Alterations such as TP53 and APC, less common in MSI-high cases, relied on MSS-like morphology (e.g., gland-forming conventional adenocarcinoma with dirty necrosis40; Fig. S18–S20), while MSI-associated alterations (e.g., BRAF, RNF43, hypermutation) depended on MSI-related features, including medullary patterns, mucinous differentiation (with signet-ring cells; Fig. S23B), and high TILs40 (Fig. 6C–D, Fig. S12–S15, Fig. S21, Tab. Here, TP53 is linked to adenocarcinoma.