Application and challenge of microsatellite instability detection in colorectal cancer / 中华消化外科杂志

ABSTRACT

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers. The incidence and mortality of CRC are still rising in China. It is of great importance to explore the molecular mechanisms of the development and progression of CRC. Microsatellites are short tandem repeats that are distributed throughout the genome. Detection of microsatellite instability (MSI) is of great value in the diagnosis and treatment of CRC. MSI detection is an important method for Lynch syndrome screening. For patients with stage Ⅱ CRC, MSI status is an influencing factor for post-operative recurrence and an important reference for adjuvant therapy. For patients with stage Ⅳ CRC, MSI status is an important indicator for screening potential patients suitable for treatment of immune checkpoint inhibitors. However, there are still problems concerning the application of MSI. The detection methods of MSI have not been fully unified. The requirement of MSI detection in CRC patients are universal but not precise. MSI is not a valid predictor for the prognosis of CRC patients, and it could not effectively predict the efficacy of chemotherapy and immunotherapy. Moreover, with the application of other molecular markers, such as programmed death-1, programmed death-ligand 1, tumor mutation burden and immunoscore, the value of MSI in CRC is being challenged and remains to be unveiled with more studies. The authors investigate the problems in MSI detection and application, in order to provide reference for clinical practice.