lymphoblastic leukemia (ALL). Cytogenetic studies showed some cells with a karyotype of 34,X,-X,-2,-3,-4,-5,-7,-9,-13,-15,-16,-17,-20, and others with a karyotype that was exactly double the chromosome set in the cells with 34 chromosomes. Flow cytometric (FCM) examination of surface common ALL antigen (CALLA) and DNA content of the lymphoblasts led to the identification of the primary hypodiploid DNA stemline (DI = 0.72), which corresponds to the small-sized blasts, and the secondary hyperdiploid DNA stemline (DI = 1.44), which corresponds to the large-sized blasts. Sequential bone marrow examinations with FCM and cytogenetics revealed the persistence of the primary hypodiploid clone during remission and their proliferation with chromosomal evolution at full relapse. These results suggest that more rational inductive therapy should be designed to achieve the favorable outcome of ALL with severe hypodiploidy and that FCM is a useful tool to monitor the minimal residual disease of this subgroup in ALL.     

Fludarabine, cytarabine, G-CSF and idarubicin (FLAG-IDA) for the treatment of poor-risk myelodysplastic syndromes and acute myeloid leukaemia

Nineteen patients with high-risk myelodysplastic syndrome (MDS)/acute myeloid leukaemia (AML) received fludarabine, cytarabine, granulocyte-colony stimulating factor (G-CSF), and idarubicin chemotherapy ( de novo MDS/MDS-AML, nine; relapsed/refractory MDS/AML, seven; therapy-related MDS, three). Median age was 44 years and median disease duration 10 months. 16/19 (84%) patients had abnormal cytogenetics with seven (37%) harbouring abnormalities of chromosome 7. 18/19 (94.7%) patients responded to FLAG-idarubicin with 12 (63%) achieving complete remission (CR) (<5% blasts and normal cytogenetics). 7/9 (78%) patients with de novo MDS/MDS-AML achieved CR compared to 5/10 (50%) with alternative diagnoses. Response was associated with age < 50 years, disease duration < 3 months, and cytogenetics other than abnormalities of chromosome 7. Haemopoietic regeneration was rapid in most patients and there were no toxic deaths. Nine patients received a second course of chemotherapy, three have proceeded to allogeneic bone marrow transplant and three to autologous blood stem cell/bone marrow transplantation. Follow-up is short (median 10 months). 12/19 (63%) patients remain alive and 5/12 (42%) have relapsed at a median 5 months following CR achievement. FLAG-idarubicin was well tolerated. High rates of morphological and cytogenetic remission, especially in de novo MDS, offer a window of opportunity for assessment of autologous BMT in this group of diseases where no treatment except alloBMT has led to prolongation of survival.     

Genomic instability in bone marrow failure syndromes

Aneuploidy is frequently seen in leukemia and myelodysplasia (MDS) but was thought to be uncommon in aplastic anemia (AA). We examined marrow cells from 96 unselected patients with bone marrow failure syndromes to assess the frequency of undetected aneuploidy for chromosomes 7 and 8 by fluorescence in situ hybridization (FISH) as compared to routine cytogenetic analysis. Twenty-eight percent (27/96) of patients had an abnormal karyotype. FISH identified an additional 27 patients with undetected monosomy 7 or trisomy 8. Those patients with undetected monosomy 7 generally had a poor clinical outcome, suffering from lack of response to medical therapy or early death. In one AA/MDS patient with normal cytogenetics, FISH identified a large population of monosomy 7 cells, which clearly heralded a clinical relapse. In another patient, FISH studies were used to delineate instability of chromosome 8, with apparent disease progression from AA to MDS. We conclude that undetected aneuploidy exists in marrow cells of a significant percentage of patients with bone marrow failure syndromes.     

Prognostic value of cytogenetics in adult patients with Philadelphia-negative acute lymphoblastic leukemia

