The Cutaneous Manifestations of the Functioning Carcinoid

The purpose of this communication is not to review the extensive literature that has appeared concerning this recently recognized syndrome of functioning carcinoid but to review for dermatologists the salient clinical features, especially the cutaneous ones, that may lead to recognition and diagnosis. Since 1952 and 1953, when four independent reports1-4appeared concerning a new syndrome, many additional reports of cases, experimental work, and the pathogenesis of this previously unidentified symptom complex, called the "functioning carcinoid" or the "carcinoid syndrome," have been published.5-7The original reports were actually the outcome of much previous work by physiologists and others concerning the physiology of serotonin and enteramine, which were both subsequently shown to be 5-hydroxytryptamine.5-7Lembeck8first demonstrated that carcinoid tumors may contain large amounts of 5-hydroxytryptamine. It is the liberation of 5-hydroxytryptamine into the blood stream by the cells of