somatostatin receptor expression
Presence and density of somatostatin receptors on neuroendocrine tumor cells, determining treatment eligibility and imaging sensitivity.
Full Definition
Somatostatin receptor expression refers to the presence, type, and density of somatostatin receptors (particularly subtypes 2, 3, and 5) on the surface of neuroendocrine tumor cells. This expression determines the tumor's susceptibility to somatostatin analog therapy and its visibility on somatostatin receptor imaging studies. High somatostatin receptor expression correlates with better response to octreotide and lanreotide therapy, as well as strong uptake on gallium-68 DOTATATE PET imaging. Expression levels can be assessed through immunohistochemistry on tumor tissue or functionally through receptor imaging. Tumors with high receptor expression are candidates for peptide receptor radionuclide therapy, while those with low expression may require alternative therapeutic approaches.
Usage
Usage note: Specify receptor subtype when known; correlate with imaging findings and treatment response.
In Context
- "High somatostatin receptor expression on immunohistochemistry predicted excellent response to octreotide therapy." — Pathology correlation
- "The tumor's strong somatostatin receptor expression made it an ideal candidate for lutetium-177 DOTATATE therapy." — Treatment selection