Head-to-Head Comparison of 68 Ga-P16-093 and 68 Ga-PSMA-617 PET/CT in Patients With Primary Prostate Cancer : A Pilot Study.

Objective: We aimed to compare the diagnostic performance of 68 Ga-P16-093 and 68 Ga-PSMA-617 PET/CT in primary prostate cancer (PCa) patients.

Methods: Thirty untreated primary PCa patients were enrolled. Each patient underwent 68 Ga-P16-093 and 68 Ga-PSMA-617 PET/CT within a week. In addition to visual analysis, SUV was measured for semiquantitative comparison and correlation analysis.

Results: 68 Ga-P16-093 PET/CT detected more positive tumors than 68 Ga-PSMA-617 PET/CT (67 vs 56, P = 0.002), especially for intraprostatic lesions (29 vs 24, P = 0.025) and lymph node metastases (23 vs 17, P = 0.034). Further, 68 Ga-P16-093 PET/CT exhibited significantly higher SUV max of matched tumors (18.3 ± 14.4 vs 13.9 ± 11.8, P < 0.001). Besides, the SUV max of high-risk patients (based on D'Amico classification) on 68 Ga-P16-093 PET/CT was significantly higher than that of low- and intermediate-risk PCa patients (20.9 ± 9.9 vs 8.9 ± 9.1 vs 10.1 ± 5.2, P = 0.007). The SUV max of tumor measured by 68 Ga-P16-093 PET/CT had a moderate association with biopsy Gleason score ( r = 0.462, P = 0.005) and prostate-specific antigen value ( r = 0.491, P = 0.002), and significantly correlated with PSMA expression ( r = 0.732, P < 0.001).

Conclusions: 68 Ga-P16-093 PET/CT exhibited higher tumor uptake and potentially better tumor detection capability than 68 Ga-PSMA-617 PET/CT, which suggested that 68 Ga-P16-093 may be more suitable in the diagnosis and staging of primary PCa patients.