The prognostic value of cytogenetics in adult acute lymphoblastic leukemia (ALL) is not as established as in childhood ALL. We have analyzed the outcome and prognostic value of karyotype in 84 adults diagnosed with Philadelphia-negative ALL from a single institution that received induction chemotherapy and had successful karyotype performed. The most frequent finding was normal karyotype in 35 (42%) cases, followed by aneuploidies in 20 cases (24%) and t(4;11)(q21;q23)/MLL/AF4 in 5 (6%), and the remaining 24(27%) cases carried miscellaneous clonal abnormalities. The group of patients with t(4;11)(q21;q23)/MLL/AF4, hypodiploidy and low hyperdiploidy (less than 50 chromosomes) showed a worse outcome than those with normal karyotype and miscellaneous abnormalities in terms of overall survival (OS) (3 years OS; 47% vs. 13%, p?=?0.014) and relapse-free survival (RFS) (3 years RFS; 44% vs. 27%, p?=?0.005). Other cytogenetic prognostic classifications reported to date were tested in our series, but any was fully reproducible. In conclusion, karyotype is a useful tool for risk assessment in adult ALL. We have confirmed the bad prognosis of t(4;11)(q21;q23)/MLL/AF4 and hypodiploidy. Besides, low hyperdiploidy could also define a high-risk group of patients who might be candidates for more intensive treatment.     

Cytogenetic classification in Korean multiple myeloma patients: prognostic significance of hyperdiploidy with 47–50 chromosomes and the number of structural abnormalities

Chromosomal abnormalities are important prognostic factors for patients diagnosed with multiple myeloma (MM). We retrospectively reviewed the clinical and laboratory data of 525 MM patients to assess the abnormalities frequently found by conventional cytogenetic analysis and to determine their relationship to prognosis and clinical parameters. Samples from 222 (42.3%) patients had abnormal karyotypes. Hyperdiploidy‐1 (>50 chromosomes), hyperdiploidy‐2 (47–50 chromosomes), pseudodiploidy (46 with abnormalities), and hypodiploidy (<46 chromosomes) were found in 55, 44, 42, and 81 patients, respectively. The median overall survival (OS) was significantly shorter in patients with hyperdiploidy‐2 (20.9 months), pseudodiploidy (19.9 months), and hypodiploidy (18.3 months) compared with patients with normal karyotype (66 months) and hyperdiploidy‐1 (55.4 months) (P < 0.001). Among patients with chromosomal abnormalities, those with 1q amplification had a shorter median OS (17 vs. 25.1 months, P = 0.018). Patients with a chromosome 13 deletion in the pseudodiploidy group also had a shorter OS. A karyotype with more than six structural abnormalities was found to have the most significant independent prognostic value by multivariate analysis. These data show that hyperdiploidy with 47–50 chromosomes should be recategorized as an unfavorable risk group, and the number of structural abnormalities needs to be considered as an important factor for prognosis. In conclusion, our findings imply that subclassification of chromosomal abnormalities by conventional cytogenetics could be applied to the prognostic assessment of MM.     

Prognostic implications of morphology and karyotype in primary myelodysplastic syndromes

Forty-nine patients with primary myelodysplastic syndromes (MDS) were subclassified according to French-American-British (FAB) Cooperative Group criteria. Eight patients had acquired idiopathic sideroblastic anemia (AISA), ten had chronic myelomonocytic leukemia (CMMoL), 14 had refractory anemia (RA), nine had refractory anemia with excess blasts (RAEB), and five had refractory anemia with excess blasts in transformation (RAEB-T); three patients could not be subclassified. The actuarial median survival for patients with AISA or with RA had not been reached at 60 months of follow-up. The median survival times for patients with CMMoL, RAEB, and RAEB-T were 25, 21, and 16 months, respectively. The percentages of patients with each subtype who developed ANLL were none in AISA, 20% in CMMoL, 7% in RA, 56% in RAEB, and 40% in RAEB-T. Patients with CMMoL had a poor prognosis independent of transformation to acute nonlymphocytic leukemia (ANLL), whereas patients with RAEB and RAEB-T had a high incidence of transformation and short survival times. Clonal chromosomal abnormalities were present in bone marrow cells from 19 patients at the time of diagnosis, and two others developed an abnormal karyotype at the time of leukemic transformation. The most frequent abnormalities, including initial and evolutionary changes, were trisomy 8 (9 patients), deletion of 5q (4 patients), and deletion of 20q (4 patients). The median survival times were 32 months for patients with an abnormal karyotype, and 48 months for those with a normal karyotype (P = 0.2). Specific chromosomal abnormalities were not associated with particular histologic subtypes; however, a high percentage of patients with RAEB and RAEB-T had an abnormal clone (89% and 80%, respectively). The percentages of patients with clonal abnormalities were 13% for AISA, 20% for CMMoL, and 29% for RA. The MDS transformed to ANLL in 42% of patients with an abnormal karyotype, compared to 10% of those with an initially normal karyotype (P less than .01). Among patients with RA, RAEB, and RAEB-T, the risk of leukemic transformation was confined to those with an abnormal karyotype (P less than .01). Thus, in the present study, morphology and karyotype combined were the best indicators of outcome in patients with MDS.     

