Walsh & Hoyt: Prognosis and Treatment

Without treatment, polycythemia vera is associated with a high incidence of fatal thrombotic or hemorrhagic complications and a median survival of 18 months from the time of first symptoms or signs. Treatment designed to maintain peripheral blood counts and red blood cell mass at normal levels extends median survival to about 10 years. Mortality and morbidity are influenced by treatment modality. In untreated patients and in those treated with phlebotomy alone, thrombotic complications are most common, occurring in 4160% of cases. Acute leukemia occurs in 1.5% of patients with polycythemia vera who are not treated with myelosuppression and in 1013% of patients who are treated. The development of other neoplasms, hemorrhage, and myelofibrosis are other major causes of death. Postpolycythemic myeloid metaplasia, the spent phase of the disease, develops in 1050% of patients.