The Prognostic Role of Preoperative PSMA PET/CT in cN0M0 pN+ Prostate Cancer: A Multicenter Study

Despite negative preoperative conventional imaging, up to 10% of patients with prostate cancer (PCa) harbor lymph-node involvement (LNI) at radical prostatectomy (RP). The advent of more accurate imaging modalities such as PET/CT improved the detection of LNI. However, their clinical impact and prognostic value are still unclear. We aimed to investigate the prognostic value of preoperative PET/CT in patients node positive (pN+) at RP. We retrospectively identified cN0M0 patients at conventional imaging (CT and/or MRI, and bone scan) who had pN+ PCa at RP at 17 referral centers. Patients with cN+ at PSMA/Choline PET/CT but cN0M0 at conventional imaging were also included. Systemic progression/recurrence was the primary outcome; Cox proportional hazards models were used for multivariate analysis. We included 1163 pN+ men out of whom 95 and 100 had preoperative PSMA and/or Choline PET/CT, respectively. ISUP grade ≥4 was detected in 66.6%. Overall, 42% of patients had postoperative PSA persistence (≥0.1 ng/mL). Postoperative management included initial observation (34%), ADT (22.7%) and adjuvant RT+/-ADT (42.8%). Median follow-up was 42 months. Patients with cN+ on PSMA PET/CT had an increased risk of systemic progression (52.9% vs. 13.6% cN0 PSMA PET/CT vs. 21.5% cN0 at conventional imaging; P < .01). This held true at multivariable analysis: (HR 6.184, 95% CI: 3.386-11-295; P < .001) whilst no significant results were highlighted for Choline PET/CT. No significant associations for both PET types were found for local progression, BCR, and overall mortality (all P > .05). Observation as an initial management strategy instead of adjuvant treatments was related with an increased risk of metastases (HR 1.808; 95% CI: 1.069-3.058; P < .05). PSMA PET/CT cN+ patients with negative conventional imaging have an increased risk of systemic progression after RP compared to their counterparts with cN0M0 disease both at conventional and/or molecular imaging. PET/CT have improved the detection of lymph node involvement in patients with prostate cancer at staging. We aimed to investigate the prognostic value of preoperative PET/CT in patients with node negative at conventional imaging and node positive at radical prostatectomy (RP). We included 1163 patients with these features from 17 referral centers. 95 and 100 patients had preoperative PSMA and/or Choline PET/CT, respectively. Node positive patients at PSMA PET/CT with negative conventional imaging have an increased risk