Detection of cryptic chromosomal lesions including acquired segmental uniparental disomy in advanced and low-risk myelodysplastic syndromes

OBJECTIVES: Using metaphase cytogenetics (MC), chromosomal defects can be detected in 40% to 60% of patients with myelodysplastic syndromes (MDS); cytogenetic results have a major impact on prognosis. We hypothesize that more precise methods of chromosomal analysis will detect new/additional cryptic lesions in a higher proportion of MDS patients. METHODS: We have applied single nucleotide polymorphism microarrays (SNP-A) to perform high-resolution karyotyping in MDS to determine gene copy number and detect loss of heterozygosity (LOH). RESULTS: Using this method, chromosomal defects were found in 82% of MDS patients vs 50% as measured by MC; lesions were present in 68% of patients with normal MC, while in 81% of those with abnormal MC, new aberrations were found. In addition to gains or losses of chromosomal material, areas of LOH due to segmental uniparental disomy were found in 33% of patients. CONCLUSION: SNP-A findings demonstrate that chromosomal lesions are present in a much higher proportion of patients than predicted by traditional cytogenetics. These lesions may reflect an underlying generalized chromosomal instability in MDS. Additional previously cryptic defects may explain the clinical variability of MDS. New lesions may have important prognostic implications, suggesting that, in the future, SNP-A-based karyotyping may complement MC in laboratory evaluation of MDS.     

间期荧光原位杂交技术检测骨髓增生异常综合征-7/7q-染色体异常的价值

目的探讨应用间期荧光原位杂交（FISH）技术检测7号染色体/7号染色体长臂缺失（-7/7q-）异常在骨髓增生异常综合征（MDS）中的价值。方法采用常规细胞遗传学（CC）和间期FISH检测技术对72例MDS患者和8例正常对照者的骨髓细胞进行分析,比较CC和FISH检测-7/7q-异常的情况。结果 72例MDS中,12例CC检测阳性,发生率16.7%。间期FISH检测24例阳性,发生率33.3%。两种方法检出率有统计学差异（P〈0.05）。结论间期FISH技术敏感性高于CC,并能发现和纠正CC分析中的漏检异常。     

Expression analysis of proteins involved in the non homologous end joining DNA repair mechanism, in the bone marrow of adult de novo myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are characterized by genetic instability which is associated with abnormal DNA repair mechanisms. The most lethal type of DNA damage are double strand DNA breaks (DSBs), which are mainly repaired by Non Homologous End Joining Mechanism (NHEJ), whose core enzyme components include the Ku70/Ku80 heterodimer, DNA–PKcs, XRCC4 and DNA Ligase IV. The aim of the present study was the analysis of expression of proteins required for NHEJ in bone marrow cells of adult de novo MDS and their association with clinical characteristics and prognosis. Our analysis included 48 cases of MDS; 19 RA, 5 RARS, 19 RAEB, 3 RAEB-T, 1 CMML, 1 transformation to AML according to FAB classification. The expression of the enzymes Ku70, Ku80, XRCC4, DNA-PKcs and Ligase IV was determined by Western Blotting. The mean Ligase IV expression value was significantly lower in MDS patients compared to normal controls (0.53 vs. 0.78, p?=?0.03). A negative correlation was found between karyotype risk group and Ligase IV values. (p?=?0.05). Moreover, Ku70 expression levels were significantly lower in patients with a good prognosis karyotype (p?=?0.04). Furthermore, a negative correlation between Ku70 expression values and Hb levels was observed (p?=?0.04). Finally, a positive correlation was observed between enzyme Ku70 expression values and level of blasts (p?=?0.04). Our findings suppor-t a potential role of NHEJ enzyme Ligase IV in the pathogenesis of MDS. Larger numbers of cases need to be screened in order to draw definite conclusion.     

