Combination of Circulating Tumor Cells with Serum Carcinoembryonic Antigen Enhances Clinical Prediction of Non-Small Cell Lung Cancer

Circulating tumor cells (CTCs) have emerged as a potential biomarker in the diagnosis, prognosis, treatment, and surveillance of lung cancer. However, CTC detection is not only costly, but its sensitivity is also low, thus limiting its usage and the collection of robust data regarding the significance of CTCs in lung cancer. We aimed to seek clinical variables that enhance the prediction of CTCs in patients with non-small cell lung cancer (NSCLC). Clinical samples and pathological data were collected from 169 NSCLC patients. CTCs were detected by CellSearch and tumor markers were detected using the Luminex xMAP assay. Univariate analyses revealed that histology, tumor stage, tumor size, invasiveness, tumor grade and carcinoembryonic antigen (CEA) were associated with the presence of CTCs. However, the level of CTCs was not associated with the degree of nodal involvement (N) or tumor prognostic markers Ki-67, CA125, CA199, Cyfra21-1, and SCCA. Using logistic regression analysis, we found that the combination of CTCs with tumor marker CEA has a better disease prediction. Advanced stage NSCLC patients with elevated CEA had higher numbers of CTCs. These data suggest a useful prediction model by combining CTCs with serum CEA in NSCLC patients.