Myeloproliferative neoplasms (MPNs, formerly called myeloproliferative disorders) are a group of blood diseases. In each type of MPN, there is an overproduction of one or more blood stem cells in the bone marrow. Red blood cells, neutrophils (a type of white blood cell), and platelets may not work properly. MPN symptoms are caused by these elevated levels of abnormal blood cells. Treatment options for MPNs depend on the type of disease.

Those with MPNs often have other health conditions, known as comorbidities, which are more common in this group than in the general population. These comorbidities can complicate treatment, increase the risk of complications, and add to the challenges of daily life. Managing both MPNs and additional health issues can make cancer treatment more difficult and lead to increased fatigue.

Knowing the common comorbidities of MPNs can help you recognize symptoms and talk to your doctor about treatment. Treating comorbidities may improve quality of life and lower the risk of life-threatening complications.

Some medications can cause dangerous interactions. Always make sure your health care provider is aware of every medication you are taking for every condition, whether it’s available over the counter or by prescription, including any vitamins or herbal supplements.

Infections

People with MPNs have a significantly higher risk of developing bacterial, viral, and fungal infections than people of similar ages who haven’t been diagnosed with MPNs. One study found the risk of dying from infections, especially bacterial infections, was higher in those with MPNs than in the general population.

According to another study, those with MPNs have an increased risk of infections including:

• Pneumonia
• Urinary tract infections
• Viral hepatitis

The study also revealed a much higher risk of sepsis — a dangerous reaction to infection that can lead to severe inflammation and organ damage — in those diagnosed with MPNs.

You may be more likely to develop infections because of MPNs and the treatments used to manage them. JAK2 inhibitors, a class of medications often used to treat MPNs, can contribute to a higher risk of infections. These medications reduce the activity of certain immune cells, which can lower the body’s defenses against infection.

If you’re living with MPNs, infections are more likely to become serious. Contact your doctor or a nursing advice line if you experience any of the following symptoms:

• Temperature above 99.5 F or below 96.8 F
• Skin feeling hot when touched
• Chills
• Any body pain you didn’t have before MPN treatment
• Coughing or shortness of breath
• Pain during urination
• Redness, pain, swelling, or discharge at the site of intravenous lines

Cardiovascular Conditions

Chronic (long-term) inflammation in MPNs can raise the risk of heart problems like atherosclerosis, a condition where the arteries become narrowed or blocked (commonly known as “hardening of the arteries”). This can make it harder for blood to flow normally. Younger people with MPNs have a higher risk of dying from cardiovascular problems, such as myocardial infarctions (heart attacks) or strokes, than people of similar ages who have not been diagnosed with MPNs.

Your risk of cardiovascular problems is even higher if you have these risk factors:

• Hypertension (high blood pressure)
• Diabetes
• Smoking

You and those you live with should be aware of the symptoms of severe cardiovascular events. Heart attack and pulmonary embolism (blood clot in the lung) can cause chest pain, shortness of breath, and nausea. Strokes can cause severe headaches, disorientation, impaired speech, and weakness in the arms or legs. Call emergency services immediately if you or your loved one experiences any of these symptoms.

If you’re concerned about your risk of serious cardiovascular complications, your doctor can help you find ways to reduce your risk. These may involve stopping smoking, getting regular exercise, and making changes to your diet, as well as medication. Depending on the specifics of your condition, your doctor may recommend taking aspirin, which can help lower the risk of thromboembolism (blood clots), heart attacks, and strokes in some people. However, aspirin can also raise the risk of bleeding. Always talk to your doctor before making any changes to your treatment regimen.

Blood and Bleeding Disorders

Because MPNs cause overproduction of blood cells, and the blood cells tend to be abnormal and not work properly, it’s not surprising that blood disorders are a common comorbidity.

Anemia, which means having low levels of red blood cells, can be part of the criteria for diagnosing MPNs. It may be directly caused by the MPN itself or can develop as a side effect of cancer treatment. Anemia can also be caused by nutritional deficiencies of iron or vitamin B12 or by unrelated conditions.

