3D VR models help improve outcomes for patients undergoing robotic prostatectomy

Patients whose surgical planning for robotic-assisted laparoscopic radical prostatectomy (RALP) involved 3-dimensional (3D) virtual reality (VR) models experience better oncologic outcomes without compromising functional outcomes, reports a recent study.

“In patients undergoing RALP, the use of 3D VR models for operative planning improved oncologic outcome while maintaining functional outcomes,” said the researchers, led by Joseph D. Shirk of the UCLA Department of Urology, Los Angeles, California, US.

Shirk and his team conducted a multicentre, randomized, single-blind clinical trial from January 2019 to December 2020. They prospectively enrolled and randomly assigned 92 patients undergoing RALP to either an intervention group where magnetic resonance imaging (MRI) and biopsy results were supplemented with a 3D VR model or a control group undergoing usual preoperative planning with prostate biopsy results and MRI only.

No significant difference was observed in functional outcomes and traditional operative metrics (p>0.05), but trends toward lower positive margin rates in the intervention group (33 percent vs 25 percent) were noted. The intervention group also had significantly lower detectable postoperative prostate-specific antigen (PSA; 31 percent vs 9 percent; p=0.036). [J Urol 2022;208:618-625]

Notably, surgeons adjusted their operative plan based on the model in 32 percent of patients in the intervention arm. Comparing this cohort to the control group, a robust trend was noticed toward increased bilateral nerve sparing (78 percent vs 92 percent). Additionally, there was a significantly lower rate of postoperative detectable PSA in the intervention subset (31 percent vs 0 percent; p=0.038).

Improved outcomes

“For patients undergoing RALP, we identified improvements in key postoperative metrics that define oncologic outcomes,” the researchers said.

Better oncologic outcomes are characterized by lower positive margin rates and postoperative PSA. Patients with either positive margins or early detectable PSA are significantly more likely to progress to more advanced disease and need future treatment, such as radiation or androgen deprivation therapy. [Eur Urol 2019;76:106-114; World J Urol 2018;36:1803-1815]

“While we did not see a significant difference in margin status, the difference noted in postoperative PSA may be due to varying degrees of margin positivity,” the researchers said.

“As we only defined margins as positive or negative, the degree of positivity may have been less in the intervention cases, and potentially not clinically significant, as a result of the decisions made after review of the 3D model,” they added. [Eur Urol Oncol 2021;4:42-48]

Implications

These findings can markedly influence patient care. For instance, the surgeon can counsel patients more directly in terms of projected trifecta outcomes during the planning stage. Such action may result in treatment selection that agrees with patient preferences and appropriate patient expectations.

In addition, the 3D VR models improve the surgeon’s ability to provide first-rate surgical care by addressing limitations in the current imaging and surgical planning standard of care. Finally, patients may prevent undergoing damaging treatment for their prostate cancer, such as adjuvant or salvage radiation and androgen deprivation therapy.

“Further work may focus on the addition of other anatomical structures and use of the 3D models as a training tool,” the researchers said. “Additionally, intermediate- and long-term outcomes in these patients should be assessed to ensure the observed effects are durable.”