低增生型骨髓增生异常综合征的骨髓病理观察

目的：评估骨髓活检在骨髓增生异常综合征尤其是低增生型病例时的诊断价值。方法：对比分析５３例骨髓增生异常综合征的患者的骨髓涂片与切片的诊断结果。结果：骨髓活检病理检查对于诊断骨髓增生异常综合征,尤其在低增生型骨髓增生异常综合征患者有很大帮助。结论：骨髓活检是确诊低增生型骨髓增生异常综合征的必要手段。     

Dual implication of fibrogenic cytokines in the pathogenesis of fibrosis and myeloproliferation in myeloid metaplasia with myelofibrosis

 Though the diagnostic criteria of myeloid metaplasia with myelofibrosis (MMM) are now well established, the origin and pathophysiological mechanisms of this myeloproliferative disorder remain unclear. Concerning its pathophysiology, myeloproliferation and myelofibrosis are the intrinsic characteristics of the disease. Whereas the myeloproliferation was shown to result from a clonal amplification of primitive progenitor cells, fibroblast proliferation appeared to be polyclonal, thus suggesting that myelofibrosis was a reactive process. The myeloproliferation observed in MMM patients is characterized by an increased number of circulating CD34⁺ hematopoietic progenitors. When cultured at high concentration without added exogenous growth factors, unpurified progenitors from MMM patients gave rise to spontaneous colonies of all myeloid lineages. Such an autonomous growth disappeared when purified CD34⁺ progenitors were plated. These results suggested that growth factors are involved in the dysregulation of proliferation and/or differentiation of MMM hematopoietic progenitors. Cytokines such as PDGF, TGF-β, and bFGF, produced mainly by megakaryocytes, have been proposed to be involved in the abnormal activation of fibroblasts, resulting in fibrosis. Recently the role of the fibrogenic cytokines, TGF-β and bFGF, in the regulation of primitive hematopoiesis has been reported. The aim of this review is to address the question of the potential dual implication of TGF-β and bFGF in the pathogenesis of both myelofibrosis and myeloproliferation in MMM patients. Received: January 7, 1999 / Accepted: April 26, 1999     

Bone marrow histological changes in myelodysplastic syndrome and its clinical significance]

The authors compared bone marrow histological changes in 28 cases of myelodysplastic syndrome (MDS), 21 cases of aplastic anemia and 8 cases of hemolytic anemia. It is shown that abnormal localization of immature precursors (ALIP) is a characteristic change in MDS. The presence of erythroblastic islands and the variance of morphology of megakaryocytes are valuable for diagnosis. The histological method for the observation of lymphoid micromegakaryocytes is not so accurate as cytological method. "ALIP" can more or less help to evaluate the prognosis of MDS. According to the histological changes, it is easy to differentiate the three types of anemia we studied.     

Bone marrow in vitro growth and cytogenetic studies in patients with FAB-classified primary myelodysplastic syndromes

Thirty-eight consecutive patients with a FAB-classified primary myelodysplastic syndrome (MDS) were investigated for in vitro growth of colony-forming units for granulocyte-macrophage precursors (CFU-GM) and cytogenetic analysis of bone marrow cells. Abnormal CFU-GM growth was found in 30 patients (79%), and clonal chromosome abnormalities were found in 13 patients (34%). The eight patients who showed normal CFU-GM growth were either cytogenetically normal (n = 5), or had a 5q-deletion (n = 3) as single or dominating karyotypic abnormality. Among the 30 patients with reduced or no colony growth, ten patients had a clonal chromosome abnormality. Leukemia developed in eight patients. None of them grew any CFU-GM colonies, and three of them were cytogenetically abnormal at the time of diagnosis of MDS. Analysis of the bone marrow in vitro growth for CFU-GM and the karyotype in patients with MDS emphasizes the close relationship between these disorders and manifest acute leukemia. Subgroups of MDS may be defined by a cytogenetic classification (e.g., the 5q-syndrome), and the CFU-GM growth pattern can be of value for predicting leukemic transformation.     

