ObjectivesTo evaluate the safety and feasibility of 99m Tc-based prostate-specific membrane antigen (PSMA) robot-assisted radioguided surgery to aid or improve the intraoperative detection of lymph node metastases during primary robot-assisted radical prostatectomy (RARP) for prostate cancer (PCa). Materials and MethodsMen with primary high-risk Pca (≥cT3a, international society of urological pathology (ISUP) Grade Group ≥3 or PSA of ≥ 15 ng/mL) with potential lymph node metastasis (Briganti nomogram risk >10% or on preoperative imaging) were enrolled onto the study. Patients underwent a staging 68 Ga-PSMA PET/CT. Pre-operatively a 99m Tc-labelled PSMA ligand ( 99m Tc PSMA I&S; 500 MBq) was administrated followed by single-photon emission/CT(SPECT). A RARP including extended pelvic lymph node dissection was performed, with intraoperative tracing of PSMA-avid tissues using a prototype DROP-IN gamma probe. Resected specimens were also measured ex-vivo. Histopathological concordance with probe findings was evaluated. A radiotracer count of ≥ 1.5 times the background reference (invivo), and ≥10 (absolute count) in the ex-vivo setting, was considered positive. ResultsTwelve patients were included, median age of 68 years and PSA of 9.15 ng/ml. The majority of patients harboured ISUP 5 PCa (75%) and had avid lymph nodes on pre-operative PSMA PET (64%). The DROP-IN probe aided resection of PSMA-avid (out-of-template) lymph nodes and residual disease at the prostate bed. 11 metastatic lymph nodes were identified by the probe that were not observed on pre-operative 68 Ga-PSMA PET/CT. Of the 74 extraprostatic tissue specimens that were resected, 22 (29.7%) contained PCa. The sensitivity, specificity, PPV and NPV (95% confidence interval) of inpatient use of the gamma probe was 76% (53-92%), 69% (55-81%), 50% and 88%, respectively. Ex-vivo, the diagnostic accuracy was superior, 76% (53-92%), 96% (87-99%), 89% and 91%, respectively. Of the missed lymph nodes in-vivo (n=5) and ex-vivo (n=5), 90% were micrometastasis (≤3mm). No complications occurred greater than Clavien-Dindo Grade I. ConclusionRobot-assisted 99mTc-based PSMA radioguided surgery is feasible and safe in the primary setting, optimizing the detection of nodal metastases at the time of RARP and ePLND. Further improvement of the detector technology may optimize the capabilities of robot-assisted 99m Tc-based PSMA-radioguided surgery.

Objectives To prospectively assess the safety, functional‐ and oncological‐outcomes of irreversible electroporation (IRE) as salvage therapy for radio‐recurrent focal prostate cancer in a multicenter setting. Patients and methods Men with focal recurrent PCa after external beam radiation or brachytherapy without metastatic disease on staging imaging and co‐registration between mpMRI and biopsies were prospectively included in this multicenter trial. Adverse events were reported following the Clavien‐Dindo classification. Validated questionnaires were used for patient‐reported functional outcomes. Follow‐up consisted of 3 monthly prostate specific antigen (PSA) levels, a 6‐month mpMRI and standardised transperineal template mapping biopsies at 12‐months. Thereafter follow‐up was guided by MRI and/or PSMA‐PET/CT and PSA. Local recurrence was defined as any ISUP score ≥2 on biopsies. Results 37 patients were analysed with a median (interquartile range (IQR)) follow up of 29 (22–43) months. Median age was 71 (53–83), median PSA was 3.5 ng/mL (2.7–6.1). 28 (75.5%) patients harboured intermediate risk and 9 patients (24.5%) high risk PCa. Seven patients (19%) reported self‐limiting urgency, frequency, or hematuria (grade 1–2). Seven patients (19%) developed a grade 3 AE; urethral sludge requiring transurethral resection. At 12 months post treatment 93% of patients remained continent and erectile function sufficient for intercourse deteriorated from 35% to 15% (4/27). Local control was achieved in 29 patients (78%) and 27 patients (73%) were clear of local and systemic disease. Four (11%) patients had local recurrence only. Six (16%) patients developed metastatic disease with a median time to metastasis of 8 months. Conclusion The FIRE trial shows that salvage IRE after failed radiation therapy for localised PCa is safe with minimal toxicity, and promising functional and oncological outcomes. Salvage IRE can offer a possible solution for notoriously difficult to manage radio recurrent prostate tumours.

Background To report the feasibility, oncological and functional outcomes of salvage robot-assisted radical prostatectomy (sRARP) for recurrent prostate cancer (PCa) after irreversible electroporation (IRE). Methods This was a retrospective analysis of patients who underwent sRARP by a single high-volume surgeon after IRE treatment in our institution. Surgical complications, oncological and functional outcomes were assessed. Results 15 patients with at least 12 months follow up were identified out of the 234 men who underwent primary IRE between 2013 and 2019. The median [IQR] age was 68 (62–70) years. The median [IQR] time from focal IRE to sRARP was 42 (21–57) months. There were no rectal, bladder or ureteric injuries. The T-stage was pT2 in 9 (60%) patients and pT3a in 6 (40%) patients. Only one (7%) patient had a positive surgical margin. At a median [IQR] follow up of 22 (16–32) months no patient had a biochemical recurrence (PSA > 0.2). All 15 patients were continent (pad-free) by 6 months and 9 (60%) patients had erections sufficient for intercourse with or without PDE5 inhibitors. No predisposing factors were identified for predicting erectile dysfunction after sRARP. Conclusions In patients with recurrent or residual significant PCa after focal IRE ablation it is feasible to obtain good functional and oncological outcomes with sRARP. Our results demonstrate that good outcomes can be achieved with sRARP, when respecting close monitoring post-IRE, good patient selection and surgical experience. The limitations of this study are that it is a small series, with short follow up and a lack of standardised quality of life instruments.