PD-1 inhibitors versus chemotherapy as second-line treatment for advanced esophageal squamous cell carcinoma: a meta-analysis

• Published in: BMC cancer Vol. 21; no. 1; p. 1195
• Main Authors: Zhu, Xinxin, Shanzhou, Qiyue, Li, Danyang, Pang, Xuezhou, Ma, Daiyuan
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 10.11.2021; BioMed Central; BMC
• Subjects: Adverse events; Antineoplastic Combined Chemotherapy Protocols - administration & dosage; Antineoplastic Combined Chemotherapy Protocols - adverse effects; Apoptosis; B7-H1 Antigen - analysis; B7-H1 Antigen - metabolism; Bias; Cancer; Cancer therapies; Cell death; Chemotherapy; Clinical trials; Comparative analysis; Disease control; Drug therapy; Efficacy; Esophageal cancer; Esophageal Neoplasms - diagnosis; Esophageal Neoplasms - drug therapy; Esophageal Neoplasms - mortality; Esophageal squamous cell carcinoma; Esophageal Squamous Cell Carcinoma - diagnosis; Esophageal Squamous Cell Carcinoma - drug therapy; Esophageal Squamous Cell Carcinoma - mortality; Esophagus; Humans; Immune Checkpoint Inhibitors - administration & dosage; Immune Checkpoint Inhibitors - adverse effects; Immunotherapy; Meta-analysis; Metastasis; Methods; Monoclonal antibodies; Neoplasm Staging; Oncology; Patient outcomes; Patients; PD-1; PD-1 protein; PD-L1 protein; Programmed Cell Death 1 Receptor - antagonists & inhibitors; Programmed Cell Death 1 Receptor - metabolism; Progression-Free Survival; Randomized Controlled Trials as Topic; Safety; Squamous cell carcinoma; Tumors; China; meta-analysis; Efficacy; Esophageal squamous cell carcinoma; Chemotherapy; Safety; PD-1
• ISSN: 1471-2407; 1471-2407
• DOI: 10.1186/s12885-021-08958-3

Aim to establish the inhibitors of programmed cell death protein 1 (PD-1) as second-line therapy for advanced esophageal squamous cell carcinoma (ESCC). Published clinical trials in the PubMed, Medline, Embase databases on PD-1 inhibitors for the treatment of ESCC were searched, along with an additional search on abstracts from the American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) from inception to September 2021. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (TRAEs) were synthesized using STATA. A total of 1970 patients (PD-1 inhibitors: 987; chemotherapy: 983) were enrolled in five randomized controlled trials. Compared with conventional chemotherapy, second-line PD-1 inhibitors significantly improved the OS (hazard ratio [HR] = 0.73, 95% confidence interval [CI]: 0.66-0.81; P < 0.001) and ORR (relative risk [RR] = 1.89, 95% CI: 1.16-3.05; P = 0.01) of advanced ESCC patients, especially significantly prolonged the OS in the patients with positive programmed death-ligand 1 (PD-L1) status (HR = 0.64, 95% CI: 0.53-0.77; P < 0.001); but did not better PFS (HR = 0.88, 95% CI: 0.68-1.14; P = 0.330) and DCR (RR = 0.89, 95% CI: 0.59-1.37; P = 0.603). Moreover, PD-1 inhibitors were associated with statistically lower incidences of grade 3-5 TRAEs. Second line PD-1 inhibitors significantly improved the OS and ORR of patients with advanced ESCC, especially the OS of those with positive PD-L1 expression, and did not result in significant improvement in PFS and DCR. Compared to chemotherapy, second-line PD-1 inhibitors had superior safety profiles for the treatment of advanced ESCC.