Diffusing capacity for carbon monoxide (DLCO) change and outcome in advanced non-small cell lung cancer (aNSCLC) treated with immune checkpoint inhibitors (ICIs).

Abstract

e20602 Background: Despite recent therapeutic advances, identifying effective prognostic markers in aNSCLC remains an unmet need. DLC) has shown prognostic value in non-oncological pulmonary conditions but is underexplored in predicting outcomes in aNSCLC. We aimed to evaluate the prognostic value of DLCO changes following treatment with ICIs. Methods: The NEUMOTOX study, a prospective observational study, enrolled aNSCLC patients undergoing treatment with ICI, with or without chemotherapy, from August 2022 to April 2024. DLCO was measured at baseline and at 3-6, 9, and 12 weeks. Using Cox proportional hazards models, the analysis specifically focused on the 6-week data to evaluate the relationship between early DLCO changes and OS and PFS, adjusting for ECOG, LIPI score, and PDL1 expression. Results: 47 patients had evaluable baseline and 6-week post-baseline DLCO measurements. The median baseline DLCO was 59%. 15 (32%) patients experienced a ≥15% reduction in DLCO at 6 weeks. Patients with DLCO decrease experienced lower OS (NR vs 12.5m; 1yr-OS 78.6% vs 53.8%; HR 3.7; p=0.011) and rPFS (7.7 vs 4m; HR 3.8; p=0.003) rates, in unadjusted and adjusted cox-regression models (Table 1 ). Conclusions: Significant reductions in DLCO early during ICI therapy are associated with poorer outcomes in aNSCLC patients. Monitoring DLCO changes could serve as an effective prognostic tool. Further research is needed to validate DLCO as a prognostic biomarker in clinical practice. Multivariable OS and rPFS model. Overall Survival rPFS Variable HR (95%CI); p-value HR (95%CI); p-value Baseline DLCO 1.04 (0.99-1.1);p=0.1 1.04 (1.01-1.08); p=0.011 DLCO ≥15% decrease 7.5 (1.7-33);p=0.009 7.6 (1.8-31.6); p=0.006 PLD1 (0, 1-50%, ≥50%) 0.17 (0.05-0.55); p=0.003 0.93 (0.47-1.86); p=0.8 ECOG 13.2 (1.9-50); p=0.01 1.35 (0.44-4.2); p=0.06 LIPI score 26 (4-55); p<0.001 1.6 (0.65-3.95); p=0.3