NCT07272317

PSMA-PET/MRI-Ultrasound Multimodal Fusion Navigation for Da Vinci Robot-Assisted Radical Prostatectomy: A Randomized Controlled Trial

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 98 (estimated)
• Sponsor: Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine · Academic / Other
• Sex: Male
• Age: 90 Years
• Healthy volunteers: Not accepted

Summary

Radical prostatectomy faces the core dilemma of balancing functional preservation with tumor eradication. While nerve-sparing techniques improve urinary control, intraoperative tumor localization remains imprecise, resulting in positive surgical margin (PSM) rates of 11%-38% and elevated recurrence risk. Traditional preoperative 2D imaging fails to dynamically guide surgical boundaries. Although multimodal fusion studies (e.g., MRI or PSMA-PET/CT) attempt to address this, they struggle to achieve simultaneous precision in lesion identification and real-time spatial tracking. This study pioneers a PSMA-PET/MRI-ultrasound multimodal fusion navigation system for the Da Vinci surgical robot, leveraging three innovations: PSMA-PET/MRI dual-modality synergy for subclinical lesion detection at millimeter resolution; Non-rigid point-cloud registration algorithms to dynamically compensate for intraoperative prostate deformation, enabling 3D ultrasound-PET/MRI elastic fusion; Utilizing the telipro port of the Da Vinci surgical robot to achieve intraoperative picture-in-picture navigation, real-time localization of the tumor boundary, and precise resection as well as precise protection.This study aims to verify the safety and effectiveness of the world's first PSMA-PET/MRI-ultrasound multimodal fusion navigation system adapted for the Da Vinci surgical robot. This system is expected to reduce the positive margin rate to less than 10%, increase the rate of nerve preservation by 30%, shorten the postoperative urinary control recovery time to within 2 weeks, and establish a standard process for robotic surgery navigation. This will provide a new paradigm for precise surgical treatment of prostate cancer.

Detailed description

Prostate cancer, the second most prevalent malignancy in men globally, has long grappled with a core dilemma in radical surgery: balancing functional preservation against oncological efficacy. Although nerve-sparing techniques significantly improve postoperative urinary control and sexual function (with robotic surgery achieving \>80% continence recovery rates), conventional approaches relying on intraoperative visual tumor boundary assessment result in positive surgical margin (PSM) rates of 11%- 38%, increasing biochemical recurrence risk exceeding 40% \[1,2\]. For locally advanced cases, sacrificing functional structures to ensure oncological radicality leads to postoperative erectile dysfunction rates up to 95% and urinary incontinence exceeding 50% \[3\].The essence of this conflict lies in: Extended resection reduces PSM rates but damages neurovascular bundles (NVBs) governing micturition and erectile function; Limited resection preserves function yet increases PSM risk due to residual microlesions-particularly in anatomically complex zones like the prostatic apex and anterior wall, where visual localization errors typically exceed 3 mm. Preoperative imaging limitations exacerbate this: MRI offers high anatomical resolution (0.5 mm³) but cannot track intraoperative organ deformation; PSMA-PET/CT detects micrometastases with 98% sensitivity, yet spatial registration errors between metabolic/anatomical data exceed 2 mm \[4\]. Current multimodal fusion approaches are inadequate: MRI-based fusion misses early-stage lesions due to limited tumor contrast; PSMA-PET/CT fusion suffers from metabolic-anatomical misalignment. Thus, a navigation system enabling simultaneous subclinical lesion detection and dynamic deformation compensation is imperative to resolve the function-versus-curability dilemma. We have adopted the following approaches to complete the construction of the intraoperative navigation system: (1) On the PET/MRI before the operation, the prostate and the lesion were delineated: at least two nuclear medicine physicians independently reviewed the images and then provided a unified report; the external contour of the prostate and the three-dimensional lesion schematic diagram of the lesion were then delineated by a urologist; (2) On the intraoperative ultrasound, the prostate was delineated: the prostate image was captured in real time by BK ultrasound and then the external contour of the prostate was delineated by a urologist; (3) The multimodal fusion of the three-dimensional lesion delineated by BK ultrasound and PSMAPET/MRI was achieved through the MIM software built into the BK ultrasound; (4) The intraoperative resection was guided by the Da Vinci Tilepro functional module. So far, 6 cases have been successfully completed and compared with 6 T3a patients randomly selected from previous conventional surgeries. Currently, due to the small sample size, although the differences in the surgical margins have not reached a statistically significant difference, a trend of difference has been demonstrated. Due to the short follow-up period, the postoperative PSA and urination conditionshave not been included in the statistical cohort.

Conditions

• Prostate Cancer

Interventions

Type	Name	Description
PROCEDURE	experimental group (navigation-assisted RARP)	Before the surgery, the prostate and lesions were delineated on PET/MRI: at least two nuclear medicine physicians independently reviewed the images and provided a unified report. The experimental group had the external contour of the prostate and the three-dimensional lesion schematic diagram delineated by the urologist. A BK5000 ultrasound probe was inserted into the rectum, the probe was fixed to the surgical bed frame by the stepper, and the real-time images of the prostate were captured by the ultrasound.The multimodal fusion of the three-dimensional lesion outlined by ultrasound and PSMA-PET/MRI was achieved through the built-in MIM software. Subsequently, picture-in-picture guidance was realized through the Da Vinci Tilepro functional module, and the edge of the lesion was marked with titanium clips. After the ultrasound probe was withdrawn, the peripheral resection of the prostate, nerve preserve or not were completed under the guidance of the titanium clips.

Timeline

• Start date: 2025-12-15
• Primary completion: 2026-06-30
• Completion: 2026-12-30
• First posted: 2025-12-09
• Last updated: 2025-12-09

Locations

1 site across 1 country: China