Table 1.

Symptoms and signs of carcinoid syndrome.

Symptom	Frequency %	Characteristics	Involved mediators
Flushing	90 9	Foregut: long-lasting, purple 9-11	Catecholamines, 5-HT, histamine, substance P 10,11
		Midgut: short-lasting, pink to red color, face and trunk, can occur several times a day for a few minutes 9-11	Catecholamines, histamine, substance P, prostaglandins 10,11
Diarrhea	60-80 14	Secretory: intermittent accompanied by abdominal cramping 14,15	Gastrin, 5-HT, histamine, prostaglandins, VIP 16,19
Abdominal pain	35	Progressive 54	Small bowel obstruction, hepatomegaly, ischemia 2
Bronchospasm	15 20	Wheezing 20	Histamine, 5-HT 20
Pellagra	5 31	Dermatitis, diarrhea, dementia 31	Niacin deficiency
CHD	19-60 32,33	Dyspnea, holosystolic murmur radiating to the right side of the chest 32	5-HT, bradykinins, tachykinins, activin A, tissue growth factor 32
Mesenteric Fibrosis	50 53	Ischemia of vessels: decreased absorption of nutrients, ascites, intestinal obstruction, ureteral obstruction 54	5-HT, TGF-beta 53,58