Immuno-oncology for esophageal cancer.

Esophageal cancer (EC) is the seventh most common cancer, with a poor prognosis for metastatic EC patients and limited effective drugs for treatment. Nivolumab and pembrolizumab, monoclonal antibodies that inhibit interactions of PD-1 and its ligand (PD-L1), which induce lymphocyte activation, have antitumor activity. The ATTRACTION-3 trial compared nivolumab with taxane after first-line chemotherapy and demonstrated superior overall survival (OS) for esophageal squamous cell carcinoma. The KEYNOTE-181 trial that compared pembrolizumab with chemotherapy demonstrated superior OS for EC with a PD-L1 combined positive score ≥10. Trials to evaluate efficacy of combined cytotoxic agents and immune checkpoint inhibitors (ICI) as first-line chemotherapies, ICI-containing chemoradiotherapy, and pre/postoperative chemotherapy are ongoing and might provide important data to improve clinical outcomes.