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Poor prognosis associated with thrombocytosis in patients with renal cell carcinoma.

OBJECTIVES: To better define the relationship between platelet count and survival using a retrospective analysis in patients with thrombocytosis and metastatic renal cell carcinoma (RCC), some of whom had a shorter life expectancy than those with a normal platelet count. PATIENTS AND METHODS: The records were reviewed of patients with stage IV RCC who had undergone a variety of adjuvant therapies after nephrectomy between 1972 and 1992. Entry criteria included a tissue diagnosis of RCC, at least one platelet count and a complete follow-up until the time of death. Of 350 patients available for review, 259 met the entry criteria. Patients were divided into two groups: group 1 included 112 patients whose platelet counts remained at < 4 x 105/microL between the time of nephrectomy and the time of death; group 2 included 147 patients with at least one platelet count of > 4 x 105/microL (mean age in each group 57 years). RESULTS: The mean (SD) survival for group 1 was 151 (34) months, compared with 92 (18) months for those in group 2. Using the log-rank chi-square test the difference in survival between the groups was significant (P = 0.005). Controlling for established prognostic indicators of pathological stage, nuclear grade and cell type, using Cox's regression technique, the difference in survival between the groups remained significant (P = 0.015). CONCLUSIONS: These results suggest that patients with metastatic RCC who receive adjuvant therapy and have a persistently normal platelet count have a 64% longer life expectancy than those with thrombocytosis. The difference is highly statistically significant when controlled for nuclear grade, cell type and pathological stage.

Carcinoma, Renal Cell↗

Familial urticaria pigmentosa associated with thrombocytosis as the initial symptom of systemic mastocytosis and Down's syndrome.

Most cases of urticaria pigmentosa are confined to the skin, but visceral involvement and/or haematological abnormalities have been observed. It is still a matter of debate whether all forms of mastocytosis are true neoplasias or reactive hyperplasias. Familial inheritance of urticaria pigmentosa is rare. We report on a fraternal set with urticaria pigmentosa as part of a systemic mastocytosis. The first patient additionally revealed persistent thrombocytosis and splenomegaly. His brother developed urticaria pigmentosa, intermittent diarrhoea, hepatomegaly and asthma bronchiale associated with trisomy 21 (Down's syndrome). The association of mastocytosis with thrombocytosis has seldom been described. In our patient it preceded the development of systemic mastocytosis. The association with Down's syndrome has not been reported until now.

Biopsy, Needle↗

Rapid reduction of platelet numbers in thrombocytosis.

Thrombocytosis has been reported during chemotherapy with gemcitabine (GEM). A 71-year-old male patient who developed asymptomatic thrombocytosis (1,749 x 10(3)/microl), secondary to GEM chemotherapy for lung carcinoma, was submitted to therapeutic plateletpheresis (TP). We adapted the software of the productive dual-needle plateletpheresis of our cell separator in order to reduce the procedure time and the plasma volume harvested. With 2 low-volume TP in 24 h, we achieved a 55% global reduction of the platelet count. While there are no accepted indications for prophylactic plateletpheresis in asymptomatic patients and the measured count should not, by itself, determine whether platelet reduction is indicated, a drastic reduction of an extremely high platelet count, especially if obtained with a relatively short procedure, can be important to prevent acute severe sequelae.

Aged↗

Long-term plateletpheresis in the management of primary thrombocytosis.

We attempted to control the platelet count of a patient with primary thrombocytosis utilizing long-term plateletpheresis therapy. The patient previously could not be controlled with chemotherapy, because of rapid development of leukopenia. Although intensive pheresis at the rate of four to five procedures per week produced rapid lowering of the patient's platelet count, continued therapy at the rate of two to three procedures a week failed to maintain these counts, and platelets gradually rose to pretreatment levels. We conclude that while plateletpheresis can produce acute lowering of elevated platelet counts, the rate of platelet production in primary thrombocytosis may be too rapid to allow for long-term control by pheresis alone, utilizing an acceptable treatment schedule of one of three procedures per week.

Blood Transfusion↗

Sideroblastic anaemia with reactive thrombocytosis versus myelodysplastic/myeloproliferative disease.

The reported incidence of thrombocytosis among cases of refractory anaemia with ring sideroblasts (RARS) may be as high as 15%. We report four additional cases of this association, which appear to be hematologically heterogeneous. One patient clearly represents a case of RARS with reactive thrombocytosis. Two cases have features suggestive of the coincidental occurrence of essential thrombocythemia and RARS. The fourth case could be best classified as a subtype of myelodysplastic/myeloproliferative disease unclassifiable (MDS/MPD U). Only new biological or molecular markers will allow better differentiation between these disorders.

