Clinical Oncology Society of Australia: Position statement on cancer-related malnutrition and sarcopenia

3.1 Identifying cancer-related malnutrition and sarcopenia

Cancer-related malnutrition and sarcopenia are under-recognised and therefore under-treated conditions. Neither malnutrition nor sarcopenia should be associated exclusively with being underweight, as these conditions can be present at any body weight or BMI category including obesity.^{18, 29} Timely and accurate identification of malnutrition and sarcopenia in all clinical practice settings is essential to support the initiation of optimal multidisciplinary care for people with these conditions, and a subsequent reduction in disability, mortality and health care costs.^{3, 7, 30} This identification process, commonly known as screening, enables recognition of people with cancer as “at risk” or “not at risk” of these conditions.

Screening for malnutrition should be undertaken on all people with cancer at diagnosis, and repeated as clinically indicated throughout each modality of treatment (eg, surgery, radiation therapy, chemotherapy), post-treatment and surveillance.^{3, 24, 25} Where limited resources restrict the ability to screen all patients, resources should be devoted to ensuring those at highest risk are screened (Table 3). Malnutrition screening should be undertaken using a malnutrition screening tool validated in the setting in which it is intended for use.^{6, 24} A number of malnutrition screening tools have been shown to be valid and reliable for identifying malnutrition in people with cancer including the Malnutrition Screening Tool (MST), Malnutrition Universal Screening Tool (MUST), Malnutrition Screening Tool for Cancer Patients (MSTC) and the Patient-Generated Subjective Global Assessment Short Form (PG-SGA SF).³ The MST and MUST are most commonly used in Australia and can be self-administered or completed by any health professional.^{31, 32} Screening for malnutrition can be bypassed for people with a cancer diagnosis or treatment plan known to lead to high risk of malnutrition, for example, radiation therapy with or without chemotherapy to the gastrointestinal tract or head and neck area.^{6, 25} All people with cancer identified as being “at risk” of malnutrition following screening, or with a diagnosis or treatment plan that places them at high risk of malnutrition, should be referred to an accredited practising dietitian for a comprehensive nutritional assessment and initiation of appropriate treatment.^{3, 6, 24}

Screening for sarcopenia should be completed in all people with cancer at diagnosis and as clinically indicated throughout each modality of treatment (eg, surgery, radiation therapy, chemotherapy), post-treatment and surveillance. The SARC-F is a sarcopenia screening tool that has been well studied and validated in older adults.³³ The SARC-F has recently been validated for use in people with cancer, either alone or in combination with measurement of calf circumference for greater sensitivity.³⁴ All people identified as “at risk” of sarcopenia should be referred to an accredited practising dietitian and exercise specialist that is, accredited exercise physiologist and/or physiotherapist, experienced in the cancer setting and with knowledge of body composition science, for assessment of muscle strength, muscle mass and physical performance and initiation of appropriate treatment.

3.2 Assessing cancer-related malnutrition and sarcopenia

Nutrition assessment is recommended for all people with cancer identified as “at risk” of malnutrition following screening or with a cancer diagnosis or treatment plan known to lead to high risk of malnutrition for example, patients receiving radiation therapy to the oral cavity or gastrointestinal tract.^{6, 25} Nutrition assessment and malnutrition diagnosis should be completed by an appropriately trained health care professional such as an accredited practising dietitian or if not available, other allied health or medical professional. Nutrition assessment should be repeated as the clinical situation changes and incorporated into routine clinical consultations.³ Nutrition assessment should incorporate measures of involuntary weight loss, BMI, body composition, food intake and nutrient absorption, functional status and inflammation.³ The 2019 Global Leadership Initiative on Malnutrition (GLIM) has produced a consensus statement outlining the recommended assessment domains for a diagnosis of malnutrition including etiologic (reduced food intake or assimilation; inflammation) and phenotypic criteria (weight loss; low BMI; reduced muscle mass).¹⁵ The Patient-Generated Subjective Global Assessment (PG-SGA)³⁵ and Subjective Global Assessment (SGA)³⁶ are validated assessment tools that align with the GLIM criteria for diagnosing malnutrition and can be used to assess and diagnose malnutrition in people with cancer.⁶

Sarcopenia assessment is recommended for all people identified as “at risk” of sarcopenia following screening and is ideally performed at the time of cancer diagnosis and before an initial treatment plan is implemented. Reassessment should occur as the clinical situation changes and incorporated into routine clinical consultations during active treatment and then ongoing surveillance throughout the course of care. Sarcopenia assessment and diagnosis should be completed by an appropriately trained health care professional such as an accredited practising dietitian, accredited exercise physiologist, physiotherapist or other allied health or medical professional. Assessment should consider whether it is primary sarcopenia (age-related) or secondary sarcopenia (other causal factors).¹³ These causal factors may include: (a) Disease—secondary to a systemic disease especially where inflammation is present as in cancer; (b) Inactivity—sedentary lifestyle or disease-related immobility or disability; or (c) Malnutrition—as a result of inadequate energy or protein caused by anorexia, malabsorption, food insecurity or limited ability to eat.¹³

