CD274 and adenocarcinoma: Analyzing clinical data, GC use showed no significant link to age, gender, smoking, ECOG status, TNM stage, PD-L1 levels, brain metastases presence, or treatment lines (p > 0.05), and was significantly associated with histological type (p = 0.019; Table 1), possibly due to the high percentage of patients pretreated with pemetrexed chemotherapy in adenocarcinoma.