MSLN and Pleural effusion: As a marker for differentiating pleural effusion in MPM, SLPI is described only in a report by Blanquart et al.16; however, in their report, three markers (CCL2, galectin-3, and SMRP) were reportedly effective, and if they were used properly, MPM could be differentiated from other diseases that cause pleural effusion, with an AUC of 0.968.