Feasibility of Image-guided Navigation with Electromagnetic Tracking During Robot-assisted Sentinel Node Biopsy:A Prospective Study

Background and objective: Image-guided surgical navigation (IGSN) can enhance surgical precision and safety. The expansion of minimally invasive surgery has increased the demand for integration of these navigation systems into robot-assisted surgery. Our objective was to evaluate the integration of electromagnetic tracking with IGSN in robot-assisted sentinel lymph node biopsy (SLNB). Methods: We conducted a prospective feasibility study to test the use of IGSN in SLNB. In total, 25 patients scheduled for SLNB at The Netherlands Cancer Institute were included (March 2022 to March 2023). SLNB using IGSN was performed using a standardised technique with a da Vinci robot (Intuitive Surgical, Sunnyvale, CA, USA) in four-arm configuration. Feasibility was determined as the percentage of sentinel nodes (SNs) successfully identified via IGSN. Successful SN resection was defined as SNs correctly localised via navigation and validated ex vivo with a gamma probe. Surgeon feedback on the robot-assisted IGSN workflow was evaluated using the System Usability Scale (SUS). Key findings and limitations: In accordance with the protocol, the first five patients were used for workflow optimisation, and the subsequent 20 patients were included in the analysis. IGSN led to successful identification of 91% (50/55) of the SNs. There were no complications associated with navigation. The surgeon feedback (SUS) was 60.9, with lowest scores reported for the user interface and workflow integration. Conclusions: IGSN during robot-assisted surgery was feasible and safe. The technique allowed identification and removal of predefined small pelvic lymph nodes. Patient summary: We carried out a study on the feasibility of imaging-guided navigation in robot-assisted prostate surgery. Our results show that this technique is feasible, safe, and effective.</p

Surgical navigation for targeted retroperitoneal lymph-node removal: a randomised, controlled, phase 3 trialResearch in context

Summary: Background: Metastatic retroperitoneal lymph node dissection (LND) for nodal recurrence is applied for a variety of cancers, such as urological, gynaecological and rectal cancer. Precise localisation and resection of these lymph nodes (LNs) during surgery can be challenging, especially after previous radiotherapy or surgery. The objective of this study was to assess the added value of surgical navigation for targeted LND in the retroperitoneum. Methods: We performed an open-label randomised, controlled, phase 3 trial at the Netherlands Cancer Institute, Amsterdam. Eligible participants were over 18 years of age, scheduled for targeted retroperitoneal LND by laparotomy, with removal of one or more suspected (targeted) LN(s) as assessed by diagnostic imaging. Patients were randomised (1:1) between conventional LND and LND using surgical navigation, by means of a minimisation method stratified for tumour origin (urological, colorectal and other). For the surgical navigation, a digital 3D model of the patients' anatomy was created from diagnostic CT scans, including delineation of the targeted LN(s). The 3D model was linked to the patients’ position in the operation room. Using an electromagnetic tracking system, with a sterile tracked pointer, the actual position of the pointer was shown in the 3D model, enabling the surgeon to localize the targeted LN(s). The primary outcome of the study was the percentage of successful procedures. Success was defined as no residual target LN(s) visible on postoperative CT imaging. This study was registered with ClinicalTrials.gov, NCT05867095. Findings: From January 2017 to December 2020, 69 participants were included in the study, 35 (51%) in the conventional arm and 34 (49%) in the navigation arm. Four patients were not evaluable and excluded from further analysis; three in the conventional arm (patients withdraw from study participation), one in the navigation arm (discontinued surgery, misclassified diagnosis). According to intention-to-treat analysis, 50% (16/32) of the surgical procedures was successful in the conventional arm, versus 85% (28/33) in the surgical navigation arm (one-tailed p = 0.0028, 90% CI: 14%–56%). Using the Clavien-Dindo classification, the overall complication rate was comparable between the conventional arm and the navigation arm. Surgeons judged the surgical navigation setup as valuable, the median preference score to use surgical navigation was 3.7 (3.3–4.0) (scale 1–5), and the median system usability score was 75 (70–85) (scale 0–100). Interpretation: Surgical navigation allows for significantly better localisation and removal of target LN(s) in the retroperitoneum. Funding: This research was supported by the KWF-Alpe d'HuZes (NKI 2014-6596) and by an institutional grant of The Dutch Cancer Society and of the Dutch Ministry of Health, Welfare and Sport