The ensuing piece looks at the role of nutrition in the management of childhood cancer. I will be using materials from a paper by Pedretti et al. Role of Nutrition in Pediatric Patients with Cancer. Nutrients 2023, 15, 710.

Children with cancer are at high risk of nutritional deficits due to cancer itself, the toxicity of therapies, and their increased physiological requirements. Nutritional status (NS) during cancer therapies affects several clinical outcomes, such as overall survival (OS) and quality of life (QoL). NS influences the risk of morbidity and mortality both during and beyond the treatment of cancer, impacting the long-term health of survivors.

Undernutrition and malnutrition are risk factors for the development of infections. High blood sugar (hyperglycemia) which is a complication of the therapies used in the treatment of paediatric cancer patients is associated with an increased risk of infections and reduced survival in pediatric cancer patients. Long-term health outcomes are influenced by late-treatment-related effects, such as endocrinopathies, reduced bone mass, metabolic syndrome, cardiovascular disease, obesity, and hypertension.

Children are at a growth and development stage and require additional energy. Undernutrition problems, during this critical phase, may compromise proper growth, puberty and the correct development of the child, and balanced body composition.

The gut microbiome (GM) plays an important role in response to cancer therapy. Chemotherapy causes gastrointestinal (GI) toxicity, with changes in the normal bacterial flora, determining dysbiosis and contributing to the patient’s undernutrition. Foods considered important are those that modulate microbiomes, restore eubiosis (a balance in the gut flora), provide adequate nutrition, and even modulate the efficacy of cancer treatment.

The foregoing underscores why nutritional follow-up should become an integral part of the care pathway.

Pathogenesis of malnutrition in children with cancer:

Undernutrition in pediatric cancer patients is caused by a combination of factors, including the underlying disease, host inflammatory response, side effects of cancer therapy, and increased metabolic demands. These factors lead to changes in dietary intake, physical activity levels, and ratio of lean to fat mass, resulting in an alteration of the energy balance.

In cancer patients, there is a microenvironment of proinflammatory cytokines released by the tumour that causes accelerated mobilisation and oxidation of energy substrates, increased lipolysis, and loss of whole-body proteins. Cytokines may also act directly on the central nervous system (CNS), affecting appetite and increasing energy expenditure.

Furthermore, each type of cancer therapy, such as surgery, radiation therapy (RT), and chemotherapy (CHT), can produce several specific side effects. The combination of these therapies, which occurs in most therapeutic protocols, affects the nutritional status (NS) by decreasing appetite and oral intake or inducing nausea and vomiting. This can lead to loss of fluids, alteration of electrolytes, and deficiency of proteins and macro- and micro-nutrients.

Cytotoxic effects of chemotherapy (CHT) and radiotherapy (RT) can cause mucositis, which can affect the mucosa of the oral cavity and gastrointestinal (GI) tract. Lesions of oral mucositis are often very painful and compromise oral intake and oral hygiene, increasing the risk of local and systemic infections. Cellular oxidative stress is associated with both dietary intake and cancer therapy.

Skeletal mass:

In cancer patients, depletion of skeletal muscle happens due to an altered balance between synthesis and degradation of proteins and increased myocyte apoptosis (programmed cell death of the cardiac muscle cells). Loss of lean body mass can occur rapidly in paediatric cancer patients, leading to significant alterations, such as reduced muscle strength, weakened immune function, delayed wound healing, and increased morbidity.

This loss of lean mass may be accompanied by an increase in body fat stores, as seen with large and prolonged doses of glucocorticoid therapy. GCS can promote central fat accumulation, reduce adipocyte (specialised cells for the storage of fat) insulin sensitivity, and inhibit growth hormone (GH) responses.

Additional energy requirements:

In pediatric cancer patients, there are additional energy requirements compared to adults, as children are in a phase of growth and development. If these requirements are not met, the linear growth pattern may be compromised. Linear growth can be adversely affected by endocrine complications due to the disease itself as well as by the treatments used. GH deficiency (GHD) is the most common pituitary disorder in pediatric cancer patients, and it is more pronounced after craniospinal radiotherapy for brain tumours and for total body radiotherapy for bone marrow transplantation resulting in linear growth failure.

Evaluating nutritional status in children with cancer:

It is important to assess NS at diagnosis and to monitor NS during treatment as well as during survivorship. This is because, if the initial assessment is not carried out promptly at diagnosis, there is a risk of having results altered by the procedures and therapies used. Nutritional assessment should consider the NS of the patient, GI function, intensity of treatment, and current or expected side effects of treatment. Children receiving intensive treatment or at high risk of malnutrition should be evaluated at a maximum interval of 3–4 weeks. Children on less intensive treatment should be optimally evaluated at an interval of 3 months and 6 to 12 monthly intervals during the maintenance phase of treatment. More frequent reassessments are needed in children admitted to intensive care units (ICU).

Patients without nutritional risks can be evaluated every 6 months during the first year of follow-up and yearly after the first year. Well-nourished patients with nutritional risk factors (i.e., inadequate eating habits, sedentary lifestyle, hypertriglyceridemia, high cholesterol levels) should be evaluated every 3 months during the first year, every 6 months until the fifth year, and then annually.

Undernourished children require monthly assessments until they achieve normal NS. Obese children need revaluation every three months, every three months during the first year, every six months until the fifth year, and then annually. Undernourished children require monthly assessments until they achieve normal NS. Obese children need revaluation every 3 months.

Polyphenol-rich food:

Poor nutritional status and malnutrition during and following paediatric cancer treatment are linked with an increase in adverse outcomes of higher relapse and lower survival rates. Research into childhood cancer therapies focuses on novel strategies to improve their efficacy and further improve survival outcomes in childhood cancer patients.

Polyphenols have been studied for their beneficial effects on health, particularly as cancer-preventative agents.

Polyphenols play a complementary role in improving the effectiveness of cancer therapy. These include the induction of apoptosis, stimulation of immune system function, anti-inflammatory effects as well as multifaceted effects on the cellular signaling system. Cocoa is an excellent source of polyphenols.