Abstract
DNA mismatch repair deficiency has been identified as a biomarker that strongly correlates with tumor response to anti-programmed cell death protein-1 (PD-1) checkpoint blockade therapy in the metastatic setting. In a promising Phase 2 study published in the New England Journal of Medicine, Cercek et al demonstrate that PD-1 checkpoint blockade also has potential in the neoadjuvant setting and may eliminate the need for surgical intervention. These results offer great hope to patients with a variety of solid malignancies because those who experience complete clinical responses may be able to safely choose non-operative management to preserve organ function and minimize side effects associated with surgery.