CEACAM5 and lung cancer: Furthermore, considering tumor markers such as carcino‐embryonic antigen (CEA), neuron‐specific enolase (NSE), and cytokeratin (CYF21‐1) are widely used to evaluate the diagnosis, progression, and prognosis of lung cancer patients,16 these three tumor markers combined with specific microorganisms were utilized to establish the clinical prediction models for lung cancer and then evaluate the performance to improve the clinical diagnosis of lung cancer.