Aged↗

Plasma heparin neutralizing activity. Its use in the evaluation of thrombocytopenia and thrombocytosis.

Platelets contain heparin neutralizing activity, which is released into plasma following aggregation. This material is probably identical to platelet factor 4. We describe a technic to measure heparin neutralizing activity in platelet-poor plasma based on the serial heparin dilution technic of Harada and Zucker. Heparin neutralizing activity was depressed in thrombocytopenia due to immune thrombocytopenia and bone marrow depression, and elevated in thrombocytopenia due to disseminated intravascular coagulation. Secondary thrombocytosis is characterized by markedly elevated heparin neutralizing activity, while thrombocytosis associated with myeloproliferative disorders has normal heparin neutralizing activity.

Blood Coagulation Factors↗

Platelet parameters and aggregation in essential and reactive thrombocytosis.

Platelet characteristics were assessed in 15 patients with essential thrombocytosis (ET), 89 patients with reactive thrombocytosis (RT), and 23 normal controls. A platelet volume distribution width (PDW) greater than or equal to 10.5 was found in 50%, 21%, and 14% of the three groups, respectively (P = 0.01 between patients with ET and patients with RT; P = 0.02 between patients with RT and controls), reflecting an excess of extreme values at both ends of the distribution. Compared with controls, the increase in platelet number in patients with RT was about twofold throughout the platelet volume range, whereas ET was characterized by a fivefold increase in small platelets less than 7.5 fL and threefold increase in larger size platelets. Mean platelet volume (MPV) was significantly lower in patients with ET versus patients with RT and in patients with RT versus controls (mean +/- SD 7.5 +/- 1.2 vs. 8.8 +/- 0.1 and 10.2 +/- 1.8 fL, respectively, P less than 0.01). Rate of in vitro platelet aggregation greater than or equal to 50% was significantly lower in patients with ET versus patients with RT and in patients with RT versus controls (0%, 23%, and 45%, respectively, P less than 0.01). Aggregation rate was positively correlated with MPV (r = 0.54; P less than 0.0001). Aggregation rate in patients with ET was significantly lower (P = 0.01) than expected from their reduced MPV alone. Despite these group differences, the overlap of individual platelet characteristics between the three groups precludes their usefulness for diagnostic purposes.

Adenosine Diphosphate↗

The clinical spectrum of thrombocytosis and thrombocythemia.

Platelet production is the result of a highly ordered maturation of a developmental hierarchy of megakaryocytic progenitor cells regulated by a variety of cytokines. GM-CSF, II-3 and II-6 have a stimulatory effect and several cytokines (TGF-beta, platelet released glycoprotein, platelet factor 4 and interferons) have inhibitory effects down regulating platelet production perhaps as part of an autocrine control loop. Excess platelet production can be clinically characterized as pseudothrombocytosis, thrombocytosis or thrombocythemia; the clinical features and criteria for each are defined. The term thrombocytosis infers its reactive nature and, in the absence of arterial disease or prolonged immobility, it poses little risk regardless of platelet numbers. By contrast, in thrombocythemia, whether primary or associated with other myeloproliferative lesions, significant thrombohemorrhagic events occur. The natural history, rationale, and approach to platelet reduction and control of clinical sequela are reviewed. Clinical therapeutic options include a new agent, Anagrelide.

Blood Platelets↗

Use of a radioimmunoassay for 5-hydroxytryptamine (5-HT) in thrombocytosis.

A decrease in intra-platelet 5-hydroxytryptamine (5-HT) may be a possible marker for primary thrombocytosis and there are several different methods for the measurement of platelet 5-HT content (e.g. fluorimetry, high-performance liquid chromatography and radioimmunoassay). The present study has shown that, in laboratories with radioprotected areas, radioimmunoassay of 5-HT is a simple method which correlates well with a standard fluorimetric technique and yields satisfactory results in patients with thrombocytosis.

Adult↗

Profound thrombocytosis in a patient with iron-lack anemia.

Platelet counts in excess of 1 million/cu mm are generally associated with a primary hematologic disorder such as a myeloproliferative syndrome. We describe a patient whose thrombocytosis (platelet count 1.6 million) was due solely to iron lack, and whose platelet count rapidly returned to normal with iron repletion. Clinicians are encouraged to consider reactive causes of thrombocytosis when evaluating platelet counts in excess of 1 million.

