Diagnostic value of pleural effusion Krebs von den Lungen-6 in malignant pleural effusion of patients with non–small cell lung cancer

Abstract Objective The aim of this study was to investigate the diagnostic potential of Krebs von den Lungen-6 (KL-6) in differentiating between malignant pleural effusion (MPE) induced by non–small cell lung cancer (NSCLC) and benign pleural effusion (BPE). Methods We collected 143 pleural effusion samples from August 2018 to March 2021. The samples included 91 cases of MPE and 52 cases of BPE. The KL-6 and other indicators in pleural effusion were detected. Results The level of pleural effusion KL-6 (pKL-6) in the MPE group was significantly higher than in the BPE group (Mann-Whitney U = 442.500, P = .000). The area under the curve (AUC) of pKL-6/pleural effusion adenosine deaminase (pADA) + pleural effusion carcinoembryonic antigen (pCEA)/pADA (AUC = 0.992) in diagnosing MPE was higher than that of pKL-6 alone (AUC = 0.903), with a sensitivity of 93.26% and specificity of 100%. Conclusion The measurement of pKL-6 can differentiate NSCLC-induced MPE from BPE. Furthermore, the combined detection of pKL-6/pADA and pCEA/pADA can significantly improve the diagnostic efficiency for distinguishing NSCLC-induced MPE.