Laparoscopic Lateral Lymph Node Dissection Based on Membrane Anatomy for Lower Rectal Cancer: Surgical Technique and Short-Term Outcomes.

Abstract

Background: Lateral lymph node dissection (LLND) is an effective treatment for metastatic lateral lymph nodes (LLNs) in lower rectal cancer, but with high complication rates due to a complicated procedure. This study aimed to introduce a new technique for LLND based on membrane anatomy to simplify the procedure and report short-term outcomes. Methods: Twenty-three patients with clinical stage II-III lower rectal cancer underwent three-dimensional (3D) laparoscopic total mesorectal excision (TME) plus LLND between July 2018 and December 2020. Demographic data, perioperative variables, and oncologic outcomes were recorded and analyzed. Complications were graded using the Clavien-Dindo (CD) score. Results: Based on the theory of "four fasciae and three spaces," we proposed a fascia-to-space surgical approach to perform LLND. 3D laparoscopic TME plus LLND was performed successfully in all patients. The mean operating time was 172 minutes with a mean blood loss of 85 mL. Postoperative complications were present in 5 (17.4%) patients (CD I-II), including a case of urinary retention. The median number of harvested LLNs was 9, and positive LLNs were detected in 7 (30.4%) patients. After a median follow-up of 26.5 months, 2 (8.7%) patients developed liver metastases, but no local recurrence. Conclusions: Laparoscopic LLND based on membrane anatomy is a safe, feasible, and reproducible procedure and thus worthy of clinical promotion. Further studies with long-term follow-up in larger patient series are still required.