Carcinoid tumors represent a family of diseases derived from neuroendocrine cells. These tumors were first described by Langhans in 1867 but were not described in detail until Lubarsch described them in 1888. The name karzinoide was not used until 1907 by Oberndorfer and was chosen to reflect his idea that these were benign growths. However, these tumors have a wide range of clinical presentations and outcomes from benign to malignant. Clinicians must recognize the nature of carcinoid disease, because these often have a significantly different clinical course than typical carcinomas occurring within the body. Additionally, with few exceptions, neuroendocrine tumors (NETs) comprise a tiny fraction of tumors within any specific organ. These neoplasms cause <1 % of all malignancies in the United States, currently occurring at a rate of 2.5–4.5/100,000 people.
NETs can arise in...