Cytogenetic abnormalities in the myelodysplastic syndromes and occupational or environmental exposure

Patients with myelodysplastic syndromes (MDS) have high frequencies of cytogenetic abnormalities and evidence is accumulating of associations between exposure history and primary MDS. The objective of this article is to examine the relationship between histories of occupational or environmental exposure and presence of cytogenetic abnormalities. A case control study of MDS patients estimated lifetime exposure to more than 90 potential hazards in 400 age, sex, and area of residence matched patient and control pairs. A parallel cytogenetics study undertaken at time of diagnosis, independently of any knowledge of exposure history, identified 75 cytogenetically abnormal and 139 normal (186 not studied). Odds ratios of MDS patients and their matched controls were compared for 3 groups: cytogenetically abnormal, normal, and not known. The odds ratios for all exposures combined were possibly higher among cytogenetically abnormal 2.0 (95% confidence interval 0.8-5.9) than among normal 1.0 (0.6-1.8). This pattern was observed for exposure to semimetals, abnormal 4.0 (0.4-195.1) and normal 0.5 (0.1-1.0) and inorganic dusts, 1.6 (0. 6-3.8) and 0.4 (0.1-1.4) respectively. The pattern was principally in abnormalities in chromosomes 5 and 7. For organic chemicals and radiation, the odds ratios for both cytogenetically abnormal and normal were marginally raised: organic 1.8 (0.6-6.0) and 1.3 (0.6-2.9), respectively, and radiation 1.7 (0.5-5.6) and 1.3 (0.4-4.7) respectively. For radiation, abnormalities were mostly in chromosome 8. This study of association between exposures and cytogenetics in primary MDS complements those previously reported in secondary MDS and may provide some insight into pathogenetic mechanisms that lead to development of MDS. (Blood. 2000;95:2093-2097)     

In vivo effects of decitabine in myelodysplasia and acute myeloid leukemia: review of cytogenetic and molecular studies

Low-dose demethylating agents such as 5-aza-2'-deoxycytidine (decitabine, DAC) and 5-azacytidine (azacitidine, Vidaza) have been explored for the treatment of myelodysplasia, acute myeloid leukemia, and hemoglobinopathies since the early 1980s, aiming to revert a methylator phenotype. Originally, the treatment rationale in hemoglobinopathies was to achieve demethylation of the hypermethylated and hence silent gamma-globin gene locus, thus reactivating synthesis of hemoglobin F (HbF). In myelodysplastic syndrome (MDS), cytogenetic analyses are mandatory for risk stratification and for monitoring response to drug treatment. The current knowledge regarding cytogenetic subgroups as predictors of response to low-dose decitabine in MDS as well as cytogenetic responses caused by demethylating agents is summarized in this review. Decitabine treatment is associated with a response rate that is higher in patients with high-risk cytogenetics (i.e., complex karyotype and/or abnormalities of chromosome 7) than in patients with intermediate-risk cytogenetics (two abnormalities or single abnormalities excluding 5q-, 20q-, and -Y). Following decitabine treatment of patients with abnormal karyotype, approximately one-third achieve a major cytogenetic response that can be confirmed by FISH analyses, while in two-thirds of patients, the abnormal karyotype persists but hematologic improvement may be observed during continued treatment. The most frequently studied gene in myelodysplasia is the cell cycle regulator p15(INK4b). Hypermethylation of p15(INK4b) in MDS is reversed during treatment with decitabine, resulting in reactivation of this gene. In hemoglobinopathies, treatment with demethylating agents leads to reactivation of fetal HbF (the gamma-globin gene locus also possibly being another target for reactivation in MDS), and thus, HbF may potentially act as surrogate marker for activity of decitabine. Other, thus far unidentified hypermethylated genes may also be targets for demethylating agents.     

DNA Index in childhood acute lymphoblastic leukaemia: a karyotypic method to validate the flow cytometric measurement

The DNA index (DI) is a prognostic factor in childhood acute lymphoblastic leukemia (ALL). The accuracy of DI measurement is important for treatment stratification: hyperdiploidy with DI ≥ 1.16 is predictive of favorable prognosis whereas hypodiploidy is associated with poor prognosis. The aim of this study was to validate the accuracy of the DI measured by flow cytometry (FCM) by comparison with the karyotype. From samples of 112 childhood ALL, we created a formula to calculate a theoretical DNA index (tDI) based on the blast cell karyotype, taking into account the additional or missing chromosome material of the major clone. FCM DI correlated with tDI calculated from karyotype (R = 0.987) and with modal chromosome number (DI = 0.0202 × Modal NB + 0.0675 and R = 0.984). In three cases a hypodiploid blast cell population was detected by FCM, while only the duplicated clone was identified by the karyotype. The strong correlation between tDI and DI validates the accuracy of FCM quantification, which is technically fast on fresh or frozen samples. If the karyotype is essential to analyze chromosomal abnormalities, FCM provides complementary information in aneuploid ALLs, either by confirming the cytogenetic data or by detecting additional clones not identified when only using cytogenetic data.     

