Prognostic significance of PD-L1 in advanced non-small cell lung carcinoma

This study aimed to investigate the prognostic value of PD-L1 in Chinese patients with non-small cell lung carcinoma (NSCLC). In this retrospective study, 97 patients with NSCLC were consecutively recruited. The expression profiling of PD-1, PD-L1, p53 and Ki-67 was detected by immunohistochemistry. Median survival time was estimated by Kaplan–Meier survival curve with log-rank test. Risk factors were evaluated by Cox Proportional Hazards regression models. The median tumor size was larger (3.5 cm) among patients with positive PD-L1 expression, compared to those with negative expression (2.0 cm; P < .01). Compared to those with negative PD-L1 expression, patients with positive PD-L1 expression had significantly higher rates of nerve invasion (26.3% vs 5.0%; P < .01), blood vessel invasion (47.4% vs 20.0%; P < .01) and lymph node metastasis (64.9% vs 27.5%; P < .01), more advanced tumor stage (P < .01) and Ki-67 index (P < .01). PD-L1 expression status was not significantly associated with disease-free (DFS) or overall survival (OS). However, for patients with advanced disease, PD-L1 positive expression was related to worse outcome (HR: 4.13; 95% CI: 1.06–16.12). Positive PD-L1 expression is associated with more aggressive pathological features and poorer prognosis in advanced stage NSCLC.