Cancer Nutrition in Cancer Care: A Brief, Practical Guide With a Focus on Clinical Practice
Question: Are cancer patients receiving appropriate nutritional screening, assessment, and interventions?
SUMMARY ANSWER: Cancer Nutrition plays a crucial role for patients with cancer; however, nutritional problems are often under-prioritised, underdiagnosed, and undertreated, thereby affecting treatment outcomes and quality of life
WHAT WE DID: We summarised the clinical aspects of the available evidence-based guidelines and turned them into a practical approach that healthcare professionals may use.
WHAT WE FOUND: If healthcare providers are aware of nutritional issues, the prevention, delay, treatment, or even reversal of sarcopenia may be feasible.
Role of Nutrition in Cancer Prevention
REAL-LIFE IMPLICATIONS: Prevention, early identification of at-risk patients, accurate diagnosis, personalised intervention, and follow-up are cornerstones of managing malnutrition and its consequences: sarcopenia and cachexia.
Cancer nutrition plays a crucial role in cancer care. It affects treatment tolerability, outcomes, and quality of life. However, a focus on nutrition still needs to be improved among oncologists because of insufficient training in nutrition topics received during graduate and postgraduate training and an underestimation of its importance. In addition, the consequences of the disease and its treatment, such as anorexia-sarcopenia cachexia, are still often overlooked, underdiagnosed, and undertreated.
Malignant disorders are one of the leading causes of morbidity and mortality worldwide. Significant improvements in cancer treatment (surgery, systematic treatment, radiotherapy) have been achieved over the past 20 years because of multimodal therapies, improving cure rates and prolonged survival in the palliative setting. Based on the facts mentioned above, it is anticipated that healthcare systems worldwide will face a significant increase in the number of patients, especially older patients. Therefore, acquiring appropriate competencies in clinical cancer nutrition and a multidisciplinary team approach is essential so that all physicians and healthcare professionals can provide optimal nutrition as an integrated part of cancer treatment.
There is still a lack of focus on cancer nutrition among physicians and healthcare professionals because of the underestimation of its importance and insufficient training in nutrition topics being given during graduate and postgraduate training. The severity of weight loss is an independent predictive factor for shorter overall survival; about 10%-20% of all cancer mortality is directly related to malnutrition rather than underlying cancer. Personalised intervention and follow-up are cornerstones of managing malnutrition and its consequences: sarcopenia and cachexia.
Ageing, genetic and lifestyle factors, chronic diseases (e.g., cancer, chronic obstructive pulmonary disease, chronic heart failure, infectious diseases), and even acute conditions may accelerate sarcopenia. The following results are impairment in activities of daily living, loss of independence, mobility disorders and increased risk of falls and fractures, cognitive impairment, lower quality of life, increased risk of chemotherapy toxicities and mortality, and more prolonged hospital admissions and higher hospital costs.
In addition, patients with cancer are at significant risk of developing cancer-associated cachexia and anorexia syndrome (CACS). In addition, CACS is a multifactorial condition characterised by the ongoing loss of skeletal muscle and fat that cannot be fully reversed by conventional nutritional support, leading to progressive functional impairment.
Obese patients developing sarcopenia are at higher risk of being overlooked because they have a high body mass index, and the loss of skeletal muscle is not apparent. The geriatric population, especially older patients with cancer, are at increased risk of developing sarcopenia or even the acceleration of pre-existing sarcopenia leading to increased vulnerability; this is called the frailty syndrome.
Screening for cancer nutrition problems, assessing muscle mass or function, and guided interventions related to nutrition and physical performance is crucial in older cancer patients who have been treated with surgery, systemic treatment, or radiotherapy. This comprehensive approach— including assessment and intervention—is called comprehensive geriatric assessment. Its use is highly encouraged by leading cancer societies, such as the International Society of Geriatric Oncology and the ASCO.
PRACTICAL NUTRITION GUIDANCE: METHODOLOGY
To address cancer-related malnutrition and provide a straightforward, simple approach to tackling this critical and complex issue in daily clinical practice, a Nordic expert panel has prepared an easily applicable practical guide (Data Supplement, online only) based on the European Society for Clinical Nutrition and Metabolism guidelines and the Global Leadership Initiative on Malnutrition (GLIM) criteria.
The multi-professional Nordic expert panel consisted of a dietitian and a clinical nutritionist (a geriatrician) from Sweden, two clinical oncologists from Finland and Denmark, and a palliative care specialist from Norway. In addition, one in-person meeting and a video conference were held between April and October 2019, followed by email communication to discuss the available evidence in the field and prepare the expert opinion document.
