Overview of Polycythemia Vera

Treatment & Management of Polycythemia Vera

Treatment of Polycythemia Vera

Medically reviewed by Dr. C.H. Weaver M.D. Medical Editor 9/2018

Knowledge is power. Are you facing a new diagnosis, recurrence, living with advanced disease, or supporting a loved one with a diagnosis of polycythemia vera? The Cancer Connect Polycythemia Vera Information Center has current, evidence-based information and a community of individuals sharing and supporting each other. Join the polycythemia community, and get the facts about a polycythemia vera diagnosis, treatment options, and survivorship, and stay up to date with ongoing polycythemia research that could impact your treatment decisions through our daily cancer news.[1]

Polycythemia vera is a type of blood cancer known as a myeloproliferative neoplasm. It involves the abnormal development and function of bone marrow cells that produce blood cells, and leads to the overproduction of red blood cells. White blood cells and platelets may also be overproduced. There is currently no cure for polycythemia vera, but the condition can often be managed for many years and the recent FDA approval of Jakafi® is expanding treatment options. In rare cases, polycythemia vera may progress to myelofibrosis (scarring of the bone marrow) or acute myeloid leukemia (AML).

The following is a general overview of the diagnosis and treatment of polycythemia vera. Each person with polycythemia vera is different, and the specific characteristics of your condition will determine how it is managed. The information on this Web site is intended to help educate you about treatment options and to facilitate a shared decision-making process with your treating physician.

Symptoms of Polycythemia Vera

At its early stages, polycythemia vera may not cause any symptoms. Symptoms that may develop as the condition progresses include the following:(1)

  • A feeling of pressure or fullness below the ribs on the left side.
  • Headaches.
  • Double vision or seeing dark or blind spots that come and go.
  • Itching all over the body, especially after being in warm or hot water.
  • Reddened face that looks like a blush or sunburn.
  • Weakness.
  • Dizziness.
  • Weight loss for no known reason.

Overproduction of blood cells and changes to blood flow increase the risk of serious blood clots in people with polycythemia vera. This can lead to life-threatening conditions such as heart attack, stroke, or pulmonary embolism. Treatment can reduce this risk while also helping to manage bothersome symptoms. Polycythemia vera can also cause pregnancy complications, and women who are pregnant or considering becoming pregnant may wish to talk with their doctor about how to manage their health.

Diagnosis of Polycythemia Vera

Blood tests provide the primary information necessary to diagnosis polycythemia vera. Patients may also undergo a bone marrow examination. Polycythemia vera typically involves a high concentration of red blood cells and the presence of certain gene mutations in blood cells.[2] These gene mutations, which involve the Janus kinase 2 (JAK2) gene, are identified in almost all people with polycythemia vera. JAK2 mutations are thought to contribute to the growth of polycythemia vera and some other myeloproliferative neoplasms, but the exact role of this gene continues to be studied.

Another common characteristic of polycythemia vera is lower-than-normal blood levels of a protein known as erythropoietin. People with polycythemia may also have elevated levels of platelets and/or white blood cells.

Treatment of Polycythemia Vera

Treatment of polycythemia vera can improve symptoms and reduce the risk of complications. Choice of treatment depends in part on a patient’s risk of blood clots and the discomfort of symptoms.[2],[3] Patients who are older or who have history of blood clots are considered high-risk and may require more extensive treatment than patients who are low-risk. Treatment of low-risk patients often involves phlebotomy (removal of some blood) and low-dose aspirin.

Phlebotomy The periodic removal of blood from a vein is referred to as phlebotomy (using the same technique as blood donation) and this can reduce the concentration of red blood cells.

Low-dose aspirin. Reduces the risk of blood clots.

JAK inhibitors JAK inhibitors target abnormal cell signaling that is through to contribute to the growth of cells in Polycythemia Vera and other myeloproliferative neoplasms. The JAK1 and JAK2 inhibitor Jakafi® (ruxolitinib) is the first new drug approved for the treatment of Polycythemia Vera.

A Phase III trial published in the New England Journal of Medicine has determined that Jakafi® is more effective treatment of polycythemia vera than standard therapy. Researchers compared Jakafi with standard therapies in patients who did not respond well to Hydroxyurea. Patients receiving Jakafi had significantly better disease control: 21% compared to only 1% for standard therapy, had better hematocrit control (60% versus 20%) and had a greater reduction in spleen size: 38% of Jakafi treated patients had at least a 35% reduction in spleen volume compared with only 1% on standard therapy. More patients on Jakafi experienced remission: 24% versus 9% and 49% experienced a 50% reduction in symptoms compared to only 5% with standard therapy.[4]

Hydroxyurea May be used for the treatment of high-risk patients or patients who have not responded adequately to phlebotomy and low-dose aspirin. Hydroxyurea suppresses blood cell production in the bone marrow.

Interferon Belongs to a group of biologic substances called cytokines. Interferon alpha produces its anti-cancer effects by stimulating the immune system to help fight PV and other cancers.

Symptom Management

Itching, especially after bathing, is a common and troublesome symptom of PV. Itching has been reported in up to 85% of patients.

Management of PV that Progresses to Myelofibrosis or Acute Myeloid Leukemia

In rare cases, polycythemia vera progresses to myelofibrosis (scarring of the bone marrow) or acute myeloid leukemia (AML). Among people with PV, the 10-year risk of myelofibrosis is less than 10% and the 10-year risk of AML is less than 5%.2 For information about the management of these conditions, click on one of the following:

Strategies to Improve Treatment

Clinical trials are studies that evaluate the effectiveness of new drugs or treatment strategies. Areas of active investigation aimed at improving the treatment of polycythemia vera include the following:

JAK inhibitors: Targeted drugs known as JAK inhibitors have changed the way in which polycythemia vera is treated. These drugs target abnormal cell signaling that is through to contribute to the growth of myeloproliferative neoplasms. The JAK1 and JAK2 inhibitor Jakafi® (ruxolitinib) has been approved for the treatment of myelofibrosis and polycythemia vera and researchers are working to determine when best to use Jakafi® and at what dose and schedule.

HDAC inhibitors: Other targeted drugs that are being evaluated for PV include histone deacetylase (HDAC) inhibitors. These drugs—which include givinostat, vorinistat, pabinostat, and others—interfere with enzymes that may contribute to cancer growth.

Are you facing a new diagnosis, recurrence, living with advanced disease, or supporting a loved one with a diagnosis of polycythemia vera? The Cancer Connect Polycythemia Vera Information Center has current, evidence-based information and a community of individuals sharing and supporting each other. Join the polycythemia community, and get the facts about a polycythemia vera diagnosis, treatment options, and survivorship, and stay up to date with ongoing polycythemia research that could impact your treatment decisions through our daily cancer news.

References:

[1] National Cancer Institute: PDQ® Chronic Myeloproliferative Disorders Treatment. Bethesda, MD: National Cancer Institute. Date last modified 08/07/2013. Available at: http://cancer.gov/cancertopics/pdq/treatment/myeloproliferative/Patient. Accessed 10/11/2013.

[2] Tefferi A. Polycythemia vera and essential thrombocythemia: 2013 update on diagnosis, risk-stratification, and management. American Journal of Hematology. 2013;88:508-516.

[3] Hensley B, Geyer H, Mesa R. Polycythemia vera: current pharmacotherapy and future directions. Expert Opinion in Pharmacotherapy. 2013;14:609-617.

[4] Vannucchi AM, Kiladjian JJ, Griesshammer M, et al. Ruxolitinib versus Standard Therapy for the Treatment of Polycythemia Vera. New England Journal of Medicine. 2015 Jan 29;372(5):426-35.

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