We first evaluated the expression level of cGAS-STING in tumor cells in pMMR CRC (n = 243) by assessing the IHC signal (ranging from 0 to 9), which was determined by multiplying the extent score (ranging from 0 to 3: 0 for no staining signal at all, 1 for <10%, 2 for 10–50%, and 3 for >50% of tumor cells stained) and the intensity score (0–3+: 0—none, 1+—weak, 2+—moderate, or 3+—strong). Here, STING1 is linked to neoplasm.