Polycythemia Vera (PV) is a slow-growing cancer of the blood. The cancer is characterized by an overproduction of blood cells within the bone marrow. Too many blood cells causes the blood to thicken. Thicker blood flows more slowly and can cause blood clots, which can lead to a heart attack or stroke.
Though without proper treatment PV can be life-threatening, some patients have it for many years before being diagnosed. In many cases, the condition is discovered during unrelated blood tests.
Persons with PV have an increased risk of developing more serious blood cancers over time, such as myelofibrosis. That said, PV is not a common cancer, occurring in only 2 people per 100,000.
When PV does occur, it happens more often in men than it does women, and most patients are over the age of 60.
While many people with PV do not have any noticeable symptoms, others may have itchiness, headache, dizziness, weakness, or fatigue.
PV is caused by defective JAK2 or TET2 genes. Under normal conditions, these genes regulate the production of blood cells. In PV patients, red blood cells and sometimes white blood cells and platelets are overproduced.
Testing for the condition typically begins with a blood test. Providers will check for an abnormally high number of blood cells. They will also check for an elevated level of erythropoietin, a hormone that stimulates the production of new red blood cells.
Doctors may also call for a bone marrow aspiration or biopsy to review the solid and liquid components of the marrow.
Treatment for PV includes bloodletting to reduce the number of cells circulating in the blood. Many patients feel better immediately following this procedure, referred to as phlebotomy. Other treatments may include taking low-dose age aspirin, medications to suppress the body’s production of blood cells, cancer medications, or therapies to reduce bothersome itching often associated with PV.