As GEP-NENs express somatostatin receptors (SSTRs), long-acting somatostatin analogs (SSAs) that are used for secretory syndrome and tumor control may lead to altered glucose metabolism.
<b>Conclusion:</b> [<sup>55</sup>Co]Co-DOTATATE demonstrated superior image contrast compared to [<sup>64</sup>Cu]Cu-DOTATATE and [<sup>68</sup>Ga]Ga-DOTATATE for PET imaging of somatostatin receptor expressing tumors, warranting translation into clinical trials.
Peptide receptor radionuclide therapy (PRRT) is among the most effective therapeutic options for metastatic NETs because of targeted delivery of radioactivity to the tumour via the somatostatin receptor (SSTR) and relatively low systemic toxicity.
Both everolimus and pasireotide inhibit the growth of thyroid cancer cell lines in vitro with varied efficacy that correlates with tumor origin and somatostatin receptor (SSTR) expression profile of the cell lines.
The high expression of somatostatin receptor 2 (SST2) in growth hormone (GH)-secreting tumors represents the rationale for the clinical use of somatostatin analogs (SSAs) in acromegaly.
Similarly to what was observed in the major ampulla, 3 histotypes were found: (i) ampullary-type somatostatin-producing tumors (ASTs, 10 cases), characterized by somatostatin expression in most tumor cells, focal-to-extensive tubulo-acinar structures, often with psammoma bodies, MUC1 reactivity, and no or rare membranous reactivity for somatostatin receptor type 2A; (ii) gangliocytic paragangliomas (3 cases), characterized by the coexistence of 3 tumor cell types: epithelioid, often reactive for pancreatic polypeptide, ganglion-like cells, and S100 reactive sustentacular/stromal cells; and (iii) ordinary nonfunctioning NETs (3 cases), resembling those more commonly observed in the extra-ampullary duodenum.
Here, we report a patient with an highly aggressive, dopamine-resistant prolactinoma, who only achieved biochemical and tumor control during pasireotide long-acting release (PAS-LAR) therapy , a second-generation somatostatin receptor ligand (SRL).
Tumor specimens of all included patients (n = 8) before and after the onset of a therapy with somatostatin analogs were analyzed and a micro-RNA expression profile (754 micro-RNAs) of each probe was generated.
Prognostic value of somatostatin receptor expressing tumor volume calculated from <sup>68</sup>Ga-DOTATATE PET/CT in patients with well-differentiated neuroendocrine tumors.
In poorly differentiated neuroendocrine tumours or medullary thyroid carcinoma, 18F-fluorodeoxyglucose PET/CT and dihydroxyphenylalanine PET/CT play an important role due to the limitations of the somatostatin receptor imaging in these tumour entities.
Patients with stable disease were characterized by a combination of both a high uptake on <sup>111</sup>In-DTPA-octreotide scan (uptake grade ≥ 3) and a positive somatostatin receptor type 2a (SSTR2a) expression of the tumor by immunohistochemistry.
Mice bearing CA20948 somatostatin receptor positive tumor xenografts were treated with <sup>177</sup>Lu-DOTATATE or sham-treated, and co-injected with <sup>111</sup>In-anti-γH2AX-TAT, <sup>111</sup>In-IgG-TAT control, or vehicle.
Using the established clinical efficacy of radiolabeled somatostatin analogs as a model, we demonstrate the ability of a fluorescent somatostatin analog to selectively target tumors that overexpress somatostatin receptor subtype-2 (SSTR2) and demonstrate utility for fluorescence-guided surgery (FGS).
Ga-DOTATATE is a radiolabeled somatostatin analog used for the detection and characterization of somatostatin receptor (SSR)-overexpressing tumors, particularly well-differentiated neuroendocrine tumors.
In accordance with the current consensus criteria, we recommend pasireotide LAR monotherapy as a second-line therapy in young patients who show tumor growth during first-generation somatostatin receptor ligand (SRL) therapy and in patients who show tumor growth during PEGV therapy.
Seventeen ileal NET patients and 36 pancreatic NET patients who underwent surgical resection between 2001 and 2018, who had pathology-confirmed liver metastases and confirmed tumorsomatostatin receptors, did not have MEN-1, and had no previous treatment were identified.
It has been shown that the expression of somatostatin receptors in the tumor might be of importance to select patients who could benefit from treatment with somatostatin analogues.
Somatostatin receptor imaging has previously been performed with a gamma camera using [<sup>111</sup>In]In or [<sup>99m</sup>Tc]Tc-labelled compounds, while [<sup>68</sup>Ga]Ga-labelled compounds and PET/CT imaging has recently become the gold standard for the diagnosis and management of these tumors.
We hypothesised that TAF-derived cytokines may play a role in tumour aggressiveness, and that their release can be inhibited by somatostatin analogues.