Gallium (68ga) Dotatate

What it is and how it works

68Ga-DOTATATE is the somatostatin analogue octreotate conjugated to the chelator DOTA and labelled with gallium-68. It binds with high affinity to somatostatin receptors, particularly subtype 2 (SSTR2), which are over-expressed by most well-differentiated neuroendocrine tumours, allowing PET localisation of receptor-positive disease.

Indications

PET imaging for localisation, staging and follow-up of somatostatin receptor-positive neuroendocrine tumours in adults and children, and selection of patients for peptide receptor radionuclide therapy (e.g. lutetium-177 DOTATATE).

Dosage and administration (summary)

Dosing is individualised according to the imaging protocol (activity based on body weight) and administered by nuclear medicine specialists as a single intravenous injection, with imaging about 40–90 minutes later.

Contraindications

Hypersensitivity to the active substance or excipients.

Warnings and precautions

Somatostatin analogue therapy can reduce tracer uptake, so imaging is ideally timed just before the next dose of long-acting analogue. Physiological and benign uptake (e.g. pancreatic uncinate process, inflammation, splenules) may cause false positives; radiation exposure should be minimised and patients should hydrate and void.

Pregnancy

Generally avoided in pregnancy unless essential, because of fetal radiation exposure.

Storage and supply

Prepared from a kit and gallium-68 eluate and used within its short shelf-life, kept at room temperature in appropriate radiation shielding.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.