Dr Mark Brougham and Dr Raquel Revuelta-Iniesta co-chair the Cancer and Nutrition working group for Children and Young People, part of the National Institute for Health and Care Research (NIHR). They tell us more about the group, the importance of nutrition and what research is happening to improve nutrition for patients.
Who are we?
We are multidisciplinary, and include oncologists, nurses and dietitians with both clinical and research experience. Our aim is to improve nutrition for children and young people with cancer, at diagnosis, during treatment and throughout long-term follow-up.
Why is nutrition important for children and young people with cancer?
We all need good nutrition for normal growth, development and general wellbeing. Being malnourished means that the amount of energy, protein and other nutrients aren’t at ideal levels in our bodies, which leads to health problems. Usually, we think about under-nutrition where people are too underweight. However, there are some cancers which lead to weight gain, usually due to treatment.
Although patients may gain weight, this can mean less muscle mass, made worse by being less physically active. Both under- and over-nutrition can lead to a lack of important nutrients. Studies show that many young people with cancer have problems with nutrition when they’re first diagnosed. Unless, this is managed carefully, these may get worse during and after treatment. This is a particular concern in cancers that require more intensive treatments.
A balanced diet should include fruit and vegetables, pulses, wholemeal bread, lean meat, fish and poultry and should limit the intake of sugary drinks and foods.
These issues are important because nutrition can affect various aspects of cancer treatment. It’s well documented that children and young people with cancer who are well nourished react better to treatment and have improved outcomes. The way the body handles drugs, including chemotherapy, varies according to each individual body. Chemotherapy dosing is usually based on body weight, so if there’s weight loss, doses may be reduced, resulting in less effective treatment. Impaired nutrition can also negatively impact the immune system, which is already weakened by cancer treatment. Many children and young people with cancer need surgery and poor nutrition can weaken the body’s ability to heal wounds. Those with poor nutrition also report low energy levels and a reduced sense of wellbeing, affecting both psychological and physical health. Follow-up studies show that young cancer patients can also have long-term consequences of impaired nutrition, and these are often underrecognised and difficult to manage, as discussed below.
How do we measure nutrition status?
Nutritional screening is an important part of patient care, which includes measuring weight and height, to identify those at risk of becoming under-nourished and begin thorough nutritional assessments by a dietitian. Nutrition assessment in childhood cancer is an evolving process, looking into a child’s growth (body mass index (BMI) and body composition), blood markers, including micronutrients (vitamins and minerals), clinical history, treatment and likely side effects that might affect food intake.
Also, what children eat and other factors that might affect nutritional status should be assessed. Monitoring is essential in highlighting when and if further nutritional support is required.
Traditional measures of weight, height and BMI are used in practice to assess whether a child is growing how they should be, particularly during treatment. However, BMI has limitations and may not accurately reflect nutritional status. This is because loss of muscle mass often develops during treatment but can be accompanied by an increase in fat mass and fluid, which results in the patient’s weight appearing satisfactory. ‘Arm anthropometry’ is used to measure the circumference of the mid-upper arm to estimate muscle mass, the ’triceps skinfold thickness’ to estimate fat mass, and ’bioelectrical impedance’ to estimate body composition (muscle and fat mass).
These assessment methods are quick and non-invasive, and aren’t affected by fluid or tumour mass, giving a more accurate assessment. However, they take time and are performed less often. For children over two years old, diet quality and intake are assessed by performing a diet history, using a food diary or food record chart over several days, at home or on the ward. These can provide further information to help with nutrition support.
What can we do to support a patient with their nutrition?
How we improve nutrition depends on the patient’s nutritional status: under-nutrition or overweight, and the reasons for this. With under-nutrition, support aims to promote weight gain and growth. This may involve one or more of the following:
- adding extra nutrients or
calories to food - giving oral supplements
- giving nutrition direct to the stomach
or intestines through a tube - giving nutrition directly into the
veins, bypassing the gastrointestinal
tract, called parenteral nutrition.
This is given to those who have
issues with their gut function such
as severe mucositis and enteritis
We make decisions after a thorough nutritional assessment and discussions with the patient, families and the multidisciplinary team.
Healthy eating guidelines are important to minimise weight gain associated with steroids, which may be used in treatment, most commonly for those with acute lymphoblastic leukaemia (ALL). A balanced diet should include fruit and vegetables, pulses, wholemeal bread, lean meat, fish and poultry and should limit the intake of sugary drinks and foods. These recommendations can be very difficult to follow, particularly when patients experience taste changes and nausea due to chemotherapy and prefer high-energy, sweet or very salty foods. Expert advice is therefore essential.
Are there any issues after treatment?
Many studies show that children and young people who have finished treatment may have long-term issues related to nutrition. Patients are particularly at risk of being overweight and can develop ‘metabolic syndrome’. This describes a combination of excess weight, high blood sugar levels, high blood pressure and high cholesterol, which can lead to heart disease, stroke and type 2 diabetes. Those treated for cancer may also have less dense bones. These are all monitored during long-term follow-up of patients.
What research is happening to improve this area of care?
As cancer treatment advances and survival rates improve, more research now takes place in supportive care, such as nutrition, to help reduce side effects and improve quality of life. Research has mainly investigated how cancer and different types of treatment affect nutritional status, to understand more about when nutritional support is needed and what support is most effective. Some studies have compared the effectiveness of NG and PEG nutrition in young people having chemotherapy, but more studies are needed to provide evidence on what the best approach is in different circumstances.
Apart from vitamin D, micronutrient status isn’t routinely measured, due to limited research and difficulties in interpreting results. Emerging research suggests micronutrient deficiencies and toxicities are common during cancer treatment, and these may be associated with more side effects. However, more research is needed to find out what the ideal micronutrient levels are and how much supplementation should be recommended.
In the meantime, advice is based on national guidelines, such as a diet high in fruit and vegetables, which have been shown to decrease infection rates and mucositis in ALL patients. This is encouraging and highlights the need for more children- and family-centred dietary support.
Being overweight can affect how some drugs work, and therefore some patients may need extra support to lose weight. This approach differs to historical weight-focused, highenergy, high-protein diets for all young people with cancer, which doesn’t differentiate between nutritional needs of those with different diagnoses.
These newer, targeted approaches give insights into the impacts of diet and lifestyle changes early in treatment and show that support related to nutrition and activity can be provided early to help patients.
From Contact magazine issue 101 - Winter 2023
