Are MPNs vascular diseases?

A high risk of arterial and venous thrombosis is the hallmark of chronic myeloproliferative neoplasms (MPNs), particularly polycythemia vera (PV) and essential thrombocythemia (ET). Clinical aspects, pathogenesis and management of thrombosis in MPN resemble those of other paradigmatic vascular diseases. The occurrence of venous thrombosis in atypical sites, such as the splanchnic district, and the involvement of plasmatic prothrombotic factors, including an acquired resistance to activated protein C, both link MPN to inherited thrombophilia. Anticoagulants are the drugs of choice for these complications. The pathogenic role of leukocytes and inflammation, and the high mortality rate from arterial occlusions are common features of MPN and atherosclerosis. The efficacy and safety of aspirin in reducing deaths and major thrombosis in PV have been demonstrated in a randomized clinical trial. Finally, the Virchow's triad of impaired blood cells, endothelium and blood flow is shared both by MPN and thrombosis in solid cancer. Phlebotomy and myelosuppressive agents are the current therapeutic options for correcting these abnormalities and reducing thrombosis in this special vascular disease represented by MPN.