Unexpectedly serum tumor marker results indicated that carbohydrate antigen 19-9, carbohydrate antigen 72-4, and alpha fetoprotein are all within normal ranges whereas cytokeratin-19-fragment (CYFRA21-1) and neuron-specific enolase (NSE) values elevated slightly (CYFRA21-1 3.75 ng/mL, normal <3.3 ng/mL; NSE 16.62 ng/mL, normal <16.3 ng/mL). Here, ENO2 is linked to neoplasm.