CD274 and gastrointestinal stromal tumor: Notably, the PD‐L1 expression on GIST tumour cells within different risk classifications was variable, and a distinct population of high‐risk and resistant GIST patients had very high PD‐L1 expression, suggesting that PD‐1/PD‐L1 blockade might particularly benefit a subset of patients who urgently need to receive post‐operative treatment.