Nutrition and the cancer patient Flashcards
10 most common cancers?
Prostate Lung Bowel Bladder NHL Malignant melanoma Kidney Oesophagus Leukaemia Brain tumours Other sites
What are the three most common cancers in men?
Prostate, lung and bowel
Account for 50% of male cancers
What are the three most common cancers in women?
Breast, lung and bowel
Over 50%
Which cancer accounts for most deaths?
Lung
How effective is nutritional support in lung cancer therapy?
Little evidence that dietary therapy in patients with lung cancer undergoing radiotherapy has an effect on patient or clinical outcomes- randomised controlled trials are needed
Which cancer patients are at high risk of weight loss?
Upper GI: stomach, pancreatic (secretions affected and cytokines released by tumours causing cachexia), head and neck
Medium- Prostate, colon and lung
Low- Breast, sarcoma and favourable NHL
What are the consequences of weight loss?
Reduced immunity Impaired muscle function, weakness Impairments to organ functions e.g. cardiac and respiratory Reduced mobility, loos of independence Reduced quality of life
What does the therapeutic index dictate?
Ability of patient to cope with toxic treatment that they are given
What is therapeutic index scaled to?
Weight, height, body surface area +/- GFR, +/- blood levels
What does too much therapy lead to?
Toxicity
What does too little therapy lead to?
Ineffective treatment
What is the greatest risk factor for response to therapy?
Sarcopaenia
What is sarcopaenia?
Loss of muscle mass
In what way is the relationship between sarcopenia and txicity a two way process?
Toxicity aggravates loss of weight and muscle
Weight loss and sarcopenia enhance toxicity
What is sarcopenia associated with?
More treatment delays
Dose reductions
Termination of treatment
Decreased OS in age, sex, stage and performance matched patients
What are the 5 main causes of malnourishment in lung cancer patients?
Iatrogenic causes of decreased intake Inadequate symptom control Site of tumour- functional and physiological causes of malnutrition Increased metabolic rate Cancer cachexia
What iatrogenic causes of decreased intake are there?
Decreased intake, increased expenditure and increased losses
Surgery- pain and fatigue, SOB
RadioTx: odynophagia (painful swallowing, fatigue, dysgeusia (altered taste) due to low saliva production all cause patient to eat less
Chemotherapy:
-Fatigue, nausea, anorexia and dysgeusia
-Vomiting and bowel changes (directing chemo at absorptive surfaces of gut will cause diarrhoea)- energy losses
- Infection will cause increase expenditure
-Mucositis
What is the relationship between symptoms and amount of weight loss?
Weak significant association
What are the common symptoms?
Most common to least: No appetite Early satiety Pain Taste changes Nausea Dry mouth Constipation Vomiting Diarrhoea
Which sites of tumours can lead to weight loss?
GI function/motility- changes affecting absorption of food
Obstructions of tumours in GIT- in head and neck cancer- difficult to eat
Malabsorption- cancer/mets in small intestine
What happens to BMR in vast majority of cancers as cancer progresses?
It increases
What are the two different definitions of cachexia?
Multifactorial syndrome that leads to ongoing loss of skeletal muscle with/without loss of fat mass. Can’t be fully reversed by conventional nutritional support and leads to progressive functional impairment
Specific metabolic response brought about by the presence of tumour, either from the tumour itself or its metabolites and stimulation of immune/acute phase response.
What defines an increased inflammatory response/status?
Increased CRP, IL-1, IL-6, IL-10 and TNF-alpha
What are the symptoms of cancer cachexia?
Reduced food intake/anorexia
Fatigue
Weight loss- muscle and fat
Weakness
Impaired immunity
Can be masked by oedema or obesity- very important in certain cancers e.g. breast, people remain overweight
Early cancer patients less likely to have cachexia than metastatic patients
What are the key differences between starvation and cancer cachexia?
The key differences are in cachexia,glucose (lowered in starvation) and protein metabolism (not increased in starvation, protein is preserved) are elevated; and there is rapid weight loss (slow in starvation) due to increased energy expenditure
Give an overview of cancer metabolism?
Tumour uses glucose to fuel itself- via anaerobic metabolism. Therefore no ATP is generated, instead lactate is which is delivered to liver and reprocessed into pyruvate -> glucose
Increased glucose cycling causes protein to be pulled from muscle to mett tumours demand for glucose. Release of TNF causes an increased breakdown of muscle to fuel the cancer.
With so much glucose used by the tumour, the body relies on fat metabolism to fuel itself
This causes preferential loss of lean body tissue. Increased muscle turnover and decreased synthesis, upregulated proteolytic pathways come into play
Increased lipolysis is required for liver to convert lactate into glucose which is very energy costly. This fuels the liver
What are the stages of cancer cachexia?
Precachexia- weight loss is 5%. Anorexia and metabolic change
Cachexia- Weight loss is >5%.
or BMI<20 and weight loss >2%
or sarcopenia and weight loss>2%
Often reduced food intake and systemic inflammation
Refractory cachexia- Variable degree
Cancer disease both pro-catabolic and not responsive to anti-cancer treatment. Low performance score. <3m expected survival
What are the goals of nutritional support in cancer?
Depends on what you’re trying to do and where patient is in their treatment pathway and what is happening:
Prevent/treat cancer therapy related malnutrition and/or weight loss
Increase treatment efficacy
Increase strength and quality of life
What are quality of life scores determined by?>
Tumour site- 30%
Weight loss- 30%
Intake- 20%
When should artificial nutritional support be given (tube or IV)?
Moderatly-severely malnourished patients if given 7-14 days pre-op
Anticipated inability to ingest/absorb nutrients for 7-14 days in malnourished at risk patient receiving treatment
When should you not give artificial nutrition?
As routine adjunct to surgery or chemo
Terminal illness- Rarely results in weight gain or altered outcome
Between breast and lung cancer, which patients are at greater risk of wasting?
Lung
What are the dietary recommendations for a cancer patient?
Decreased saturated fat
Increased intake of fish
Variety is good- maximise essential vitamins and minerals
Increase carotenoid containing fruit and veg
Prostate- increase soy intake
Colorectal- increase fibre
What are the physical activity recommendations for cancer patients?
At least 30 minutes 5 or more days/week
Even modest amounts help -> dose-response relationship
Exercise to improve lean body mass most useful in GI, head and neck cancers
Exercise to control body weight and lose body fat most useful in breast cancer
Give summary points for lecture?
Malnourishment is common in cancer patients and multifactorial
Important for all team to consider early nutritional intervention
Important to effectively manage symptoms
Metabolic changes due to cancer can’t be reversed without treating underlying cause first
Nutritional support is important in- improving oral intake, help with symptoms and side effects, improve tolerance to treatments, improve rehab potential, enhancing quality of life
Improved detection and treatment result in increased numbers living with and beyond cancer which changes emphasis of advice for cancer survivors
Not a single disease and requires holistic approach
