PDCD1 and cancer: Gastric cancer (GC) remains the fifth most prevalent malignancy and the third leading cause of cancer‐related deaths worldwide.[1, 2, 3] Considering its vague initial signs, 70–90% of patients have progressed to advanced stages at initial diagnosis, leading to an unfavorable overall prognosis.[4] Immune checkpoint blockade (ICB) against programmed cell death 1 (PD‐1) and its ligand programmed cell death ligand 1 (PD‐L1) presents an opportunity to treat advanced GC.