Neoadjuvant immunotherapy for locally advanced/metastatic mismatch repair deficient colorectal cancer: a two-year institutional experience.

Loss of MMR functioning, termed MMR deficiency (MMRd), leads to microsatellite instability (MSI),² a hypermutated phenotype, and increased cancer susceptibility. Lynch syndrome patients are at an increased risk for a number of different malignancies, but most commonly develop colorectal and endometrial cancer.

Findings add to the growing body of evidence in support of neoadjuvant immune checkpoint inhibitors for MMRd CRC, and highlight the importance of screening all CRC for MSI-H/ MMRd.