A recent study reveals that a novel PET scan can accurately identify benign tumors in the pancreas. Traditional scans frequently miss these insulinomas, which can lead to symptoms stemming from low blood sugar levels. If a tumor is detected, surgical options become available.
Recent research from Radboud University Medical Center indicates that a new PET scan is effective in identifying benign pancreatic tumors. Existing scan methods often overlook insulinomas, despite the symptoms caused by low blood sugar. Surgery can be performed once the tumor is located.
The pancreas is home to beta cells, which are responsible for producing insulin, a hormone that aids the body in absorbing and storing sugar from the blood, thus regulating blood sugar levels. In rare instances, these beta cells can malfunction and produce a benign tumor known as an insulinoma. While this tumor typically does not metastasize, it can still lead to serious issues due to excessive insulin production, resulting in low blood sugar levels.
Alternative to slicing pancreatic tissue
Marti Boss, the primary author of the study, explains that individuals with this condition often experience fatigue from low blood sugar and may frequently faint. “It’s a difficult disease, and obtaining a diagnosis can be a lengthy process. Blood tests can indicate low sugar levels but do not confirm whether a tumor is present or its location. Several imaging methods like CT, MRI, and PET scans exist, yet they do not always detect insulinomas.”
To address the issue, surgeons need to pinpoint the tumor’s location, as surgical removal would solve the problem. Martin Gotthardt, a Nuclear Medicine professor at Radboudumc, notes, “In the past, surgeons would sometimes remove sections of the pancreas blindly to locate the tumor. If it was positioned at the end, they risked removing the entire organ. While survival without a pancreas is possible, it can lead to severe diabetes and the constant need to manage blood sugar levels. Thus, a more effective scanning method was essential.”
A new approach
Gotthardt and his colleagues have created a novel scanning technique, termed the Exendin-PET scan, which enables precise identification of insulinomas. Their prior research focused on cases in children born with insulinomas; this latest effort includes findings from adult participants, where the tumors developed over time.
The study involved 69 adult participants suspected of having insulinomas. The Exendin-PET scan successfully identified tumors in 95% of those patients, as opposed to just 65% with the standard PET scan. Although combining it with CT and MRI usually yields results, in 13% of cases, the insulinoma was exclusive to the new scan. Boss stated, “We believe this new scan could potentially replace all other imaging techniques. Every insulinoma identified through the new scan was surgically removed, leading to complete cures for all patients, even those who had suffered for decades.”
Technology inspired by lizards
This innovative scan utilizes a compound derived from the saliva of the Gila monster, a lizard native to the United States’ desert regions. Gotthardt elaborates, “We discovered that this compound binds specifically to a tumor molecule known as the GLP1 receptor. However, the natural substance wasn’t stable in the human body, prompting us to develop a chemically stable version called Exendin. We then tagged it with a radioactive component for visibility in PET scans. This mildly radioactive Exendin effectively detects insulinomas.”
The next objective is to establish the Exendin-PET scan as the standard procedure for patients suspected of having an insulinoma. Researchers will evaluate how this scan enhances patients’ quality of life and the potential cost savings from eliminating the need for other scans like CT and MRI. Additionally, Gotthardt’s team is exploring the possibility of using Exendin in treating insulinomas in a new research initiative named LightCure.
