It is well established that [68Ga]Ga-prostate-specific membrane antigen-11 ([68Ga]Ga-PSMA-11) PET/CT offers greater diagnostic precision than [18F]F-Fluorocholine PET/CT for prostate cancer (PCa). Nevertheless, whether this improved accuracy translates into better clinical outcomes in oligometastatic PCa patients managed with [68Ga]Ga-PSMA-11 PET-guided metastasis-directed therapy (MDT) remains unclear. This investigation evaluated the effects of the two imaging modalities on Progression-Free Survival (PFS) in a real-world cohort of oligometastatic PCa patients who received PET-guided MDT. A total of 37 patients were included retrospectively. In eleven cases, MDT was guided by [18F]F-Fluorocholine PET/CT, while [68Ga]Ga-PSMA-11 PET/CT was used in twenty-six. Progression was defined according to biochemical recurrence (BR), new radiological findings on follow-up PET/CT, clinical deterioration, start of androgen deprivation therapy, or death. Various clinical and imaging factors were analyzed as potential predictors of PFS. Patients whose MDT was guided by [18F]F-Fluorocholine PET/CT experienced markedly shorter PFS compared with the [68Ga]Ga-PSMA-11 group (median PFS 15.47 months, 95% CI: 4.13–38.00 versus 40.93 months, 95% CI: 40.93–40.93; P < 0.05). Correspondingly, the choice of radiotracer for PET-guided MDT emerged as a predictor of PFS on univariate analysis, along with castration-resistant status at the time of MDT and PSA nadir following MDT. On multivariate analysis, however, only castration resistance and post-MDT PSA nadir remained independent predictors of PFS. In summary, this preliminary proof-of-concept study found that [68Ga]Ga-PSMA-11 imaging was linked to superior PFS rates relative to [18F]F-Fluorocholine in oligometastatic PCa patients treated with PET-guided MDT. Although these results are initial, they indicate that expanding detection of disease extent through next-generation imaging—thereby identifying a larger share of otherwise hidden lesions—may improve oncological outcomes when MDT is applied in oligometastatic PCa.
