Nutrition & Cancer: Guide for Healthcare Professionals

How cancer influences weight and nutritional requirements

In this section you can read about the following topics:

• Cancer Cachexia
• Metabolic Changes
• Identifying Patients at Risk of Malnutrition
• Treatment Objectives • Weight Loss
• Loss of Appetite • Nausea & Vomiting
• Sore Mouth • Taste Changes
• Swallowing Difficulties • Diarrhoea
• Constipation

Cancer and its treatments can have a number of direct effects on patients’ weight, nutritional requirements and dietary intake. Certain treatments, for example chemotherapy, radiotherapy and biological therapy, can cause side effects such as loss of appetite, nausea, vomiting, diarrhoea, constipation, sore or dry mouth and taste changes which may limit oral intake and lead to weight loss.

Following surgery, patients will have increased requirements for protein and energy to help with repair and wound healing. The tumour can have an effect on weight loss and dietary intake by:

a) Producing chemicals which can cause muscle breakdown or loss of adipose tissue, and/or b) Causing a physical blockage in the gastrointestinal tract.

Cancer Cachexia

Cancer cachexia is a severe form of malnutrition associated with a poor prognosis and characterised by:

Anorexia (loss of appetite and early satiety)
Asthenia
Weight Loss
Anaemia
Muscle wasting

In pancreatic cancer, 85% of patients are cachectic at the time of diagnosis and have experienced a 15% weight loss in the 3 months prior to diagnosis.^3,5
Cancer cachexia is most common in people with advanced illness and it accounts for approximately 20% of cancer deaths.⁶

A number of metabolic changes occur in patients with cancer cachexia which lead to weight loss:

Increased metabolic rate: this contributes to overall negative energy balance and accelerates weight loss
Loss of skeletal muscle: this arises from a fall in protein synthesis and an increase in protein degradation
Loss of fat mass (adipose tissue)

It is worth noting that in cancer cachexia there is a loss of lean body mass and fat mass. Studies have shown that food intake does not correspond with the degree of malnutrition in cancer cachexia and attempts to increase dietary intake through dietary counselling cannot halt the wasting process. This indicates that there are metabolic changes occurring in the body, unrelated to reduced dietary intake, which lead to loss of muscle and fat mass.

Chemicals responsible for metabolic changes

There are a number of chemical substances which are thought to be responsible for the metabolic changes seen in patients with cancer cachexia. There may be an increased production of pro-inflammatory cytokines by the patient which can lead to muscle protein breakdown and weight loss.

The tumour itself is also thought to produce a number of chemicals which can lead to the breakdown of protein and fat stores in the body, for example:

Lipid-mobilising factor (LMF): which directly stimulates lipolysis and increases energy expenditure
Protein-mobilising factor (PMF): which can directly mobilise fatty acids and amino acids from adipose tissue and skeletal muscle
Proteolysis inducing factor (PIF): causes muscle protein degradation and decreases muscle protein synthesis

Identifying Patients at Risk of Malnutrition

It is important to identify patients as risk of malnutrition or who are already malnourished in order to intervene and present the consequences of malnutrition. Nutritional screening is your first step in identifying people at risk of malnutrition.

Objectives of Nutritional Treatment

Patient treatment goals Your objectives for nutritional treatment should be based on the different factors that are influencing a patient’s dietary intake and nutritional requirements. This requires frequent assessment of nutritional status and any factors which may contribute to its deterioration.

Nutritional treatment should aim to support the patient and will vary depending on whether a patient is in the active treatment, post-treatment, remission or palliative care phase. During active treatment, post-treatment or remission nutritional interventions should aim to improve nutritional status and prevent its deterioration after treatment. For those patients in the palliative phase, nutritional support can help to maintain a better quality of life. The focus should also be on encouraging patients to eat their favourite foods, with an emphasis on food as a source of pleasure.

Objectives of nutritional treatment

To preserve muscle mass
To improve the immune system
To improve tolerance to treatments
To reduce the risk of surgical complications
To improve quality of life
Encouraging patients to eat well if they are experiencing
To maintain weight/prevent weight loss

Encouraging patients to eat well if they are experiencing . . .

Weight Loss
Loss of Appetite
Nausea and Vomiting
Sore Mouth
Taste Changes
Difficulty Swallowing
Diarrhoea
Constipation

Weight Loss

Encouraging patients to increase the energy and protein content of their diet using normal foods should be your first line dietary advice and can help patients to maintain their weight.

You may find that some patients are reluctant to eat foods high in fat or sugar because this opposes the usual healthy eating messages. It is important to emphasise that during their treatment, patients have different dietary needs therefore the general healthy eating guidelines do not apply.

The list below provides some suggestions for increasing the energy content of the diet.

Use full fat milk instead of semi-skimmed
Make fortified milk by adding 2-4 tablespoons of milk powder into 1 pint of full fat milk. Use this milk in place of regular milk such as in tea and coffee or on cereal
Mix grated cheese or cream into foods such as mashed potato, soups and casseroles
Add extra cream, ice-cream, evaporated or condensed milk to puddings
Use plenty of butter or margarine, spread it thickly onto bread or add a lump onto cooked vegetables
Try high-energy snacks such as nuts, cheese and crackers, dried fruit, full fat fromage frais and full fat yoghurts
If a patient feels full soon after eating, encourage them to eat smaller amounts more often. For example, try to eat every 2-3 hours
Suggest that patients drink only nourishing fluids, such as milky drinks or energy enriched smoothies. Water, tea, coffee or squash can make people feel full but they don’t provide a lot of energy. Advise patients that they can still drink tea, coffee or squash, but suggest that they have them after a meal

Loss of Appetite

The information below may help your patients to increase their dietary intake and improve their appetite.

