Survival of colorectal cancer patients based on mismatch repair gene mutation status

Background. According to the Global Cancer Observatory 2020, colorectal cancer was responsible for 19.3 million new cases and 10 million deaths worldwide. One of the main mechanisms underlying the pathogenesis of colorectal cancer involves the presence of mismatch repair (MMR) gene mutations. Guidelines recommend adjusting colorectal cancer treatment based on MMR gene mutation status. This approach combines targeted therapy with conventional chemotherapy regimens. Methods. The methodology focused on research from the past five years. Retrospective cohort studies were chosen due to their high level of evidence in prognostic research. A literature search was conducted using the keywords “Colorectal Cancer”, “Microsatellite Instability or Mismatch Repair”, “Gene Mutation”, and “Survival or Prognosis” in three electronic databases: PubMed, ScienceDirect, and Scopus. Results. Analysis revealed that colorectal cancer with deficient MMR (dMMR) status was associated with better survival outcomes compared to proficient MMR (pMMR) status in stage II and III colorectal cancer. Adjuvant chemotherapy showed greater efficacy for stage III colorectal cancer with dMMR status. Furthermore, combining adjuvant chemotherapy with targeted therapy significantly improved the survival of patients with dMMR status. However, stage IV colorectal cancer with dMMR/MSI did not show any prognostic advantage, despite a lower risk of distant metastasis. Conclusion. Colorectal cancer with pMMR status exhibited lower survival rates compared to those with dMMR status. Patients with stage II and III colorectal cancer and dMMR/MSI status benefited from neoadjuvant chemotherapy and targeted therapy, demonstrating improved disease-free survival compared to those with pMMR/MSS status.