Head-to-head comparison of ⁶⁸Ga-PSMA-11 PET/CT and ¹⁸F-Fluciclovine PET/CT in a case series of 10 patients with prostate cancer recurrence

Abstract

Purpose: This is a head-to-head comparison between Gallium-68 Prostate Specific Membrane Antigen (⁶⁸Ga-PSMA-11) and ¹⁸F-Fluciclovine Positron Emission Tomography/Computed Tomography (PET/CT) in a series of 10 patients with prostate cancer (PCa) recurrence. Methods: 288 patients with PCa recurrence were enrolled in a prospective study of ⁶⁸Ga-PSMA-11 PET/CT imaging for recurrent disease localization (NCT02940262). We retrospectively identified 10 patients who underwent clinical indicated ¹⁸F-Fluciclovine PET/CT prior enrollment. Results: The median time between both scans was 2.3 months (range 0.2-4.2). The median PSA value was 1.0 ng/ml (mean 4.7 ng/ml; range 0.13-18.1) and 1.1 ng/ml (mean 6.2 ng/ml; range 0.24-31.3) at the time of ¹⁸F-Fluciclovine and ⁶⁸Ga-PSMA-11 PET/CT, respectively. 5/10 patients (50%) were negative on ¹⁸F-Fluciclovine PET/CT but showed positive results on ⁶⁸Ga-PSMA-11 PET/CT. 2/10 patients (20%) had both positive ¹⁸F-Fluciclovine and ⁶⁸Ga-PSMA-11 PET/CT but ⁶⁸Ga-PSMA-11 PET/CT showed additional lymph nodes (LN) metastasis. 3/10 patients (30%) had both negative ¹⁸F-Fluciclovine and ⁶⁸Ga-PSMA-11 PET/CT. Conclusion: This case series suggests superior detection rate of ⁶⁸Ga-PSMA-11 PET/CT than ¹⁸F-Fluciclovine PET/CT in recurrent PCa. Prospective trials designed to directly compare ⁶⁸Ga-PSMA-11 and ¹⁸F-Fluciclovine PET/CT should be initiated.