Augmented Reality PSMA-3D guided robotic pelvic lymph node dissection (PLND) in prostate cancer patients

Area of Science:

• Urology
• Oncology
• Medical Imaging

Background:

• Accurate intraoperative identification of lymph node metastases (LNM) during robot-assisted radical prostatectomy (RARP) with pelvic lymph node dissection (PLND) is crucial for optimal surgical outcomes in prostate cancer (PCa) patients.
• Preoperative PSMA-PET imaging is vital for detecting LNM, but real-time intraoperative guidance for precise dissection remains a challenge.

Purpose of the Study:

• To describe and evaluate a novel augmented reality (AR)-PSMA-3D guided PLND technique.
• To assess the feasibility of real-time intraoperative identification and resection of suspicious LNM detected by PSMA-PET during RARP.

Main Methods:

• Prospective enrollment of thirteen high-risk PCa patients with suspected lymph node metastases (miN1-2 or miM1a) at PSMA-PET.
• Creation of a 3D segmentation model of suspicious LNM from preoperative PSMA-PET images.
• Performance of RARP with AR-PSMA-3D guided PLND for real-time intraoperative guidance, with pathologic examination as the reference standard.

Main Results:

• AR-PSMA-3D guided PLND successfully facilitated the dissection of suspicious LNM, including four cases (30%) outside the standard PLND template, without intraoperative complications.
• Pathologic examination confirmed pN1 disease in nine patients (69%), with three (23%) having metastases outside the PLND template.
• Per-region analysis demonstrated high performance for AR-PSMA-3D guided PLND, with sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of 69%, 90%, 52%, 95%, and 0.79, respectively.

Conclusions:

• AR-PSMA-3D guidance for PLND is a promising technique for facilitating the resection of suspicious LNM in PCa patients with PSMA-PET detected metastases, including those outside the conventional PLND template.
• The technique enables real-time identification of suspicious nodes, potentially improving surgical precision.
• Limitations include the spatial resolution of PSMA-PET for micro-metastases and the need for manual alignment of the 3D model.