Association of neutrophil percentage-to-albumin ratio with progression-free survival and overall survival in cancer patients treated with PD-1/PD-L1 inhibitors.

2574 Background: The Neutrophil Percentage-to-Albumin Ratio (NPAR) reflects systemic inflammation and nutritional status. Its prognostic and predictive value in cancer patients treated with PD-1/PD-L1 inhibitors remains unclear. We investigated the association of the baseline of NPAR with PFS and OS in cancer patients who received PD-1/PD-L1 inhibitors. Methods: A retrospective cohort of 532 patients treated with PD-1/PD-L1 inhibitors at the Second Xiangya Hospital of Central South University between 2018 and 2024 was enrolled. Participants were divided into tertiles based on the baseline of NPAR. PFS and OS were assessed using Kaplan–Meier method and log-rank tests. Univariable and multivariable Cox proportional hazards models were employed to examine the association between NPAR and survival outcomes, with sequential adjustment for clinically relevant confounders. Results: The median PFS and OS of total patients was 21.3 months (IQR, 10.5–32.7) and 24.7 months (IQR, 16.9–41.5), respectively. Individuals with elevated NPAR experienced significantly worse PFS and OS than those with low NPAR and medium NPAR (PFS: p < 0.05; OS: p < 0.0001). Subgroup analyses showed the consistent results in the lung cancer patients (PFS: p < 0.05; OS: p < 0.01). In univariate COX regression analyses, each one-unit increment in NPAR corresponded to hazard ratios (HRs) of 1.032 (95% CI, 1.004–1.062; p < 0.05) for PFS and 1.069 (95% CI, 1.035–1.104; p < 0.001) for OS. Multivariate Cox regression analysis identified that a high NPAR level remained independently associated with inferior survival outcomes after adjusting for confounders. Compared with the low NPAR group, the high NPAR group showed worse PFS (HR, 1.38; 95% CI, 1.03-1.84; p < 0.05) and OS (HR, 1.95; 95% CI, 1.36-2.79; p < 0.001) in the fully adjusted model (Model 4). Conclusions: Elevated NPAR can independently predict worse PFS and OS in cancer patients receiving PD-1/PD-L1 inhibitors and represents a simple, low-cost biomarker for clinical risk stratification. Association between NPAR and PFS/OS of cancer patients. Model 1HR (95%CI) p-value Model 2HR (95%CI) p-value Model 3HR (95%CI) p-value Model 4HR (95%CI) p-value NPAR PFS OS PFS OS PFS OS PFS OS PFS OS PFS OS PFS OS PFS OS Low group ref ref ref ref ref ref ref ref High group 1.40(1.06-1.85) 2.05(1.45-2.90) 0.018 <0.001 1.42(1.07-1.89) 1.98 (1.40-2.82) 0.015 <0.001 1.40 (1.05-1.87) 1.99 (1.40-2.83) 0.023 <0.001 1.38 (1.03-1.84) 1.95 (1.36-2.79) 0.032 <0.001 Model 1: unadjusted. Model 2: adjusted for sex, diabetes, hyperlipidemia, cardiovascular disease, cerebrovascular disease, pulmonary tuberculosis and viral hepatitis type B. Model 3: adjusted for model 2 + single ICIs, chemotherapy, radiotherapy. Model 4: adjusted for model 3 + NSAIDS, PPI, β-blocker, hormone, whiteboard-raising drugs, anticoagulant and antithrombotic drugs.