Cohort Study of Oligorecurrent Prostate Cancer Patients: Oncological Outcomes of Patients Treated with Salvage Lymph Node Dissection via Prostate-specific Membrane Antigen–radioguided Surgery

Background: In a subset of patients with recurrent oligometastatic prostate cancer (PCa) salvage surgery with prostate-specific membrane antigen (PSMA)-targeted radioguidance (PSMA-RGS) might be of value. Objective: To evaluate the oncological outcomes of salvage PSMA-RGS and determine the predictive preoperative factors of improved outcomes. Design, setting, and participants: A cohort study of oligorecurrent PCa patients with biochemical recurrence (BCR) after radical prostatectomy and imaging with PSMA positron emission tomography (PET), treated with PSMA-RGS in two tertiary care centers (2014–2020), was conducted. Intervention: PSMA-RGS. Outcome measurements and statistical analysis: Kaplan-Meier and multivariable Cox regression models were used to assess BCR-free (BFS) and therapy-free (TFS) survival. Postoperative complications were classified according to Clavien-Dindo. Results and limitations: Overall, 364 patients without concomitant treatment were assessed. At PSMA-RGS, metastatic soft-tissue PCa lesions were removed in 343 (94%) patients. At 2–16 wk after PSMA-RGS, 165 patients reached a prostate-specific antigen (PSA) level of <0.2 ng/ml. Within 3 mo, 24 (6.6%) patients suffered from Clavien-Dindo complications grade III–IV. At 2 yr, BFS and TFS rates were 32% and 58%, respectively. In multivariable analyses, higher preoperative PSA (hazard ratio [HR]: 1.07, 95% confidence interval [CI]: 1.02–1.12), higher number of PSMA-avid lesions (HR: 1.23, CI: 1.08–1.40), multiple (pelvic plus retroperitoneal) localizations (HR: 1.90, CI: 1.23–2.95), and retroperitoneal localization (HR: 2.04, CI: 1.31–3.18) of lesions in preoperative imaging were independent predictors of BCR after PSMA-RGS. The main limitation is the lack of a control group. Conclusions: As salvage surgery in oligorecurrent PCa currently constitutes an experimental treatment approach, careful patient selection is mandatory based on life expectancy, low PSA values, and low number of PSMA PET–avid lesions located in the pelvis. Patient summary: We looked at the outcomes from prostate cancer patients with recurrent disease after radical prostatectomy. We found that surgery may be an opportunity to prolong treatment-free survival, but patient selection criteria need to be very narrow.