Could Weakness and Fatigue Be the First Signs of Cancer?

Everyone may feel weakness or fatigue at certain times in life or daily. This may result from increased workloads or stress. It would be incorrect to call every instance of weakness and fatigue a sign of cancer. However, if physical fatigue and exhaustion occur more frequently, their causes should be investigated. Cancer may be one cause.

Note: Although often used to mean the same thing, weakness and fatigue have different meanings.

• Weakness is a lack of physical or muscular strength, making it feel as though extra effort is needed to move your arms, legs or other muscles. In English and medical terminology, it is called weakness .
• Fatigue or feeling tired means needing rest because of a lack of energy or strength. It may result from overwork, poor sleep, anxiety, boredom or insufficient exercise. It may also be caused by a disease such as heart failure or a medical treatment such as chemotherapy. Anxiety or depression may also cause tiredness. In English and medical terminology, this is called fatigue .

When and How Often Can Fatigue Be a Sign of Cancer?

Patients with cancer commonly experience fatigue and weakness during treatment. However, this often results not from cancer but from side effects of medicines given during treatment. In most people with cancer, weakness therefore begins after diagnosis.

Cancer types in which weakness and fatigue may be initial symptoms include leukemia (blood cancer) and lymphoma (lymph cancer).

Defining Cancer Fatigue

Defining fatigue accurately is important because it may be an initial cancer symptom. Cancer fatigue is not ordinary tiredness, nor is it like tiredness from sleeplessness or a busy period. People experiencing fatigue as a cancer symptom describe it as whole-body fatigue . They may feel too tired to take part in normal activities or perform routine tasks.

During cancer treatment, you may experience:

• An overwhelming sense of fatigue
• Fatigue persisting despite rest
• Tiring even with simple movements such as walking to the mailbox
• Difficulty concentrating
• Feeling more emotional than usual
• Less desire to participate in favorite activities.

How Does Cancer Cause Fatigue?

Fatigue in a person with cancer has various causes;

• Leukemia and lymphoma may allow cancer cells in the bone marrow to interfere with normal blood cell production. This may cause anemia, and anemia may cause weakness and fatigue.
• Colon or stomach cancer and similar cancers may cause anemia through blood loss, resulting in fatigue.
• Tumor metabolic processes may also cause fatigue.
• Another cause is disruption of hormonal function by some cancer types.
• Some cancers secrete substances called cytokines, which may cause fatigue.

What Can You Do About Cancer Fatigue?

Besides telling your doctor about extreme fatigue and weakness, there are ways you can help relieve it:

• Exercise: Although exercising may seem very difficult when you feel exhausted, it can help increase your energy if you are able. Exercise may help you rest better in the evening and sleep more soundly.
  - Related topic: Exercise for physical and mental weakness in people with cancer
• Proper nutrition: Healthy, balanced eating is very important during this period. An appropriate diet can support weight control and adequate, balanced nutrition. Eat healthy foods that maintain energy levels, including adequate vitamins, minerals, protein and fresh fruits and vegetables. A dietitian can help.
• Being happy: Mental health is among the factors affecting fatigue and physical energy. Cancer treatment can be emotionally challenging, and if you think you have depression or anxiety, we strongly recommend seeking treatment support.
• Being realistic: Be realistic during this process and reconsider some expectations and abilities from the outset. Having less energy than before illness is quite normal. Identify when you have the most energy during the day and arrange outside activities accordingly. You may naturally be unable to do everything alone; do not hesitate to ask for help.
• A daytime nap: Short daytime naps can help even cancer-related fatigue. Keep them to no more than 1 hour (longer naps may cause grogginess and make you feel more tired). Brief naps during the day can greatly help restore energy.

It is possible to say that low-energy symptoms such as weakness and fatigue in most people with cancer improve with medicines, and that patients can also substantially recover energy through their own efforts using the methods described.

- Related topic: Weakness and Fatigue in Cancer: What Causes Them, and How Are They Treated? (detailed)