Transforming the landscape of colorectal cancer treatment with immunotherapy: Evolution and future horizons

Colorectal cancer (CRC) continues to be one of the most prevalent and lethal cancers worldwide. Over the past decades, immune checkpoint inhibitors (ICIs) have shown to significantly improve patient outcomes in mismatch repair-deficient metastasized CRC. However, widening the scope of this novel treatment modality has been the object of growing interest. This article will review several landmark trials, while exploring various aspects of this rapidly evolving field, including potential neoadjuvant (or even entirely nonsurgical) and adjuvant indications in localized disease. We will also discuss differences between management of rectal and colon cancer, current and expected challenges (eg. resistance, toxicities, pseudoprogression, biomarkers) and other future opportunities including combinations with other therapeutic agents and the role of ICIs in the treatment of both deficient as well as proficient mismatch repair (dMMR and pMMR respectively) CRC.