PDCD1 and neoplasm: Various studies reported that the reinvigoration potential of T cell exhaustion via PD-1 inhibition implicates stronger anti-tumor immunity and better prognosis.29,36 PD-1 positive TAMs, which declined after such neoadjuvant, were also recently reported for inhibiting macrophages in the tumor microenvironment.37 Given to above results, we hypothesized that CRT might reverse the inhibitory immune microenvironment in MSS/pMMR patients, resulting in the encouraging therapeutic effects.