When you don’t have enough healthy red blood cells, you have a condition called anemia. This means your blood has lower than normal hemoglobin (Hgb) levels. Hemoglobin is the part of the red blood cell (RBC) that carries oxygen to all the cells in your body. Anemia is a common side effect in patients with cancer.
There are many different reasons a person with cancer might have anemia. Some common causes are:
Some risk factors may make a person with cancer more likely to have anemia. These include:
Anemia often starts slowly, so you may not notice symptoms at first. As your hemoglobin level gets lower you may have one or more of these symptoms:
Anemia can range from mild to life-threatening, depending on your hemoglobin level and the symptoms you are experiencing. Some of these symptoms are more serious than others. Your doctor will explain your hemoglobin level and the severity of your anemia.
If you have any of these symptoms, tell your doctor or nurse right away. If you can’t reach your cancer care team right away, you may need to get immediate care at an emergency room.
Let your cancer care team know if you have any other medical problems such as heart or lung disease, as this may make your symptoms from anemia worse. It’s important to watch for anemia and its symptoms throughout your treatment. Tell your cancer care team if you’re having any of the symptoms described here. Be sure to mention how the symptoms affect your day-to-day life. Doing so will help you get the treatment you need when you need it.
A complete blood count (CBC) is a blood test that measures your hemoglobin level and other characteristics of your red blood cells (such as their size). This test not only shows if you have anemia, but it can also help your doctor figure out what might be causing it.
You might also need other tests to help to find what is causing it. These could include:
Your doctor or nurse can use the results of these tests, along with your medical information and a physical exam, to get an idea of what might be causing your anemia. Sometimes no cause can be found other than “anemia of chronic disease.” This type of anemia is often found in people with long-lasting problems like congestive heart failure, inflammatory diseases, or cancer.
The first thing the doctor needs to know is how severe your anemia is. Anemia can affect your quality of life and has been found to shorten survival in people with cancer. It can make you feel very tired because cells in your body can’t get enough oxygen. In some cases, this lack of oxygen may be bad enough to threaten your life. Anemia can also make your heart work harder. So if you already have a heart problem, anemia can make it worse. Anemia can also make it hard for you to breath normally, making it challenging to do your usual activities.
Severe anemia may mean you have to delay your cancer treatment or have your treatment dose reduced. It can also cause some cancer treatments to not work as well as they should.
Your cancer care team may try to figure out your risk of serious problems from the anemia based on any symptoms you are having and your hemoglobin level. If you’re not having symptoms, they will try to figure out how likely you are to have them in the near future. This will be based on a number of things, including:
If you don’t seem to be at risk for problems from anemia, your cancer care team will watch your hemoglobin level closely and ask about symptoms each time you visit the office.
Anemia in cancer patients is usually treated based on the cause. Sometimes, treatment of anemia delays cancer treatment until your red blood cells recover. There are 2 main goals in treating anemia:
The most common treatments of anemia in patients with cancer include:
Your doctor will look at your test results, symptoms, how long you've been having the symptoms, the cancer type, cancer treatment, and other factors. Talk to your cancer care team about what treatment is right for you. As with any medical problem, the expected benefits of treatment should always outweigh the possible risks.
If your iron levels are low, your doctor may supplement them with iron pills or iron given through your veins (iron infusion). Iron infusions carry a risk of allergic reaction. Your doctor will discuss with you what form of iron would be best for your situation. Your doctor may also ask you to try to eat more iron-rich foods. There are two types of iron in food: heme and non-heme.
Heme iron is found in animal products. Heme iron is more easily absorbed by the body than non-heme iron. Examples of foods that contain heme iron are:
Non-heme iron is found in plant-based foods. Examples of foods that contain high amounts of non-heme iron include:
Non-heme iron is best absorbed by the body when eaten at the same time as fruits and vegetables high in Vitamin C. Examples of foods high in vitamin C include
A blood cell transfusion is a safe and a common way to treat anemia in people with cancer. It can help the patient feel better and helps oxygen get to vital organs. While blood transfusions can help symptoms very quickly, sometimes the relief is temporary depending on the cause of anemia.
Whether a blood transfusion might be needed depends on how severe your symptoms are and your hemoglobin level. A transfusion might be done if your hemoglobin level reaches a certain number or if your symptoms get too bothersome
A blood transfusion requires careful matching of donated blood to the recipient’s blood. Blood products are tested to be sure they are safe and the same kind of blood type as the recipient. But, receiving a blood transfusion also has some risks
Another way to treat anemia in some patients is to use drugs that tell the body to make more red blood cells. ESAs work like a hormone (called erythropoietin) made by the kidneys to help the body make its own new red blood cells. If one of these drugs is recommended, your health care provider will talk to you about the risks and the benefits of the drug. These drugs can cause very serious side effects. Still, they can help patients getting chemotherapy have higher hemoglobin levels and need fewer blood transfusions. This may result in a gradual improvement of anemia-related symptoms.
ESAs are given as shots under the skin, and how long they take before they start working may be different for different patients. Talk to your doctor about the risks and benefits of the ESA you will be receiving..
Depending on the type of anemia you have, the anemia may also be treated with vitamin B12 or folic acid supplementation.
Talk to your doctor about what kind of anemia you have, the recommended treatment, and the risks and benefits of the treatment.
(The last 2 are signs of bleeding, which can be a cause of anemia.)
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
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Last Revised: February 1, 2020
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