Checkpoint inhibitors in gastrointestinal cancers: Expectations and reality

Immune checkpoint inhibitors represent revolutionary anti-cancer agents, being rapidly approved in different malignancies and settings. Gastrointestinal (GI) cancers represent a wide variety of tumors with specific characteristics and different responses to various therapeutic alternatives; while some are chemo-sensitive others are chemo-resistant and only respond to more aggressive cytotoxic regimens, targeted therapies or a combination of both. Preliminary results of immune checkpoint inhibitors in some GI cancers are promising, namely in hepatocellular carcinoma, anal cancers and microsatellite instability high colorectal cancers. An impressive instead of a impressive number of immune checkpoint inhibitors are being evaluated in different indications in GI cancers as single agents or in combination with other agents. We reported in this paper ongoing and published trials evaluating immune checkpoint inhibitors in hepatocellular carcinoma and biliary tract cancers, esophageal, gastric, pancreatic, colorectal and anal cancers and we discussed the future perspectives of these agents in GI cancers.