Nutrition during Cancer TreatmentMedical editor Guro Berge Smedshaug
Oslo University Hospital
Monitoring the patient's nutritional status is an important part of cancer treatment. The goal is to identify malnutrition as early as possible in order to initiate treatment as quickly as possible.
Measures include diet according to symptoms and the nutritional condition. The patient should be offered nutrition-rich food, snacks, nutritional drinks, tube feeding and intravenous nutrition.
Because cancer treatment breaks down both cancer cells and normal cells, the body requires an adequate supply of nourishment to increase growth of new cells.
In cancer patients, the sensation of hunger is not always present to the necessary degree. In these cases, it is important to take actions to improve the nutritional status of the patient. The nutritional condition is easiest followed by monitoring body weight over time.
- Cancer treatment (chemotherapy, radiation, surgery).
- Maintain nutritional status in order for the patient to have the best possible conditions for implementing treatment.
Subjective Global Assessment (SGA)
Subjective Global Assessment (SGA) is a scheme for classifying the patient's nutritional status.
Other tables that are frequently used are Malnutrition Universal Screening Tool (MUST), Mini Nutritional Assessment (MNA) and Nutrition Risk Score (NRS). In principle, these schemes are prepared in the same way as SGA, but they are not validated for patients with cancer.
Weight loss is one of the most important signs of change in nutritional status. A weight loss of more than 15% over the past 6 months or more than 5% over the last month is a significant and serious weight loss. If the weight loss occurs in combination with low BMI (body mass index) (< 20 kg/m2 for adults) and/or a food intake of less than 60% of the calculated requirement over the past 10 days, the patient will be malnourished or be at nutritional risk.
Calculation of nutrition and fluid requirements
Ambulatory patients: 30-35 kcal/kg/day
Bed-ridden patients: 25-30 kcal/kg/day
Elderly above 70 years: Recommended amount is reduced by 10%
Fluid requirement: 30-35 ml/kg/day
Nutritionally enriched diet / enrichment of food and beverages
Nutritional beverages may be used as a meal in itself or between meals. Nutritional drinks can be a more valuable snack than "normal" food, because it is often easier for the patient to drink than to eat. It has been shown that if nutritional drinks are introduced as snacks, it does not affect the energy intake during the main meals.
There are a number of ready-made nutritional drinks on the market. Some of the products are of nutritionally complete. They contain carbohydrates, protein and fat and are supplemented with all the necessary vitamins, minerals and trace minerals and possibly fiber. Some of these products can be used as the sole source of nutrition. The energy content varies from 85-200 kcal/100 ml and some products have a high protein content. Other nutritional drinks are supplement drinks adjusted to individual needs such as allergies, intolerance and special conditions associated with illnesses.
The products are also adapted to age, and the dose is determined individually by a clinical dietician/doctor.
Many patients prefer homemade nutritional drinks based on full fat milk, cream, ice cream, fruit and possibly flavor supplements. These are free of additives and have a fresher taste. The energy and protein content is close to the commercial products and at the same time they are more sensibly priced.
Tube feeding is preferable to total parenteral nutrition (TPN) when the digestive system is working. Nutrition supply to the intestine is more physiological. It protects against bacterial growth, maintains the intestine's mucous membrane structure and function, and promotes motility. Tube feeding involves less risk of metabolic complications.
Tube feeding is used in the event of
insufficient food intake (less than 60% of energy requirements) over the past 5-7 days despite oral intake
weight loss >2 % over the past week, >5 % over the past month or >10% over the past 6 months
danger of weight loss due to planned treatment
low albumin values (under 35 g/l, lower limit for normal area)
stenosis with feeding obstacles in pharynx/gullet
Tube feeding must not be used for the following conditions.
Paralysis or ileus of the alimentary tract
Short bowel syndrome
Serious acute pancreatitis
Obstruction of the intestine
Serious fluid problems
Tube feeding solutions
The tube feeding solution must be nutritionally complete because they shall be used as the sole source of nourishment. The most frequently used are standard (1 kcal/ml), fiber-containing (1 kcal/ml) or energy-rich (1.5 kcal/ml). There are also tube feeding solutions which are adapted to patients with digestion and absorption problems, patients with diabetes or lactose allergy, and intensive care patients.
Tube feeding solutions, which are adapted to cancer patients are energy-rich (1.5 kcal/ml). They contain extra omega-3 fatty acids, rich in MCT acid and enriched with extra vitamins and minerals. Recommended dosage is 500 ml/day.
Parenteral nutrition should only be used if food by mouth or tube feeding cannot be maintained. Parenteral nutrition can also be used as a supplement to tube feeding or ordinary food.
Precautions must be taken for kidney failure, heart failure, lung failure, large fluid and electrolyte loss, diabetes mellitus and liver failure.
