Atypical carcinoid | Foregut | 5-HTP, histamine | Pruritus, cutaneous wheals, bronchospasm | Atypical carcinoid |
Carcinoid | Small intestine, lung (< 5%),* pancreas (< 1%)* | Serotonin, tachykinin, prostaglandins | Flushing, diarrhea, valvular disease, bronchospasm | Carcinoid |
Insulinoma | Pancreatic β cells | Insulin, proinsulin | Hypoglycemic symptoms | Whipple triad |
Gastrinoma | Gastrinoma triangle† | Gastrin | Diarrhea, peptic ulcer disease | Zollinger–Ellison |
Glucagonoma | Pancreatic α cells | Glucagon | Diabetes, deep vein thrombosis, depression, dermatitis (necrolytic migratory erythema) | 4D syndrome |
Somatostatinoma | Pancreatic δ cells | Somatostatin | Diabetes, cholelithiasis, steatorrhea, weight loss, achlorhydria | Somatostatinoma |
VIPoma | Non-β islet cells | Vasoactive intestinal peptide | Watery diarrhea (profuse), hypokalemia, achlorhydria | Verner–Morrison (WDHA syndrome) |
ACTHoma | Lung (4%)* | ACTH | Fat redistribution/obesity, facial plethora, skin atrophy/easy bruising/striae, proximal myopathy, hyperglycemia | Cushing syndrome |