Insulinoma

Hypoglycemia is the term used to refer to lower than normal levels of blood sugar. This study will continue to research the causes of hypoglycemia. Patients involved in the study will be admitted to the Clinical Center of the National Institutes of Health and undergo tests for evaluating blood sugar. Patients will be required to refrain from eating for a set period of time and will undergo blood tests for insulin levels and several other specific diagnostic tests related to insulin secretion. The patients will be under supervision and will be provided with appropriate medical and surgical attention as needed.

This purpose of this study is to determine the ability of an 18F-fluoro-L-dihydroxyphenylalanine (18F-DOPA) PET (Positron Emission Tomography) scan to detect a focal lesion of hyperinsulinism and determine the location in patients with congenital hyperinsulinism, Beckwith Wiedemann Syndrome and suspected insulinoma. Safety data will be collected.

To evaluate the potential usefulness of 68Ga/18F-Exendin 4 positron emission tomography/computed tomography (PET/CT) for the diagnosis of primary and metastatic lesions in various GLP-1R-related disease patients.

Low blood sugars are known to cause brain damage in newborn babies. One of the most common causes of low blood sugars persisting beyond the new born period is a condition called congenital hyperinsulinism (HI). This is a disease whereby the pancreas secretes too much insulin and causes low blood sugars. Twenty to forty percent of these babies will have brain damage. There are two forms of this disease. In one form only a small part of the pancreas makes too much insulin (focal HI) and in the other, the whole pancreas make too much insulin (diffuse HI). Another very similar disease is insulinoma which occurs after birth, but also causes hyperinsulinism. If a surgeon could know which part of the pancreas has the focal lesion he could remove it and cure the patient. The purpose of this study is to investigate whether a new investigational drug called Fluorodopa F 18, when used with a PET scan, can find the focal lesion and guide the surgeon to remove it, thus curing the patient and preventing further brain damage.