A novel therapy based on programmed death 1 (PD-1) inhibitors has been proved to be effective in advanced esophageal cancer. This article is a meta-analysis that aims to compare the efficacy and safety of anti-PD-1 therapy with chemotherapy in esophageal cancer.
Data were collected from eligible studies searched from PubMed, Web of Science, Cochrane Library, and Embase. Pooled hazard ratio (HR) for overall survival (OS), progression-free survival (PFS), and objective response rate (ORR) was estimated to assess the efficacy of PD-1 inhibitors versus chemotherapy. The subgroup analysis was also performed to evaluate the OS benefits. The OR for the occurrence of treatment-related adverse effects was calculated to assess the safety of anti-PD-1 therapy.
A total of 4 studies were analyzed. Compared with patients with chemotherapy, patients with anti-PD-1 therapy had a significant improvement in OS (HR = 0.79, 95% CI: 0.71-0.88, and P<0.001), but no significant relationship was observed in PFS (HR = 0.96, 95% CI: 0.76-1.20, and P = 0.69) and ORR (OR = 1.92, 95% CI: 0.98-3.72, and P = 0.06). A similar result was observed in esophageal squamous cell carcinoma. The significant predictor for treatment benefit alone was histology (P = 0.009). The incidence of grade 3 – 5 treatment-related adverse effects in anti-PD-1 therapy was distinctly lower than that in chemotherapy, but there is no statistical difference in all treatment-related adverse effects.
Anti-PD-1 therapy significantly prolonged the OS, simultaneously lowered grade 3 – 5 treatment-related adverse effects versus chemotherapy.

Copyright © 2021. Published by Elsevier Inc.

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