Chemical name and alternative names

Chemical structure

2,2′,2″-(10-(2-((2-(1-(2-hydroxy-2,2-diphosphono-ethyl)-1H-imidazol-4-yl)ethyl)-amino)-2-oxoethyl)-1,4,7,10-tetraazacyclo-dodecane-1,4,7-triyl)triacetic acid

DOTA-ZOL;

DOTAZOL

Route of Synthesis

Chelation of generator produced 68Ga-chloride with DOTA-zoledronate in acetate buffer at elevated temperature, followed by cartridge purification (Meckel et al. 2017).

Normal Biodistribution and Excretion

High accumulation is seen in the skeleton as biological target and kidneys and bladder as organs of excretion. Faint accumulation is seen in liver, spleen, and salivary glands. Activity is seen in the renal parenchyma within 2.5 min of injection, but renal clearance is rapid and only minimal activity is evident at 45 min (Khawar et al. 2019).

Activity Administered

150 MBq.

Radiation Dosimetry

Effective dose equivalent (mSv/MBq): 0.017 (2.6 mSv/150 MBq).

Organ doses (mGy/MBq): urinary bladder wall, 0.37; osteogenic cells, 0.040; kidneys, 0.031 (Khawar et al. 2019).

Patient Preparation

The patient should be well hydrated to reduce the radiation dose to the kidneys and bladder.

Clinical Utility

It is anticipated that utility will be similar to 18F-fluoride (though with much reduced radiation dose) and the 99mTc diphosphonate bone scan agents. In particular, may be useful prior to palliative therapy with 177Lu- or 225Ac-DOTA-ZOL (Meisenheimer et al. 2020).