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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 389 (1980), S. 307-324 
    ISSN: 1432-2307
    Keywords: Polycythemia vera ; Secondary polycythemia ; Histopathology ; Ultrastructure ; Cytogenetics ; Bone marrow biopsy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Clinical and morphological studies including light microscopy, electron microscopy and karyotyping of the bone marrow, were performed on a total of 164 patients with polycythemic conditions. A final diagnosis was obtained from clinical findings and histopathology of plastic embedded core biopsies of the bone marrow including sequential examinations. 51 patients revealed a secondary polycythemia whereas 113 displayed polycythemia vera (P. vera). In this last group 83 cases have persisting P. vera. 30 showed a transgression towards chronic myeloid leukemia with or without accompanying myelofibrosis — osteomyelosclerosis (so called chronic megakaryocytic-granulocytic myelosis — CMGM). The histopathology of the bone marrow in P. vera revealed consistent alterations which are useful in distinguishing this disorder from secondary polycythemia (SP) and CMGM: depletion of iron storage, increased neutrophilic granulopoiesis but no gross atypia in maturation, polymorphism of megakaryocytes with conspicuous giant forms and dilatation and increased branchings of venous sinusoids. Electron microscopic findings were in agreement and showed further abnormalities of cytological maturation in the erythrocytic and granulocytic lineage. Cytogenetic studies in 27 non-treated patients with P. vera revealed the Philadelphia chromosomes in 2 cases, whereas in SP only minor chromosomal anomalies have been encountered in a few patients. It is concluded that histopathology of trephine biopsies of the bone marrow is an invaluable aid to establish a correct diagnosis, differentiating P. vera from the other potentially polycythemic disorders and helping to detect a possible progression towards leukemia at an early stage. Cytogenetic investigations may show early structural and numerical abnormalities of the karyotype and possibly precede a presumptive transgression towards myeloid leukemia (CMGM). A simultaneously performed histological and chromosomal examination of bone marrow samples is therefore desirable in each case of a polycythemic condition.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 389 (1980), S. 325-341 
    ISSN: 1432-2307
    Keywords: Polycythemia vera ; Myeloid leukemia ; Histopathology ; Ultrastructure ; Cytogenetics ; Survival
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Of 113 Patients with polycythemia vera (P. vera) who had been followed for the last 8 years, 30 cases (27%) developed myeloid leukemia with fibrosis of the bone marrow. Core biopsies of the bone marrow including sequential examinations in several cases revealed neoplastic proliferation of neutrophil granulopoiesis and an atypical megakaryopoiesis with accompanying fibrosis of varying degrees. These alterations were consistent with a subtype of chronic myeloid leukemia — the so called chronic megakaryocytic-granulocytic myelosis (CMGM) — and correspond to (agnogenic) myeloid metaplasia with osteomyelofibrosis/-sclerosis. 5 of those 30 patients showed spontaneous transgression into myeloid leukemia, none of them had received any ionizing radiation or cytostatic therapy. A blast crisis or so called acute leukemia in P. vera was seen only in one patient who was treated by an overdose of radioactive phosphorus and later evolved into osteomyelosclerosis with blastic transformation. These findings of a chronic leukemia or CMGM arising from P. vera was further confirmed by atypia of ultrastructure and particularly by our cytogenetic evaluation. Chromosomal studies showed a Ph′-chromosome to be present in 5 of 8 patients with CMGM and myelofibrosis. Clinical and statistical evaluation of survival times showed a median survival expectation of all P. vera patients of 15 years. Life expectancy of the patients who still displayed P. vera was more favorable than those cases with transformation into CMGM, disregarding any therapy. Transformation of P. vera into CMGM occurred about 8 years after the onset of disease and following transgression into leukemia, half of these patients were dead after 2.5 years. Our results demonstrate that P. vera represents a “panmyelosis” with an inherent malignant nature, or a neoplastic proliferation of all three cell lines. This concept is supported by several facts: atypia of cytological differentiation as observed by light- and electron microscopy of the bone marrow, chromosomal anomalies with aneuploidy and an infrequent Ph'-marker, spontaneous transgression into chronic myeloid leukemia or its subtype CMGM without relevant therapy and a clonal evolution as shown by enzymatic studies reported in the literature.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-2307
