CD274 and gastrointestinal stromal tumor: However, interestingly, the PD‐L1 expression in tumours with different mutations, rupture statuses or sites was similar (data not shown), which was similar to the results of another study.33 While following 112 GIST patients for nearly 1‐5 years, tumour recurrence was observed in 21 patients, including 12 patients not treated with adjuvant imatinib and nine patients treated with adjuvant imatinib.