1/8. light and electron microscopic studies of the bone marrow and blood cells in chronic panmyelosis including polycythemia vera and primary thrombocythemia.Both bone marrow and peripheral blood was investigated light and electron microscopically in 3 cases with polycythemia vera, 2 cases with primary thrombocythemia and 1 case with panmyelosis. In 5 cases the peripheral blood showed persistent increase in cells of two or three hematopoietic systems. Giant thrombocytes in the peripheral blood were seen in 3 cases. erythroblasts, granulocytic young forms, and megakaryocytes were often observed in the blood. Histologic bone marrow examination showed prominent proliferation of all 3 hematopoietic cells in every case. Cytological and electron microscopical examinations of the bone marrow revealed many mitotic figures, morphological abnormalities, and unbalanced nucleocytoplasmic maturation in various hematopoietic cells. These findings suggested that the proliferation of all 3 hematopoietic cells in the bone marrow was not simply reactive in nature, but an idiopathic progressive process. It is considered that these disorders and primary myelosclerosis represent no separate entities and must be unified as "chronic panmyelosis".- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/8. Chronic myelogenous leukemia.Chronic myelogenous leukemia (CML) is a relatively rare disease, with a number of features that make it especially suitable for observations on leukemogenesis in man. These include known etiologic agents, often a prolonged preclinical and active stage, cells with identifiable morphological and histochemical characteristics and the presence of the unique Ph' chromosome. The transition of CML to blast crisis is a catastrophic event; however, recent clinical and biochemical studies have raised important questions as to the nature and origin of blast cells in this disease. During the past 10 years, we have followed 113 cases olf CML throughout their course and results of observations on the clinical, hematological and other apsects of the disease are presented in this communication.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/8. Characterization of the blast cell population in two neonates with Down's syndrome and transient myeloproliferative disorder.The phenotype and in vitro growth properties of blood and marrow blast cells detected in two neonates with Down's syndrome and a transient leukaemic picture are presented. In both patients, blast cells at diagnosis were heterogeneous and expressed predominantly megakaryocyte and erythroid markers identified by membrane fluorescence using monoclonal antibodies or ultrastructural detection of platelet peroxidase and ferritin. An additional trisomy involving chromosome 22 was detected in blast cells from one patient. Blood and marrow cells colony-assays performed at diagnosis revealed precursors with an abnormal differentiation capacity similar to those found in acute myelogenous leukaemia colony assays. However, an unusual feature was the persistence of high numbers of precursor cells (namely erythroid) following a normal differentiation pathway. Phenotypically and cytogenetically abnormal cells spontaneously disappeared by week 4-6, but overt relapse occurred in one patient 20 months later. These results bring strong arguments in favour of the neoplastic nature of the transient leukaemic picture observed in some neonates with Down's syndrome. Furthermore, we suggest that this disorder can be individualized as a separate entity with specific phenotypic and biological properties.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/8. Frequent association of idiopathic myelofibrosis with plasma cell dyscrasias.In a retrospective analysis of 199 cases of myeloproliferative diseases a concomitant plasma cell dyscrasia was found in three out of 46 patients with idiopathic myelofibrosis. Chronic myeloid leukemia, polycythemia vera or unclassifiable myeloproliferative disorders were in no case associated with monoclonal gammopathy. One patient with idiopathic myelofibrosis had primarily coexistent IgG-lambda paraproteinemia and increasing osteolytic lesions; histologic evidence of multiple myeloma, however, was insufficient. In the second patient the interval between diagnosis of idiopathic myelofibrosis and IgG-kappa paraproteinemia was 11 years. After a stable period of 9 years' duration the paraprotein level rapidly increased, associated with depression of normal background immunoglobulins and progressive bone marrow failure. The exact nature of this patient's malignant plasma cell dyscrasia remained uncertain. In the third case benign monoclonal gammopathy of the IgM-lambda type was diagnosed 13 years after idiopathic myelofibrosis. A review of the literature confirms a remarkably high incidence of monoclonal gammopathies in idiopathic myelofibrosis. Benign monoclonal gammopathy seems to occur in at least 8% of the patients while only a few cases of concomitant multiple myeloma have been reported. It may be speculated that plasma cell dyscrasias in idiopathic myelofibrosis reflect involvement of the lymphoid lineage in the neoplastic stem cell disorder.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/8. The occurrence of an auto-immune hemolytic anemia with anti-U specificity in a patient with myelodysplastic syndrome.A 73-year-old man with myelodysplastic syndrome developed during the course of his illness auto-immune hemolytic anemia. The association between auto-immune hemolysis and myeloproliferative disease is extremely rare. An even more unique finding is the nature of the antibody which demonstrated single specificity against the U antigen.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/8. Acquired haemoglobin H disease, complicating a myeloproliferative syndrome: a case report.A case of acquired haemoglobin H disease in association with a myeloproliferative disorder is described. Severe haemolysis with hypochromic microcytic anaemia was present. Haemoglobin H formed 18% of the circulating haemoglobin and 60% of the red cells showed multiple inclusions on incubation with brilliant cresyl blue. Blood film and absolute red cell values from a previous unrelated illness were normal, proving the acquired nature of the haemoglobin abnormality. Alpha/beta chain synthesis was measured in vitro and the degree of imbalance (alpha/beta ratio 0.39) was similar to that seen in the inborn thalassaemic disorder. A small proportion of red cells showed i-antigen reactivity but their haemoglobin H content was no different from the majority of cells which were l-antigen positive.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/8. Spontaneous loss of Ph chromosome with maintenance of clonal hemopoiesis in an untreated patient with myeloproliferative disease and a long survival.The unusual case of myeloproliferative disease described here is characterized by the following features: (1) a clinically completely silent course for 11 years without splenomegaly, marrow fibrosis, or cellular morphologic alterations; (2) the presence, at the onset, of a philadelphia (Ph) chromosome without dna breakpoints in the M-bcr region; (3) the spontaneous loss of detectable Ph-positive cells, 5 years after the first finding of leukocytosis, in the absence of any therapy; (4) the maintenance of the clonal nature of hematopoiesis, as revealed by the PGK X-linked inactivation pattern, in the absence of the Ph chromosome; and (5) a biphasic trend in the levels of leukocytes, red cells, and platelets during the years of observation.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/8. Ultrastructure of unusual cytoplasmic inclusions in a case of myeloproliferative disorder.An unusual case of myeloproliferative disorder in which mature and immature myeloid cells were found to contain unusual cytoplasmic inclusions is reported. By light microscopy, these inclusions could be observed with Wright's stain. By electron microscopy they appeared to consist of a pale, finely granular material without surrounding membranes. Although their exact nature remains unknown, we speculate that they may represent the results or products of autophagocytosis of a portion of degenerated cytoplasm.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |