Predictive value analysis of CEA, CA125 and CYFRA21‑1 levels in evaluating the efficacy of tislelizumab combined with gemcitabine‑cisplatin chemotherapy in patients with advanced non‑small cell lung cancer

While chemoimmunotherapy is the standard for advanced non-small cell lung cancer (NSCLC), effective and accessible tools for monitoring early treatment response are needed. The present study evaluated the clinical efficacy and safety of tislelizumab + gemcitabine-cisplatin (GP) chemotherapy vs. GP alone in NSCLC, and assessed serum CEA, CA125 and cytokeratin 19 fragment (CYFRA21-1) levels for treatment monitoring. In total, 90 patients with advanced NSCLC (from January 2021 to December 2024) were randomized in a 1:1 manner to receive tislelizumab + GP (n=45) or GP chemotherapy alone (n=45). Outcomes included short-term response [objective response rate (ORR) and disease control rate (DCR)], long-term progression-free survival (PFS) and overall survival (OS) (data cut-off, May 31, 2025; median follow-up, 23.5 months), 3-month biomarker changes and adverse events (AEs). The tislelizumab + GP group demonstrated numerically higher ORR/DCR (P>0.05), significantly longer median PFS (20.8 vs. 10.0 months, P=0.03) and a trend toward improved OS (not reached vs. 16.0 months; P=0.095). Post-treatment biomarker levels were significantly decreased in the study group (P<0.05) with comparable AEs. Receiver operating characteristic curves analyzed the diagnostic value of the combined biomarker panel compared with each biomarker individually for the prediction of short-term efficacy, which demonstrated significantly enhanced performance for the combination (P<0.05). In conclusion, combined CEA, CA125 and CYFRA21-1 effectively evaluated short-term efficacy. Furthermore, tislelizumab + GP demonstrated favorable safety and improved survival outcomes (particularly PFS) within follow-up.