Edotreotide gallium Ga-68

Agallium scanis a type ofnuclear medicinediagnostic investigation that uses either agallium-67(67Ga) orgallium-68(68Ga)radiopharmaceuticalto obtain images of a specific type of tissue, or disease state of tissue. Thegamma emissionof gallium-67 is imaged by agamma camera, while thepositron emissionof gallium-68 is imaged bypositron emission tomography(PET).Galliumsaltslike galliumcitrateand galliumnitratemay be used. The form of salt is not important, since it is the freely dissolved gallium ion Ga3+which is active.As they are isotopic, Both67Ga and68Ga salts have the same uptake mechanisms.The gallium(III) is rapidly bound by transferrin, which then preferentially accumulates in tumors, inflammation, and both acute and chronic infection,allowing these pathological processes to be imaged. Gallium is particularly useful in imagingosteomyelitisthat involves the spine, and in imaging older and chronic infections that may be the cause of afever of unknown origin.Due to lack of disease specificity, imaging with radioactive gallium(III) salts or complexes, such as67Ga citrate, has gradually become less important over time and is rarely used these days. However, the mentioned gallium(III) radionuclides, particularly68Ga, are frequently used as radiolabels for peptides, proteins, oligonucleotides, drugs, and drug-like substance, turning these from regular pharmaceuticals into radiotracers. A popular class of such radiopharmaceuticals is formed by68Ga-labeled small-molecule inhibitors for prostate-specific membrane antigen (PSMA), which are increasingly used for prostatecancerimaging. Furthermore, Gallium-68 labeled octreotide analogs, such as68Ga-DOTATOC, were among the first clinically successful68Ga PET tracers and have meanwhile replacedindium-111labeled octreotides for diagnostic imaging of somatostatin receptor positive neuroendocrine tumors. Investigations with68Ga-labeled peptides etc. are however not commonly referred to as 'gallium scan'. Usually they are named after the addressed target or labeled bioligand, e.g., 'PSMA scan' or 'DOTATOC scan'.