Abstract
PURPOSE: The expression of PD-L1 is linked to lung cancer severity; however, its prognostic value after resection is unclear. In this study, we investigated its role in resected lung cancers. METHODS: We analyzed 658 patients with stage pIA-IIIA NSCLC who underwent complete resection. We assessed the PD-L1 expression by stage and its link to cancer severity, focusing further on its prognostic impact in resected stage I cell lung cancer. RESULTS: The high expression of PD-L1 increased with disease progression (13.0% in IA to 36.2% in III). In stage I non-small cell lung cancer, elevated PD-L1 expression levels were more common in patients with serum CEA levels ≥ 5 (26.0%), SUVmax ≥ 5 (26.7%), and squamous cell carcinoma (41.5%). PD-L1-negative patients showed a better prognosis than PD-L1-positive patients, even with the use of immune checkpoint inhibitors following relapse (5-year OS: 94.3% vs. 83.2%, p < 0.01). CONCLUSION: The expression of PD-L1 in lung cancer appears to be associated with oncological severity and may influence the prognosis of early-stage disease. Additionally, in early-stage lung cancer, immune checkpoint inhibitors may not fully compensate for the negative prognostic impact of the high expression of PD-L1.