While innate immune system, including NK cells, dendritic cells, macrophages, and tumor-specific T cells, play pivotal roles in eliminating residual tumor cells, persistent MRD may disrupt immune surveillance by depleting CD8+ T cells and upregulating the immunosuppressive programmed cell death-ligand 1 (PD-L1), thereby promoting immune evasion and recurrence [24,25,26]. Here, CD8A is linked to neoplasm.