Diagnostic value of thoracic CT combined with tumor markers in the elderly patients with early lung cancer

Abstract

Objectives To investigate the diagnostic value of thoracic CT combined with tumor markers of carcinoembryonic antigen(CEA), neuron-specific enolase(NSE), cyfra21-1, and squamous cell carcinoma-antigen(SCC-Ag)in the elderly patients with early lung cancer. Methods Two hundreds and twelve elderly subjects were divided into 3 groups: a lung cancer group(stageⅠa-Ⅲa, n=60)diagnosed by pathological findings of puncture-or postsurgical-tissue, a benign group(n=84)with pathology-diagnosed benign lesions and a normal control group(n=68)with normal health examination.The chest CT signs and levels of serum tumor markers of the 212 individuals were retrospectively analyzed. Results The serum levels of CEA, NSE, cyfra21-1, and SCC-Ag were higher in the lung cancer group than in the benign group and the normal group(P=0.0247, 0.0319, 019, 0.0384, respectively). The positive rate of tumor marker was increased along with the increased lung cancer diameter.The lung cancer diameter 3 cm of four groups showed that the positive rate[case(%)]of tumor marker was 1(16.7), 5(38.5), 11(64.7), 23(95.8), respectively, with a significantly difference in total 4 groups(χ2=81.09, P=0.00125)and between diameter 2-2.9 cm and >3 cm groups(χ2=6.810, P=0.00784). The sensitivity of chest CT in diagnosis of lung cancer was 85.0%, specificity 55.9%, positive predictive value 43.2%, and negative predictive value 90.4%.A higher sensitivity of chest CT combined with tumor markers in diagnosis of lung cancer was 95.0%, a higher specificity 86.8%, and a higher negative predictive value 97.8%. Conclusions The detection of chest CT combined with serum tumor markers is helpful to improve the accuracy of diagnosis in elderly patients with early lung cancer, especially when the diameter of tumor is >3 cm. Key words: Tumor markers, biological; Lung cancer; Early diagnosis