Immunotherapy using PD‐1/PD‐L1 blockade is now widely used for the treatment of many malignant tumours, but only a subset of patients respond to the therapy.39, 40, 61 The mechanism by which PD‐1/PD‐L1 regulates CD8+ T cells found in our study may resolve the problem of non‐responding patients and allow the combined treatment to achieve effective clinical effects in GIST as soon as possible. Here, PDCD1 is linked to cancer.