PDCD1 and colorectal carcinoma: As these advancements continue to evolve, a multi-faceted approach combining biomarker identification, TME modulation, immune engineering, and AI-driven precision medicine may ultimately enhance the effectiveness of PD-1/PD-L1 inhibitors in CRC, expanding their applicability beyond MSI-H/dMMR tumors and reshaping the future of immunotherapy with respect to this malignancy [162,163].