Cancer Fatigue

Cancer fatigue is one of the most common side effects experienced by people with cancer, affecting more than 80% of those receiving treatment. Unlike ordinary tiredness, this profound exhaustion doesn’t go away with rest or sleep and can impact every aspect of daily life.

Table of contents

• What is cancer fatigue?
• How cancer fatigue feels
• What causes cancer fatigue
• Impact on daily life
• Managing cancer fatigue

cancer-related fatigue, cancer treatment-related fatigue

What is cancer fatigue?

Cancer fatigue is a condition caused by cancer or cancer treatment in which you feel exhausted or extremely tired. Some people with cancer have extreme fatigue most of the time and are unable to carry out day-to-day tasks. Others feel only very tired^[2].

Cancer fatigue is very different from the tiredness that healthy people feel. When a healthy person is tired, fatigue is usually caused by activity and goes away after resting or sleeping. However, cancer fatigue is not completely relieved by sleep or rest and may happen after no or minimal activity^[2].

Cancer-related fatigue affects between 80% to 100% of people with cancer. It is one of the most common side effects of cancer treatment, with more than 80% of people experiencing fatigue while receiving chemotherapy (cancer treatment using drugs) or radiation therapy (cancer treatment using high-energy rays)^[2][3].

How cancer fatigue feels

People with cancer often describe the fatigue as making them feel tired, weak or exhausted. The fatigue can be physical or emotional. It often isn’t helped by usual measures, such as resting or getting a good night of sleep^[1].

Whether and how you experience fatigue depends on factors such as the type of cancer, stage of cancer, cancer treatment you are receiving, and your overall physical and emotional health, nutrition, and sleep patterns^[2].

Symptoms of cancer fatigue include^[2]:

• having no energy; feeling extremely tired, drained, or lethargic
• having difficulty moving; feeling heavy or slow
• having difficulty thinking, remembering, or paying attention
• having a sense of physical, emotional, and mental exhaustion
• not feeling rested, even after sleeping

People who experience cancer fatigue describe it as paralyzing tiredness that doesn’t go away no matter how much rest or sleep they get. With cancer fatigue, you may feel exhausted for no clear reason^[3].

What causes cancer fatigue

Cancer fatigue has many possible causes. The type of cancer you have, the kinds of treatments you’re having, and your overall health can all play a part in cancer fatigue^[1]. The exact causes of cancer fatigue aren’t always clear.

Fatigue from cancer itself

Sometimes the source of fatigue in someone with cancer is the cancer itself. Cancer cells use calories and nutrients that your body needs for energy, making you feel fatigued. Cancer can also cause your body to release cytokines, naturally produced substances that help your body to fight infections and cancer but that can cause fatigue when released at high levels^[2].

Cachexia, a wasting syndrome that causes muscle and weight loss in some people with cancer, can also lead to fatigue. Certain types of cancer are more likely to cause fatigue than others^[2].

Blood cancers such as leukemia, lymphoma, and multiple myeloma affect the bone marrow, making it difficult for your body to produce healthy blood cells. If your red blood cell count is low, your body’s tissues can’t get enough oxygen, resulting in fatigue. Breast cancer and prostate cancer can affect your hormone levels, which can lead to fatigue. Gastrointestinal system cancers such as stomach cancer and colorectal cancer can affect the way your body processes and uses food^[2].

Fatigue from cancer treatments

Many cancer treatments can reduce your energy level. When you have cancer treatment, you’re receiving medication that targets cancer but may also affect healthy cells and tissue. When this happens, it can change how cells work, cause inflammation, make you feel nauseated and dehydrated, change hormone levels, damage tissues and cells, reduce red blood cell levels (which leads to anemia), and boost cytokine production^[3].

Any chemotherapy drug may result in fatigue that may last a few days, as long as you’re receiving treatment or even after you finish treatment. Radiation therapy can cause cumulative fatigue, meaning fatigue that increases over time. Cancer fatigue from radiation therapy usually lasts from three to four weeks after treatment stops, but can continue for up to two to three months. Immunotherapy, which stimulates your immune system to fight cancer, can also cause cancer fatigue^[3].

Other contributing factors

In general, causes of cancer fatigue may include the cancer itself, cancer treatment, chronic pain, emotions such as feeling anxious, distressed, or depressed, difficulty sleeping, difficulty getting enough nutrition, certain medicines such as pain relievers, changes in your activity level, changes in the levels of hormones in your body, and stress^[1].

When you have cancer, your body’s immune system is working hard to fight the disease, so it’s constantly drawing on your energy stores. A cancer diagnosis may make you feel depressed and anxious. But fatigue and depression often go together, with depression sometimes making you feel like you’ve lost the will to do anything. Research shows that chronic, severe pain increases fatigue. Stress from dealing with the disease, worrying about your future or simply trying to keep up with your typical tasks and responsibilities can worsen fatigue^[3].

