Insulinomas: Benign Pancreatic Tumors

4. Further Investigations

To investigate the diagnosis further, the doctor will require their patient to go on a 72-hour fast, during which time they will monitor blood sugar and the levels of insulin, C-peptide, and proinsulin. These latter compounds are involved in the manufacture of insulin in the pancreas and their levels will be high in people with an insulinoma. Normally, fasting reduces insulin production.

The diagnosis of an insulinoma may not be obvious, as the symptoms could be attributed to psychiatric, cardiac, or neurological disorders. This may lead to delayed diagnosis -- 50% of insulinomas are not diagnosed until five years after the onset of the first symptoms.

Once the diagnosis has been made, surgical removal is the most effective management.