According to a study, GAS5 expression was statistically decreased by 29.94% in the plasma of stage I NSCLC patients, and the combined detection of CEA, CA199, and GAS5 performed well in the early diagnosis of NSCLC [108] In addition, circulating GAS5 was confirmed as a biomarker to evaluate and monitor NSCLC surgical resection, with an increasing trend seven days after surgery [42, 108] Tumor‐derived exosomal GAS5 is also a promising biomarker for NSCLC. Here, CEACAM5 is linked to neoplasm.