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Several phenotypic abnormalities of bone marrow (BM) hemopoietic precursors have been associated with disease progression in myelodysplastic syndromes (MDS). We analyzed the influence on overall survival of the expression of lineage and maturation-associated antigens of BM hemopoietic cells quantified in a previous study. In the univariate Cox regression the peripheral platelet count was a significant favourable factor for overall survival. Unfavorable prognostic factors were: WPSS, increase in BM CD34+ cells, increased mean fluorescence intensity (MFI) of CD13 on myelocytes, metamyelocytes and mature neutrophils as well as increased CD45 of myelocytes and mature neutrophils. In a model containing platelet count, WPSS and MFI of CD45 and CD13 on mature neutrophils, only hyperexpression of CD13 and degree of thrombocytopenia were independent risk factors. Therefore, phenotypic features that can also be obtained from PB might be useful for predicting survival in MDS.

The diagnosis of myelodysplastic syndromes (MDS) is based on peripheral cytopenias, bone marrow (BM) morphology and karyotyping. This may be difficult in cases with few dysplastic elements in BM and a normal karyotype. We examined the utility of flow cytometric analysis for the differential diagnosis between MDS and non-clonal disorders (NCD) presenting peripheral cytopenias. Quantitative assessment of CD45, CD16, CD13, CD11b, CD10 and CD64 in granulocytes and monocytes, and CD71 and glycophorin A in erythroblasts besides CD34+ cell count was performed in BM of 31 consecutive newly diagnosed patients with MDS, 11 patients with NCD and 11 healthy controls (BM donors). In MDS, the median number of phenotypic abnormalities found was 3 (1-8). The WPSS score showed a correlation with the total number of changes per case (r=0.48; p=0.002). Decreased SSC in promyelocytes correlated with the peripheral neutrophil count (r=-0.46; p=0.007). In NCD, the normal variation of antigen expression along granulocytic and erythroblast maturation was always maintained. In the discriminant analysis, SSC of CD34+ cells, together with that of promyelocytes and metamyelocytes were able to correctly classify 87% of the cases as clonal or non-clonal. Our quantitative approach permitted to detect at least one abnormality in antigen expression in every case of MDS. However, the most important parameters for differential diagnosis with NCD were the analysis of the granularity in immature cells, especially of the granulocytic series.

Recent studies concerning the pathophysiology of myelodysplastic syndromes (MDS) have shown evidences for the existence of complex interactions between hematopoietic stem cells and the bone marrow (BM) microenvironment. We analyzed the B-lymphocyte maturation in BM of patients with MDS. For this purpose, 41 newly-diagnosed patients were analyzed. Enumeration and characterization of CD34+ and CD34- B-cell precursors and mature B-lymphocytes was performed using multiparameter flow cytometry. BM from eight transplant donors and six orthopedic surgery patients were used as controls. CD34+/CD45(lo) B-cells were found in 17/22 patients with RA/RARS and in 5/13 with RAEB. In patients with RAEB-t and CMML no CD34+ B-cell precursors could be detected. A positive correlation was found between CD34+ and CD34- B-cell precursors (r=0.52). CD34+ B-cell precursors presented an inverse correlation with BM percentage of blasts and peripheral leukocytes and a positive one with hemoglobin. Asynchronous antigen expression (CD19+/CD79a- cells) was found in 7/11 cases of RA/RARS and 6/18 cases of RAEB in which this phenotype was examined. Abnormal patterns of expression for at least one antigen was found in 91% of RA/RARS cases and in 74% of RAEB. Underexpression of TdT and CD79a were the most frequent abnormalities. Our results present evidences of an abnormal B-cell maturation in MDS. This may be an evidence that B-lymphocytes are derived of the abnormal clone. But it may also be the consequence of influences of abnormalities of BM microenvironment leading to an impaired commitment and maturation of the B-cell line in MDS. Studies performed with purified well-characterized B-cells may further elucidate these abnormalities.

Background: The myelodysplastic syndromes (MDS) are a group of stem cell disorders characterized by a reduction in one or more elements of the peripheral blood. Oral manifestations of the disease and oral complications of medical management may result in significant symptoms and have an impact on the systemic condition of the patient. The removal of the infectious focus, such active teeth infection or severe periodontal disease, remains controversial in these patients, due to the increased risk of bleeding and systemic infection., Methods: This paper reports a case of MDS with spontaneous gingival hemorrhage and generalized gingival hyperplasia associated with periodontal disease. This patient underwent several platelet transfusions due to these oral complications. The patient received periodontal therapy, resulting in an improvement of the oral clinical situation and a decrease of gingival hyperplasia., Results: The patient did not present any episode of gingival hemorrhage after the periodontal treatment., Conclusion: The results of this study suggest that periodontal therapy should be performed in MDS patients presenting thrombocytopenia, gingival hyperplasia, and gingival bleeding, with the intent of preventing further hemorrhagic episodes and possible systemic infection.

The role of apoptosis in the pathobiology of myelodysplastic syndromes (MDS) remains controversial. We studied the expression of CD95 and CD95L in CD34+ cells of patients with newly diagnosed MDS by flow cytometry, and examined the relation between this expression and FAB and WHO types, total number of CD34+ bone marrow (BM) cells and the degree of peripheral cytopenias. The patients with refractory anemia (RA) and sideroblastic anemia showed CD34+ cells in numbers comparable to normal donors, but had a higher percentage of CD95/CD34 and CD95L/CD34 positive cells. An inverse correlation was found between these cells and the total CD34+ cells. This was also observed when only patients with RA were analyzed. In RAEB, however, CD95/CD95L expression correlated with CD34+ cells but not with the percentage of BM blasts. After classification by the WHO proposal, the patients with refractory cytopenias with multilineage dysplasia showed features intermediary between RA and RAEB. No significant correlation was seen between the expression of CD95/CD95L and the peripheral blood counts. These results are in keeping with the hypothesis that, as the number of MDS precursors increases during disease progression they become less succeptible to apoptosis.

