Tumor marker levels were all negative: carcinoembryonic antigen (CEA), 1.8 ng/mL; carbohydrate antigen 19–9 (CA19-9), 9 U/mL; carbohydrate antigen 125 (CA125), 9 U/mL; neuron-specific enolase (NSE), 7.59 ng/mL; and 5-S-cysteinyldopa (5-S-CD), 2.7 nmol/L. This evidence concerns the gene ENO2 and neoplasm.