Challenges of neoadjuvant immunotherapy in mismatch repair-deficient/microsatellite-unstable localized colon cancer patients

Despite cumulative evidence on the efficacy and tolerability of neoadjuvant immunotherapy in mismatch repair-deficient (dMMR) colon cancer (CC), it is still hard to draw clear recommendations on its indication in our daily clinical practice. Key clinical trials investigating neoadjuvant or adjuvant immune checkpoint inhibitors (ICIs) in dMMR non-metastatic CC were reviewed. Based on their results, we designed an algorithm in the management of dMMR CC patients. The decision to treat patients with non-metastatic dMMR CC with neoadjuvant or adjuvant ICIs is primarily based on the patient's clinical status, baseline computed tomography (CT) characteristics of the primary tumor, and the therapeutic objectives.