A new PET scan developed by researchers at Radboud University Medical Center reliably detects benign pancreatic tumors, known as insulinomas, which are often missed by current imaging techniques. These tumors, though non-cancerous, can cause significant health issues due to excessive insulin production, leading to low blood sugar levels and associated symptoms. Once detected, these tumors can be surgically removed.
Insulinomas originate in the pancreas’ beta cells, which are responsible for producing insulin—a hormone that regulates blood sugar by helping the body absorb it from the bloodstream. Although these tumors rarely spread, they result in the overproduction of insulin, causing low blood sugar levels that can lead to fatigue and fainting.
Traditional scans, such as CT, MRI, and PET, often fail to detect insulinomas, delaying diagnosis and treatment. According to Marti Boss, lead author of the study, blood tests can indicate the presence of low blood sugar but cannot confirm the location or existence of a tumor, making it difficult to plan treatment. Historically, surgeons sometimes had to remove large portions of the pancreas to locate the tumor, which could lead to the removal of the entire organ, causing severe diabetes and lifelong management of blood sugar levels. Therefore, a more accurate scan was necessary.
In response, Professor Martin Gotthardt and his team developed a new Exendin-PET scan, which can accurately pinpoint insulinomas. Previous research demonstrated its effectiveness in children with congenital insulinomas, and now, new findings show its success in adults with gradually developed tumors.
In a study of 69 adults with suspected insulinomas, the Exendin-PET scan detected tumors in 95% of patients, a significant improvement over the 65% detection rate of traditional PET scans. In 13% of cases, the tumor was visible only on the new scan. All tumors identified by the Exendin-PET scan were successfully removed, resulting in complete recovery for all patients, some of whom had been suffering from the condition for decades.
As reported by news-medical.net, the new scan is based on a substance found in the saliva of the Gila monster, a lizard native to U.S. desert regions. This substance binds to a specific molecule on insulinomas, the GLP1 receptor. The naturally occurring version wasn’t stable in the human body, so the researchers created a more chemically stable version called Exendin, attaching a radioactive substance to make it visible on a PET scan. This mildly radioactive version of Exendin reliably identifies insulinomas.
The next phase of research involves introducing the Exendin-PET scan into clinical practice as the standard diagnostic tool for suspected insulinoma cases. Researchers will now evaluate how the scan enhances patient outcomes and assess potential cost savings by reducing the need for other imaging techniques like CT and MRI. Gotthardt’s team is also exploring the use of Exendin in the treatment of insulinomas through a new project, LightCure.