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.