We report performance status in oncology—but not nutritional status?

Abstract

Performance status (PS) scales are used routinely in clinical oncology to evaluate functional status and help direct treatment decisions. PS is also used to determine research protocol eligibility, indicate treatment response, and evaluate toxicity in oncology clinical trials. Malnutrition (like poor PS) is associated with adverse outcomes such as lower tolerance to anti-tumor treatment, poor quality of life, and decreased survival. Nutritional status is therefore arguably as important as PS for cancer outcomes. Despite well-documented adverse consequences for patients, malnutrition also often goes undiagnosed until severe depletion is evident. If the predictive importance of nutritional status is comparable to PS, why is nutritional status not routinely used along with PS to guide treatment decisions? There is compelling evidence to support the predictive abilities of both PS and nutritional status in cancer outcomes and treatment decision-making. Perhaps, PS may be a proxy for nutritional status. Nutritional status might also serve as an effective tool for patient selection and stratification in oncology trials. Together with PS, it might provide important and distinct prognostic information; we propose both should be routinely included in outcome studies. The extent to which impaired PS may be a surrogate for malnutrition warrants investigation. Given its comparable importance to PS, it is inexcusable that nutritional status is not given the prominence it deserves as a key patient-reported outcome.