People with myeloproliferative neoplasms (MPNs) usually don’t notice symptoms early in the disease. Once symptoms start to develop, it’s easy to mistake them for symptoms of other conditions or assume they’re a part of your everyday life. Recognizing the early symptoms of MPNs that can often go unnoticed can help your doctor pinpoint the cause, getting you the help you need sooner.

MPNs are a group of blood cancers that begin when the bone marrow (the spongy center of bones) makes too many blood cells. This includes red blood cells (RBCs), white blood cells (WBCs), and platelets. MPNs may also be mistaken for other types of blood cancer, including leukemia. To confirm an MPN diagnosis, your doctor will look for abnormalities in your blood cell counts that point to one disorder type over another.

Signs and Symptoms of MPNs You May Not Notice

MPNs tend to develop slowly over time, so symptoms don’t always show up right away. These types of cancer tend not to show early signs, either. Instead, signs and symptoms only begin once the disease has progressed and excess blood cells have built up within the body.

The three main types of MPNs also affect different blood cell types, so the early symptoms can vary between them. Essential thrombocythemia (ET) develops when the bone marrow makes too many platelets, which normally help blood clot. Polycythemia vera (PV) develops when the bone marrow makes excess RBCs. Primary myelofibrosis (MF) is caused by a buildup of abnormal mature blood cells within the bone marrow, which can lead to scarring (fibrosis) within the bone tissue.

Common symptoms of MPNs that may be mistaken for other conditions include:

• Weakness and fatigue
• Pain or discomfort throughout the body
• Unexplained weight loss
• Abnormal clotting and bleeding
• Night sweats

Discuss any symptoms you’re experiencing with your doctor, so they can correctly diagnose the condition and develop your treatment plan.

Weakness and Fatigue

Fatigue is an extremely common symptom of cancer and MPNs, which affects up to 95 percent of people with MPNs. Fatigue in people with MPNs is likely due to a combination of factors, including the disease itself, the medication used to treat it, and the stress and anxiety that often come with having a chronic illness.

Because fatigue is such a common symptom of many conditions or just a busy life, it can be easy to overlook. One specific factor that can worsen fatigue in people with MPNs is anemia.

Anemia

Anemia can eventually develop in people with MPNs. It occurs when there are not enough RBCs to carry oxygen throughout the body, which can leave you feeling weak or fatigued. Late in the disease, MF can often cause a loss of production of RBCs caused by damage to the bone marrow. MPNs can also lead to problems with excessive bleeding, which can also worsen anemia.

Although blood cancers cause anemia, there are other more common causes of anemia that may lead to an MPN going unnoticed or misdiagnosed. The most common type of anemia is caused by a shortage of iron in the body. Iron is necessary for making hemoglobin, the protein that carries oxygen on RBCs. If iron levels are low, the bone marrow can’t make enough hemoglobin, which means less oxygen is reaching the body’s tissues. Low vitamin B12 and B9 (folate) levels can also interfere with the production of healthy RBCs, leading to anemia.

Pain and Discomfort

Pain is another commonly reported side effect of MPNs, and it can occur early or late in the disease. The most common types are joint and bone pain, along with abdominal pain.

Joint pain and swelling from MPNs may be misdiagnosed as arthritis or gout, as these are fairly common conditions. To complicate matters, gout can also develop in people with PV or MF. In PV and MF, the body may produce too much uric acid, which then builds up as crystals in the joints, causing gout.

Bone pain is also commonly reported in people with MPNs, especially in those with MF and PV. Researchers believe that bone pain is caused by inflammation in the tissue that surrounds the bones, along with the overproduction of new cells in the bone marrow. MPNs are mainly diagnosed in people who are 60 to 70 years old. Doctors may also mistake bone pain from an MPN for aging-related pain due to another condition, like osteoarthritis (when the cartilage that cushions the ends of bones in your joints gradually breaks down).

Weight Loss

Weight loss is one of the less common symptoms of MPNs, reported in around 34 percent of cases. According to the MPN Research Foundation, it occurs more often in those with MF and PV. People with cancer often lose weight unintentionally, especially if they have a loss of appetite or abdominal pain. For those with an MPN, loss of appetite or feelings of fullness may be caused by an enlarged spleen (known as splenomegaly) pressing against the stomach and other organs. Splenomegaly occurs when the spleen makes more blood cells because the bone marrow is damaged. It also occurs because the spleen is filtering out large numbers of damaged cells from the blood.

Along with a loss of appetite and abdominal pain, unexpected weight loss may be caused by other more common conditions, such as diabetes, thyroid diseases, or stomach problems. When talking to your doctor about your symptoms, be sure to mention if you have upper abdominal pain on the left side or if you get full quickly. These symptoms are specific to splenomegaly and can help direct your doctor to find the correct diagnosis.

Abnormal Clotting or Bleeding

MPNs cause the production of too many blood cells, which can interfere with the body’s ability to form blood clots. This may lead to too much blood clotting or excessive bleeding, depending on the MPN subtype you have. These can occur in people with ET, MF, and PV and include symptoms such as:

• Nosebleeds
• Easy bruising
• Bleeding in the abdomen or gastrointestinal tract
• Heavy menstrual periods
• Blood in the urine

Easy bleeding and bruising are more common in general in women and older adults. As you age, you lose the protective layer of fat underneath the skin, making it easier to break blood vessels and develop bruises. Taking certain medications can also increase your risk of easy bleeding, including over-the-counter pain relievers and blood thinners.

Night Sweats

Reported in around 56 percent of cases, night sweats are another uncomfortable MPN symptom. Night sweats are caused by the release of cytokines, which help control inflammation in the body. As cytokine levels increase, you begin to sweat. Night sweats are more common in people with PV and MF, and are not often seen in those with ET.

Some people may not connect night sweats with MPNs, and instead, think that their room is too hot or the sweating is a side effect of menopause. Other conditions that cause night sweats include:

• Anxiety
• Sleep apnea
• Thyroid problems
• Autoimmune diseases

Diabetes drugs, hormone therapy, and antidepressants can also cause night sweats.

Find Your Team

Find others to connect with at myMPNteam, the online social network for people and their loved ones living with myeloproliferative neoplasms. On myMPNteam, more than 2,600 members come together to ask questions, give advice, and share their stories with others who understand life with MPNs.

Have you experienced MPN symptoms? Share your experience in the comments below, or start a conversation by posting on your Activities page.