Measuring cachexia—diagnostic criteria
Cancer cachexia is characterized by the loss of lean body mass with or without the loss of fat and is associated with increased susceptibility to treatment related toxicities, decreased quality of life, functional impairment, and increased cancer-related mortality. Uncontrolled symptoms which impair nutritional intake, metabolic derangements including elevated energy expenditure and increased catabolism, and chronic inflammation contribute to the development of cancer cachexia. Weight loss in cancer patients is not readily reversible by conventional nutritional support. The definition of cachexia and sarcopenia are evolving with time, as well as the assessment of weight loss in cancer patients. Clinicians should assess all cancer patients regardless of history of weight loss for risk for malnutrition at presentation and periodically throughout the trajectory of illness—pre-cachectic, cachexia, and refractory cachexia stage. For cancer patients with weight loss, assessments of BMI and percentage weight loss, symptoms which impact nutritional intake, quality of life, physical function, biological markers, energy expenditure, and body composition are ideally needed in order to measure cachexia and implement therapeutic interventions.