Objective: To investigate the clinical significance of a combination of several serum tumor markers in the diagnosis of lung cancer.
Methods: Serum CEA, CA125, CA199, CYFRA21-1 and NSE were measured with RIA, chromatometrychemoluminescence, ELISA and biochemoluminescence methods respectively in 340 patients with lung cancers at different TNM stages, 120 patients with benign lung diseases, and 45 healthy people. The sensitivities, specificities and accuracies of different combination of those markers for the diagnosis of lung cancers were compared.
Results: CYFRA21-1 had the highest sensitivity and accuracy (60.0% and 70.3%) and CA199 had the highest specificity (99.4%) for detecting lung cancers. CYFRA21-1 had the highest sensitivity (79.6%) for detecting squamous carcinoma. CEA had the highest sensitivity of (75.7%) for detecting adenocarcinoma. NSE had the highest sensitivity (76.2%) for detecting small cell lung cancers (SCLC). The combination of several serum tumor markers had higher sensitivities than the single marker for the diagnosis of lung cancers. With two markers, the combination of CYFRA21-1 and NSE had the highest sensitivity and accuracy (82.9% and 83.4%), while the combination of CA125 and CA199 had the highest specificity (94.5%). With three markers, the combination of CEA, NSE and CYFRA21-1 had the highest sensitivity and accuracy (89.1% and 85.1%), while the combination of CEA, CA125 and CA199 had the highest specificity (86.7%). The combination of CEA, CA125, CA199, CYFRA21-1 and NSE produced the best value, with a sensitivity of 93.8%, a specificity of 71.5%, and an accuracy of 86.5%.
Conclusion: Serum CEA, CA125, CA199, CYFRA21-1 and NSE are helpful markers for the diagnosis of lung cancer. The combination of the markers can improve the sensitivity and accuracy of the diagnosis.