A retrospective study of 103 patients with essential thrombocythemia was carried out to evaluate the incidence of thrombohemorrhagic complications and establish whether there were any correlations between these events and clinical or laboratory data. At onset or during the course of the disease, 26 patients (25.2%) presented thrombotic and 12 (11.6%) hemorrhagic complications: among the latter, six patients had gastrointestinal bleeding during antiaggregant therapy. No significant correlations were observed between thrombohemorrhagic complications and platelet count, age, sex, platelet function, bleeding time, or therapeutic regimen. However, there was a statistically significant correlation between a positive patient history for thrombotic events and an increase in thromboses. In agreement with other authors, it is believed that the best approach in asymptomatic patients is strict surveillance without treatment. Chemotherapy and/or treatment with antiaggregant agents should be reserved for symptomatic patients or patients with a positive history for thrombotic events. Cancer 672926-2930,1991.
SSENTIAL THROMBOCYTHEMIA (ET) is a chronic E myeloproliferative disorder of unknown origin, characterized by persistent peripheral thrombocytosis and abnormal proliferation of megakaryocytes in bone marrow. ' Like other myeloproliferative syndromes, ET is a rare clonal disorder involving multipotent hemopoietic stem cells.* Its main clinical manifestations are hemorrhages, thromboses, and functional symptoms (paresthesia, dizziness, headache, hazy vision, scotoma). Early publications on ET more frequently referred to the occurrence of hemorrhages, but the more recent literature describes an increasing number of thromboembolic event^.^-^ However, there is still controversy over the relative incidence of hemorrhages and thromboses.
This retrospective study of 103 patients with ET evaluates the incidence of thrombohemorrhagic complications and identifies possible correlations between these events and clinical/laboratory data. The therapeutic implications of the study findings are also discussed.