Standardized Robotic Lateral Pelvic Lymph Node Dissection for Advanced Rectal Cancer

Standardized robotic lateral pelvic lymph node dissection for advanced rectal cancer: a 3- zone, 2-space anatomical approach.

Introduction and objectives

Lateral pelvic lymph node dissection (LPLND) is essential in managing locally advanced rectal cancer with persistent lateral nodes after neoadjuvant chemoradiation. The procedure’s complexity arises from anatomical constraints and the need for nerve preservation. We aimed to describe a standardized robotic technique to improve safety, reproducibility, and oncological outcomes.

Methods

A 3-zone, 2-space approach was developed, focusing on anatomical dissection along fascial planes. Key anatomical boundaries included: cranial (1 cm proximal to the common iliac artery), posterior (presacral fascia), medial (internal iliac artery), lateral (iliopsoas and obturator internus muscles), and distal (Alcock’s canal). Zone 1 extended from ureter to obliterated umbilical artery; Zone 2 from obliterated umbilical artery to external iliac vessels; Zone 3 from external iliac vessels to genitofemoral nerve. A 56-year-old male with ycT3N2M0 rectal adenocarcinoma and a 9 mm persistent left lateral pelvic node underwent robotic abdominoperineal resection with LPLND.

Results

The robotic approach enabled safe identification and preservation of vital structures. Complete clearance of fibrofatty and lymphatic tissue in all three zones was achieved without intraoperative complications. Histopathology confirmed 10 of 18 lymph nodes positive with tumor regression grade 2 and clear resection margins. The patient recovered uneventfully.

Conclusions

This standardized robotic LPLND provides a reproducible method ensuring optimal anatomical dissection and adequate oncological clearance in advanced rectal cancer, supporting improved surgical safety and outcomes.