Eat smaller amounts of foods high in protein and energy more frequently, suggest that they eat every 2-3 hours rather than having three large meals
Try high-energy snacks such as nuts, cheese and crackers, dried fruit, full fat fromage frais, and full fat yogurts
Prepare and store small servings of favourite foods in advance – then there will always be something ready to eat when they do feel hungry

Foods high in protein	Foods which can be added to meals to increase the energy content
Full fat milk Full fat yoghurts or fromage frais Cheese All meats poultry and fish Eggs Nuts and seeds Lentils beans and pulses	Full fat spread Margarine Cream Cheese Evaporated milk Condensed milk Jam, honey, marmalade Peanut butter Chocolate spread

Nausea and Vomiting

The following tips may help if your patients are experiencing nausea and vomiting.

Eat smaller amounts more often, for example try to eat every 2-3 hours rather than having three large meals each day
Dry, salty foods may help, for example dry crackers or plain crisps
Suggest that someone else cooks for them, as the smell of food can often make people feel nauseous
Cold or slightly warm foods, may be easier to tolerate
Avoid fried or fatty foods, or foods with a strong smell
Chunks of fresh or tinned pineapple can help to keep the mouth fresh and moist

Sore Mouth

Certain treatments such as chemotherapy and radiotherapy to the head and neck, can cause patients to have a sore or inflamed mouth, which can make eating and drinking very difficult, the following tips may help:

Drink plenty of liquids to help keep the mouth moist
Avoid citrus and acidic foods and drinks, such as orange juice
Cold or frozen foods can help the mouth feel better, for example flavoured ice-cubes, ice-cream or frozen yoghurt
Soft food or food that has been put in the blender may be easier to eat

Taste Changes

Patients undergoing chemotherapy or radiotherapy often experience taste changes during the course of their treatment. Some of the hints below may help patients to overcome these taste changes and allow them to continue to enjoy eating and drinking.

Suggest that patients avoid foods that taste peculiar to them, but re-try them every couple of weeks as their taste may have returned to normal
Add strong flavours to foods, such as herbs, spices and marinades to improve the taste. Sauces and gravies can also help
Try stronger versions of favourite foods such as mature cheese or smoked ham
Use plastic utensils if food tastes metallic
Patients should keep their mouth clean and brush their teeth regularly

Difficulty Swallowing

Some patients may experience swallowing difficulties during their treatment, for example during radiotherapy to the head and neck. Patients having chemotherapy may experience pain when swallowing.

The following suggestions may help if patients are experiencing swallowing difficulties:

Eat slowly and chew food thoroughly. Take small bites of foods and small sips of beverages
Eat smaller amounts more often, for example try to eat every 2-3 hours rather than having three large meals
Fine chop meat and vegetables in a food processor before or after cooking
Blend meat or vegetable casseroles or curries to make tasty soups
Avoid dry foods or foods that are hard to swallow, such as dry/tough meat, plain rice, bread, raw vegetables, dry biscuits, dried fruit or nuts
Add sauces, gravies, cream, butter, milk or custard to foods to soften them and to make them easier to swallow
If patients are experiencing weight loss suggest that they use milk or cream instead of water when mashing or blending foods
Thickened liquids or foods may be easier to swallow than thinner ones. An instant food and drink thickener such as Resource® ThickenUp® may help

Diarrhoea

Diarrhoea is a common side effect of some treatments, such as chemotherapy and radiotherapy to the abdominal area.

The following tips may help to manage diarrhoea:

Drink plenty of liquids throughout the day
Try to eat small, frequent meals and snacks
Avoid greasy, fried, spicy or very sweet foods
A soluble fibre supplement may also help, such as Resource® Benefiber®

Constipation

Some drugs, such as painkillers, can cause constipation. The information below may help to prevent and manage constipation.

Try to drink plenty of fluids. Water, prune juice and orange juice can help
Include foods high in fibre, such as fruit, vegetables, lentils, beans and pulses, wholegrain breakfast cereals, wholemeal bread, or add a fibre supplement to foods and drinks, such as Resource® Benefiber®
Try to do some exercise every day, such as a short walk

Nutritional support for patients undergoing surgery for GI and head and heck malignancies
Surgical patients are at an increased risk of post-operative complications such as hospital acquired infections which can lead to slower recovery and extended length of hospital stay.
Proactive management of infections in surgical patients has been shown to reduce complications and decrease overall cost of care.¹²

A number of clinical studies have found that using an immune-enhancing formula enriched with omega-3 fatty acids, arginine and nucleotides, such as Oral IMPACT®, peri-operatively in patients undergoing surgery for GI, head and neck malignancies, irrespective of their nutritional status, can result in:

Significantly fewer post-operative infections, such as
lower rate of wound infections, pneumonia, UTI’s and abdominal abscesses
Decreased hospital length of stay by > 2 days.¹²

The recent ESPEN Guidelines on Enteral Nutrition supported the use of an immune-modulating formula enriched with omega-3 fatty acids, arginine and nucleotides, by providing the following recommendations:.¹³

Unrelated to nutritional risk, immune-modulating substrates (arginine, omega-3 fatty acids and nucleotides) are recommended 5-7 days prior to surgery for cancer patients undergoing major abdominal surgery (Grade A)
Immune-modulating formulas should be used for patients undergoing major neck and GI surgery for cancer or severe trauma patients (Grade A)
Whenever possible administration of these supplemented formulae should be started before surgery (Grade C)
This should continue for 5-7 days (Grade C) after uncomplicated surgery