Dermatomyositis and myelodysplastic syndrome with myelofibrosis responding to methotrexate therapy

Dermatomyositis (DM) has not yet been reported as a complication of myelodysplastic syndrome (MDS). A 50-year-old man was diagnosed as having MDS because of the presence of anemia, the appearance of immature cells in peripheral blood, and the abnormal cellular morphology. A few months later, high fever, myalgia and erythema developed. Although DM symptoms were resistant to high-dose corticosteroid administration, methotrexate (MTX) therapy improved not only the symptoms of DM but also hematologic findings related to MDS. This indicates that immunosuppressive therapy including MTX administration can be useful for patients with MDS with autoimmune symptoms.     

Bone marrow patterns in patients with aplastic anaemia and myelodysplastic syndrome: observations with magnetic resonance imaging

Abstract: Bone marrow magnetic resonance imaging (MRI) was obtained in 48 patients with myelodysplastic syndrome (MDS) (35 cases) or aplastic anaemia (AA) (13 cases). The lower thoracic and lumbar spine were evaluated on sagittal plane using a 1.5 Tesla superconducting MR unit with a surface coil. Pulse sequence of STIRs (TR 2000 msec, TI 160 msec, TE 20 msec) were applied. Four distinct patterns of signal intensity (SI) on the STIR images were classified as follows: pattern 1, homogeneously low SI; 2, marginally high SI; 3, heterogeneously high SI; 4, homogeneously high SI. In all 13 patients with AA, STIR images initially revealed pattern 1. In 25 of 35 cases with MDS patients, the STIR images were initially classified as pattern 3. The STIR images of 6 AA and 5 MDS patients with a clinical response to treatment showed pattern 2 similar to that of normal marrow distribution. The STIR images of MDS patients showed an abnormal distribution of SI. Significant signal changes in the STIR images can be observed in successive examinations of the patients, thus facilitating follow-up of the disease and treatment. MRI of the bone marrow provides a noninvasive means of grossly examining a large fraction and is a useful technique in patients with aplastic anaemia or myelodysplastic syndrome.     

Bone marrow lymphoid nodules in myeloproliferative disorders: association with the nonmyelosclerotic phases of idiopathic myelofibrosis and immunological significance

The presence of lymphoid nodules in bone marrow biopsy was investigated at diagnosis in 200 patients with chronic myeloproliferative disorders (MPD). Twelve out of 51 patients with idiopathic myelofibrosis (IM) showed such a feature (23.5%), versus two out of 100 with Ph1-positive chronic myeloid leukaemia, two of 32 with polycythaemia vera, and one of 17 with essential thrombocythaemia, the difference between IM and the remaining MPD being statistically significant (P less than 0.0001). When IM patients were compared for their initial characteristics according to the presence or not of bone marrow lymphoid nodules, patients with such a histological finding showed significantly lower values for either WBC counts, number of primitive cells in the blood, and serum lactic dehydrogenase levels. Moreover, it was observed that virtually all patients with lymphoid nodules were in the nonmyelosclerotic phases of IM. Finally, among the 14 of 32 IM patients (44%) investigated for circulating immune complexes who gave a positive test, a significant association between this immunological abnormality and bone marrow lymphoid nodules was found. The above results reinforce the immunological significance of the finding of bone marrow lymphoid nodules in IM and give support to the hypothesis of an immune component in the pathogenesis of the disorder.     