    Keywords: Megakaryocytes ; Sinus wall ; Transmural migration ; 3D-reconstruction ; Double-immunostaining
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Using sequential double-immunostaining and a newly-developed three-dimensional (3D-) reconstruction technique on serially cut sections from bone marrow trephines, we studied the transmural passage of megakaryocytes through the sinus wall. Biopsies derived from patients with primary (idiopathic) osteomyelofibrosis were exposed to monoclonal antibody against type IV collagen to delineate the sinus walls and also the frequently thickened basement membrane. Staining with the primary antibody was followed by Y2/51 (CD61) to identify all elements of megakaryopoiesis. In most instances serial sectioning and 3D-reconstruction revealed an amoeboid shape of megakaryocytes and a tandem-like arrangement in close spatial contact with the abluminal surface of the sinus wall. Preceded by formation of cytoplasmic processes, straight penetration of entire megakaryocytes through gaps in the sinus walls into the lumen was seen. Where collagen deposits apparently presented a barrier, a mole-like tunnelling through the basement membrane material (type IV collagen) was recognizable. Our findings are in keeping with the assumption that megakaryocyte locomotion is an essential requirement for normal thrombocytogenesis.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Der Pathologe 16 (1995), S. 128-138 
    ISSN: 1432-1963
    Keywords: Schlüsselwörter Dreidimensionale Rekonstruktion ; Lichtmikroskopie ; Serienschnitte ; Megakaryozyten ; Primäre Osteomyelofibrose ; Knochenmark ; Key words Three-dimensional reconstruction ; Light microscopy ; Serial sections ; Megakaryocytes ; Primary osteomyelofibrosis ; Bone marrow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Computer-based three-dimensional reconstruction of serially cut light microscopic sections is being increasingly used in medical and biological research. Compared with conventional two-dimensional evaluation of histological sections, complex histotopographical relationships and structural details are easy to assess and could be imposingly visualized on the graphics screen. Because of the rapid progress in modern computer hardware, uncomplicated and fast reconstruction systems are available on standard personal computers. Therefore, 3D reconstruction is applicable for a wide range of investigations that warrant 3D exploration. Own results are presented and the principles of 3D reconstruction, as well as the problems and difficulties in this new technique, are discussed. The complex ameboid morphology of megakaryocytes in bone marrow of primary (idiopathic) osteomyelofibrosis is examined with this new method in combination with selective immunohistochemical staining procedures. 3D reconstruction can visualize the complexity of cytoplasmic and nuclear formation impressively. Moreover, the models generated permit exact quantitative measurements of cell morphology. The technique presented is a powerful tool for anatomical-morphological investigations and can furthermore increase our comprehension of complex histomorphological objects.
