Comparative Analysis of Robot-Assisted and Open Approach for PSMA-Radioguided Surgery in Recurrent Prostate Cancer - Beyond the Abstract

The use of positron emission tomography (PET) targeting prostate-specific membrane antigen (PSMA) has improved the detection of prostate cancer (PCa) metastases and has led to a shift from systemic therapy to metastasis-directed therapy (MDT) in selected cases.

In this context, PSMA-radio-guided surgery (PSMA-RGS) has emerged as a surgical strategy to improve the intraoperative detection of PCa lesions. Traditionally, open surgical procedures have been the standard in PSMA-RGS as fibrotic changes after previous surgery and/or radiation therapy or atypical located lesions might impede minimal-invasive surgery. Furthermore, only rigid gamma probes for laparoscopy were available until in recent years novel DROP-IN gamma probes could be introduced into the clinic routine. Thus, the role of minimally invasive techniques remains poorly understood.

We performed a retrospective comparative analysis of oncologic and surgical outcomes in 85 patients with recurrent PCa who underwent either open (n=61) or robotic (n=24) salvage PSMA-RGS within 2021-2022 at Martini-Klinik, a tertiary care center solely dedicated to prostate cancer treatment.

In our analysis, we found that both surgical approaches resulted in comparable oncologic outcomes, with similar rates of complete biochemical response and biochemical recurrence-free survival.

Although the robot-assisted approach increased operative time (median 152 min vs. 110 min), no Clavien-Dindo III -V complications were reported in this group. This highlights the safety of the robot-assisted approach and suggests it may enhance the quality of life for patients.

However, it is worth noting that robot-assisted surgery was recommended only in selected cases. Specifically, ideal candidates were patients with unilateral positive pelvic lesions or retrovesical lesions with a low disease burden. Especially in patients with retrovesical lesions, the robotic approach seems to be of value as it is easy to reach those lesions via a robotic approach. Patients with higher disease burden or suspected more challenging cases/locations such as presacral or pararectal lymph node involvement underwent open surgery. In addition, the prior surgical approach to RP was considered when counseling patients with patients who underwent open radical prostatectomy being more likely to also receive an open PSMA-radio-guided salvage lymph node dissection.

The advantages of robot-assisted PSMA-RGS with the novel DROP-IN gamma probe technology include better visualization and maneuverability within the pelvis, which might allow the surgeon to target lesions more effectively than with conventional laparoscopic gamma probes while minimizing the surgical trauma compared to an open procedure.

Despite the inevitable limitations, which include limited sample size and retrospective design, our study contributes valuable insights that warrant further investigation and represent a promising step toward optimizing patient care for PCa recurrence.

Link to video: https://app.frame.io/presentations/4dda7452-e104-4080-9f7b-7788afa70e7b

Written by: Francesca Ambrosini, MD & Prof. Tobias Maurer, MD, FEBU; Martini-Klinik Prostate Cancer Center, University Hospital Hamburg-Eppendorf, Hamburg, Germany

Read the Abstract