Immune checkpoint inhibitors: a new era for esophageal cancer.

Introduction: The poor prognosis for patients with esophageal cancer (EC) requires evolving current treatment regimens. Immune checkpoint inhibitors show clinical efficacy and a great safety profile in multiple tumors. And the monoclonal antibodies that target programmed death receptor-1/programmed death receptor ligand-1 or the cytotoxic T lymphocyte antigen-4 pathway has shown potential curable effect of EC. Areas covered: This review article covers the prognostic significance of immune checkpoint expression, the accumulating current clinical studies of checkpoint inhibitors in esophageal cancer patients, and future directions. Expert opinion: Many clinical studies have reported favorable survival results with manageable toxicity of anti-programmed death receptor-1/programmed death receptor ligand-1 and anti-cytotoxic T lymphocyte antigen-4 treatment. More results are expected from future clinical studies. It is believed that combining chemoradiotherapy and immune checkpoint inhibitors can induce safe and efficient anti-tumor immune responses and can be a promising therapeutic strategy.