    Notes: Zusammenfassung Computergestützte dreidimensionale Rekonstruktionsverfahren von lichtmikroskopischen Serienschnitten haben sich in den letzten Jahren in allen Bereichen der medizinisch-biologischen Forschung etablie-ren können. Im Vergleich zur konventionellen zweidimensionalen Schnittbetrachtung lassen sich komplexe histotopographische Beziehungen sowie Strukturcharakteristika besser erfassen und auch eindrucksvoll darstellen. Aufgrund der schnell fortschreitenden Entwicklung im Bereich der Computertechnik sind heutzutage Rekonstruktionssysteme auch auf preisgünstigen Rechnersystemen verfügbar, so daß sich dieser neuen Methode ein zunehmendes Anwendungsgebiet erschließt. Anhand von eigenen Befunden werden die Grundlagen der 3 D-Rekonstruktion besprochen sowie Schwierigkeiten und Probleme dieser neuen Technik diskutiert. In Kombination mit kontrastreichen und selektiven immunhistochemischen Färbungen wird beispielhaft die komplexe amöbenartige Morphologie der Megakaryozyten bei der primären (idiopathischen) Osteomyelofibrose durch lichtmikroskopische Serienschnitte aus dem Knochenmark vorgestellt. Die erzeugten 3 D-Modelle vermitteln einen plastischen Eindruck von der Komplexität der Zell- und Kernstrukturen dieser Zellen und stellen die Basis für exakte quantitative Analysen der Zellmorphologie dar. Die vorgestellte Technik beinhaltet ein ergänzendes Werkzeug für anatomisch-morphologische Analysen und ist in der Lage, entscheidende Erkenntnisse bei der Untersuchung vielschichtiger histomorphologischer Objekte zu liefern.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Der Pathologe 21 (2000), S. 39-54 
    ISSN: 1432-1963
    Keywords: Schlüsselwörter Chronische myeloische Leukämie ; Megakaryozyten ; Fasern ; Erythropoese ; Makrophagen ; Klinische Befunde ; Immunhistochemie ; Knochenmarkbiopsie ; Key words Chronic myelogenous leukemia ; Megakaryocytes ; Fibers ; Erythroid precursors ; Macrophages ; Clinical findings ; Immunohistochemistry ; Morphometry ; Bone marrow biopsies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary An immunohistochemical and morphometric study was performed on bone marrow biopsies in 604 patients with chronic myelogenous leukemia (CML) to compare morphological and clinical features and to evaluate effects of interferon (IFN) and chemotherapy. Following morphometry significant correlations were calculated between number of CD61+ megakaryocytes, including their precursors with fiber density. This finding is in line with the close functional relationship between megakaryopoiesis and fibroblasts regarding the complex pathomechanism of myelofibrosis. The latter was observed in about 28% of patients already at diagnosis. In a similar way, the frequency of CD68+ macrophages was correlated with the amount of Ret40f+ nucleated erythroid precursors, implicating an involvement of this cell lineage in iron turnover, hemoglobin synthesis, and degradation of the expelled nuclei from normoblasts. The (α-D-galactosyl residue-expressing) Pseudo-Gaucher cells were detectable in 30% of pretreatment specimens. Moreover, significant associations were calculable between reduction in erythropoiesis or increase in fibers with clinical features such as hemoglobin level, percentages of myelo- and erythroblasts in the peripheral blood, and spleen size. These variables are in keeping with more advanced stages of CML. Based on our morphometric evaluations, a classification into three different histological subgroups: granulocytic, megakaryocytic, and myelofibrotic was carried out. This simplified staging system was correlated with corresponding sets of hematological data. Sequential biopsies in 173 patients with monotherapy by IFN, hydroxyurea (HU), or busulfan (BU) revealed a fibrogenic effect of IFN in contrast to a fiber-reducing property of HU. The dynamics of myelofibrosis and changes of major cell lineages during treatment were readily demonstrable by calculating corresponding indices. These included the ratios between quantitative differences of corresponding variables at repeated examinations and time. Thus, in patients with complete hematological remission following IFN administration, regeneration of erythropoiesis was found to be accompanied by an increase in the total number of CD68+ macrophages, including activated subpopulations. Histological subgroups showed a transition from a (nonfibrotic) granulocytic and megakaryocyte pattern to the myelofibrotic subtype in about 40% of patients. This change was opposed to a numerical reduction in the myelofibrotic subtype which occurred in 17 patients (36%), but predominantly in those under HU therapy. In conclusion, the striking heterogeneity of bone marrow features in CML warrants a careful morphological evaluation of trephine biopsies and appropriate means of processing to achieve relevant correlations with clinical data and, thus, allows a more elaborate insight into the dynamics of the disease process.
