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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 evaluate longer‐term oncological and functional outcomes of focal irreversible electroporation (IRE) as primary treatment for localised clinically significant prostate cancer (csPCa) at a median follow‐up of 5 years (up to 10 years). Patients and Methods All patients that underwent focal IRE as primary treatment for localised PCa between February 2013 and August 2021 with a minimum 12 months of follow‐up were analysed. Follow‐up included 6‐month magnetic resonance imaging (MRI) and standardised transperineal saturation template ± targeted biopsies at 12 months, and further biopsies in the case of clinical suspicion on serial imaging and/or prostate‐specific antigen (PSA) levels. Failure‐free survival (FFS) was defined as no progression to radical treatment or nodal/distant disease. Local recurrence was defined as any International Society of Urological Pathology Grade of ≥2 on biopsy. Results A total of 229 patients were analysed with a median (interquartile range [IQR]) follow‐up of 60 (40–80) months. The median (IQR) age was 68 (64–74) years, the median (IQR) PSA level was 5.9 (4.1–8.2) ng/mL, and 86% harboured intermediate‐risk disease and 7% high‐risk disease. In all, 38 patients progressed to radical treatment (17%), at a median (IQR) of 35 (17–53) months after IRE. Kaplan–Meier FFS rates were 91% at 3 years, 84% at 5 years and 69% at 8 years. Metastasis‐free survival was 99.6% (228/229), PCa‐specific and overall survival were 100% (229/229). Residual csPCa was found in 24% (45/190) during follow‐up biopsy and MRI showed a complete ablation in 82% (186/226). Short‐term urinary continence was preserved (98%, three of 144 at baseline, 99%, one of 131 at 12 months) and erections sufficient for intercourse decreased by 13% compared to baseline (71% to 58%). Conclusion Longer‐term follow‐up confirms our earlier findings that focal IRE provides acceptable local and distant oncological control in selected men with less urinary and sexual toxicity than radical treatment. Long‐term follow‐up and external validation of these findings, is required to establish this new treatment paradigm as a valid treatment option.