Symptoms of anemia include fatigue, weakness, pale skin, cold hands and feet, and shortness of breath. If you have anemia, you may also experience pain, fullness, or pressure in your abdomen from splenomegaly (an enlarged spleen). Most MPN treatment regimens address anemia. Therapies may include red blood cell transfusions, nutrition, hormonal medication like danazol, or angiogenesis inhibitors such as thalidomide and lenalidomide, which help stop the growth of new blood vessels that tumors need to grow.

People living with MPNs are more likely to experience blood clots and bleeding problems. Blood clots can block arteries and cause life-threatening events such as stroke or pulmonary embolism. Bleeding may be minor or severe.

In addition, MPNs can lead to acquired von Willebrand disease (VWD). This bleeding disorder can cause nosebleeds, excessive bleeding during dental and medical procedures, easy bruising, and heavy periods. In most cases, VWD is a genetic disorder, but it can sometimes be caused by MPNs, lupus, heart disease, or certain medications. In a study involving 116 individuals with essential thrombocythemia (ET) and 57 with polycythemia vera (PV), 55 percent of those with ET and 49 percent of those with PV developed acquired VWD. This finding suggests that nearly half of those with these MPNs are affected by this bleeding disorder.

Autoimmune Disorders

Individuals with MPNs may be more likely to develop autoimmune disorders — chronic conditions in which the immune system mistakenly attacks one’s tissues. Inflammation plays a key role in autoimmune diseases, causing pain and tissue damage. In people with MPNs, autoimmune conditions can make symptoms worse and may even speed up the growth of cancer cells, leading to faster disease progression.

These are the autoimmune conditions most commonly seen in those with MPNs, along with their major effects:

• Crohn’s disease can cause sores and damage anywhere in the gastrointestinal system, from the mouth to the anus.
• Lupus can affect any tissue but often attacks the skin, joints, kidneys, and nervous system.
• Psoriasis causes painful, itchy patches of skin with scales.
• Scleroderma causes the skin to harden and develop sores. Joints can also be affected.
• Autoimmune hemolytic anemia destroys red blood cells.
• Aplastic anemia, also known as bone marrow failure, causes the body to stop making all types of blood cells.
• Polymyalgia rheumatica results in stiffness and pain in the muscles and joints.
• Reiter’s syndrome is a type of chronic arthritis.
• Giant cell arteritis causes inflammation in the arteries. Symptoms include headaches and vision changes.

Autoimmune conditions are chronic and may have a cycle of disease flares (when symptoms are intense) and remissions (when symptoms subside). Most autoimmune conditions can be managed with medications that modify the immune system.

Secondary Cancers

People diagnosed with MPNs have a significantly increased risk of developing secondary cancer — whether another type of blood cancer or a different type of cancer altogether. Cancers that have been shown to develop more commonly in those with MPN than in other people include:

• Nonmelanoma skin cancer
• Kidney cancer
• Brain cancer
• Endocrine cancer
• Malignant melanoma
• Pancreatic cancer
• Lung cancer
• Head and neck cancer

MPNs can transform into acute blood cancers such as acute myeloid leukemia or lymphoma. ET and PV can transform into myelofibrosis.

Skin Conditions

Individuals with MPNs may develop skin changes including redness, patches, and raised areas called plaques and nodules. On darker skin tones, these changes may appear as darker or purplish spots, or areas that are raised or thickened. Sweet syndrome is another condition that can develop with MPNs. It occurs when a large number of neutrophils build up in the skin, causing painful red bumps or patches. In darker skin tones, Sweet syndrome may appear as dark brown, purplish, or grayish patches or raised areas.

Talk to Your Doctor

Living with MPNs can come with a range of added health issues, such as infections, heart problems, blood disorders, autoimmune diseases, and even other types of cancer. Knowing about these risks can help you and your doctor manage your symptoms and prevent complications. Staying informed and talking to your health care provider about any concerns can make a big difference in your overall well-being. Make sure to discuss any new symptoms or worries with your doctor to get the best care possible.

Find Your Team

On myMPNteam, the social network for people with myeloproliferative neoplasms and their loved ones, more than 4,700 members come together to ask questions, give advice, and share their stories with others who understand life with MPNs.

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