For early-stage NSCLC (stage I and II), exosomal RP5-977B1 was superior in distinguishing patients from controls (for stage I and II patients, AUC = 0.8658, P < 0.001), while serum CEA and CYFRA21-1 revealed an AUC = 0.7011 (P = 0.0003) and 0.5792 (P = 0.5792), respectively (Fig. 3B, Tables 1, 2). This evidence concerns the gene CEACAM5 and non-small cell lung carcinoma.