The value of ¹⁸F-PSMA-1007 PET/CT in identifying non-metastatic high-risk prostate cancer

Clinical management decisions on prostate cancer (PCa) are often based on a determination of risk. ⁶⁸Ga-prostate-specific membrane antigen (PSMA)-11-positron emission tomography (PET)/computer tomography (CT) is an attractive modality to assess biochemical recurrence of PCa, detect metastatic disease and stage of primary PCa, making it a promising strategy for risk stratification. However, due to some limitation of ⁶⁸Ga-PSMA-11 the development of alternative tracers is of high interest. In this study, we aimed to investigate the value of ¹⁸F-PSMA-1007 in identifying non-metastatic high-risk PCa.

A total of 101 patients with primary non-metastatic PCa who underwent ¹⁸F-PSMA-1007 PET/CT were retrospectively analyzed. According to the European Association of Urology guidelines on PCa, patients were classified into intermediate-risk (IR) group or high-risk (HR) group. The maximum standardized uptake values (SUVmax) of the primary prostate tumor were measured on PET/CT images. The diagnostic performance of PET/CT for IR and HR PCa was calculated, and the relationship between the SUVmax of primary prostate tumor, prostate-specific antigen (PSA) level and Gleason score (GS) was analyzed.

Of all 101 patients, 49 patients were classified into IR group and 52 patients were classified into HR group. There was a significant positive correlation between PSA level/GS and SUVmax (r = 0.561, r = 0.496, P < 0.001, respectively). Tumors with GS 6 and 7a showed significantly lower ¹⁸F-PSMA-1007 uptake compared to patients with GS 8 and 9 (P < 0.01). SUVmax in patients of HR was significantly higher than those of IR (median SUVmax: 16.85 vs 7.80; P < 0.001). In receiver operating characteristic curve analysis, the optimal cutoff value of the SUVmax for identifying high-risk PCa was set as 9.05 (area under the curve: 0.829; sensitivity: 90.4%; specificity: 65.3%).

¹⁸F-PSMA-1007 PET/CT showed the powerful diagnosis efficacy for high-risk PCa, which can be used as an objective imaging reference index for clinical reference.