The National Comprehensive Cancer Network defines Cancer Related Fatigue (CRF) as: “a draining, unrelenting exhaustion that impedes the ability to enjoy life and carry out daily activities.”
The fatigue is not related to activity levels and significantly impacts on a person’s ability to function. It is important to note that rest or sleep does not relieve this fatigue. CRF often precedes the diagnosis, continues during treatment – sometimes as a direct result of therapy – and may persist well into remission.
Ongoing advancements with newer treatments such as dose intensified chemotherapy, multiple drug combinations (the so-called targeted therapies such as tyrosine kinase inhibitors) and more innovative radiotherapy approaches have led to a greater prevalence of CRF. Recent studies quote the incidence of CRF as ranging between 70% and 100% of patients on cancer treatment.
Patients with metastatic disease almost always complain of CRF with severe CRF occurring in over 40% of these cancer survivors. The impact on quality of life can result in a profound inability to fulfil work duties and often results in healthy looking patients seeking vocational disability.
The cause of CRF, although not exhaustively studied, probably involves the complex interaction of acute and chronic physiologic and biochemical dysregulation. These hypotheses are based on studies of chronic fatigue syndrome and exercise induced fatigue and may not reflect the entire pathophysiology behind the symptoms experienced. Whatever the mechanism I think it is fair to postulate that pro-inflammatory cytokines play a major role in the generation of CRF.
Successful symptom relief requires a multi-modal approach. The first step involves identifying all potential contributing factors that may be treated.
Mood disturbances constitute the most common cause of fatigue in cancer patients. In these patients anti-depressants are a vital part of symptom relief.
Anaemia is another contributor to tiredness that can be treated. Red cell transfusions can easily improve fatigue caused by low haemoglobin levels and, more recently, erythrocyte stimulating agents are also commonly used. In some patients this intervention only results in partial relief – bearing testimony to the complex relationship between cancer and fatigue.
Other drugs used to manage CRF include corticosteroids and other centrally acting stimulants.Corticosteroids inhibit inflammation resulting in symptom relief; centrally acting stimulants improve poor concentration and memory loss and ease tiredness.
Physical activity and psychosocial therapy can have a significant impact in tired cancer patients. Exercise has a major beneficial impact in patients with CRF. Walking, cardiovascular exercises, flexibility training and resistance training can all moderate the profound tiredness of CRF.
Psychosocial behavioural interventions also benefit many patients with CRF. Education and counselling forms an integral part of this multi-faceted approach to managing CRF. The benefit is often only moderate but, when taken in conjunction with other therapeutic modalities, a large number of cancer patients can derive significant symptom relief in this area of oncology management that is often neglected by cancer care practitioners.
My hope is that, with an integrated approach to cancer care, all of the concerns of patients fighting this dreadful illness will be comprehensively and sensitively addressed.
Speak to your cancer care practitioner if you frequently experience any of these symptoms of CRF:
Decreased energy or lack of energy
Tired and Scratchy Eyes
Tired legs and arms
Irritability or impatience
Lack of motivation
A general feeling of being unwell
NB!! If you are suffering from Cancer Related Fatigue it is a good idea to refrain from driving
Written by Dr SD Moodley