[¹⁸F]PSMA‐1007 renal uptake parameters: Reproducibility and relationship to estimated glomerular filtration rate

Abstract

Background Scintigraphy with technetium‐99m‐labelled dimercaptosuccinic acid ([99mTc]Tc‐DMSA) is widely used for renal cortical imaging. Uptake of [99mTc]Tc‐DMSA has been shown to correlate with glomerular filtration rate (GFR). Prostate‐specific membrane antigen (PSMA) radiopharmaceuticals used for positron emission tomography (PET) show high renal uptake and are being investigated for renal imaging. [68Ga]Ga‐PSMA‐11 PET parameters have been shown to correlate with estimated GFR (eGFR). The aim of this study was to investigate the relationship between renal [18F]PSMA‐1007 uptake and eGFR. Methods Hundred and eighty‐five patients underwent PET imaging at 1 and 2 h after injection of 4.0 ± 0.2 MBq [18F]PSMA‐1007. Serum creatinine levels were measured and GFR estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) and Modification of Diet in Renal Disease (MDRD) equations. Fifteen patients were excluded due to missing or incorrect data. Thus, data from 170 patients were analyzed. Kidneys were segmented in the PET images using a convolutional neural network with manual correction. For each kidney, mean standardized uptake value (SUVmean) and segmentation volume in millilitres were measured. Linear regression analyses were performed with eGFR as the outcome variable. Results Variation in the eGFR values was explained to a significant degree by SUVmean and renal segmentation volume in both the 1 and 2 h images. This correlation was stronger for CKD‐EPI eGFR (1 h R2 = 0.64; 2 h R2 = 0.64) than for MDRD eGFR (1 h R2 = 0.47; 2 h R2 = 0.45). Conclusion Renal [18F]PSMA‐1007 uptake parameters correlate with eGFR and are indicative of renal cortical function.

An exploratory study of unexplained concentration of 18F-PSMA-1007 in the bladder for prostate cancer PET/CT imaging

“…A retrospective study by Giesel et al ( 20 ) showed that 18 F-PSMA-1007 had a higher detection rate of biochemical recurrence than 68 Ga-PSMA-11, even in patients with low PSA levels (≤0.5 ng/mL) in patients. In addition, 18 F-PSMA-1007 also showed higher sensitivity to low-grade lesions ( 21 ). These findings suggest that 18 F-PSMA-1007 may have a significant impact on the further management of the disease.…”

“…In addition to this, 18 F-PSMA-1007 is mainly metabolized by the liver and temporarily stored in the renal parenchyma, but endocrine therapy, chemotherapy and other drugs in prostate cancer patients may cause injury to liver and kidney function. It has also been shown that renal 18 F-PSMA-1007 uptake parameters correlate with EGFR and can indicate renal cortical function ( 21 ). However, high 18 F-PSMA-1007 uptake in the bladder cannot be linked to liver and kidney function, as no significant differences were found by analyzing different treatment methods as well as liver and kidney function indicators of the patients.…”

A Comparison of 68Ga-PSMA PET/CT-Based Split Renal Function with 99mTc-MAG3 Renography in Patients with Metastatic Castration-Resistant Prostate Carcinoma Treated with 177Lu-PSMA

“…The higher spatial resolution of PET/CT allowed for the detection of small cysts that were not visualised on 99m Tc-DMSA SPECT and correctly identified false positive findings on SPECT due to cortical thinning [ 31 ], potentially offering a non-invasive alternative or complimentary investigation to 99m TcMAG3 renal scintigraphy. Several studies have shown that renal 68 Ga-PSMA can reliably measure approximate renal parenchymal volume and cortical uptake correlates with renal function tests such as GFR and creatinine [ 33 , 34 , 35 ]. This is especially beneficial in cases where 99m Tc-MAG3 imaging may not be feasible, such as during Molybdenum-99 shortages [ 36 ], or when patient logistics preclude an additional study.…”

Dependence of Renal Uptake on Kidney Function in [68Ga]Ga-PSMA-11 PET/CT Imaging

“…On the other hand, PET tracers such as somatostatin receptor analogs have been suggested as potential signs of renal dysfunction [17,18]. Furthermore, comparisons between PSMA ligand uptake of different radiopharmaceuticals and estimated GFR (eGFR) have been performed, with divergent results [19][20][21] Even though PET/CT imaging is primarily used to detect tumors and inflammation, tissue characterization and information about its dependence on physiological processes can be advantageous for gaining insight into other diseases. [ 68 Ga]Ga-PSMA-11 is a widely used radiopharmaceutical for PSMA ligand PET/CT imaging and was recently approved by the U.S. Food and Drug Administration and the European Medicines Agency [22].…”