For several years, tumor protein biomarkers such as CEA, alpha-fetoprotein (AFP), and carbohydrate antigen 19–9 (CA19-9) have been extensively utilized in the screening and diagnosis of lung cancer, evaluation of treatment efficacy, postoperative monitoring, and prognostic assessment (Wojtalewicz et al., 2023; Bitter et al., 2023). The gene discussed is CEACAM5; the disease is lung cancer.