Bone marrow hypervascularity in patients with myelofibrosis identified by infra-red thermography

Summary Infra-red thermography was used to assess bone marrow vascularity in six patients with myelofibrosis secondary to myeloproliferative disorders (four primary myelofibrosis and two primary proliferative polycythaemia). The technique was evaluated with conventional static and dynamic radio-isotopic imaging and with immunohistochemical staining of bone marrow biopsies. Infra-red thermography identified increased bone marrow blood flow in patients with established myelofibrosis and correlated with dynamic radio-isotopic studies of blood flow and hypervascularity identified by immunohistochemistry. Increased bone marrow blood flow and vascular proliferation was not confined to the central bone marrow but also extended into the peripheral marrow of the long bones. Endothelial cell proliferation may be an initiating event in the pathogenesis of myelofibrosis but evaluation of bone marrow vascularity and blood flow has hitherto relied on invasive and complicated techniques. This study has identified bone marrow hypervascularity in patients with myelofibrosis and shown infra-red thermography to be a simple non-invasive method of assessing vascularity. This non-invasive technique may be used to study disease progression and response to therapeutic regimens in patients with myelofibrosis and to study bone marrow blood flow in other bone marrow disorders.     

Bone marrow and serum connective tissue polypeptides in idiopathic myelofibrosis

Summary The distribution of collagen type VI and tenascin has been determined in both normal and myelofibrotic bone marrow by immunohistological techniques. In normal sections positivity was demonstrated in the periosteum (collagen type VI and tenascin) and in the walls of small blood vessels (tenascin). In contrast, myelofibrotic bone marrow showed an increased deposition of both proteins, especially collagen type VI, although this increase was restricted to the later fibrotic stages of the disease. Serum concentrations of collagen type I (PICP), collagen type III (PIIIP) and laminin (laminin PI) related polypeptides were determined in a further 26 patients. PIIIP levels were significantly raised, in contrast to PICP and laminin PI concentrations. All three markers, however, were significantly elevated in patients with active/transforming disease. Laminin PI and PICP levels showed a strong correlation, indicating a relationship between basement membrane and interstitial collagen metabolism, although they do not appear to offer any advantage over PIIIP for the monitoring of disease activity.     

Allogeneic hemopoietic stem cell transplantation in patients with myelodysplastic syndrome or myelofibrosis

Myelodysplastic syndrome (MDS) and myeloproliferative disorders associated with myelofibrosis (MF) are stem cell disorders, and hemopoietic stem cell transplantation (HSCT) is currently the only therapy with curative potential. Among patients with less advanced MDS, 3 year survivals of 65% to 70% are achievable with HLA-identical related and HLA-matched unrelated donors. The probability of relapse is < 5%. Among patients with advanced disease (> or = 5% marrow blasts), about 35 to approximately 45% and 25 to approximately 30%, respectively, are surviving in remission after transplantation from related or unrelated donors. The incidence of post-transplant relapse is 1035%. Criteria of the International Prognostic Scoring System (IPSS), originally developed for nontransplanted patients, also predict survival following transplantation. Patients with MF, either idiopathic or on the basis of pre-existing disorders, are also transplanted successfully with stem cells from related or unrelated donors. Transplants early in the disease, before leukemic transformation, are successful in 60 to approximately 80% of patients. Success rates are lower in patients who have developed MDS or leukemia. New conditioning regimens have permitted successful HSCT even in patients in the seventh decade of life. Results with a regimen using a combination of busulfan (targeted to predetermined plasma levels) and cyclophosphamide are particularly encouraging. Improved survival with transplants from unrelated volunteer donors may, in part, reflect selection of donors on the basis of high resolution (allele-level) HLA typing. Nevertheless, transplant-related morbidity and mortality, including graft- vs. -host disease, remain challenges that need to be addressed with innovative approaches.     