There is no global consensus on the diagnostic criteria for sarcopenia. Commonly used definitions include the European Working Group on Sarcopenia in Older People (EWGSOP) 1¹² and EWGSOP 2,¹³ and the Foundation for the National Institutes of Health (FNIH) Biomarkers Consortium Sarcopenia Project³⁷ (Table 4). However, these definitions and cut-points have been developed based on research in older adults and have not been extensively researched in cancer populations. Most research in cancer has assessed sarcopenia based on low muscle mass alone from computed tomography images using cut-points prognostic for poor survival.^{40, 44} The various methods used for diagnosing sarcopenia are presented in Table 4. Selection of assessment method may depend on patient factors, access to the required technical resources and the purpose of testing. Clinicians and researchers should understand the strengths and limitations of the assessment method being applied and understand these are not interchangeable.^{12, 13} Ongoing research will contribute to identifying cut-points relative to patient population and ethnicity.

3.3 Treating cancer-related malnutrition and sarcopenia

Treatment of cancer-related malnutrition and sarcopenia aims to provide adequate nutritional intake and participation in exercise in order to optimise body composition with a focus on preserving or improving lean mass and physical function, as well as assisting patients to complete cancer treatment.^{6, 25, 29} However, people with cancer commonly report unmet needs in regards to access and provision of nutrition and exercise advice for the management of their malnutrition or sarcopenia, and are seeking consistent care from health professionals across their treating team to address these needs.^45-48

Medical nutrition therapy that considers symptoms, social situation and treatment plan, has been found to improve nutritional intake, weight and patient-reported physical function and reduce treatment breaks and unplanned hospital admissions.^{3, 6, 25} Sufficient nutritional intake of energy and protein is required to treat malnutrition, with evidence-based guidelines recommending between 105 and 125 kJ/kg/day and between 1.0 and 1.5 g/kg/day in protein.³ Preliminary data suggest that in fact a higher protein intake of 2.0 g/kg/day may be required to combat muscle loss; however, this is not yet supported by sufficient research.¹⁷ Specific recommendations regarding the use and timing of initiation of medical nutrition therapy, including enteral and parenteral nutrition, and Enhanced Recovery After Surgery protocols are available for some cancer types including head and neck and upper and lower gastrointestinal cancers.^{3, 6, 24, 25}

For medical nutrition therapy to be optimally effective, it needs to occur alongside exercise intervention.⁴⁹ Exercise training provides the necessary support for nutrition intervention to improve (or prevent worsening) in body composition, specifically, preservation or increases in lean tissue, with or without changes in body weight.^{3, 50, 51} Resistance exercise is more effective than aerobic exercise at improving muscle mass and strength.⁵² However, aerobic exercise remains relevant as it also modulates muscle metabolism, insulin sensitivity and levels of inflammation in a way that could potentially aid in preservation of muscle mass and function.⁵² As such, in line with the most up to date Australian exercise prescription guidelines for people with cancer, individually prescribed multimodal exercise training (including targeted aerobic and resistance exercise) at moderate to high intensity, with emphasis on resistance exercise incorporating exercises for major muscle groups, is recommended.⁵²

Although promising, evidence is variable for the use of anabolic or appetite stimulating agents, such as progestins, or non-steroidal anti-inflammatory agents, and their use should be evaluated on an individual basis by the MDT or disease protocol.³ Supportive care screening to identify unmet needs, including symptom management and psychosocial needs, is important for a holistic approach.

Interventions are most effective when commenced early, with a focus on prevention or the treatment of mild to moderate malnutrition and/or sarcopenia.²² However, despite the evidence for treatment of cancer-related malnutrition and sarcopenia, consistent and equitable access to care is lacking.^{3, 47, 48} The potential benefit to the health system through implementing evidence-based treatment of malnutrition and sarcopenia is significant, estimated to be the equivalent of AU$800 000 per 100 000 population.^{27, 53} Detailed recommendations regarding evidence-based treatment for people undergoing different treatment modalities and for specific cancer diagnoses can be found in the relevant evidence-based guidelines.^{3, 6, 24, 25, 52}

3.4 Role of the multidisciplinary team

A multidisciplinary approach to identifying and treating cancer-related malnutrition and sarcopenia is essential. Alongside medical nutrition therapy, interventions that have been shown to contribute to optimising nutritional status and body composition include exercise, management of treatment side effects through optimising medications and the management of anorexia and dysphagia.^{3, 25} Frameworks, such as the team mental model, have been found to optimise team processes and functioning.⁵⁴ Multidisciplinary cancer prehabilitation and rehabilitation programs providing individualised care demonstrate capacity to improve nutritional status, muscle mass and strength, fatigue and performance status.^55-58 These interventions require the specialist skills of various MDT members as part of a coordinated approach to individualised treatment of cancer-related malnutrition and sarcopenia and can be accessed through acute hospital services, community-based services or general practices.

Guidance regarding optimal practice at a national level is expected to improve the management of cancer-related malnutrition and sarcopenia across health sectors. Implementation of the position statement recommendations within health services will require the support and training of multidisciplinary health professionals, health service managers and policy makers. The position statement recommendations and pathway provide a framework for achieving optimal care.