Prospective nutritional status and body mass composition assessment in patients with advanced NSCLC treated with immune checkpoint inhibitors.

8584 Background: The nutritional status of patients (pts) with advanced cancer seems to impact on immune cells activity against tumor cells. We aim to explore the prognostic role of nutritional status and body composition (BC) in pts with advanced non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs). Methods: From June 2021, we prospectively enrolled pts with advanced NSCLC treated with ICIs, as monotherapy or in combination with chemotherapy. Pts nutritional status at baseline was evaluated using the controlling nutritional status (CONUT) score (combining serum albumin, total cholesterol, lymphocyte count), and median daily fiber intake. Comprehensive BC evaluation was assessed by body mass index (BMI), SARC-F questionnaire, and bioelectrical impedance analysis (BIA). Data were correlated to progression-free/overall survival (PFS/OS). The predictive accuracy of the baseline parameters for 6-months PFS was assessed using receiver operator characteristic (ROC) analysis and the area under the curve (AUC). Results: Among 56 pts enrolled, median age was 72 years-old, 80% (N=45) were male, 83.9% (N=47) were treated with ICIs in first line, 60.7% (N=34) received ICIs as monotherapy, 100% (N=56) had an Eastern Cooperative Oncology Group Performance Status of 0-1, 46.2% (N=24) had a PD-L1 ≥ 50%. At a median follow up of 22.3 months (95%CI 16.1-26.7), pts with low CONUT score (≤4), characterized by good nutritional status, had longer PFS (HR 0.28, 95%CI 0.15-0.52, p4), meaning poor nutritional status. Pts with good daily fiber intake (≥20 g) had longer PFS (HR 0.48, 95%CI 0.26-0.91, p=0.02) compared to those with low fiber intake (<20 g). Considering BC features, no statistical difference was found in terms of clinical outcomes according to BMI. Pts characterized by low risk of sarcopenia with a SARC-F questionnaire score <4 had longer OS (HR 0.35, 95%CI 0.16-0.80, p=0.01), compared to those with a higher risk. Non-sarcopenic pts with high skeletal muscle index (SMI: skeletal muscle/height 2 ) (≥8.9 for males, ≥6.4 for females) assessed by BIA had longer OS (HR 0.43, 95%CI 0.20-0.05, p=0.04) compared to sarcopenic pts defined by low SMI. The AUC value for 6-months PFS, considering all baseline nutritional (CONUT score and daily fiber intake) and BC features (SARC-F questionnaire score and SMI) together with PD-L1 as a key discriminant for clinical treatment choice, was 0.83 (sensitivity = 0.81, specificity = 0.91). Conclusions: Baseline good nutritional status and skeletal muscle mass are valuable predictors of improved clinical outcomes in advanced NSCLC pts receiving ICIs. The study is still recruiting and underlines the need to improve pts assessment in terms of nutritional and BC phenotypes before ICIs start.