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

## TL;DR

This paper discusses the challenges and considerations of using immunotherapy before surgery in colon cancer patients with mismatch repair deficiency.

## Contribution

The paper proposes a tailored decision-making algorithm for using immunotherapy in dMMR colon cancer patients.

## Key findings

- Neoadjuvant immunotherapy is effective and well-tolerated in dMMR colon cancer.
- Treatment decisions should consider patient status, tumor CT characteristics, and treatment goals.
- Clear clinical guidelines for neoadjuvant immunotherapy in dMMR colon cancer remain elusive.

## Abstract

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.

•ICIs as neoadjuvant treatment in patients with localized dMMR CC is challenging.•Neoadjuvant ICIs are efficient and well tolerated in CC.•The decision of neoadjuvant ICIs should be tailored to the patient’s condition, the primary tumor CT scan characteristics and the objectives of treatment.

ICIs as neoadjuvant treatment in patients with localized dMMR CC is challenging.

Neoadjuvant ICIs are efficient and well tolerated in CC.

The decision of neoadjuvant ICIs should be tailored to the patient’s condition, the primary tumor CT scan characteristics and the objectives of treatment.