New insights into medical nutrition therapy for cancer cachexia

The development of cachexia is common in people with solid tumours such as pancreatic, lung, gastric and colorectal cancer. Cancer cachexia has been implicated in the deaths of 30 to 50 percent of all cancer patients, as many die from the wasting associated with the condition. Nutritional support in patients with cancer whether in the form of oral feeding, enteral or parenteral nutrition has generally failed to either prolong survival, improve the outcome of conventional anti-neoplastic therapy, weight, lean body mass or functional outcomes. For many years there have been attempts to find novel ways of managing the nutritional issues facing these patients.\ud \ud The studies provide valuable new insights and evidence regarding the effectiveness of medical nutrition therapy in patients with cancer. A theoretical model depicting a four step cascade of events leading to evidence of the effectiveness of medical nutrition therapy developed by Splett (1996) was used as the framework for the research. New insights have been provided into valid and reliable nutrition screening and assessment tools (appropriate access to necessary care), nutrition intervention in terms of prescription and intensity of service (quality nutrition care), improvement in dietary intake, nutritional status, quality of life and body composition (intermediate, clinical and patient outcomes).\ud \ud The studies have shown that the screening tool developed by the malnutrition advisory group of the British Association of Parenteral and Enteral Nutrition should not be used to identify hospitalised patients with cancer who are at risk of malnutrition due to low sensitivity and specificity. The nutrition screening tool of choice remains the malnutrition screening tool (MST) which has previously been shown to be a valid and reliable nutrition screening tool for identification of patients with cancer who are at risk of malnutrition. Once identified, the patient generated subjective global assessment {PG-SGA) rather than subjective global assessment (SGA) is recommended as the most appropriate nutrition assessment tool to identify the level of nutrition deficit and guide the implementation of medical nutrition therapy. It is a more sensitive measure than SGA, as small changes in nutritional status can be identified. The PG-SGA score was found to be significantly correlated to quality of life as measured by the EORTC-QLQC30 questionnaire. It can therefore be used as a surrogate measure for quality of life in clinical nutrition practice \ud \ud The studies provide several new insights into nutrition intervention for patients with cancer cachexia. In addition to the recognised prescription of an increased protein and energy intake, pharmacological doses of eicosapentaenoic acid (1.5-2.0 g) in the form of a high protein and energy oral nutrition supplement may result in positive patient outcomes. Compliance with the prescription is a key component of medical nutrition therapy. Unless the patient is able to consume an adequate quantity of protein and/or energy, then improved outcomes will not result. Practitioners must be aware of the importance of compliance with the nutrition prescription and encourage patients to view food and/or supplements as an essential component of treatment, that is, food as medicine. The implementation of the nutrition intervention is also of critical importance. Frequent contact with the patient is required to provide the level of support necessary to achieve positive outcomes. Weekly review either by telephone or by face to face interview is required.\ud \ud The studies provide new insights into improvements in intermediate outcomes (improvement in protein/energy intake) that can be achieved with medical nutrition therapy. Intake of a minimum of 1.5 cans/day of a protein and energy dense oral nutrition supplement did not decrease habitual food intake. Many patients are concerned that oral nutrition supplements depress appetite at meals and are reluctant to consume supplements between meals. Practitioners can be confident in advising patients that this is not the case.\ud \ud The studies provide new insights into the range of outcomes that can be achieved with medical nutrition therapy - nutritional status, quality of life, body composition and survival. In a post hoc analysis, there was a statistically significant improvement in weight and quality of life and a clinically significant improvement in lean body mass in patients with untreated pancreatic cancer who were compliant with the nutrition prescription. These studies provide new evidence that positive patient outcomes in terms of survival can be achieved with weight maintenance in patients with cancer cachexia rather than weight gain, which is frequently advocated in this patient group. This may be a more realistic and positive treatment goal for patients with cancer cachexia. The studies provide new evidence that an oral nutrition supplement containing EPA has positive benefits on outcomes in patients with cancer cachexia receiving chemotherapy such as improved nutritional status, quality of life and body composition. Dietetic practitioners can focus on outcomes such as weight maintenance, maintenance or improvement in nutritional status and quality of life to demonstrate clinical effectiveness.\ud \ud Collectively, these studies provide valuable new insights into medical nutrition therapy for cancer cachexia and they have the potential to influence management protocols across several cancer groups such as pancreatic, lung and colorectal cancer as the mechanism for the development of cachexia is thought to be similar in these patients