The patient is classified as well-nourished, somewhat malnourished or seriously malnourished on the basis of information about weight development, food intake, symptoms and physical functioning. This classification has been shown to correlate well with more objective measurements of nutritional status and morbidity, mortality and quality of life.
Actions include individual adjustment of diet according to symptoms and nutritional status.
The end of the tube is often inserted into the stomach. In the event of poor gastric function, total gastrectomy or pancreatic resection, the feeding tube should be inserted in the duodenum or jejunum. The position of the feeding tube is vital for the choice of feeding-tube solution and mode of administration.
The most common solution is to insert the tube nasogastrically, but it can also be done through the abdominal wall (PEG).
It is preferable to use intravenous or parenteral nutrition as a supplement to oral/tube feeding instead of only TPN (total parenteral nutrition).
Central veins must be used for TPN with high osmolality.
Peripheral veins can be used for short-term parenteral nutrition. In this case, a large vein on the forearm is used and a small needle. Nutrition is then given as more diluted solutions.
ImplementationAll patients are weighed regularly (1–2 times each week). This is a prerequisite to being able to register changes in the nutritional status.
Varied and healthy food contributes to the growth of new cells and enhances the immune system.
- Fruit, berries and vegetables are rich in vitamins, minerals, antioxidants and fiber, which contribute to enhances the immune system and contributes to keeping the digestive system working.
- Fish, shellfish, poultry, meat, eggs, cheese, milk, beans and nuts are rich in proteins, which are the building blocks of new cells.
- Bread, rice, pasta, porridge and breakfast cereals supplement the diet with proteins, carbohydrates, fiber, vitamins and minerals.
- Oil, margarine, butter, mayonnaise products, nuts, cream, heavy cream, desserts etc. are fat and energy rich products, which are important to maintain the energy intake at a satisfactory level.
- Cancer patients also have a requirement for plenty of fluid, especially during treatment, to discharge waste.
Often, the patients must have an individually adjusted diet. In the event of lack of appetite, it is generally more important that you eat (enough food) than what you eat (the right food). It is beneficial to have small portions and for the food to be as abundant in energy as possible. These patients will often have a need for 6–8 small meals everyday to obtain their energy requirements.
Enrichment of food and drink is done in order to increase the energy content of the food product without increasing the volume. Full-fat products such as full-fat milk, cream, butter, heavy cream, mayonnaise, sugar, honey, eggs and cheese etc. are primarily used. Enrichment powders from pharmacies may also be used. Some powders are nutritionally complete, i.e. they contain everything the body requires in terms of energy and nutrients, while others only contain pure energy (carbohydrates, fat and/or protein).
Tube feeding is given continuously with a low drop rate or by interval/bolus administration (individually adapted meals with high drop rate).
When the patient's energy and fluid requirements are fulfilled, it will be decided whether the patient will be given bolus or continuous supply at night, in order to increase mobilization during the day. However, this requires that the patient does not have diarrhea, nausea or other complaints associated with the supply of nutrition.
For a running feeding tube:
- Every 4-8 hours, it should be aspirated in order to monitor the gastric emptying. This applies especially to immobile and weak patients.
- Weekly or more often, the nutrition program/fluid balance, evaluation, edema control, blood tests (albumin, K, Mg, P, blood glucose) should be monitored weekly or more often.
- Every 4-6 weeks, the tube should be changed. Alternate the uses of nostrils avoid irritation in the nose through prolonged feeding.
Experience shows that the use of infusion pumps causes fewer side effects and ensures correct volume and rate.
Initiation of tube feeding with bolus supply is only recommended
- if the patient been taking any food until the last 24 hours
- if the patient is taking some food and requires tube feeding for additional nourishment
It is recommended to use pumps for bolus supply for the first 1–2 days.
If the patient cannot tolerate bolus supply (vomiting, abdominal discomfort, nausea, diarrhea), reverting to continuous supply should be considered.
Tube feeding should always be administered continuously to very malnourished patients or if the tube end is located distally to the pylorus.
If the patient has a satisfactory nourishment status, begin with 100% of the requirement. If the patient is seriously malnourished, start with 80 % of the requirement and increase slowly to 100% over the course of three days.
The patient must be monitored closely in relation to
- electrolytes (potassium, phosphate and magnesium).
- infusion rate.
- twenty-four hour urine sample and fluid balance should be calculated daily.
- glucose in the blood and urine, and electrolyte in the blood should be examined daily at the start.
- liver tests, kidney function tests and triglycerides should be taken examined at least once every week.
For TPN treatment longer than 1 month, vitamins and trace elements should be examined.
The patient's nutrition status should be monitored at follow-up visits after the end of treatment.