Background: Clinical studies have shown that amifostine (AMF) improves peripheral cytopenias in myelodysplastic syndromes (MDS). We studied the expression of Fas/FasL on CD34+ cells in low risk MDS and its change after AMF treatment., Patients and Methods: Patients received AMF 400 mg/m2 3x/week for 3 weeks and 2 weeks off treatment. Peripheral blood counts and BM cytology were analysed before and after 2 courses. Quantification of CD34+ cells and CD34/CD95 and CD34/CD95L ones were performed by flow cytometry., Results: Seventeen patients were treated. After 2 months, 8 patients showed a rise in neutrophil count. Hemoglobin increased in 1 and thrombocytes in 2 patients. Before treatment, responding patients presented a significantly lower expression of Fas (median 53%) and FasL (median 26%) than non-responders (85% and 70%, respectively). BM lymphocytes were significantly lower in responders (median 14.5% and 27.4%, respectively). In responders CD34+ cells decreased after treatment. The change in neutrophil count after treatment presented an inverse correlation with the percentage of BM lymphocytes before treatment (r = 0.0-0.58; p = 0.02)., Conclusion: Response to AMF may be influenced by the intensity of the immune reaction in BM.

Aim: Magnetic resonance imaging (MRI) of the femora was used to investigate the marrow cellularity during the evolution of non-transplanted aplastic anaemia (AA) and hypocellular myelodysplastic syndrome (h-MDS) in order to investigate the relationship between this cellularity and disease progression., Methods: Magnetic resonance imaging was performed in adult patients with pancytopaenia and hypocellular bone marrow. Coronal T1 weighted and STIR images were obtained, and analysed semiquantitatively. These data were compared with diagnosis, peripheral blood counts and bone marrow histology at diagnosis and at the time of the MRI examination., Results: Patients were examined 2-84 months after diagnosis (median, 16 months). In AA, 11/13 patients showed a fatty, faint or nodular pattern. In h-MDS, the majority of the patients (10/14) had a scattered or uniform signal pattern. In AA, a significant correlation was found between the degree of femoral cellularity and disease duration. Only three cases had diffuse high signal on STIR: among them, one had paroxysmal nocturnal haemoglobinuria and the other developed acute leukaemia 3 months after MRI examination. Four patients have died: three with h-MDS presenting a scattered (two cases) or a uniform (one case) MRI signal and one with AA (with a nodular pattern), Conclusion: In AA, femoral haemopoiesis is usually not pronounced, and if present, does not contribute to the improvement of blood counts. In h-MDS, patients with discrete femoral haemopoiesis had an improvement in their blood counts with disease duration, similar to that found in AA. Conversely, in patients with pronounced femoral cellularity, blood counts remained stable or had deteriorated since diagnosis. This favours the hypothesis that, as is observed in MDS with a hypercellular marrow, scattered or uniform marrow patterns in femoral MRI are signs of more aggressive disease., (Copyright 2001 The Royal College of Radiologists.)

Mielodysplastic syndromes (MDS) are clonal disorders of the hemopoietic stem cell. About one third of the cases terminate in an acute leukemia, usually acute myeloblastic leukemia. However, few cases of transformation into acute lymphoblastic leukemia (ALL) have been described. We present a case of refractory anemia that transformed into ALL two months after diagnosis and was successfully treated with conventional chemotherapy. Two years later a hyperfibrotic form of MDS was detected in the patient, that soon after terminated in acute megakaryoblastic leukemia. The course of MDS in the present case provides evidence that MDS can involve a pluripotent stem cell, presenting clonal evolution, documented by successive changes in its clinical and hematological features.

A prospective study was undertaken to elucidate the clinical and laboratory differences between de novo acute myeloid leukemia (AML) and AML with trilineage myelodysplasia (AML-TMDS). One hundred and seven patients with AML were diagnosed at the University Hospital between January 1987 and July 1992, and were followed until July 1995. TMDS was identified in 17 of them (16%). With regard to age and sex distribution no difference was found between AML patients with and without TMDS (p = 0.43, p = 0.54, respectively). The duration of symptoms at presentation in AML-TMDS was similar to those observed in de novo AML (p = 0.29). Hemoglobin values and platelet counts were similar in both groups of patients (p = 0.45, p = 0.44, respectively). However, peripheral white blood cell and neutrophil counts, as well as blast counts in AML-TMDS patients were lower than those observed in AML without TMDS patients (p < 0.001 for all of them). Bone marrow blast counts in de novo AML were higher than the values observed in AML-TMDS patients (p < 0.001). TMDS occurred predominantly in M2 and M6 FAB types, and was absent in the M3 type. Bone marrow histology showed no particular feature that could be of diagnostic relevance. The remission rates were similar in both groups of patients (p = 0.55). The same was true for the probability of disease-free survival and overall survival during the period of study (p = 0.50, p = 0.33, respectively). These results suggest that: 1) in AML-TMDS patients, leukemia transformation occurs in a more undifferentiated pluripotent stem cell, leading to a dysplastic residual hemopoiesis besides the blast proliferation; 2) the incidence of TMDS in our group of patients did not influence the clinical outcome after treatment of the disease.