Related Experiment Video
Updated: Aug 5, 2026
Harnessing the Bioorthogonal Inverse Electron Demand Diels-Alder Cycloaddition for Pretargeted PET Imaging
Published on: February 3, 2015
Localization of Neuroendocrine Tumors Using Somatostatin Receptor Imaging With Indium-111-Pentetreotide (OctreoScan)
Abstract:
BACKGROUND: Many imaging methods have been used to detect neuroendocrine tumors of the gastrointestinal system. There is no gold standard for identifying the location of primary tumors and their potential metastases, and most conventional imaging techniques cannot detect tumors less than 1.0 cm in size. METHODS: The authors have investigated the use of 111-In-pentetreotide as an imaging agent for abdominal neuroendocrine tumors. RESULTS: The agent is cleared rapidly by the kidneys and is primarily excreted intact with a biologic half-life of six hours. The largest radiation burden is to the spleen and kidneys. A nine-center study conducted in Europe involved 365 patients with gastroenteropancreatic neuroendocrine tumors that were also imaged by other methods. The results of 111-In-pentetreotide were in agreement with those obtained by other methods for 79% of tumor locations. An additional 110 tumor localizations were detected that were not seen with conventional methods. The smallest gastrinoma imaged by 111-In-pentetreotide was a 4-mm duodenal tumor. CONCLUSIONS: Scintigraphy with 111-In-pentetreotide is effective in visualizing various somatostatin receptors characteristic of neuroendocrine tumors of the gastrointestinal tract. Insulinomas, however, are not well imaged. Concurrent computed tomography scanning is advised to minimize the risk of missing liver metastases.
Insights
111-In-pentetreotide scintigraphy effectively detects gastrointestinal neuroendocrine tumors, including small ones missed by conventional imaging. Concurrent CT scanning is recommended for liver metastases.
Area of Science:
- Nuclear Medicine
- Oncology
- Gastroenterology
Background:
- Conventional imaging techniques struggle to detect small gastrointestinal neuroendocrine tumors (<1.0 cm).
- A definitive gold standard for locating primary tumors and metastases is lacking.
- Neuroendocrine tumors (NETs) present diagnostic challenges due to their varied locations and potential for metastasis.
Purpose of the Study:
- To evaluate the efficacy of 111-In-pentetreotide scintigraphy for imaging abdominal neuroendocrine tumors.
- To compare the detection rates of 111-In-pentetreotide with conventional imaging methods.
- To assess the safety and effectiveness of 111-In-pentetreotide in a large patient cohort.
Main Methods:
- A nine-center European study involving 365 patients with gastroenteropancreatic neuroendocrine tumors.
- Utilized 111-In-pentetreotide as a radiotracer for scintigraphy.
- Compared scintigraphy results with other conventional imaging modalities.
Main Results:
- 111-In-pentetreotide demonstrated agreement with conventional methods in 79% of tumor locations.
- Detected 110 additional tumor localizations not identified by conventional techniques.
- Successfully imaged a 4-mm duodenal gastrinoma, highlighting sensitivity for small tumors. The agent is cleared rapidly by the kidneys with a six-hour half-life, with spleen and kidneys receiving the highest radiation dose.
Conclusions:
- Scintigraphy with 111-In-pentetreotide is effective for visualizing somatostatin receptors on gastrointestinal neuroendocrine tumors.
- Insulinomas are not optimally imaged with this agent.
- Concurrent computed tomography (CT) scanning is advised to improve the detection of liver metastases and minimize missed diagnoses.
More Related Videos
Related Concept Videos
01:29Positron Emission Tomography
One of the main requirements of a PET scan is a positron-emitting radioisotope, which is produced in a cyclotron and then attached to a substance used by the part of the body being...
01:25Imaging Studies II: Positron Emission Tomography and Scintigraphy
Fundamental Principles of PET