Cyclotron vs generator-produced 68Ga PSMA: a single-institution, prospective clinical trial

The clinical utility of gallium 68 (⁶⁸Ga)-PSMA PET for the diagnosis and management of prostate cancer is driven in part by radioisotope availability and production costs. This study evaluates the equivalence between the two manufacturing processes for ⁶⁸Ga-PSMA: ⁶⁸Ga-PSMA-cyclotron (from a solid target) and ⁶⁸Ga-PSMA-generator. A prospective, single-arm, single-institution non-randomized study was conducted where 16 patients with prostate adenocarcinoma underwent PET/CTs consecutively within 12 to 48 hours with each type of manufactured ⁶⁸Ga-PSMA between December 2020 and June 2021. The intraclass correlation coefficients suggested acceptable reliability in all lesion parameters (ICC > 0.70). Bland-Altman analysis demonstrated acceptable bias levels for all lesion parameters. Thereby ⁶⁸Ga-cyclotron (solid target) and ⁶⁸Ga-generator production methods tagged to the same PSMA ligand resulted in scans which were deemed to be equivalent in detecting PSMA+ lesions in our study. As cyclotron-produced, solid- target ⁶⁸Ga can be made in large (Ci) quantities, it is a promising tool for future application in ⁶⁸Ga-PSMA PET scans with the potential to decrease radiotracer production costs and increase isotope availability.