P3.03-047 Diagnostic Value of Secretary Leukocyte Peptide Inhibitor (SLPI) in Pleural Fluid in Malignant Pleural Mesothelioma: Topic: Mesothelioma Clinical

There is no established diagnostic marker for malignant pleural mesothelioma (MPM). The aim of this study was to evaluate the usefulness of secretary leukocyte peptide inhibitor (SLPI) in pleural fluid for the diagnosis of MPM. The study included 52 MPM patients, 69 patients of lung cancer with pleural effusion (LC), and 50 patients with benign asbestos pleural effusion (BAPE) that were included as a control group. Pleural fluid was collected from these patients and SLPI was determined using Quantikine ELISA Human SLPI (R＆D Systems). Pleural fluid hyaluronic acid (HA) and soluble mesothelin related peptide (SMRP) were also determined as comparison. Median values of pleural fluid SLPI in MPM, LC, and BAPE were 108.1 ng/ml, 87.4 ng/ml, and 48.6 ng/ml, respectively. SLPI value in patients with MPM were significantly higher than those in other groups (P=0.000). SLPI value was higher in epithelioid subtype of MPM than in other subtypes. Median values of pleural fluid HA in MPM, LC, and BAPE were 86950 ng/ml, 20700 ng/ml, and 31500 ng/ml, respectively. Median values of pleural fluid SMRP in MPM, LC, and BAPE were 15.38 ng/ml, 5.70 ng/ml, and 7.31 ng/ml, respectively. Pleural fluid HA and SMRP in MPM were also significantly higher than in other groups (P=0.000). Receiver operating characteristics analysis was performed to examine the usefulness of these 3 markers for the differentiation of MPM and BAPE, and demonstrated that area under the curve values were 0.823 for SLPI, 0.760 for HA, and 0.743 for SMRP. Pleural fluid SLPI is a useful biomarker for differential diagnosis of MPM.