Treatment of polycythemia vera.

BACKGROUND AND OBJECTIVE Current guidelines for the management of patients with polycythemia vera (PV) derive from a few clinical trials and several uncontrolled clinical studies. The purpose of this paper is to critically review the available evidence in literature for selecting the best treatment in the single patient. METHODS The authors have been working in this field contributing original papers whose data have been used for this study. In addition, the material analyzed in this article includes papers published in the journals covered by the Science Citation index and Medline. RESULTS Therapeutic strategies for patients with PV include both cytoreductive and antithrombotic drugs. Among cytoreductive treatments, phlebotomy is associated with poor compliance and an increased incidence of thrombosis in the first three-five years, whereas chemotherapy may induce an higher risk of secondary malignancies after seven-ten years of follow-up. New cytoreductive drugs virtually devoid of mutagenic risk include alpha-interferon and anagrelide, but their role in reducing thrombotic complications or mortality remains to be demonstrated. Antithrombotic drugs, such as aspirin, are frequently used in PV, despite doubts regarding safety and efficacy. CONCLUSIONS The management of patients with PV is a difficult balance between the prevention of thrombotic complications and the risk of drug side effects and toxicity. Appropriate studies are needed and an European collaboration has been set up for launching a randomized, placebo-controlled clinical trial (European Collaboration on Low-Dose Aspirin-ECLAP study) aimed at testing the efficacy of low-dose aspirin in preventing thrombosis and prolonging survival in PV patients.