somatostatin receptor scintigraphy
A nuclear medicine imaging technique using radiolabeled somatostatin analogs to detect neuroendocrine tumors.
Full Definition
Somatostatin receptor scintigraphy (SRS) is a specialized nuclear medicine imaging modality that exploits the high expression of somatostatin receptors on most neuroendocrine tumors. The technique uses radiolabeled somatostatin analogs, typically 111In-pentetreotide (OctreoScan) or 68Ga-DOTATATE for PET imaging, to visualize primary tumors and metastatic deposits. This functional imaging approach is particularly valuable for staging, treatment planning, and monitoring response to therapy in patients with neuroendocrine tumors. Positive uptake on SRS also predicts responsiveness to somatostatin analog therapy and eligibility for peptide receptor radionuclide therapy (PRRT). The sensitivity varies by tumor type and location, with higher detection rates for well-differentiated tumors.
Usage
Usage note: Modern 68Ga-DOTATATE PET/CT has largely replaced older 111In-pentetreotide imaging.
In Context
- "Somatostatin receptor scintigraphy revealed multiple hepatic metastases not visible on conventional imaging." — Nuclear medicine report
- "The positive SRS uptake suggested the patient would benefit from octreotide therapy." — Treatment planning note