PURPOSE:Loss of appetite is a common side effect of cancer and cancer treatments resulting in risk of malnutrition and cancer cachexia. This review aimed to systematically determine nutrition interventions that improve appetite and nutrition-related outcomes of adults with cancer undergoing cancer treatments, and to identify appetite assessment tools used to measure appetite. METHODS:Inclusion criteria included randomised controlled trials of adults with cancer undergoing chemotherapy, radiotherapy or immunotherapy treatments, nutrition interventions and appetite assessed by an appetite assessment tool or quality of life tool. The search strategy was applied to four databases and two researchers systematically assessed for eligibility. Following data extraction, quality of the included library was assessed using the Quality Criteria Checklist: Primary Research. A narrative synthesis of results was undertaken. RESULTS:After title/abstract screening, 24 full texts were assessed for eligibility; five trials of n = 472 participants were included in the final library. Nutrition interventions that improved appetite were oral nutrition supplements, fish oil supplements and dietary counselling. Appetite was assessed via visual analogue scales (n = 1) and EORTC QLQ C30 questionnaire (n = 4). Quality was assessed as neutral in 2 studies and positive in 3 studies. CONCLUSION:The use of oral nutrition supplements and dietary counselling and increases in EPA from fish oil supplementation improved the appetite and nutrition outcomes of patients with cancer undergoing cancer treatments. Validated assessment tools in the oncology setting are needed to determine which nutrition interventions positively influence appetite outcomes.