    Notes: Zusammenfassung Bei 604 Patienten mit einer chronischen myeloischen Leukämie (CML) wurde anhand von Beckenkammbiopsien eine immunhistochemische und morphometrische Studie durchgeführt, um morphologische und klinische Befunde miteinander zu vergleichen und die Auswirkungen der Interferon- (IFN) und Chemotherapie abzuklären. Anhand der morphometrischen Analyse konnten signifikante Korrelationen zwischen der Anzahl CD61+-Megakaryozyten einschließlich ihrer Vorläuferzellen mit der Faserdichte berechnet werden. Dieser Befund spiegelt die enge funktionelle Beziehung zwischen der Megakaryopoese und den Fibroblasten im Hinblick auf den komplexen Pathomechanismus der Myelofibroseentstehung wider. Diese war bei etwa 28% der Patienten bereits zum Diagnosezeitpunkt zu beobachten. In ähnlicher Weise war die Anzahl der CD68+-Makrophagen mit der Menge an Ret40f+-kernhaltigen erythropoetischen Vorläuferzellen korreliert, was durch die Einbindung dieser Zellinie in den Eisenstoffwechsel, die Hämoglobinsynthese sowie den Abbau der ausgestoßenen Normoblastenkerne in Zusammenhang gebracht werden kann. Die (α-D-Galaktosylreste-expremierende) Pseudo-Gaucherzellen ließen sich in 30% der Biopsien vor Behandlung nachweisen. Weiterhin konnten signifikante Beziehungen zwischen einer Reduktion der Erythropoese oder einer Zunahme der Verfaserung mit klinischen Parametern wie dem Hämoglobinspiegel, dem Anteil an Myelo- und Erythro-Normoblasten im peripheren Blut und der Milzgröße berechnet werden. Diese Variablen kennzeichnen offensichtlich mehr fortgeschrittene Stadien der CML. Entsprechend unserer morphometrischen Auswertung wurde eine Klassifikation in drei unterschiedliche histologische Subgruppen vorgenommen: granulozytisch, megakaryozytisch und myelofibrotisch. Dieser vereinfachten histologischen Einteilung waren entsprechende hämatologische Daten zuzuordnen. Sequenzbiopsien an 173 Patienten, die eine Monotherapie mit IFN, Hydroxyurea (HU) oder Busulfan (BU) erhielten, zeigten einen fibrogenetischen Effekt von IFN im Gegensatz zu einer eher faserreduzierenden Eigenschaft von HU. Die Dynamik der Myelofibroseentwicklung und die entsprechende Veränderungen der hauptsächlichen Zellinien während der Behandlung ließen sich am besten durch eine Kalkulation von Indizes verdeutlichen. Diese beinhalteten das Verhältnis aus quantitativen Unterschieden der einzelnen Variablen in den wiederholt durchgeführten Entnahmen und den zugeordneten zeitlichen Differenzen. So war bei Patienten mit einer kompletten hämatologischen Remission nach IFN-Gabe die Regeneration der Erythropoese zusammen mit einem Anstieg in der Anzahl CD68+-Makrophagen einschließlich ihrer aktivierten Subpopulation auszumachen. Die histologischen Subgruppen ließen bei fortlaufenden Untersuchungen einen Übergang sowohl von einem (nicht verfaserten) granulozytären wie auch megakaryozytären Subtyp in eine myelofibrotische Gruppe bei etwa 40% der Patienten erkennen. Dieses Phänomen stand im Gegensatz zu einer anzahlmäßigen Reduzierung des myelofibrotischen Typs vor allem bei Patienten unter HU-Therapie in 17 Fällen (36%). Zusammengefaßt erfordert die auffallende Heterogenität der Knochenmarkbefunde bei der CML eine sorgfältige morphologische Auswertung von Biopsien mit geeigneten Methoden, um relevante Korrelationen zwischen klinischen Daten zu berechnen und somit einen besseren Einblick in die Dynamik der Krankheitsentwicklung zu gewinnen.
