Carcinoid Tumors: Current Concepts in Diagnosis and Treatment Carcinoid tumors belong to the family of neuroendocrine tumors which derive from the neuroendocrine cell system, widely distributed in the body. These tumors are rather rare, with age-adjusted incidence rates for all types of carcinoids of 1.2-2.1/100,000 population/year [1]. The incidence of the car- cinoid syndrome (see below) is about 0.5/100,000 [2]. The term “carcinoid” is at the moment under debate among spe- cialists working in this field. The term was originally intro- duced by Oberndorfer in 1907, who described a type of tumor in the gut with less malignant behavior [3]. Read More →