Cross-validation of prognostic scores in myelodysplastic syndromes on 386 patients from a single institution confirms importance of cytogenetics

In myelodysplastic syndromes (MDS) different prognostic risk analysis systems based on clinical and morphological data are used for predicting survival. Data on diagnostic and prognostic relevance of karyotype aberrations have prompted the development of scores including cytogenetics. The aim of this study was to assess and compare the explanatory power of different scoring systems and to assess the additional explanatory power of cytogenetics by evaluating the clinical and laboratory data of MDS patients from a single institution. Data of 386 MDS patients was available, with cytogenetic analysis at time of diagnosis in 256. Clinical/morphological scores: Bournemouth, modified Bournemouth and Düsseldorf; and scores including cytogenetics: Lausanne-Bournemouth, Lille and the International Prognostic Scoring System (IPSS), were calculated and their predictive power was compared for both overall survival and preleukaemic duration. Each of the scores had significant correlation on both endpoints. Calculating the prognostic value of different cytogenetic aberrations we found that differentiating between evidence for no aberration, single aberrations excluding chromosomes 7 and 8, aberrations on chromosomes 5, 7 or 8 and complex aberrations was important. These data were incorporated in a 'prognostic index cytogenetics' (pi score). Cytogenetic scores significantly improved the prognostic value of the best clinical/morphological score in regard to both overall survival and preleukaemic duration. In conclusion, our data further stress the importance of cytogenetics for predicting prognosis in MDS.     

Extended cytogenetic follow-up of patients with myelodysplastic syndrome (MDS)

The prognostic significance of clonal karyotype status in myelodysplastic syndrome (MDS) is assessed after an extended follow-up period of 5 years. There are three karyotype, single abnormalities or multiple abnormalities at the time of referral. However, there is no correlation between the size of the abnormal clone and prognosis. Karyotype status has independent prognostic significance in 'high risk' MDS so that patients with a refractory anaemia with excess of blasts (RAEB)/RAEB in transformation (RAEB-t) and a normal karyotype survive significantly longer than those with an abnormal karyotype (P < 0.001) and do not differ significantly from patients with refractory anaemia (RA). Significant differences in survival according to karyotype status are also seen in patients with chronic myelomonocytic leukaemia (P < 0.001) but not in those with primary acquired sideroblastic anaemia and RA. Among patients studied sequentially, those who retained a normal karyotype survived significantly longer than those who developed an abnormality on follow-up (P < 0.001). The risk of leukaemic transformation was also increased in patients who presented with or subsequently developed a clonal karyotype abnormality compared with those who remained normal (P < 0.05).     

Immunophenotypic analysis of erythroid dysplasia and its diagnostic application in myelodysplastic syndromes

Background/Aim: Abnormal immunophenotypes of haematopoietic cells in myelodysplastic syndromes (MDS) have been identified by flow cytometry (FCM) as a typical characteristic of myeloid dysplasia. Considering that most MDS patients show varying degrees of erythroid dysplasia, we analysed the immunophenotypic feature of erythroblasts to evaluate its diagnostic application in MDS. Methods: Erythroid antigens CD71 and CD105 expression were analysed using FCM. The development index (DI) acquired by log transformation of the CD71/CD105 expression ratio was used to denote the erythroid maturation and distinguish patients with non‐clonal cytopenias from low‐risk MDS. The diagnostic quality of DI in distinguishing MDS from non‐clonal cytopenia patients was evaluated using the receiver–operator characteristic (ROC) curve. Results: Under‐expression of CD71 and over‐expression of CD105 were detected in erythroblasts of MDS patients compared with non‐clonal cytopenias. The diagnostic test showed good diagnostic power that the area under the ROC curve was greater than 0.9. The diagnostic sensitivity and specificity were 75.6% and 92.3%, respectively, according to the DI threshold defined by the ROC curve in low‐risk MDS patients with normal karyotypes. Moreover, the DI showed a positive correlation with the haemoglobin level, and the MDS patients with lower DI usually showed frequent red cell transfusion. The patients with a lower DI generally had the HLA‐DR15 allele or marrow hypocellularity. Conclusion: Developmental defects and immune‐associated factors may contribute to the erythroid dysplasia. The DI derived from ratios of CD71 and CD105 expression is a useful marker to characterise dyserythropioiesis associated with MDS and can be helpful in distinguishing it from dyerythropoiesis associated with non‐clonal disorders.