ENO2 and squamous cell carcinoma: Malignancy was suspected, and some tumor markers were examined on the same day, including carcinoembryonic antigen (CEA), carbohydrate antigen 19–9 (CA19–9), neuron-specific enolase (NSE), progastrin-releasing peptide (ProGRP), squamous cell carcinoma (SCC), cytokeratin fragment (CYFRA), sialyl Lewis X-i antigen (SLX), and soluble interleukin-2 receptor (sIL-2R).