The baseline preoperative serum CK19-2G2 level in lung cancer patients was significantly higher than that of benign disease patients (8.92±9.95 vs. 0.71±0.78 mU/mL; P<0.001) and that of the healthy control group (8.92±9.95 vs. 0.26±0.19 mU/mL; P<0.001) (Table 2, and the full data is shown in Table S1). Here, KRT19 is linked to lung cancer.