68GaDOTATATE

68Ga-DOTATATE is a radiopharmaceutical used in positron emission tomography (PET) imaging. It combines the somatostatin analog DOTATATE with the radioactive isotope gallium-68, enabling visualization of somatostatin receptor expression in vivo. DOTATATE binds with high affinity to somatostatin receptor subtype 2 (SSTR2), which is commonly overexpressed in many neuroendocrine tumors and in some meningiomas and other neoplasms.

The imaging agent targets somatostatin receptors, particularly SSTR2, allowing high-contrast PET images of receptor-positive lesions. This aids in localization, staging, and restaging of neuroendocrine tumors and can help in the assessment of other SSTR-expressing tumors. It is also used to select patients for peptide receptor radionuclide therapy (PRRT) with agents such as 177Lu-DOTATATE.

Production and radiochemistry rely on a gallium-68 generator as the source of Ga-68. DOTATATE is radiolabeled with Ga-68 typically under heat in an acetate buffer, producing a compound with high radiochemical purity (often over 95%). The radiopharmaceutical is administered by intravenous injection, and imaging is usually performed about 45 to 60 minutes after injection.

Administration and dosimetry vary by protocol, but typical activities are in the range of 100 to 200 MBq, adjusted for patient factors. 68Ga-DOTATATE generally has a short uptake window and is favored for providing timely, whole-body assessment of somatostatin receptor–positive disease.

Safety and regulatory aspects include consideration of radiation exposure and standard precautions. It is usually avoided during pregnancy and lactation, and regulatory approvals vary by country (for example, FDA-approved formulations exist in several regions for NET imaging).