GRP and neoplasm: Tumor marker levels showed an elevated progastrin-releasing peptide (ProGRP, 127.28 pg/mL; normal ≤67.42), while neuron-specific enolase (NSE, 15.81 ng/mL; normal ≤16.5) and carcinoembryonic antigen (CEA, 2.90 ng/mL; normal ≤4.5) remained within normal ranges.