Related Experiment Video
Updated: May 9, 2026

A Whole Body Dosimetry Protocol for Peptide-Receptor Radionuclide Therapy (PRRT): 2D Planar Image and Hybrid 2D+3D SPECT/CT Image Methods
Published on: April 24, 2020
Kidney dosimetry in ¹⁷⁷Lu and ⁹⁰Y peptide receptor radionuclide therapy: influence of image timing, time-activity
F Guerriero1, M E Ferrari, F Botta
1Medical Physics Department, European Institute of Oncology, 20141 Milan, Italy.
Abstract:
Kidney dosimetry in (177)Lu and (90)Y PRRT requires 3 to 6 whole-body/SPECT scans to extrapolate the peptide kinetics, and it is considered time and resource consuming. We investigated the most adequate timing for imaging and time-activity interpolating curve, as well as the performance of a simplified dosimetry, by means of just 1-2 scans. Finally the influence of risk factors and of the peptide (DOTATOC versus DOTATATE) is considered. 28 patients treated at first cycle with (177)Lu DOTATATE and 30 with (177)Lu DOTATOC underwent SPECT scans at 2 and 6 hours, 1, 2, and 3 days after the radiopharmaceutical injection. Dose was calculated with our simplified method, as well as the ones most used in the clinic, that is, trapezoids, monoexponential, and biexponential functions. The same was done skipping the 6 h and the 3 d points. We found that data should be collected until 100 h for (177)Lu therapy and 70 h for (90)Y therapy, otherwise the dose calculation is strongly influenced by the curve interpolating the data and should be carefully chosen. Risk factors (hypertension, diabetes) cause a rather statistically significant 20% increase in dose (t-test, P < 0.10), with DOTATATE affecting an increase of 25% compared to DOTATOC (t-test, P < 0.05).
Related Concept Videos
Imaging Studies I: Kidney, Ureter, and Bladder Studies
Imaging Studies VII: Vascular Imaging
Radiological Investigation III: Pulmonary Angiogram and PET Scan
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...
Imaging Studies II: Positron Emission Tomography and Scintigraphy
Fundamental Principles of PET
Radiological Investigation I: X-ray and CT
Imaging Studies III: Computed Tomography

