Immune Checkpoint Inhibitors in the Treatment of Gastrointestinal Malignancies: A Review of Current and Future Therapies

Gastrointestinal cancers are some of the most common malignancies worldwide. Traditional chemotherapy has been disappointing in improving overall survival in patients with unresectable or metastatic disease. The dawn of immunotherapy has led to emerging strategies in incorporating immune checkpoint inhibition either as single agents or in combination when treating gastrointestinal cancers. In this review, a general overview of the state of immunotherapy in the treatment gastrointestinal cancers is first provided. Subsequently, a review of the FDA-approved uses of immunotherapy in gastric, gastroesophageal, hepatobiliary, pancreatic and colorectal cancers will be provided followed by a glimpse into future treatment directions.