MSI arises from mutations or epigenetic alterations in the MMR proteins (MLH1, MSH2, MSH3, MSH6, PMS1, or PMS2).30 As anticipated, we found a correlation between MSI‐H and dMMR: 32.14% of Chinese patients with cancer showing MSI‐H exhibited dMMR, and those cancer patients were TMB‐H (Figure 6A). Here, MSH3 is linked to cancer.