Cancer-Related Fatigue
Overview
15 to 90% of patients have cancer-related fatigue (CRF)
1 in 3 people have persistent fatigue for years
Affects QoL
Fatigue is often the most distressing symptom of cancer treatment and is consistently under-reported
Definition
Distressing, subjective sense of physical, emotional and/or cognitive tiredness
CRF differs from normal fatigue which is usually temporary and relieved by rest
Factors
Cancer therapy including CTx
Tumour growth
Unrelieved pain
Anaemia
Metabolic disturbances such as poor nutrition
Medication side effects
Deconditioning
Depression mood, emotional distress, and sleep disturbance
Pathogenesis
Direct CNS toxicity from treatment
Anaemia and myelosuppression
Loss of muscle mass and abnormalities in using ATP
Neurophysiologic skeletal muscle changes
Chronic stress response + HPA
Immune activation and proinflammatory cytokines
Disrupted sleep
Hormonal changes
Criteria
Assessment
Consider scoring tools to assess fatigue
History
Fatigue onset, duration, pattern of fatigue
Associated factors
Alleviating factors
Effect on physical and cognitive functioning and on patient’s ADL
Comprehensive review of systems is warranted to ascertain organ systems affected
Directed physical exam
Directed investigations
Smoking, alcohol, illicit drug use, work history
Activitiy level and exercise tolerance
Diagnostic Workup
Electrolytes (sodium, potassium, chloride, bicarbonate)
Chemistry panel (creatinine, blood urea nitrogen, glucose, magnesium, calcium, phosphorus, total bilirubin, serum transaminases, alkaline phosphatase, lactic dehydrogenase, albumin, total protein)
Thyroid-stimulating hormone (TSH)
Complete blood count (CBC) with differential and platelet count
Serum testosterone, in males if clinical history suggestive of hypogonadism
Possible contributory factors
Medications
Often overlooked cause of fatigue
Activity level
Deconditioning
Formal exercise programs
Baselines ADLs
Nutritional assessment
Weight changes, caloric intake, fluid and electrolyte balances
Treatment
Control of contributory factors
If any factors known to be associated with fatigue are identified then treat them accordingly
Anaemia, Thyroid, Sleep Disorders, Opioid sedation etc
Optimise physical symptoms such as pain, nausea, dyspnoea
Anaemia
Symptomatic anaemic needs an accurate diagnosis to look for causes
Blood loss, haemolysis, iron folic acid, Vitamin B12
Sleep Disturbance
For those with insomnia or other sleep disturbance, implement measures to improve
Exercise
150 minutes of moderate aerobic activity per week (fast walk, cycle, swim)
2 to 3 strength training sessions weekly (weight lifting)
Cancer patients often advised to downregulate activity to avoid fatigue, this leads to muscular all wasting and deconditioning
Most studies looking at exercise during and after cancer treatment show benefits in fatigue
Also improvements in cardiorespiratory fitness, strength, fatigue, moderate reduction in sleep disturbance
Mind and body practices
Cognitive behavioural intervention
Meditation and mindfulness-based approaches
Good evidence mindfulness-based stress reduction may relieve fatigue in cancer survivors
Yoga
Small but significant effect
Acupuncture
Small amount evidence
Tai chi
Small amount evidence
Psychostimulants
For severe fatigue can consider
Modafanil 100 to 200mg mane and midi
Methylphenidate 5mg mane and midi
Testosterone
Hypogonadal men
Antidepressants
No improvement on fatigue
Glucocorticoids
Terminal phase with a high degree of burden
Ginseng
Therapeutic trial reasonable
Small studies show evidence
Vitamins
No evidence