Whole Body 111In-exendin-4 Imaging Study in Insulinoma Patients

Study Overview
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Brief Summary
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The purpose of this study is to determine whether the investigators' new imaging modality (111In-exendin-4) has advantages in detecting insulinomas in comparison to conventional imaging.

Detailed Description
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Insulinomas arise from pancreatic cells and are the most frequent hormone-active tumours of the pancreas. Insulinomas produce insulin and can become life threatening if they cannot be localised and removed surgically. Complete tumour resection cures most patients, hence surgery is the treatment of choice for begin and malignant insulinomas. The potential for surgical cure necessitates accurate tumour localisation before surgery because preoperative imaging facilitates the detection of small localised, multiple and metastatic insulinomas. However, the successful localisation of insulinomas is an challenging problem since approximately 30% of insulinomas cannot be visualised radiographically. A novel nuclear medicine scanning method using radioactive exendin-4 (111In-exendin-4) has recently been developed for imaging of insulinomas. 111In-exendin-4 accumulates specifically in insulinoma cells via the glucagon-like peptide-1 (GLP-1) receptor. The accumulation of 111In-exendin-4 can be visualised by the use of a special camera (Single Photon Emission Computed Tomography (SPECT) camera) that detects radioactivity and lights up tumours as hot spots. The decision to perform surgery is independent of this study. If surgery is performed a small sample of the tumor will be used for identifying the sites where 111In-exendin-4 binds to the tumor.

Official Title
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The Physiology of Glucagon-like-peptide-1 Receptor Expression in Patients With Endogenous Hyperinsulinism - Correlation With Histopathology

Conditions
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Hyperinsulinism, Hypoglycemia, Insulinoma

Intervention / Treatment
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* Other: 111In-exendin-4 imaging


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Biochemically proven endogenous hyperinsulinism confirmed by hypoglycaemia with neuroglycopenic symptoms, inadequately high serum insulin and C-peptide concentrations and negative sulfonylurea screening as well as low serum beta-hydroxybutyrate concentrations Able and willing to provide written informed consent Exclusion Criteria: Renal insufficiency (creatinine > 140 micromol/l) Pregnancy or positive pregnancy test which will be performed in all patients without contraception and aged < 50 years Allergy to exendin-4 (Byetta®)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: 111In-exendin-4 imaging|90-100 megabecquerel (MBq) (30 microgram or less) 111In-exendin-4 IV once|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Detection of insulinomas, cure rate |  | one year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Glucagon-like peptide-1 receptor targeting, Insulinoma imaging, Exendin-4, molecular imaging