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  • 6
    ISSN: 1432-0584
    Keywords: Key words Chronic myeloproliferative disorders ; Erythroid precursors ; Neutrophil granulopoiesis ; Megakaryocytes ; Macrophages ; Myelofibrosis ; Enzyme-immunohistochemistry ; Morphometry ; Bone marrow biopsy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The aim of this review is to evaluate morphological characteristics of the different subtypes of chronic myeloproliferative disorders (MPDs) derived by applying immunohistochemical and morphometric techniques to bone marrow biopsies and to combine these results with relevant clinical parameters. In comparison to control specimens, a significant decrease in erythroid precursors is determinable in chronic myeloid leukemia (CML), while this cell lineage is most prominent in polycythemia vera (PV) and moderately to markedly reduced in idiopathic myelofibrosis (IMF). On the other hand, neutrophilic granulopoiesis shows a predominance in CML and a relevant increase in PV, but no conspicuous changes are detectable in essential thrombocythemia (ET). CML is characterized by a prevalent growth of dwarflike micromegakaryocytes, occurring in particular in the so-called megakaryocyte-rich subtypes (about 30%). This finding differs significantly from the pleomorphous aspect, i.e., clusters of small to giant-sized megakaryocytes in PV and the grossly abnormal (dysplastic) appearance of this cell lineage in patients with IMF. Similar cytological abnormalities of megakaryopoiesis consistent with maturation defects are never encountered in ET. The incidence of mature (resident) macrophages (phagocytic reticular cells) is significantly enhanced in IMF in comparison to the other MPDs and controls. Moreover, there is a striking difference in the density of reticulin-collagen fibers, ranging from normal (ET) to extreme values (IMF). In IMF more than 80% of the patients present with some degree of myelofibrosis-osteosclerosis at diagnosis, while the rest show an initial prefibrotic, hypercellular stage. This feature deserves special attention since, when accompanied by thrombocythemia, it may simulate ET. Sequential bone marrow biopsies in patients with IMF disclose that evolution of myelofibrosis is progressive, but occurs at a variable and unpredictable speed. A synoptical approach regarding clinical diagnosis and histological subtyping of MPDs is explicitly recommended and demonstrated by sets of diagnostic criteria. This rationale requires equal consideration of laboratory data and morphology by clinicians to include well-defined subtypes of MPDs into prospective management studies. Furthermore, it may even warrant follow-up studies and repeated bone marrow examinations in initially unclassifiable cases.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Annals of hematology 38 (1979), S. 407-420 
    ISSN: 1432-0584
    Keywords: Polycythämia vera ; Ultrastruktur des Knochenmarkes ; Kernspalten ; Mikromegakaryozyten ; myeloproliferative Erkrankungen ; Polycythemia vera ; Bone marrow ultrastructure ; Nuclear clefts ; Micromegakaryocytes ; Myeloproliferative disorders
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Electron microscopy (thin sections and freeze-fracture replicas) was performed on the bone marrow of ten patients with Polycythemia vera prior to any treatment. In addition to a hyperplasia of all three cell lineages and the sinuses, atypias were observed in the maturing erythroblasts. These aberrations of normal development consisted mainly of deep invaginations of the nuclear envelope in proerythroblasts and conspicuous nuclear clefts in erythro- and normoblasts. In comparison with similar changes in dyserythropoietic and aplastic anemia as well as leukemia these alterations are discussed in connection with disturbances of DNA synthesis. Further atypias involved megakaryopoiesis which displayed microforms probably as an evidence for maturation arrest. These ultrastructural abnormalities with their morphological features of a neoplastic proliferation of all three cell lineages in Polycythemia vera are in good agreement with the new concept of a transformation of a pluripotent stem cell with clonal character.
    Notes: Zusammenfassung Elektronenmikroskopische Untersuchungen (Dünnschnitte und Gefrierbrechungen) wurden am Knochenmark von zehn Patienten mit Polycythämia vera vor der Behandlung durchgeführt. Au\er der Hyperplasie aller drei Zellreihen und der Sinus wurden vor allem Atypien der reifenden Erythroblasten gesehen. Diese Abweichungen der normalen Entwicklung bestanden hauptsächlich aus tiefen Einstülpungen der Kernhülle im Proerythroblasten und in auffallenden Kernspalten in Erythro- und Normoblasten. Im Vergleich zu ähnlichen Veränderungen bei dyserythropoetischen und aplastischen Anämien ebenso wie bei Leukämien werden diese Anomalien im Zusammenhang mit Störungen der DNA-Synthese diskutiert. Weitere Atypien betrafen die granulocytäre Reihe mit abnormen Kernschleifen und die Megakaryopoese, die Mikroformen aufwies, was wohl als ein Ausdruck der Reifungshemmung zu werten ist. Diese ultrastrukturellen Anomalien mit ihren morphologischen Kriterien der neoplastischen Proliferation aller drei Zellreihen bei der Polycythämia vera passen gut in das neue Konzept der Transformation einer pluripotenten Stammzelle mit klonalem Charakter.
