A Feasible and Time-efficient Adaptation of NeuroSAFE for da Vinci Robot-assisted Radical Prostatectomy

BACKGROUND: The benefit of intraoperative neurovascular structure-adjacent frozen section examination (NeuroSAFE) of the prostate was demonstrated in open radical prostatectomy. In da Vinci robot-assisted prostatectomy (DVP), this approach is often avoided due to suspected difficulties in harvesting the prostate, loss in pneumoperitoneum, increased blood loss, and prolonged operating room (OR) time.

OBJECTIVE: To provide a detailed description of the technique, feasibility, and impact of the NeuroSAFE technique on OR time, blood loss, frequency of nerve sparing (NS), and positive surgical margins (PSMs) in DVP.

DESIGN, SETTING, AND PARTICIPANTS: We analyzed 1570 consecutive patients undergoing DVP from 2004 to 2012. NeuroSAFE was performed in 1178 patients.

SURGICAL PROCEDURE: The prostate was intraoperatively harvested via an extension of the camera trocar incision without undocking the robotic arms. Blood spillage from the dorsal vein complex due to the loss of pneumoperitoneum was avoided by upward traction on the transurethral catheter. After prostate removal, pneumoperitoneum was reestablished by closing the extended incision with running sutures and repositioning the optical trocar. The NeuroSAFE procedure consisted of intraoperative bilateral frozen sections covering the entire neurovascular bundles adjacent prostate surface.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We compared OR time, blood loss, NS frequency, and PSMs in non-NeuroSAFE versus NeuroSAFE DVP.

RESULTS AND LIMITATIONS: There was no significant difference in blood loss (253.5±204.4ml vs 265.8±246.7ml; p=0.49) and OR time (220min ± 51 vs 224min ± 64; p=0.22). No complications associated with specimen harvesting occurred. NS rate increased significantly with versus without NeuroSAFE (overall 97% vs 81%; pT2 99% vs 90%, pT3a 94% vs 74%, pT3b 91% vs 30). PSM rate dropped significantly with NeuroSAFE (overall 16% vs 24%; pT2 8% vs 15%, pT3a 22% vs 39%, pT3b 49% vs 67%; all p<0.05).

CONCLUSIONS: We demonstrate a time-efficient and safe adaption of the NeuroSAFE technique to DVP.

PATIENT SUMMARY: We describe a feasible and secure adaption of the neurovascular structure-adjacent frozen section examination (NeuroSAFE) procedure for da Vinci robot-assisted prostatectomy. We showed that there was no increased blood loss and operating room time. We maximized the nerve-sparing frequency and could reduce positive surgical margins even in non-organ-confined tumors.