Integration of peripheral blood biomarkers with computed tomography to differentiate benign from malignant pulmonary opacities

Our purpose was to determine whether peripheral blood biomarkers MUC1 and C K19 could be used to complement imaging studies in differentiating benign f rom malignant indeterminate pulmonary nodules or masses detected on compute d tomography CT. One hundred and eighteen patients had a thoracic CT and bl ood drawn for tumor marker reverse transcriptase-polymerase chain reaction analysis. Thirty-five of the 118 patients had an indeterminate pulmonary no dular opacity on CT, and the findings then were correlated with the reverse transcriptase-polymerase chain reaction results. The sensitivity and speci ficity for the markers in determining malignancy was calculated. Thirteen o f the 35 opacities on CT proved to be benign, and 22 proved to be lung canc er. Among the patients with indeterminate pulmonary abnormalities. polymorp hic epithelial mucin protein 1 had a sensitivity and specificity for lung c ancer of 100% and 46%, respectively. Cytokeratin 19 had a sensitivity and s pecificity for lung cancer of 95% and 8%. respectively. These preliminary d ata showed that serum biomarkers polymorphic epithelial mucin protein 1 and cytokeratin 19 were not specific for lung cancer, although patients with a n indeterminate pulmonary abnormality and negative markers were unlikely to have lung cancer. Integration of imaging studies with the appropriate biom arkers may prove useful in evaluating indeterminate pulmonary nodules or ma sses.