Related Experiment Video
Updated: Sep 19, 2025
![Quantitative [18F]-Naf-PET-MRI Analysis for the Evaluation of Dynamic Bone Turnover in a Patient with Facetogenic Low Back Pain](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58491.jpg&w=3840&q=50)
Quantitative [18F]-Naf-PET-MRI Analysis for the Evaluation of Dynamic Bone Turnover in a Patient with Facetogenic Low Back Pain
Published on: August 8, 2019
Assessing the frequency and accuracy of morphologic changes of focal bone lesions on [68Ga]Ga-PSMA-11 PET/CT in
Thibika Sivakumar1,2, Jakob Heimer2,3, Stephan Beintner-Skawran1
1Department of Nuclear Medicine, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
Background:
In [18F]F-PSMA-1007 PET imaging, focal bone uptake without morphological correlate (MC) on CT, is often classified as benign. In [68Ga]Ga-PSMA-11, intense focal uptake without MC in a classical location is considered suspicious. The prevalence of focal bone uptake with or without MC on [68Ga]Ga-PSMA-11 PET/CT remains unclear.
Methods:
This single-center, retrospective study included patients who underwent a [68Ga]Ga-PSMA-11 PET/CT scan for initial staging or biochemical recurrence (BCR) of prostate cancer between 04/16 - 11/21, with written informed consent for use of clinical data and adequate follow-up. For each patient with focal PSMA accumulation in the bones, up to three of these lesions were scored based on PSMA-RADS 2.0 and a clinical interpretation of suspicion for malignancy including clinical information was provided. In addition, MC on CT were assessed. A composite reference standard including imaging and clinical follow-up data was used.
Results:
Out of 824 patients, 323 met eligibility criteria, with 101 showing PSMA-positive bone lesions. 176 lesions were included, 25% of 61 in the staging cohort had no MC, of which 73% were malignant. In the BCR group, 52% of 115 lesions were without MC, of which 48% were malignant. The sensitivity/specificity reached with PSMA-RADS 2.0, and MC on CT was 100%/100%and 78%/36% for staging, and 83%/100% and 60%/72% for BCR, respectively.
Conclusion:
Focal [68Ga]Ga-PSMA-11 positive lesions without MC on CT are frequent, especially on scans for BCR, with the majority being malignant. Considering PSMA-RADS 4 lesions on [68Ga]Ga-PSMA-11 on staging exams, significantly improves the accuracy. Incorporating clinical information and considering PSMA-RADS 3B can further improve the sensitivity for BCR scans.
