This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
[{'content': 'For which one of the following tumors Gastrin is a biochemical marker : \nSelect and explain. \nA. Medullary carcinoma of thyroid, B. Pancreatic neuroendocrine tumour, C. Pheochromocytoma, D. Gastrointestinal stromal tumor', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Pancreatic neuroendocrine tumor Gastrin is secreted by Gastrinomas.Gastrinomas are neuroendocrine tumors found in the duodenum (50 to 70%) pancreas (20 to 40%) andOther intraabdominal sites (mesentery, lymph nodes, biliary tract, liver, stomach, ovary)Excess gastrin secretion leads to Zollinger Ellison SyndromeAlso, knowVerner-Morrison syndrome caused by secretion ofVasoactive intestinal polypeptide (VIP) Verner-Morris on syndrome is also known as pancreatic cholera or WDHA syndrome (excessive watery diarrhea, hypokalemia & achlorhydria)", 'role': 'assistant'}]