PD-L1 expression and its association with clinicopathological and computed tomography features in surgically resected non-small cell lung cancer: a retrospective cohort study.

Although some studies have assessed the correlation between clinicopathological features and programmed death-ligand 1 (PD-L1) in patients with non-smallcell lung cancer (NSCLC), few studies have focused on computed tomography (CT) signs. The results of some previous studies are inconsistent and contradictory. Therefore, this study aimed to analyze the clinicopathological and CT features of NSCLC patients with different PD-L1 expression levels. This retrospective analysis included 911 NSCLC patients who undergone pulmonary resection, and most of them were early-stage. PD-L1 expression was assessed by immunohistochemistry with the Dako PD-L1 22C3 pharmDx kit. Clinicopathological features and CT signs were investigated according to different PD-L1 expression levels. The prevalence of PD-L1 expression in the resected NSCLC patients was 46.9% (427/911), with 381 patients low expression (41.8%) and 46 patients high expression (5%). Male sex, current smoking status, higher positron emission tomography-computed tomography (PET-CT) SUVmax, and elevated serum carcinoembryonic antigen levels were more frequently observed in patients with high PD-L1 expression. The frequencies of squamous cell carcinoma type, spread through air space (STAS), TP53 mutations, advanced pathological stages, and micropapillary/solid subtype were significantly higher in patients with PD-L1 positive tumors (TPS ≥ 1%) than in those with PD-L1 negative tumors (TPS < 1%). ALK rearrangement was higher in patients with low-expression, and PD-L1-positive patients had bigger tumor diameter. The proportion of solid nodules and consolidation to tumor were higher in high-expression than those in the low- or negative expression PD-L1 patients. Regarding structural characteristic features, there were no differences in the frequency of irregular borders, pleural retraction, air bronchograms, bubble-like lucency or cavities, and vascular convergence among the three groups. The frequency of lobulated margins and spiculation was significantly higher in patients with PD-L1 positive tumors than in those with PD-L1 negative tumors. Patients with PD-L1 expression in NSCLC often exhibit certain clinicopathological characteristics. CT features may not reliably correlate with PD-L1 expression across different stages of lung cancer. Immunohistochemistry (IHC), using relevant kits, remains essential for further evaluation of PD-L1 expression levels.