BackgroundCancer-associated malnutrition is associated with worse symptom severity, functional status, quality of life, and overall survival. Malnutrition in cancer patients is often under-recognized and undertreated, emphasizing the need for standardized pathways for nutritional management in this population. The objectives of this study were to (1) investigate the relationship between malnutrition risk and self-reported symptom severity scores in an adult oncology outpatient population and (2) to identify whether a secondary screening tool for malnutrition risk (abPG-SGA) should be recommended for patients with a specific ESAS-r cut-off score or group of ESAS-r cut-off scores.MethodsA single-institution retrospective cross-sectional study was conducted. Malnutrition risk was measured using the Abridged Patient-Generated Subjective Global Assessment (abPG-SGA). Cancer symptom severity was measured using the Revised Edmonton Symptom Assessment System (ESAS-r). In accordance with standard institutional practice, patients completed both tools at first consult at the cancer centre. Adult patients who completed the ESAS-r and abPG-SGA on the same day between February 2017 and January 2020 were included. Spearman’s correlation, Mann Whitney U tests, receiver operating characteristic curves, and binary logistic regression models were used for statistical analyses.Results2071 oncology outpatients met inclusion criteria (mean age 65.7), of which 33.6% were identified to be at risk for malnutrition. For all ESAS-r parameters (pain, tiredness, drowsiness, nausea, lack of appetite, shortness of breath, depression, anxiety, and wellbeing), patients at risk for malnutrition had significantly higher scores (P < 0.001). All ESAS-r parameters were positively correlated with abPG-SGA score (P < 0.01). The ESAS-r parameters that best predicted malnutrition risk status were total ESAS-r score, lack of appetite, tiredness, and wellbeing (area under the curve = 0.824, 0.812, 0.764, 0.761 respectively). Lack of appetite score ≥ 1 demonstrated a sensitivity of 77.4% and specificity of 77.0%. Combining lack of appetite score ≥ 1 with total ESAS score > 14 yielded a sensitivity of 87.9% and specificity of 62.8%.ConclusionMalnutrition risk as measured by the abPG-SGA and symptom severity scores as measured by the ESAS-r are positively and significantly correlated. Given the widespread use of the ESAS-r in cancer care, utilizing specific ESAS-r cut-offs to trigger malnutrition screening could be a viable way to identify cancer patients at risk for malnutrition.