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  • 8
    ISSN: 1432-0584
    Keywords: CML ; Myelofibrosis ; Dynamics ; Megakaryocytes ; Morphometry ; Interferon ; Busulfan ; Sequential bone marrow biopsies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To evaluate treatment-related changes of the reticulin stain-measured fibrosis in Ph1+-CML, a clinicopathological study was performed on sequential trephine biopsies of the bone marrow following either interferon (IFN) or busulfan (BU) monotherapy. Using the monoclonal antibody CD61 for the identification of megakaryopoiesis and Gomori's silver impregnation method, number of megakaryocytes and density of argyrophilic (reticulin and collagen) fibers were determined by morphometry. We studied specimens from 26 patients with IFN-alpha 2b (including nine patients with additional IFN gamma) therapy and from 23 patients who had received BU. In both groups, repeated bone marrow biopsies (total 125) revealed a significant increase in the fiber content, as well as in the number of megakaryocytes during treatment. To assess the dynamics of myelofibrosis more precisely, computation of differences in the degree of fiber density between the first and last examination was carried out. Regarding the considerable variations in the biopsy intervals, a so-called myelofibrosis progression index (MPI) was calculated. Following this rationale, we were able to demonstrate that, in comparison to the BU-group, speed of progression of bone marrow fibrosis was significantly increased in CML patients treated with IFN. Preliminary statistical analysis indicated a relationship between myelofibrosis on admission, which was always associated with increased growth of megakaryocytes, and the MPI with survival. Even when these parameters were regarded, prognosis was significantly more favorable in the IFN-treated patients. The failure of IFN and BU to inhibit the evolution of myelofibrosis may be related to several conversely acting pathomechanisms. Among others, the inability of both therapeutic agents to reduce the number of megakaryocytes more effectively should be taken into consideration.
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  • 9
    ISSN: 1432-0584
    Keywords: Key words CML ; Myelofibrosis ; Dynamics ; Megakaryocytes ; Morphometry ; Interferon ; Busulfan ; Sequential bone marrow biopsies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  To evaluate treatment-related changes of the reticulin stain-measured fibrosis in Ph1+-CML, a clinicopathological study was performed on sequential trephine biopsies of the bone marrow following either interferon (IFN) or busulfan (BU) monotherapy. Using the monoclonal antibody CD61 for the identification of megakaryopoiesis and Gomori's silver impregnation method, number of megakaryocytes and density of argyrophilic (reticulin and collagen) fibers were determined by morphometry. We studied specimens from 26 patients with IFN-alpha 2b (including nine patients with additional IFN gamma) therapy and from 23 patients who had received BU. In both groups, repeated bone marrow biopsies (total 125) revealed a significant increase in the fiber content, as well as in the number of megakaryocytes during treatment. To assess the dynamics of myelofibrosis more precisely, computation of differences in the degree of fiber density between the first and last examination was carried out. Regarding the considerable variations in the biopsy intervals, a so-called myelofibrosis progression index (MPI) was calculated. Following this rationale, we were able to demonstrate that, in comparison to the BU-group, speed of progression of bone marrow fibrosis was significantly increased in CML patients treated with IFN. Preliminary statistical analysis indicated a relationship between myelofibrosis on admission, which was always associated with increased growth of megakaryocytes, and the MPI with survival. Even when these parameters were regarded, prognosis was significantly more favorable in the IFN-treated patients. The failure of IFN and BU to inhibit the evolution of myelofibrosis may be related to several conversely acting pathomechanisms. Among others, the inability of both therapeutic agents to reduce the number of megakaryocytes more effectively should be taken into consideration.
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  • 10
    ISSN: 1432-0584
    Keywords: Key words Apoptosis ; PCNA-labeling ; Idiopathic thrombocytopenia ; Polyglobuly ; Reactive thrombocytosis ; Primary thrombocythemia ; Polycythemia vera ; AML ; Hematopoietic turnover index ; Bone marrow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics.
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