[¹⁸F]PSMA-1007 PET is comparable to [^99mTc]Tc-DMSA SPECT for renal cortical imaging

Area of Science:

• Nuclear medicine
• Radiopharmaceutical imaging
• Prostate cancer diagnostics

Background:

• Technetium-99m labelled dimercaptosuccinic acid (DMSA) scintigraphy with SPECT is standard for renal cortex functional imaging.
• Prostate-specific membrane antigen (PSMA) PET is used in prostate cancer staging and recurrence detection, showing high renal uptake.
• [18F]PSMA-1007 PET offers potential for renal cortical imaging due to low urinary clearance.

Purpose of the Study:

• To compare [18F]PSMA-1007 PET with [99mTc]Tc-DMSA SPECT for renal cortical imaging in prostate cancer patients.
• To evaluate the detection of split renal uptake and renal uptake defects using both imaging modalities.
• To assess the correlation of split renal function measurements between [18F]PSMA-1007 PET and [99mTc]Tc-DMSA SPECT.

Main Methods:

• Twenty prostate cancer patients underwent both [18F]PSMA-1007 PET and [99mTc]Tc-DMSA SPECT.
• Three readers assessed images for renal uptake defects in cranial, mid, and caudal kidney segments.
• Split renal uptake was quantified by measuring left renal uptake as a percentage of total renal uptake.

Main Results:

• A total of 29 defects were identified on both [18F]PSMA-1007 PET and [99mTc]Tc-DMSA SPECT scans.
• Concordance for defect presence was substantial (Cohen's kappa 0.76 per segment, 0.67 per kidney).
• Split renal uptake measurements showed strong correlation (Spearman's r = 0.95) between the two methods.

Conclusions:

• [18F]PSMA-1007 PET is a comparable alternative to [99mTc]Tc-DMSA SPECT for detecting renal cortical uptake defects.
• Split renal function measurements using [18F]PSMA-1007 PET are valid and highly correlated with [99mTc]Tc-DMSA SPECT.
• PSMA PET shows promise for functional renal imaging in prostate cancer patients.