Performance Evaluation of Combined Detection of Serum CEA, CYFRA21-1, CA125, and NSE in Patients with Lung Cancer by Fluorescence Flow Cytometry

Objective: To investigate the effect of combined detection of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1), cancer antigen 125 (CA125), and neuron-specific enolase (NSE) in patients with lung cancer by fluorescence flow cytometry. Methods: From August 2019 to July 2022, 200 patients with lung cancer diagnosed by pathology in our hospital were retrospectively analyzed. 2 mL venous blood was collected in a fasting state and centrifuged to separate the serum (containing human chorionic gonadotropin antibody [anti-hCG antibody], hepatitis B surface antibody [anti-HBs antibody], and CEA). Results: The sensitivities of CEA and CYFRA21-1 detected via enzyme-linked immunosorbent assay (ELISA) were 100%, and the detection limits were 0.5 ng/mL and 0.1 ng/mL, respectively; the sensitivities of CA125 and NSE detected via flow cytometry were 100%, and the detection limits were 10 U/mL and 2 ng/mL, respectively. Compared with ELISA, the sensitivities of CA125 and NSE detected via flow cytometry were higher. When the concentration of CEA was 10–40 ng/mL, the sensitivities of the three markers CYFRA21-1, CA125, and NSE showed no significant changes (P > 0.05); when the concentration of CEA was 40–80 ng/mL, the sensitivity of CEA significantly decreased (P < 0.01), but the sensitivities of the three markers CYFRA21-1, CA125, and NSE showed no significant changes (P > 0.05); when the concentration of CEA was 80–200 ng/mL, the sensitivities of all four markers showed no significant changes (P > 0.05). Conclusion: Compared with the double-antibody sandwich ELISA, fluorescence flow cytometry has certain advantages, including high sensitivity, good precision, short detection time, low sample usage, and low medical cost; thus, it is worthy of clinical promotion.