What are the effects of malnutrition and weight loss caused by altered metabolism and reduced intake in cancer?
- Decreased quality of life
- Decreased response to treatment
- Decreased survival
What are the benefits of assessing nutrition status in individuals with cancer?
- Early identification of patients at risk allows for early intervention
- Improves patient well-being, survival, immune function, and reduced morbidity
Define cachexia.
- A complex metabolic syndrome ASSOCIATED with underlying illness and characterized by loss of muscle with or without loss of fat mass
- The prominent feature is weight loss
What is the difference between cachexia and cancer?
Cachexia is a syndrome, while cancer is a disease
What is a syndrome?
Groups several conditions together, and may not be diagnosed as easily
What leads to muscle wasting in cancer patients?
- Inflammation
- Insulin resistance
- Hypogonadism
What leads to fat loss in cancer patients?
- Anorexia
- Inflammation
What are consequences of muscle wasting?
- Increased fatigue
- Increased treatment-induced toxicity
- Decreased host response to tumours
- Decreased performance status
- Decreased survival
What is sarcopenic-obesity?
Obesity with depleted muscle mass
What leads to an increased treatment-induced toxicity in cancer patients with muscle wasting?
The drugs are designed based on body surface
What is the overall prevalence of cancer cachexia?
50 to 80%
Which cancers have a more frequent prevalence of cancer cachexia?
- Upper gastro-intestinal cancer: 80%
- Upper gastric and pancreatic cancer: 83-87%
- Head-and-neck cancers render food intake more complicated
- Lung cancer: 60% (altered metabolism)
What are the two main components of the onset of cachexia?
- Metabolic change (hypercatabolism and hypoanabolism)
- Reduced food intake
Differentiate hypercatabolism and hypoanabolism.
- Hypercatabolism: increased protein degradation
- Hypoanabolism: less response to anabolic stimuli
Differentiate primary and secondary anorexia.
- Primary: driven by physiological changes due to illness itself
- Secondary: secondary to the treatment of the disease (chemotherapy, radiotherapy)
What is sarcopenia?
- Decreased muscle mass, which is typically associated with aging
- May be observed despite a lack of weight change
How does the resting energy expenditure differ between starvation and cachexia? What does that induce?
- Starvation reduces REE
- Cachexia increases REE
- The loss of weight is more rapid in cachexia than in starvation
Why is it so important to diagnose cachexia early on?
Because nutritional support provided during the refractory period (last 3 months before death) is not fruitful
Differentiate positive and negative acute phase proteins.
- Positive: plasma concentrations increase by over 25% during stress
- Negative: plasma concentrations decrease by over 25% during stress
Which protein is largely measured to indicate a positive acute phase response?
C-reactive protein
What is the acute phase response modulated by?
Cytokines
What pro-inflammatory cytokines are found in cancer?
- TNF-a
- IL-1
- IL-6
- IFN-gamma
What are the effects of cytokines on skeletal muscle wasting?
- Anorexia (reduced substrate supply)
- Direct catabolic effect on muscle
What are the effects of cytokines on the liver?
- Increase in urinary nitrogen loss (because of increased substrate demands)
- Increase in acute phase proteins
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1. Biochemistry of Life (Part I)152
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2. Introduction to Lipids and Lipoprotein Metabolism (Part I)117
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Amino Acids40
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Fatty Acids27
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2. Introduction to Lipids and Lipoprotein Metabolism (Part II)139
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2. Introduction to Lipids and Lipoprotein Metabolism (Part III)42
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3. Glucose and Carbohydrate Metabolism (Part I)124
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3. Glucose and Carbohydrate Metabolism (Part II)111
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3. Glucose and Carbohydrate Metabolism (Part III)42
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4. Amino Acid and Protein Metabolism (Part I)120
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4. Amino Acid and Protein Metabolism (Part II)138
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Undernutrition: Adaptations of Protein and Energy Metabolism59
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Red Blood Cells95
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Cancer Cachexia39
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Amino Acids (Part II)8
