Gallium-68 DOTATATE
Updates to Article Attributes
Gallium-68 DOTATATE (or Ga-68 DOTATATE) is a PET radiotracer that is useful for evaluating primary and metastatic well-differentiated neuroendocrine tumours. It is a form of somatostatin-receptor (SSTR) functional imaging and most often combined with cross-sectional imaging in the form of PET-CT.
Terminology
Gallium-68 DOTATATE is synthesised from three main components:
- gallium (Ga) radiotracer
- linked, via a chemical macrocyclic chelator, known as
tetraazacyclododecaneDOTA (or tetraxetan); IUPAC name: 1,4,7,10-tetraazacyclododecane-tetraacetic acid(DOTA) - to the short-chain peptide Tyr3-octreotate (TATE)
Pathology
Ga-68 DOTATATE has shown improved accuracy for detection relative to indium-111 pentetreotide SPECT-CT 1. It binds SSTR subtype 2 and binds 100 times more avidly than indium-111 pentetreotide 2.
There are other forms:
- DOTATOC: DOTA-d-Phe1-Tyr3-octreotide
- DOTANOC: DOTA-1-Nal3-octreotide
These have an affinity for different somatostatin receptors, SSTR subtypes 3 and 5 and SSTR subtype 5, respectively 3.
Radiographic features
There is normal Ga-68 DOTATATE uptake in the pituitary gland, spleen, liver, adrenal glands, and urinary tract 4,5.
The salivary glands and thyroid show faint to mild homogeneous uptake 4,5.
-<li>linked, via a chemical chelator, known as tetraazacyclododecane-tetraacetic acid (DOTA)</li>- +<li>linked, via a chemical macrocyclic chelator, known as DOTA (or tetraxetan); IUPAC name: 1,4,7,10-tetraazacyclododecane-tetraacetic acid</li>