Novel Treatment Options in Metastatic Esophageal Carcinoma: Checkpoint Inhibitors in Combination Therapies.

Background: Metastatic esophageal carcinoma (EC) has a poor prognosis and only limited treatment options. While immune checkpoint inhibitors (ICIs) have improved the treatment of a broad spectrum of cancers, patients with EC mostly fail to respond to this treatment. For that reason, it is crucial to understand the immune phenotype of each cancer patient and moreover, to understand how different therapies modulate the cancer microenvironment and sensitize the tumors to the treatment with ICIs.