<prompt> Answer this question truthfullyCan you provide an overview of Insulinoma?  <response>: <reason> Laboratory findings consistent with the diagnosis of insulinoma include serum glucose 55 mgdL; serum insulin 5-10 μUmL; serum C-Peptide 200 pmolL and serum proinsulin 22 pmolL. Patients with insulinoma may have elevated insulin to glucose ratio 0.4, which is usually suggestive of insulinoma after a 72-hour fast test as a gold standard test. One-thirds or 33 patients have clinical symptoms within 12 hours of fasting, 80 develop within 24 hours, 90 develop within 48 hours and 100 develop within 72 hours. 