Classic serum tumor markers, such as carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), progastrin-releasing peptide (Pro-GRP), cytokeratin fragment (CYFRA) 21-1, squamous cell carcinoma-related antigen (SCC-Ag), cancer antigen (CA) 19-9, CA-125, CA15-3, and alpha-fetoprotein (AFP), have been widely used in the identification of MPE [9–11]. Here, ENO2 is linked to neoplasm.