Supplementary file 2_Nutritional ultrasound cut off for predicting complications and mortality in lung cancer patients: a multicenter longitudinal study from the VALONC project.docx

RF-CSA and RF-Y-axis showed the highest discriminative performance for GLIM-defined malnutrition, with AUCs of 0.706 and 0.713 in men and 0.814 and 0.804 in women, respectively. The corresponding RF-CSA cut-offs were 3.88 cm² in men and 2.78 cm² in women, whereas RF-Y-axis cut-offs were 1.09 cm in men and 0.95 cm in women. In men, RF-Y-axis was significantly associated with all-cause mortality (HR = 0.32, 95% CI: 0.15–0.71), whereas RF-CSA, RF-CIR, and RF-X-axis were associated with clinical complications.

No significant associations with mortality or complications were observed in women. A moderate agreement was observed between GLIM and PG-SGA (weighted κ = 0.51), suggesting that these criteria capture overlapping but not identical dimensions of malnutrition.</p>Discussion<p>Rectus femoris ultrasound may provide objective, sex-specific clinical information that complements the GLIM framework and traditional anthropometric assessments.

By identifying clinically relevant muscle waste, this bedside tool allows for the early detection of high-risk patients, potentially directing timely nutritional and rehabilitative interventions to improve survival and treatment tolerance in lung cancer.</p>