Diagnostic value of CYFRA 21-1 tumor marker and CEA in pleural effusion due to mesothelioma.

Study objective The aim of our study was to assess the clinical value of CYFRA 21––1 tumor marker and carcinoembryonic antigen (CEA) as diagnostic tools that are complementary to cytology in the diagnosis of malignant mesotheliomas. Patients We measured CEA and CYFRA 21––1 in the pleural effusions (PEs) and serum of 106 patients (benign lung disease, 34 patients; bronchogenic and metastatic carcinoma, 40 patients; mesothelioma, 32 patients). Methods CEA and CYFRA 21––1 levels were determined by means of two commercial enzyme immunoassays. Results The cutoff levels of CYFRA 21––1 and CEA in malignant PEs, selected on the basis of the best diagnostic efficacy, were 41.9 ng/mL and 5.0 ng/mL, respectively. In all neoplastic PEs, CYFRA 21––1 and CEA sensitivity was 78% and 30.6%, respectively, with a specificity of 80% and 91%, respectively. The sensitivity of CYFRA 21––1 and CEA in patients with mesothelioma was 87.5% and 3.1%, respectively. The results of the CYFRA 21––1 assay were positive in 17 of 19 cases of mesothelioma (89.5%) with a negative or uncertain cytology. The association of the tumor marker assay and the cytology allowed a correct diagnosis in 30 of 32 cases of mesothelioma (93.7%). Conclusion This study suggests that CYFRA 21––1 would provide a useful parameter for the differential diagnosis between benign and malignant PE from mesothelioma when the result of cytology is negative or uncertain and the clinical context does not allow a more aggressive approach. Moreover, the association of CYFRA 21––1 with CEA could provide details for a differential diagnosis between mesotheliomas and carcinomas. In fact, an elevated CYFRA 21––1 level with a low CEA level is highly suggestive of mesothelioma, whereas high levels of CEA alone or high levels of both the markers suggest a diagnosis of malignant PE, excluding mesothelioma.