Robot-assisted PSMA-radioguided Surgery to Assess Surgical Margins and Nodal Metastases in Prostate Cancer Patients: Report on Three Cases Using an Intraoperative PET-CT Specimen Imager

Introduction: The aim of this feasibility study was to test the intraoperative use of this brand-new specimen PET/CT to guide robot-assisted radical prostatectomy and pelvic lymph node dissection. Materials and methods: Three cases of robot-assisted radical prostatectomy and pelvic lymph node dissection were performed with intraoperative use of the specimen imager. Surgeries were performed with Da Vinci Xi robot. An intravenous injection of 68Ga-PSMA-11 was performed in the OR and after complete excision, the specimens were analyzed with the imager. Results: The average nodal yield was 17.3 (5.8 SD) nodes per patient. Specimen PET/CT images showed a focal uptake in a metastatic node (TBR 13.6), and no uptake or diffuse, faint uptake in negative nodes (TBR range: 1-5.3). The specimen imager provided intraoperative PET/CT images that clearly showed negative surgical margins in two patients, whereas the results were uncertain in a locally advanced case. Conclusion: The intraoperative use of the specimen PET/CT imager is safe and feasible and could improve the evaluation of prostate surgical margins and lymph node status.