PDCD1 and colorectal carcinoma: Recently, a clinical trial showed that 12 CRC patients with mismatch repair (MMR)‐deficiency exhibited high sensitivity to single‐agent programmed cell death protein 1 (PD‐1) blockers and achieved 100% clinical complete response.[2] However, only 5% to 10% of patients were MMR‐deficient.[3] A large proportion of CRC patients are MMR proficient, and 30% to 60% of these patients are resistant to neoadjuvant chemotherapy (NAC).[4] Despite advancements in novel therapeutic approaches, they are not substantially effective in reducing distant recurrence or improving overall survival.