Impact on daily life

Fatigue can affect not only your daily activities but also your family, work, and social life^[2]. Cancer fatigue may last a few weeks (acute) or for months or years (chronic). Chronic cancer fatigue can harm your quality of life^[3].

Fatigue can be very frustrating. Everyday life can be difficult and you might not have the energy to cook, clean, bathe or go shopping. You might not even feel up to a chat. Things that you used to find easy to do can feel like hard work^[4].

Fatigue can affect the way you feel about yourself and your relationships with other people. You can feel very down and not want to go out or be with people which can be hard for them to understand. You might have to stop working or cut down your hours. Some people feel like fatigue is a constant reminder of their cancer and this can be hard to accept^[4].

When fatigue occurs

Fatigue can begin at any time—before, during, or after cancer treatment. Sometimes it’s an early symptom of cancer, or it can be brought on by the stress of a cancer diagnosis. Fatigue may start even before your cancer diagnosis. For some people, the fatigue starts after a diagnosis. Others aren’t hit with cancer fatigue until treatment starts^[1][2].

Fatigue may worsen gradually as you go through treatment, or it may come on suddenly. Fatigue usually decreases after cancer treatment ends, but some people may still feel fatigue for months or years. Some people have cancer fatigue that lasts long after treatment ends. Up to 30% of cancer survivors report a loss of energy for years after they complete treatment^[2][9].

Managing cancer fatigue

Although cancer fatigue can feel overwhelming, your health care team can help you find ways to manage, treat, and cope with fatigue that are tailored to you^[2]. It’s important to tell your doctor or nurse how you’re coping day to day and if you are struggling^[4].

Exercise and physical activity

Research shows that daily physical activity helps people with cancer. It can make you feel better, give you more energy, improve your appetite, and help with your mood. While it may seem counterintuitive, gentle physical activity can actually help combat fatigue^[8].

To start with, you could go for a short walk each day. Walking is a good way to be more active and help maintain your weight. When you’re ready, try to increase the distance you walk. It’s important to work at your level. When you start, build up safely and gradually. It’s also important that you do something you enjoy^[8].

If you’re having treatment or have advanced cancer you should try to keep as active as you can. Talk to your doctor, nurse, or physiotherapist about what you can do so you can find a realistic goal and don’t overdo things. Remember to not overdo it, work at your level of comfort and pace, build up gradually, and drink plenty of water whenever you exercise to prevent dehydration^[8].

Other approaches

Clinical practice guidelines conclude that doctors should recommend exercise, cognitive behavioral therapy, mindfulness-based programs, Tai chi, qigong, and American ginseng to reduce fatigue severity during cancer treatment. After completion of cancer treatment, the guidelines also suggest that exercise, cognitive behavioral therapy, and mindfulness-based programs help with cancer-related fatigue. Other post-treatment aids, according to evidence, include yoga, acupressure (a type of massage therapy), and moxibustion, a traditional Chinese medicine conducted by practitioners that involves burning mugwort leaves on or near the body’s acupuncture points^[11].

Treating underlying causes

Your doctor will want to check for other medical conditions that may be causing your fatigue. There are several possible causes, these might include sleep apnoea (when your breathing stops and starts during your sleep), depression, long term lung problems, heart failure, liver failure, or diabetes. Treating the cause and the symptoms of fatigue can improve how you feel^[8].

Some people with cancer will have anemia at some point during their illness. Anemia is when you have a low number of red blood cells in your blood. One symptom of anemia is feeling tired. To increase the level of red blood cells it might be helpful to have a blood transfusion, but not everyone needs this. Another treatment for anemia is a drug called erythropoietin or EPO. EPO is a hormone made by your kidneys that encourages the body to make more red blood cells^[8].

Sleep and rest

Sleepless nights can make you feel tired, irritable, and a bit dazed. It might help to change a few things about when and where you sleep if you often have trouble sleeping at night. Sometimes getting too much sleep is not helpful either. To help you sleep as well as possible try to go to bed and get up at the same time each day, make sure the room you sleep in is comfortable, calm, quiet and not too hot or too cold, and spend time relaxing before bed^[8].

Energy management

One of the most effective ways to cope with cancer-related fatigue is by practicing energy conservation. This involves pacing yourself throughout the day and focusing on tasks that matter most. Using a diary or planner to track your energy levels can help identify patterns, allowing you to schedule important activities during times when you feel most energized^[18].

Lifestyle tips that may help alleviate fatigue include drinking plenty of fluids, making an effort to eat at least three meals a day, and engaging in exercise to increase energy levels^[18].