Higher Preoperative Maximum Standardised Uptake Values (SUV_max) Are Associated with Higher Biochemical Recurrence...

This study aimed to investigate the association between the ⁶⁸Ga- or ¹⁸F-radiolabeled prostate-specific membrane antigen (PSMA) tracer expression, represented by the maximum standardised uptake value (SUV_max) of the dominant intraprostatic lesion, and biochemical recurrence (BCR) in primary prostate cancer (PCa) patients prior to robot-assisted radical prostatectomy (RARP). This was a retrospective, multi-centre cohort study of 446 patients who underwent [⁶⁸Ga]Ga-PSMA-11 (n = 238) or [¹⁸F]DCFPyL (n = 206) Positron Emission Tomography/Computed Tomography (PET/CT) imaging prior to RARP. SUV_max was measured in the dominant intraprostatic PCa lesions. [¹⁸F]DCFPyL patients were scanned 60 ([¹⁸F]DCFPyL-60; n = 106) or 120 ([¹⁸F]DCFPyL-120; n = 120) minutes post-injection of a radiotracer and were analysed separately. To normalise the data, SUV_max was log transformed for further analyses. During a median follow-up of 24 months, 141 (30.4%) patients experienced BCR. Log₂SUV_max was a significant predictor for BCR (p < 0.001). In the multivariable analysis accounting for these preoperative variables: initial prostate-specific antigen (PSA), radiologic tumour stage (mT), the biopsy International Society of Urological Pathology grade group (bISUP) and the prostate imaging and reporting data system (PI-RADS), Log₂SUV_max was found to be an independent predictor for BCR in [⁶⁸Ga]Ga-PSMA-11 (HR 1.32, p = 0.04) and [¹⁸F]DCFPyL-120 PET/CT scans (HR 1.55, p = 0.04), but not in [¹⁸F]DCFPyL-60 ones (HR 0.92, p = 0.72). The PSMA expression of the dominant intraprostatic lesion proved to be an independent predictor for BCR in patients with primary PCa who underwent [⁶⁸Ga]Ga-PSMA-11 or [¹⁸F]DCFPyL-120 PET/CT scans, but not in those who underwent [¹⁸F]DCFPyL-60 PET/CT scans.