bl-4162a and Hemorrhagic-Disorders

Essential thrombocythemia must now be regarded as a heterogeneous disease. Recent availability of clonality studies have repeatedly shown that a significant number of female patients diagnosed as E.T. according the most stringent criteria had a definitely polyclonal myelopoiesis. Although the incidence of patients newly diagnosed every year is low, there is in fact a conspicuous population of E.T., followed as outpatients in every department of hematology or internal medicine, including a large number of young females. These eventualities should be integrated in further discussions of the benefit/risk ratio of cytoreduction with the presently available drugs. The combination of several evidence-based data is the basis of a widely accepted stratification of high-risk patients defined by any of the following features. Age > 60 to 65. History of thrombosis or embolic or major ischemic events. Platelet counts in excess of 1000 or 1500 x 10(9)/L. In the question of chemotherapy in E.T., growing concern comes from the potential leukemogenic risk associated with the presently available drugs and extends beyond Melphalan, Busulfan and other alkylating agents and includes non-alkylating agents like Hydroxyurea. At the same time, much attention has been paid to the introduction of very precise initial diagnostic criteria directed to elimination of other myeloproliferative or myelodysplastic disorders with an increased risk of transformation. Present treatment of E.T. is a compromise between prevention of E.T. related thrombotic and bleeding complications on one hand and long term side effects and toxicity of the presently available drugs on the other hand. The recent availability of non mutagenic drugs like Interferon and most of all Anagrelide; the recognition of the role of antiaggregating agents in the treatment of platelet related microvascular ischemic events gives the opportunity for further comparative prospective trials. The use of aspirin in the management of pregnant E.T. patients is now widely accepted but there is still controversies concerning the use of Interferon in this situation.

Topics: Adult; Aged; Aspirin; Case Management; Clinical Trials as Topic; Diagnosis, Differential; Disease Progression; Female; Hemorrhagic Disorders; Humans; Hydroxyurea; Interferons; Leukemia; Male; Middle Aged; Pipobroman; Platelet Aggregation Inhibitors; Platelet Count; Pregnancy; Pregnancy Complications, Hematologic; Prospective Studies; Quinazolines; Risk; Safety; Thrombocythemia, Essential; Thrombophilia

Evidences suggest an association between leukocytosis and thrombotic or hemorrhagic complication in polycythemia vera (PV) and essential thrombocythemia (ET), but clinical implication is not well known.. To evaluate whether leukocyte burden during follow-up is related to thrombotic or hemorrhagic events in PV and ET.. We retrospectively analyzed patients with PV or ET treated at Seoul National University Bundang Hospital, Korea. Time-weighted averages of leukocytes during the follow-up period were defined as leukocyte burden and were calculated for each patient and compared between patient subgroups. In each patient with events, leukocyte burden for the 3-month period before the event was compared with that for the entire follow-up period.. In 102 patients with PV or ET, 35 events (16 thrombotic, 19 hemorrhagic) occurred in 29 patients (median follow-up, 54months). Leukocyte burden were significantly higher in patients with events than in event-free patients (12,015×10(3) /μL vs. 9,567×10(3)/μL, P=0.003). The difference was more prominent in ET patients than in PV patients, and in patients with hemorrhagic events than in those with thrombotic events. In patients with events, the leukocyte burden in the pre-event period was higher than in the entire follow-up period (16,767×10(3)/μL vs. 12,015×10(3)/μL, P=0.002). In all patients, leukocyte burden during entire follow-up period of 11,000×10(3)/μL or higher was an independent risk factor for vascular events.. In PV or ET patients, leukocyte burden during disease course is related to increased incidence of thrombotic or hemorrhagic events.

Topics: Adult; Aged; Aged, 80 and over; Area Under Curve; Blood Cell Count; Comorbidity; Databases, Factual; Female; Follow-Up Studies; Hemorrhage; Hemorrhagic Disorders; Humans; Hydroxyurea; Leukocyte Count; Male; Middle Aged; Phlebotomy; Platelet Aggregation Inhibitors; Polycythemia Vera; Prognosis; Quinazolines; Retrospective Studies; Risk Factors; Thrombocythemia, Essential; Thrombophilia; Thrombosis; Young Adult