To develop AIMMeR (AI-based method to detect MMRd), we first performed immunostaining for MMR proteins MLH1, MSH2, MSH6, and PMS2 on tumor tissue microarrays (TMAs) from the SCOT trial, which compared 6 vs. 3 months of adjuvant oxaliplatin-based chemotherapy in stage III and high-risk stage II CRC across >100 recruiting sites37 (study CONSORT diagram provided as Figure 1). Here, MSH2 is linked to colorectal carcinoma.