PD-1/PD-L1 based immunochemotherapy versus chemotherapy alone for advanced esophageal squamous cell carcinoma: A meta-analysis focus on PD-L1 expression level.BACKGROUND
 We aimed to study the clinical efficacy and toxicity of immunochemotherapy based on PD-1/PD-L1 compared with chemotherapy alone in the treatment of advanced ESCC, focusing on analyzing the influence of PD-L1 expression level.


 Five randomized controlled trials comparing PD-1/PD-L1 based immunochemotherapy with chemotherapy alone for advanced ESCC were included.  PD-1/PD-L1 based immunochemotherapy significantly could improve survival outcomes in patients with advanced ESCC. 
PD-1
PD-1/PD-L1 based immunochemotherapy versus chemotherapy alone for advanced esophageal squamous cell carcinoma: A meta-analysis focus on PD-L1 expression level.BACKGROUND
 We aimed to study the clinical efficacy and toxicity of immunochemotherapy based on PD-1/PD-L1 compared with chemotherapy alone in the treatment of advanced ESCC, focusing on analyzing the influence of PD-L1 expression level.


 Five randomized controlled trials comparing PD-1/PD-L1 based immunochemotherapy with chemotherapy alone for advanced ESCC were included.  Even with PD-L1 tumor proportion score <1%, immunochemotherapy also showed a significant survival advantage (OS: HR = 0.65, 95% CI 0.46-0.93; PFS: HR = 0.56, 95% CI 0.46-0.69, respectively).  However, for PD-L1 combined positive score (CPS) < 1, the survival advantage of immunochemotherapy was not significant (OS: HR = 0.89, 95% CI 0.42-1.90; PFS: HR = 0.71, 95% CI 0.47-1.08, respectively).  PD-1/PD-L1 based immunochemotherapy significantly could improve survival outcomes in patients with advanced ESCC. 
PD-L1
PD-1/PD-L1 based immunochemotherapy versus chemotherapy alone for advanced esophageal squamous cell carcinoma: A meta-analysis focus on PD-L1 expression level.BACKGROUND

Meta-analysis