NSE is an important tumor marker in the serum of patients with lung cancer.20, 21 Elevated serum NSE level is also associated with neuroblastoma, neuroendocrine neoplasms, renal cell carcinoma, and other diseases.22, 23 As a neuroendocrine tumor, we hypothesized that MTC could also secrete NSE theoretically. Here, ENO2 is linked to neuroendocrine neoplasm.