Fatigue in cancer patients: tumor-induced fatigue

Fatigue describes a persistent, subjective feeling of physical, emotional and/or cognitive exhaustion that is out of proportion to current activity. If we now add the aspect of “tumor-induced”, i.e. tumor-related, this is such a feeling of exhaustion associated with cancer or even its treatment.

Fatigue describes a persistent, subjective feeling of physical, emotional and/or cognitive exhaustion that is not related to current activity. If we now add the aspect of “tumor-induced”, i.e. tumor-related, we are dealing with such a feeling of exhaustion in connection with cancer or its treatment.

Up to 90% of cancer patients suffer from fatigue as a result of the disease. Fatigue is the most common symptom of this disease, or the most common side effect of cancer treatment. Fatigue can subside over time, but in 20-50% of patients fatigue becomes chronic. According to the German Cancer Society, tumor-related fatigue occurs more frequently in leukemia, lymphoma, metastatic breast cancer and in connection with chemotherapy and radiotherapy. unfortunately, the majority of patients suffering from fatigue are not treated adequately. Why? Many patients consider the feeling of fatigue to be a “normal” side effect of therapy and doctors often lack the knowledge and skills to treat this condition.‍

‍

‍

What are symptoms tumor-related fatigue?

Tumor-related fatigue is multifaceted and can have a long-lasting effect on the body, emotions and cognitive functions. Patients often suffer from

• reduced physical performance
• an increased need for sleep that cannot be satisfied
• persistent tiredness and exhaustion, even during the day
• Feeling of heavy limbs
• Lack of motivation and drive
• difficulties in coping with everyday tasks
• declining interest, sadness, anxiety, increased distractibility, difficulty finding words, concentration problems

‍

The American Fatigue Coalition defines the disease as the occurrence of several of the above-mentioned symptoms, which cannot be alleviated or can only be alleviated to a limited extent by rest and sleep and which significantly impair everyday life, over a period of more than 2 weeks. There is currently no specific biomarker for diagnosing fatigue syndrome, so doctors use various questionnaires to record these specific symptoms.

The first symptoms, such as severe, persistent fatigue in everyday life, can actually occur before diagnosis; however, fatigue can also develop during treatment, in the event of a relapse or even years after successful treatment.

‍

Symptoms and accompanying symptoms of depression and also those of cachexia/malnutrition have many similarities with tumor-related fatigue.

In depression and fatigue, listlessness, tiredness, a feeling of weakness and depressive moods occur. Depression, on the other hand, is often accompanied by a persistent feeling of worthlessness, inappropriate feelings of guilt, hopelessness and recurring thoughts of death, which are not common in fatigue. In addition, the symptoms of depression usually improve during the course of the day, whereas fatigue is characterized by a decline in performance during the course of the day.

Cachexia can be the cause of fatigue, but should be recognized and treated as a separate illness.It is also particularly important to exclude diseases that can trigger symptoms such as tumor-related fatigue but are potentially treatable (e.g. anemia, electrolytes, organic dysfunctions, hypothyroidism, infection, hormones, vitamin deficiency).

The many overlaps make it clear that fatigue cannot be treated as a single symptom, but should be treated as a symptom cluster in the context of treatment.

‍

‍

How does tumor-related fatigue develop?

The complex causes of tumor- or cancer-relatedare not yet fully understood, but there are some hypotheses.

One hypothesis is based on the division of tumor-related fatigue into a primary and a secondary form, which differ in their causes.

• Primary causes
  In this context, primary forms refer to causes in which the tumor affects distinct body systems directly, i.e. the immune system, metabolism or other hormonal processes and thereby directly triggers exhaustion
  ‍
• Secondary causes
  In this context, secondary forms refer to causes which are originated in tumor and therapy accompanying symptoms and/or comorbidities.
  Possible concomitant diseases triggered by the tumor or the therapy can include
  ‍
  • Cachexia/malnutrition (due to reduced food intake)
  • Anemia/anaemia
  • fever
  • infections
  • depression
  • Imbalances of the electrolyte and hormone balance.

‍

These two forms have an inflammatory process in common, which current researchers suspect to be a serious cause of the origin of the disease.

Other causes such as

• genetic risk factors
• psychosocial factors (pre-therapy fatigue, depression, sleep disturbance, dysfunctional coping, loneliness)
• biobehavioral factors (physical inactivity, high BMI)

are being scientifically discussed.

Ultimately, however, it is often not possible to identify a specific psychosocial or physical cause.

‍

‍

What can be done against tumor-related fatigue?

There is currently no cure for cancer-related fatigue, but there are some measures that have proven to be effective in treating it.An early start to treatment is beneficial to prevent chronicity in the course of the disease.

The treatment concept is often based on two pillars: the non-drug and the drug pillar.In non-drug therapy, the focus is on advising patients and their environment, showing them ways of dealing with the disease (dosage of activity and rest, prioritization, support).

Meta-analyses and reviews have shown that in the area of physical activity, endurance and strength training, yoga and qigong can be particularly helpful in reducing fatigue. Cognitive behavioral therapy and relaxation techniques, such as Mindfulness Based Stress Reduction (MBSR), have also been shown to reduce fatigue. Multimodal therapy approaches and combined interventions appear to be useful here.

Drug therapy is currently not officially approved for this condition, but treatment with psychostimulants (methylphenidate, modafinil) or corticosteroids may be considered. This should always be discussed with your doctor! Other medications are being discussed, but no specific recommendation can yet be made.