Carcinoembryonic Antigen, Squamous Cell Carcinoma Antigen, CYFRA 21-1, and Neuron-specific Enolase in Squamous Cell Lung Cancer Patients

Abstract

Abstract Background: Carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC-Ag), and CYFRA 21-1 are the most useful markers for non-small cell lung cancer (NSCLC), but neuron-specific enolase (NSE) is a tumor maker of choice for SCLC. The determination of NSE in NSCLC could allow selection of patients with neuroendocrine features. NSCLC patients whose tumors have neuroendocrine properties may be more responsive to chemotherapy; however, these tumors have been reported to be more aggressive. Tumor markers are not suitable for diagnosis; their principal applications are in monitoring of therapy and prognosis. Methods: Tumor markers were measured in 200 untreated patients with squamous cell lung cancer (SQC) and a reference group (n = 220; 124 healthy persons and 96 patients with nonmalignant lung disease). CEA and SCC-Ag were measured by microparticle enzyme immunoassays on Abbott AxSYM and IMx analyzers. CYFRA 21-1 and NSE were measured by electrochemiluminescence immunoassays on the Roche Elecsys 2010. Results: CEA, SCC-Ag, CYFRA 21-1, and NSE were increased above the cutoffs in 26%, 32%, 67%, and 28% of tested patients, respectively. The area under the ROC curve for CYFRA 21-1 was higher than those for CEA, SCC-Ag, and NSE (SQC vs controls). CYFRA 21-1 and CEA were significantly higher in advanced SQC than in early stages of disease (P <0.0001 and P <0.0004, respectively). In multivariate analysis of survival, CYFRA 21-1 was an independent but nonspecific prognostic factor in the operable group of SQC patients, whereas NSE was an independent prognostic factor in the advanced stages of disease. Conclusion: CYFRA 21-1 is an independent prognostic factor in earlier stages and NSE in the advanced stages of SQC.