Anemia, Hypochromic↗

Reactive thrombocytosis: an early manifestation of Takayasu arteritis.

A woman with Takayasu arteritis is reported who presented with constitutional symptoms and persistent thrombocytosis documented since 3 years before the diagnosis. Disease-specific symptoms such as arm claudication, transient loss of vision, and self-remitting eye ptosis present at the time were apparently missed, because she is a non-English-speaking Hispanic woman whose history was obtained through an interpreter. Extensive workup done at the time failed to reach a definite etiology. A computed tomography scan of the chest done because of midthoracic back pain and an elevated erythrocyte sedimentation rate showed circumferential wall thickening and mild surrounding edema throughout the thoracic and abdominal aorta and both carotid arteries consistent with Takayasu arteritis. Prednisone at a dosage of 1 mg/kg twice a day decreased the platelet count within 45 days of its initiation. Takayasu arteritis should be considered in the differential diagnosis of unexplained thrombocytosis, particularly in young women.

Adult↗

Paraneoplastic syndromes of leukocytosis, thrombocytosis, and hypercalcemia associated with squamous cell carcinoma.

Paraneoplastic syndromes including leukocytosis, thrombocytosis and hypercalcemia are occasionally seen in patients suffering from progressive malignant disorders. Recent studies have revealed the production of several humoral factors by tumor cells and normal splenic cells of tumor-bearing patients to be the major cause of these reactions. Granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte-colony stimulating factor (G-CSF), parathyroid hormone-related peptide, interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF) have been implicated. We describe a 58-year-old Japanese man with squamous cell carcinoma (SCC) on the left sole, which developed in a deep linear scar after a train crash. He developed pulmonary and lymph node metastases, then leukocytosis (57,110/mm3 with 95% neutrophilia), thrombocytosis (86.3 x 10(4)/mm3), and hypercalcemia (7.0 mEq/1), and finally cachexia, followed by death. Serum G-CSF, IL-1 alpha, IL-1 beta, and TNF-beta were determined; revealing G-CSF and IL-1 beta levels were above the upper limits of their normal ranges at 39.2 pg/ml and 4.63 pg/ml, respectively. It is probable that these humoral factors were partially responsible for the paraneoplastic syndromes induced by the cutaneous SCC with metastasis in the present case.

Animals↗

Platelet membrane glycoprotein abnormalities in patients with myeloproliferative disorders and secondary thrombocytosis.

Carbohydrate-specific surface labelling and 125I-labelled lectin binding techniques, in combination with one- or two-dimensional (non-reduced/reduced) SDS-polyacrylamide gel electrophoresis have been used with platelets from patients with myeloproliferation disorders and secondary thrombocytosis and from healthy donors. In essential thrombocythaemia platelet membrane glycoproteins were significantly less sialylated than in normals (particularly GP Ib and IIIa). Increased binding of 125I-labelled Lens culinaris lectin to thrombospondin and GP IIIa indicated a defect in the glucose/mannose glycosylation of the platelet glycoproteins in essential thrombocythaemia. In polycythaemia vera and in chronic myeloid leukaemia the terminal sialic acid of glycoprotein IIIb was labelled slightly more than normal. In chronic myeloid leukaemia there was increased labelling of the penultimate galactose/N-acetylgalactosamine residues of GP Ib, IIb, IIIa and IIIb. In comparison to myeloproliferative disorders, platelets from patients with secondary thrombocytosis showed no significant changes, except for platelets from two patients with idiopathic thrombocytopenic purpura which showed an increased sialylation of all surface glycoproteins.

Blood Platelets↗

Interferon alpha-2b as treatment for Philadelphia-negative chronic myeloproliferative disorders with excessive thrombocytosis.

We treated 32 patients with Ph1-negative chronic myeloproliferative disorders (CMD) with excessive thrombocytosis with Interferon alpha-2b (IFN alpha-2b): 26 had essential thrombocythaemia, ET (18 previously untreated, eight pretreated); one thrombocythaemia after treatment for Hodgkin's disease (HD); two thrombocythaemia associated with non-Hodgkin's lymphoma (NHL); three stage II idiopathic myelofibrosis (IM). IFN was given at daily doses of 1-4 x 10(6) IU. Twenty-seven patients (84%) responded, 17 (53%) achieved complete haematologic response after a median time of 12 weeks, and 10 (31%) partial haematologic response. Median platelet levels declined in complete haematologic response patients from 1,190 to 335 x 10(9)/l. Normalization of megakaryocyte (MK) levels was observed in 8/17 complete haematologic response patients treated for 9-12 months, with decreased bone marrow (BM) cellularity. Side effects requiring dose reduction or discontinuation of treatment occurred in 28% of cases with IFN doses of 2 or 4 x 10(6) IU. After 1 year of continuous IFN treatment, responses were maintained with conventional chemotherapy or low-dose IFN. This study demonstrates that IFN has definite therapeutic activity in CMD with excessive thrombocytosis. This biological agent, either alone or in combination with other antineoplastic treatment, may represent a new therapeutic approach for these disorders.

