Elevated NSE values are known to be present in about 60–80% of patients with small cell lung carcinoma, neuroblastoma, seminoma, and, in some patients, with benign CNS tumors, neuroendocrine neoplasia—medullary thyroid carcinoma, pancreatic carcinoma, Merkel cell carcinoma, carcinoid tumors; however, there is no published data with the finding of increased NSE values in ASD. This evidence concerns the gene ENO2 and carcinoid tumor.