Purpose Malnutrition severely impacts tolerance to anticancer therapies, but any relationship with overall survival (OS) at the time of solid tumour diagnosis in outpatients in the USA remains unclear.

Methods This retrospective study evaluated 3562 patients who completed the Malnutrition Screening Tool (MST) at diagnosis, identifying the relationship between MST risk, a validated tool evaluating anorexia and weight loss, and OS. MST score of ≥2 of 5 was classified as high malnutrition risk (H-MST). Kaplan-Meier techniques and Cox proportional hazards models were used to analyse OS in H-MST versus low malnutrition risk (L-MST).

Results In the unadjusted models, MST risk was individually associated with OS. Multivariable regression confirmed that MST risk remained independently prognostic for OS after controlling for key confounding variables, HR=1.51 (95% CI: 1.33 to 1.72). The H-MST group had shorter OS (50-month survival rates: 69% L-MST vs 60% H-MST).

Conclusion MST risk at diagnosis is an independent prognostic factor for OS. H-MST risk is associated with shorter survival in a broad cohort of solid tumour oncology outpatients.