Cancer-Related Fatigue (CRF)

Understanding Cancer-Related Fatigue

Cancer-related fatigue (CRF) is a distressing, persistent sense of physical, emotional, and/or cognitive tiredness related to cancer or cancer treatment that is not proportional to recent activity and interferes with usual functioning.

How CRF Differs from Normal Fatigue

• Severity: More intense and overwhelming
• Rest doesn't help: Not relieved by sleep or rest
• Sudden onset: Can come on suddenly
• Whole body: Affects entire body, not just muscles
• Concentration: Includes mental fatigue ("chemo brain")
• Duration: Lasts longer than expected

Types of Fatigue

• Physical: Weakness, heavy limbs, slowed reflexes
• Mental: Difficulty concentrating, memory problems
• Emotional: Lack of motivation, mood changes

Causes and Contributing Factors

Cancer-Related Causes

• Tumor burden and cancer progression
• Release of cytokines by cancer cells
• Increased metabolic demands
• Organ dysfunction (liver, kidney, lung)

Treatment-Related Causes

• Chemotherapy: Direct toxic effects, anemia
• Radiation: Energy depletion, tissue damage
• Surgery: Recovery stress, deconditioning
• Immunotherapy: Immune activation, thyroid dysfunction
• Targeted therapy: Various mechanisms
• Hormonal therapy: Hormone level changes

Other Contributing Factors

• Anemia: Low red blood cell count
• Infection: Body fighting infection
• Dehydration: Inadequate fluid intake
• Electrolyte imbalances: Sodium, potassium abnormalities
• Nutritional deficiencies: Poor appetite, malabsorption
• Pain: Chronic pain is exhausting
• Medications: Pain meds, anti-nausea drugs
• Sleep disturbances: Insomnia, sleep apnea
• Depression/anxiety: Mental health impacts
• Deconditioning: Reduced physical activity

Assessment and Diagnosis

Medical Evaluation Should Include

• Complete blood count (check for anemia)
• Thyroid function tests
• Electrolyte panel
• Liver and kidney function
• Vitamin B12 and D levels
• Review of all medications
• Assessment for depression/anxiety
• Sleep disorder evaluation

Questions Your Doctor May Ask

• When did fatigue start?
• How severe is it (0-10 scale)?
• What makes it better or worse?
• How does it affect daily activities?
• Are you sleeping well?
• Any other symptoms?

Management Strategies

Evidence-Based Interventions

1. Exercise: Most effective intervention (see exercise section)
2. Energy conservation: Balance activity and rest
3. Sleep hygiene: Improve sleep quality
4. Stress management: Relaxation techniques
5. Nutritional support: Adequate calories and protein
6. Treat underlying causes: Anemia, thyroid, etc.
7. Psychosocial interventions: Counseling, support groups

Complementary Approaches

• Acupuncture: May help some patients
• Massage therapy: Can reduce fatigue
• Yoga: Gentle movement and relaxation
• Mindfulness meditation: Stress reduction
• Tai chi/Qigong: Gentle exercise

Exercise and Activity

Recommended Activities

Exercise Precautions

• Check with doctor before starting
• Avoid if platelets <50,000
• Avoid if hemoglobin <10 g/dL
• Stop if dizzy or short of breath
• Stay hydrated
• Avoid during fever

Energy Conservation Techniques

Daily Living Strategies

Work and Social Activities

• Discuss flexible schedule with employer
• Take regular breaks
• Modify work environment (ergonomics)
• Limit social commitments
• Choose less demanding activities
• Be honest about limitations

Nutrition and Hydration

Nutritional Strategies

• Eat regularly: Small, frequent meals
• Protein: Include at each meal (helps maintain muscle)
• Complex carbohydrates: Sustained energy
• Iron-rich foods: If anemic (with vitamin C for absorption)
• B vitamins: Energy metabolism
• Avoid sugar spikes: Limit simple sugars

Hydration Tips

• Aim for 8-10 glasses of fluid daily
• Keep water bottle nearby
• Monitor urine color (pale yellow is goal)
• Include hydrating foods (fruits, soups)
• Limit caffeine and alcohol

Energy-Boosting Snacks

• Greek yogurt with berries
• Apple slices with nut butter
• Trail mix
• Cheese and whole grain crackers
• Hummus with vegetables
• Protein smoothies

Sleep Management

Sleep Hygiene Tips

• Schedule: Same bedtime/wake time daily
• Environment: Dark, quiet, cool (65-68°F)
• Limit naps: 20-30 minutes before 3 PM
• Avoid screens: 1 hour before bed
• Relaxation: Calming routine before bed
• Comfortable bed: Good mattress and pillows

Common Sleep Disruptors

• Pain - manage before bedtime
• Hot flashes - cool room, moisture-wicking sheets
• Anxiety - relaxation techniques
• Medications - discuss timing with doctor
• Frequent urination - limit evening fluids

When to Talk to Doctor About Sleep

• Insomnia lasting >2 weeks
• Loud snoring or gasping (sleep apnea)
• Restless legs
• Daytime sleepiness despite adequate sleep
• Need for sleep medications

Medications for Fatigue

Stimulants (Prescribed Selectively)

• Methylphenidate (Ritalin): May help severe fatigue
• Modafinil (Provigil): Promotes wakefulness
• Dexamphetamine: Reserved for severe cases

Other Medications

• Corticosteroids: Short-term energy boost
• Antidepressants: If depression present
• Erythropoietin: For chemotherapy-induced anemia
• Iron supplements: If iron deficient
• Thyroid hormone: If hypothyroid

When to Seek Help

Schedule Appointment If:

• Fatigue worsening despite interventions
• Interfering significantly with daily life
• New symptoms developing
• Depression or anxiety symptoms
• Need help with management strategies

Tracking Your Fatigue

Patterns to Notice

• Best and worst times of day
• Activities that increase/decrease fatigue
• Relationship to treatment schedule
• Impact of sleep quality
• Effect of exercise or rest

Share with Healthcare Team

Bring your fatigue log to appointments to help your team:

• Understand your fatigue pattern
• Identify contributing factors
• Adjust treatment plan
• Monitor intervention effectiveness

Resources and Support

Support Options

• Support groups: Share experiences with others
• Individual counseling: Coping strategies
• Occupational therapy: Energy conservation training
• Physical therapy: Exercise programs
• Nutritionist: Dietary planning
• Social worker: Resources and assistance

Online Resources

• Cancer.Net fatigue information
• National Cancer Institute resources
• CancerCare online support groups
• Fatigue Coalition materials

Mobile Apps

• Symptom tracking apps
• Meditation/relaxation apps
• Sleep tracking apps
• Exercise programs

Tips for Caregivers

• Understand fatigue is real and debilitating
• Help with energy conservation planning
• Assist with daily tasks
• Encourage gentle activity
• Provide emotional support
• Attend medical appointments
• Take care of your own energy too

Related Topics

References

1. NCCN Clinical Practice Guidelines. Cancer-Related Fatigue. Version 1.2026.
2. Bower JE. Cancer-related fatigue: Mechanisms, risk factors, and treatments. Nat Rev Clin Oncol. 2025.
3. American Cancer Society. Managing Cancer-Related Fatigue. 2026.
4. Mustian KM, et al. Comparison of pharmaceutical, psychological, and exercise treatments for cancer-related fatigue. JAMA Oncol. 2025.
5. Oncology Nursing Society. Putting Evidence Into Practice: Fatigue. 2025.