ESTIMATION OF THE ORGAN ABSORBED DOSES AND EFFECTIVE DOSE FROM Ga-68-PSMA-11 PET SCAN

Abstract

Ga-68-PSMA-11PET/CT has been proven to have high clinical value for imaging of prostate cancer and rapidly gained popularity. In this study, we aimed to investigate absorbed doses of Ga-68-PSMA-11. Seven patients (mean age = 66.9 +/- 6.6 years, range: 57-79 years) were enrolled in the study. Whole body PET images were acquired with multiple time points. MIRD method, NUKFIT and OLINDA/EXM software were used for dosimetry calculations. Kidneys, bladder wall, salivary and lacrimal glands received the highest absorbed dose. Estimated absorbed doses to these organs after injection of 150 MBq Ga-68-PSMA-11 were 37.0, 12.6, 14.4 and 6.3 mSv, respectively. Effective dose from PET scanning with 150 MBq injected Ga-68-PSMA-11 was 2.5 mSv. In conclusion, Ga-68-PSMA- 11 has a favorable dosimetry profile similar to the Ga-68 labeled octreotide analogs, which are used safely in routine clinical practices for many years. No adverse effects were reported. The kidneys were the dose-limiting organs.