Clinical Trial: [68 Ga]-DOTANOC PET/CT in GEP-NETs

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional




Official Title: Impact of [68 Ga]-DOTANOC PET-CT on the Management of Gastroenteropancreatic Neuroendocrine Tumors (GEP-NETs): Prospective, Multicentric Study.

Brief Summary:

Somatostatin receptors are overexpressed in GEP-NETs and can be visualized in vivo by radiolabeled somatostatin-analogs.

During the last decades, conventional scintigraphy using 111In-DTPA-Octreotide (often named somatostatin receptor scintigraphy or SRS) was considered as the gold standard nuclear imaging technique in the evaluation of GEP-NETs. However, SRS may be suboptimal in this clinical setting because of the low intrinsic resolution of the technique and its selectivity for SST2 only. Its overall sensitivity is estimated to 60-70% (per lesion analysis), even when using the most recent SPECT-CT cameras. MRI have also a higher sensitivity than CT and SRS for the detection of liver metastases from GEP-NETs.

In recent years, positron emission tomography (PET) imaging, a high resolution and sensitive technology, has gained an increasing role in oncology. It has also been evaluated in GEP-NETs with somatostatin agonists (SSTa) radiolabelled with Gallium-68 [68Ga], a positron emitter with very promising results. Its diagnostic sensitivity is clearly superior to SRS and many European centers have already replaced SRS by [68Ga]-PET-SSTa.

Currently, three different [68Ga]-coupled peptides can be used in trials: DOTA-TOC, DOTA-TATE and DOTA-NOC with excellent affinities for SST2 (IC50: 2.5; 0.2 and 1.9 nM, respectively). Sensitivities of DOTA-TOC and DOTA-TATE PET/CT are quite similar.

[68Ga]-DOTANOC which also binds to SST5 was recently found to detect significantly more lesions than the SST2-specific radiotracer [68Ga]-DOTATATE in patients with GEP-NETs but this requires further evaluation.

It is therefore important to determine the interest of [68Ga]-DOTANOC combined with the