Figure 2

ROC curve of the SPP1 values in pleural effusion. SPP1 in PF from all 109 patients are 24 suffered from benign lung disease and 85 with NSCLC. The cut-off value was calculated to be 1247.90 ng/ml (sensitivity, 40.3%; specificity, 95.8%; area under the curve (AUC), 0.660; 95% confidence interval (CI): 0.550-0 .770). Based on cut-off value the positive predictive value is 97.1%; negative predictive value is 31.1%.