L4 - Nutrition & Cachexia

Question 1

Why is the site of cancer important to consider when managing cancer?

Answer 1

Cancers near the head & neck will impact how patients eat/chew e.g oral cancer vs breast cancer

Question 2

How can radiotherapy affect management of cancer?

Answer 2

If radiotherapy is given for the head/neck, it may have significant impacts on the ability to eat & the sense of taste

Question 3

Why are side effects of treatment important to consider when managing cancer?

Answer 3

Nausea & vomiting is common with chemotherapy –> may hinder ability to keep food down

Question 4

Why is patient age important to consider when managing cancer?

Answer 4

Elderly patients tend to be poorly nourished & frail –> may not be able to tolerate treatment well

Question 5

What is one of the most important markers of morbidity, mortality, & ability to tolerate treatment?

Answer 5

Weight loss

Question 6

Which cancers have the most acute & chronic weight loss?

Answer 6

Cancers relating to GI tract

–> but these cancers also tend to respond to nutritional support best

Question 7

What is the relationship between body weight loss & total body protein loss?

Answer 7

Lean body mass = lean functional tissue mass

Whenever weight is lost, protein is also lost –> important to try maintain weight

Proportion of weight loss from original weight will indicate median survival time

Question 8

What is cachexia?

Answer 8

Wasting away of the body

Question 9

What is the pathophysiology of cachexia? (FOUR steps)

Answer 9

1. Tumour’s drive to produce pro-inflammatory cytokines
2. Increased pro-inflammatory response (interleukins, TNFa etc.)
3. Endocrine dysfunction
4. Increased protein degradation, decreased protein synthesis

Question 10

What FOUR things does cachexia lead to?

Answer 10

Decreased survival

Alterations in body image

Decreased function & strength

Caregiver distress

Question 11

What is precachexia?

Answer 11

Weight loss <5%

Anorexia & metabolic change

Question 12

What is cachexia? (stages)

Answer 12

Weight loss >5%, may have sarcopenia (decrease in skeletal muscle) or decreased BMI

Reduced food intake

Systemic inflammation

Question 13

What is refractory [resistant] cachexia?

Answer 13

Cancer disease procatabolic & unresponsive to treatment

Low performance score

< 3 months survival

Question 14

How is fat breakdown caused?

Answer 14

Tumour –> lipid mobilising factor –> fat breakdown

Question 15

How is anorexia caused?

Answer 15

Tumour –> cytokines –> hypothalamus –> anorexia

Question 16

How is increased energy expenditure caused?

Answer 16

Tumour –> cytokines –> hypothalamus –> increased energy expenditure

Question 17

How is the inflammatory response caused?

Answer 17

Tumour –> cytokines –> liver –> inflammatory response

Tumour –> hormonal changes –> skeletal muscle –> liver –> inflammatory response

Question 18

How is protein breakdown caused?

Answer 18

Tumour –> proteolysis inducing factor –> skeletal muscle –> protein breakdown

Question 19

Is glucose tolerance in cachexia increased or decreased?

Answer 19

Decreased

Question 20

Is insulin sensitivity in cachexia increased or decreased?

Answer 20

Decreased

Question 21

Is glucose turnover in cachexia increased or decreased?

Answer 21

Increased –> tumour uses glucose to develop

Question 22

Is hepatic gluconeogenesis in cachexia increased or decreased?

Answer 22

Increased

Question 23

Is serum lactate level in cachexia increased or decreased?

Answer 23

Increased –> more lactic acid produced for extra energy

Question 24

Is lactic acid cycle level in cachexia increased or decreased?

Answer 24

Increased –> more lactic acid produced for extra energy

Question 25

Is serum triglyceride level in cachexia increased or decreased?

Answer 25

Increased --> mobilisation of fat stores

Question 26

Is protein turnover in cachexia increased or decreased?

Answer 26

Increased --> proteolysis inducing factor --> breakdown of proteins to produce energy for tumour

Question 27

Is skeletal muscle catabolism in cachexia increased or decreased?

Answer 27

Increased --> proteolysis inducing factor --> breakdown of proteins to produce energy for tumour

Question 28

Which treatment is weight loss most common in?

Answer 28

All Chemotherapy Radiation Surgery Immunotherapy

Question 29

What treatment is fatigue most common in?

Answer 29

All Chemotherapy Radiation Surgery Immunotherapy

Question 30

What treatment is nausea & vomiting most common in?

Answer 30

Chemotherapy Radiation Surgery NOT immunotherapy --> more targeted

Question 31

What treatment is oral mucositis most common in?

Answer 31

Chemotherapy --> systemic cytotoxic Radiation --> local Immunotherapy NOT surgery --> cells in mouth not damaged since surgery is localised

Question 32

What treatment is taste disturbance most common in?

Answer 32

Chemotherapy | Radiation

Question 33

What treatment is constipation most common in?

Answer 33

Chemotherapy

Question 34

How does physical impairment of swallowing contribute to malnutrition in cancer? (FOUR points)

Answer 34

Effects on chewing/swallowing mechanisms Reduction in saliva production (xerostomia) Radiation-induced or chemotherapy-induced mucositis (painful to eat) Surgical interruption of swallowing mechanism

Question 35

How does alterations in physiology contribute to malnutrition in cancer? (THREE points)

Answer 35

Malabsorption/maldigestion due to tumour or therapy Constipation/GI immotility Removal of part of GI tract

Question 36

How does insufficient dietary intake contribute to malnutrition in cancer? (TWO points)

Answer 36

Suppression of appetite (nausea, vomiting) Food aversion

Question 37

What is enteral feeding?

Answer 37

Any method of feeding involving GI tract to deliver nutrition May involve oral or NG tube

Question 38

How is food delivered parenterally?

Answer 38

Simplest building block Protein - amino acid Carbohydrate - glucose Fat - fatty acids, triglycerides & combination Micronutrients - vitamins, minerals (eg. iron, calcium, zinc), trace elements (eg. boron) Fluid balance - electrolytes