An Overview of MPNs
Myeloproliferative neoplasms (MPNs) are a closely related group of progressive blood cancers in which the bone marrow typically overproduces one of the mature blood elements. Other shared features include tendencies toward blood clotting/bleeding, organ enlargement, bone marrow scarring (fibrosis) and a possibility of transformation. Although MPNs can strike anyone at any age, most patients are afflicted in the sixth decade of life or later.
Stem cell transplants may offer a cure for some myelofibrosis sufferers. But there are no known cures for most MPNs. However, patients can experience few or no symptoms for extended periods of time and many people who suffer from MPNs can enjoy longevity with proper monitoring and treatment. The identification of the JAK2 gene marker in 2005 and the CALR gene marker in 2013 have led to significant advances in the diagnosis, understanding of disease processes and treatment of MPNs.
At the MPN Research Foundation, we’re committed to funding researchers in their quest to treat and ultimately cure MPNs. But even more importantly, we’re committed to providing patients, their families and the entire MPN community with advocacy, education, and resources. Working together, we can change the prognosis and create a brighter future for people whose lives are affected by this group of diseases.
Types of MPNs
There are three blood cancer types that are categorized as “classic” MPNs: Primary Myelofibrosis (MF), Essential Thrombocythemia (ET) and Polycythemia Vera (PV):
- Primary Myelofibrosis (MF) – Most commonly seen in men and women over the age of 60, MF is a chronic blood cancer in which the bone marrow function is impacted by scarring. Patients often have associated symptoms and an enlarged spleen. MF can occur in patients with no prior history of an MPN (primary MF) or as a progression of PV or ET.
- Essential Thrombocythemia (ET) – ET is a blood malignancy that is typically characterized by an elevation of platelets in the blood. It is most prevalent in women over the age of 50 and common symptoms include blood clotting and bleeding. ET patients have a later risk of progression to MF.
- Polycythemia Vera (PV) – Characterized by an elevation of red blood cells, PV is most commonly diagnosed in men over the age of 60. PV patients often exhibit elevated white blood cell and platelet counts as well as an enlarged spleen.
What are genetic mutations?
Many MPNs are characterized by the abnormal growth of white blood cells, red blood cells, and platelets – events that can be caused by genetic mutations.
In 2005, researchers discovered an important genetic mutation associated with the MPNs. Since then researchers have discovered additional mutations including the JAK2, CALR, TET2, and MPL gene markers.
Genetic Mutations and MPN Treatments
The discovery of genetic mutations has led to significant developments in the treatment of MPNs. For example, in the wake of identifying the JAK2 mutation, researchers and physicians have been able to inhibit the JAK2 gene with a variety of compounds including a JAK inhibitor which has been approved by the FDA as well as other drugs still being tested in clinical trials.
Research is ongoing to identify and explain genetic underpinnings for the cause of the MPNs. At the MPN Research Fund, our commitment to funding leading-edge research in the area of MPN genetic mutations and gene therapies is just one of the ways that we drive improved patient outcomes and carry out our mission to work tirelessly to change the prognosis for MPN patients and their families.
How Prevalent Are MPNs?
If you or someone you love has been diagnosed with an MPN, it’s important to know that you’re not alone.
While incidence rates refer to the number of new patients diagnosed with an MPN each year, prevalence rates indicate the total number of patients living with an MPN at any given time. And with earlier diagnoses and better tracking, the numbers appear to be growing.
MPN Prevalence in the U.S.
Recently, researchers from the Mayo Clinic, Boston University School of Public Health and the pharmaceutical company Sanofi’s department of Global Evidence & Value Development, concluded a study of the prevalence of the myeloproliferative neoplasms in the U.S. Their findings were reported at the American Society of Hematology annual meeting in 2012 and in a recent scientific publication.
Age-Adjusted Prevalence (per 100,000) for MPN Subgroups of Interest for Two Large U.S. Health Plans, 2008-2010.
*unique patients only MF=Myelofibrosis; PV=Polycythemia vera; ET=Essential thrombocythemia
Based on MarketScan database estimates from 2010 (which were lower than the Impact database estimates), the projected prevalence for MPNs in the U.S. on December 31, 2010 was:
- MF – 12,812
- PV – 148,363
- ET – 134,534
The study results suggest that MPN prevalence is much higher than previously reported.
MPN Prevalence Rates and You
For patients, the key takeaway from MPN prevalence rates is that you don’t have to walk through this difficult period of your life alone. Although reported MPN prevalence rates are increasing, it could be due to better tracking of these diseases as well as earlier diagnosis. The good news is that there is a vibrant MPN community comprised of researchers, healthcare practitioners and other patients on hand to provide information and emotional support.
At the MPN Research Foundation, we’re proud to play an important role in the MPN community by supporting patients and families through research, advocacy and education. Working in tandem with the healthcare and research communities, we’re dedicated to changing your prognosis and helping you identify a path toward a brighter future.