CONTINUUM OF CARE IN NUTRITION
Diagnostic Workup
When the suspicion of malignancy arises, screening or assessment, intervention, and periodic evaluation—the so-called nutrition care process, should ensure appropriate cancer nutrition and be offered to patients in parallel with cancer care. The multidisciplinary tumour board should generally include dietitians and clinical nutritionists, as is the routine in many teams caring for patients with upper GI and head and neck cancers. The concept that cancer nutrition is an essential part of cancer treatment and not an additional add-on service must be widely disseminated among healthcare professionals caring for patients with cancer originating from all anatomical sites.
The Diagnosis of Malnutrition According to the GLIM
The considerable work of the GLIM working group has resulted in a global consensus concerning the definition of the criteria for the diagnosis of malnutrition in the clinical setting. The GLIM criteria involve a two-step approach. Step 1 is to identify at-risk patients using a validated screening tool (e.g., NRS-2002, MNA-SF, MUST, etc.).
Screening should be repeated periodically if the patient has a risk of weight loss or malnutrition. • Early identification of nutritional deficits • Solving all reversible causes of malnutrition • Brief and personalised advice • Optimal supportive care Nutritional assessment • Professional counselling: dietitian • Nutrition care plan Oral nutritional supplements Physical activity Artificial nutrition (enteral tubes, parenteral infusions), if needed (e.g., short bowel syndrome, oral mucositis, etc.) Follow-up periodical revaluation
The benefit of regular cancer nutrition screening in heterogenous cancer populations, there are some high-risk cancer sites (head and neck, upper GI) where close monitoring (e.g., weekly) of the patient’s nutritional status is essential. Other cancer sites with a lower risk of developing weight loss should be screened more individually according to the clinical situation, for example, with clinical deterioration because of disease progression and toxicities. From a more practical perspective, every patient with cancer should be screened, at least, at diagnosis of cancer, on hospital admission, on clinical deterioration, and when reporting weight loss while receiving systemic treatment, radiotherapy, or surgery.
Step 2 for patients at risk is to assess for confirmation of the diagnosis of malnutrition and determine severity grading. As described in the Data Supplement, the diagnosis of malnutrition according to GLIM requires the combination of at least one phenotypic criterion: weight loss, underweight, or low muscle mass, with at least one etiologic criterion: reduced food intake or malabsorption or high disease burden or inflammation. The result of these assessments will guide the interventions, and nutritional counselling with a dietitian is therefore crucial in this process.
The nutrition care and intervention plans demand close cooperation with the treating physician and caregivers and should also consider patient preferences. The results of interventions should be regularly monitored and reassessed at adequate intervals (e.g., weekly, fortnightly, three-monthly) depending on the patient’s nutritional risk and clinical situation.
Responsibility: The Role of the Key Person
It must be remembered that everyone’s responsibility is nobody’s responsibility. This is why every unit treating patients with cancer must appoint a key person responsible for nutrition. This person should be engaged in nutritional issues and have an in-depth understanding of clinical nutrition.
CLINICAL SCENARIOS INFLUENCING THE AIM AND INTENTION OF THE NUTRITIONAL TREATMENT
Curative Treatment and Life-Prolonging Palliative Treatment
Patients receiving antineoplastic treatment and whose GI function is intact should receive individualised nutritional counselling by a registered nutritionist and dietitian concerning energy and protein needs, lifestyle, eating habits, and personal preferences that the stage of the disease and treatment goal should individualise. All reversible symptoms such as nausea or vomiting, stomatitis, diarrhoea, pain, depression, and oral or oesophagal fungal infection that affect nutrition should be addressed and alleviated.
The patient and caregivers must understand the importance of the intervention and should be actively involved in the decision-making process, with higher motivation and increased adherence to the treatment plan and recommendations.6 Radiotherapy of the head and neck, upper GI tumours, and thoracic malignancies may result in numerous adverse effects (e.g., xerostomia, mucositis, swallowing difficulties, pain); enteral feeding using nasogastric or percutaneous tubes is recommended in such cases. If oral or enteral feeding is not possible, parenteral nutrition may be an option in highly selected cases. The nutritional targets are as follows: energy 25-30 kcal/ kg/d and protein 1-1.5 g/kg/d.
Palliative Treatment for Symptom Relief
The purpose of the treatment in this situation is to improve quality of life rather than prolong survival; therefore, more attention should be given to patient preferences. Treatment options, the expected benefits, and toxicity issues should be discussed with the patient and caregivers. In addition, individual nutritional counselling and adequate supportive care may contribute to increased quality of life and satisfaction among patients and caregivers.
Conclusion
For patients who are on cancer treatment, the goal is maximum comfort. In conclusion, Cancer nutrition plays a crucial role for patients with cancer; however, nutritional problems are often under-prioritised, underdiagnosed, and undertreated, affecting treatment outcomes and quality of life. This brief evidence-based guidance focusing exclusively on the practical aspects of the daily routine in oncology will help healthcare professionals improve patient care.
