Targeting Immune Checkpoints in Esophageal Cancer: A High Mutational Load Tumor

Checkpoint inhibitors (eg, programmed cell death protein 1 [PD-1], programmed cell death ligand 1 [PD-L1], cytotoxic T-lymphocyte associated protein 4 [CTLA-4] antibodies) are changing how we understand cancer and provide a means to develop modern immunotherapies. An emergent notion relates success with checkpoint inhibitors with high mutational load tumors. There are few studies that examine checkpoint protein expression and relate these to clinical outcomes after the conventional treatment of patients with esophageal cancer, which has a high mutational load. The objective of this review is to summarize the literature that examines checkpoint expression and clinical outcomes, as well as propose an accelerated approach to introducing these therapies into the clinic to treat patients with esophageal cancer. (C) 2017 by The Society of Thoracic Surgeons