CD274 and gastric cancer: In malignant tumors of the digestive system, PD-L1 expression was a marker of poor prognosis (HR = 1.44, 95% CI = 1.18–1.76, p < 0.001), including GC (HR = 1.43, 95% CI = 1.05–1.94, p = 0.021) and pancreatic cancer (HR = 2.64, 95% CI = 1.78–3.93, p < 0.001) [16].