POMC and neoplasm: Olfactory NB (esthesioneuroblastoma), a rare neuroectodermal tumor, arises from the olfactory neuroepithelium, and the release of adrenocorticotropin hormone (ACTH) from this tumor has rarely been observed; however, olfactory NB can cause ectopic ACTH syndrome (even long after the initial clinical treatment) because the presence/release of ACTH from olfactory NB cells has been reported [93,94,95,96].