Bone marrow effects of anagrelide therapy in patients with myelofibrosis with myeloid metaplasia

In a prospective study investigating the therapeutic role of anagrelide in myelofibrosis with myeloid metaplasia, 20 patients received anagrelide in daily oral doses of 0.5-3 mg. 17 patients were evaluable and received anagrelide for a median of 2 years (range 0.5-4 years). No patient had a clinically appreciable benefit. Bone marrow (BM) examinations at baseline and after 6 and 12 months of treatment were available for 17, 17 and 12 patients, respectively. In all evaluable cases, BM megakaryocyte number increased after 6 months of anagrelide treatment. Also, Ulex europaeus agglutinin-1 staining of megakaryocytes revealed a left-shifted maturation pattern in most patients with a platelet response to anagrelide. However, megakaryocyte staining intensity for transforming (TGF-beta) and platelet-derived (PDGF) growth factors was not affected consistently by treatment. No patient had a >/=2 grade change in either BM fibrosis or osteosclerosis. These in-vivo data support our previous in-vitro observations that anagrelide interferes with megakaryocyte maturation rather than proliferation. Lack of a positive treatment effect is consistent with the finding that anagrelide did not significantly alter megakaryocyte expression of TGF-beta and PDGF.     

Allogeneic hemopoietic stem cell transplantation in patients with myelodysplastic syndrome or myelofibrosis

Myelodysplastic syndrome (MDS) and myeloproliferative disorders associated with myelofibrosis (MF) are stem cell disorders, and hemopoietic stem cell transplantation (HSCT) is currently the only therapy with curative potential. Among patients with less advanced MDS, 3 year survivals of 65% to 70% are achievable with HLA-identical related and HLA-matched unrelated donors. The probability of relapse is <5%. Among patients with advanced disease (?5% marrow blasts), about 35～45% and 25～30%, respectively, are surviving in remission after transplantation from related or unrelated donors. The incidence of post-transplant relapse is 1035%. Criteria of the International Prognostic Scoring System (IPSS), originally developed for nontransplanted patients, also predict survival following transplantation. Patients with MF, either idiopathic or on the basis of pre-existing disorders, are also transplanted successfully with stem cells from related or unrelated donors. Transplants early in the disease, before leukemic transformation, are successful in 60～80% of patients. Success rates are lower in patients who have developed MDS or leukemia. New conditioning regimens have permitted successful HSCT even in patients in the seventh decade of life. Results with a regimen using a combination of busulfan (targeted to predetermined plasma levels) and cyclophosphamide are particularly encouraging. Improved survival with transplants from unrelated volunteer donors may, in part, reflect selection of donors on the basis of high resolution (allele-level) HLA typing. Nevertheless, transplant-related morbidity and mortality, including graft- vs.-host disease, remain challenges that need to be addressed with innovative approaches.     

Bone marrow karyotype and prognosis in primary myelodysplastic syndromes

Bone marrow karyotype, survival time, and the rate of progression to leukaemia were studied in 111 unselected patients with primary myelodysplastic syndromes. The 49 patients (44%) with clonal chromosome aberrations had survival time (median 29 months) similar to that found in the 62 patients with normal bone marrow karyotype (24 months, p greater than 0.10). The presence of multiple (greater than 2) abnormalities (17 patients) was strongly associated with poor prognosis, with a median survival of only 7 months (p less than 0.001). Prognostic information could be attributed to 2 specific abnormalities, del(5q) and -7: Presence of del(5q) as the sole anomaly was associated with long survival (36+ months), whereas monosomy 7 was a bad prognostic sign (6 months). The risk for leukaemia development correlated neither with the number of chromosome abnormalities nor with any particular anomaly. Our findings demonstrate the prognostic importance of quantifying the complexity of bone marrow chromosome changes. They also emphasize that different specific abnormalities convey widely different prognostic information in primary myelodysplastic syndromes.     

Treatment of myelodysplastic syndrome with agents interfering with inhibitory cytokines

Results of these trials provide evidence for biological activity and some clinical efficacy of agents potentially blocking inhibitory cytokines in patients with MDS. However, given the limited responses, it appears that factors additional to TNFalpha inhibitory activity contribute to the development of cytopenias in these patients. Further studies are warranted using anti-TNFalpha/anti-inhibitory cytokine approaches, either alone or in combination with other agents, capable of abrogating the effects of additional inhibitory mechanisms in MDS.