Adult↗

Interferon-alpha-induced morphological changes of megakaryocytes: a histomorphometrical study on bone marrow biopsies in chronic myeloproliferative disorders with excessive thrombocytosis.

Interferon(rIFN)-alpha, a successful therapeutic agent in the control of thrombocytosis, has been shown to suppress human megakaryopoiesis. We investigated bone marrow biopsies from 12 patients with thrombocytosis due to chronic myeloproliferative disorders. Prior to treatment as well as during rIFN-alpha-2c therapy, several morphometric parameters of megakaryopoiesis were evaluated. Megakaryocyte density decreased significantly in all patients, megakaryocyte size decreased in polycythaemia vera, agnogenic myeloid metaplasia, and essential thrombocythaemia, but increased in chronic myeloid leukaemia. The various changes observed during therapy indicate an inhibitory effect of rIFN-alpha-2c on megakaryopoiesis and suggest a selective influence on megakaryocytes at various stages of maturation. Increased numbers of pyknotic (bare) nuclei may reflect a shortening of megakaryocyte life-span. No remarkable changes were found in the fibre content of the bone marrow.

Aged↗

Variable expression of features of normal and neoplastic stem cells in patients with thrombocytosis.

Essential thrombocytosis (ET) is currently diagnosed by histopathologic assessment of the marrow after exclusion of a secondary cause or another myeloproliferative disorder. To evaluate the potential of more direct diagnostic methods, we compared the frequency and association of several abnormal features characteristic of neoplastic precursors in 32 patients presenting with platelet counts > 500 x 10(9)/l. Assays for erythropoietin (Ep)-independent erythroid progenitors were performed on all patients, determination of the cycling status of circulating progenitors on 27, and assessment of granulocyte clonality on 15. In most, but not all, patients deregulated progenitor turnover. Ep-independent progenitors and clonal granulocytes were concordant findings. The presence of polyclonal granulocytes and lack of evidence of abnormalities in Ep-dependence or progenitor cycling were also concordant findings in most, but not all patients. Thus, normal (i.e. polyclonal) granulocytes may be produced in occasional patients in spite of the presence of a neoplastic clone. Interestingly, one third of patients thought to have ET on the basis of blood and marrow histopathology showed no abnormalities previously associated with neoplastic progenitors. These findings suggest variability in dominance of the neoplastic clone in some ET patients and the potential utility of a multifaceted laboratory approach to investigate the underlying pathology in patients with thrombocytosis.

Adult↗

Familial thrombocytosis.

Four cases of thrombocytosis in three successive generations of a family are described. High peripheral platelet count was found incidentally in the proband with cutaneous malignant lymphoma. Bone marrow examination showed megakaryocytic hyperplasia. Neither Philadelphia chromosome nor chimaeric bcr/abl junction was detected in marrow cells. In this family, thrombocytosis was thought to be transmitted by an autosomal dominant mode of inheritance.

Child, Preschool↗

Altered platelet phospholipid-dependent thrombin generation in thrombocytopenia and thrombocytosis.

Platelet phospholipid dependent thrombin generation was determined in 20 patients with thrombocytosis, 18 with thrombocytopenia, and 25 normal controls, using a quantitative chromogenic assay. Platelets from patients with myeloproliferative disorders displayed normal lag times to 20 nM thrombin concentration but increased thrombin potentials, even when corrected for platelet size. Platelets from patients with reactive thrombocytosis supported normal thrombin generation. ITP platelets were large, with a proportionate increase in thrombin potentials, but very short lag times to 20 nM thrombin concentration. Following marrow ablation there was a progressive loss of activation-induced enhancement of thrombin generation. Platelets from patients with idiopathic aplastic anaemia supported normal thrombin generation. These findings indicate that platelet phospholipid-dependent thrombin generation is altered in many patients with a variety of quantitative platelet disorders, and this may be an important determinant of the clinical expression of these disorders.

Anemia, Aplastic↗