In seven studies investigating 692 thymoma patients, the pooled PD-L1-positive ratio is 42% (95% CI [0.28; 0.59], random effect model), and the rate in the TC group including 339 patients from ten studies is 41% (95% CI [0.31; 0.52], random effect model) (Figure 11C). Here, CD274 is linked to thymoma.