Laparoscopic Extraperitoneal Approach to Bilateral Pelvic Lymph Node Dissection in Low Rectal Cancer: Technique with Video and 3D Modeling.

BACKGROUND Lateral pelvic lymph node dissection for rectal cancer is a difficult technique due to the complex pelvic anatomy. Recent series have underlined the importance of lateral lymphadenectomy in selective patients to prevent local recurrence of rectal cancer. METHODS A 65-year-old woman was diagnosed with locally advanced rectal adenocarcinoma of the low rectum with right and left lateral pelvic lymph nodes of respectively 9 and 13 mm. After chemotherapy followed by radiotherapy, the size of the right internal iliac lymph nodes remained enlarged to 5 mm. A laparoscopic extraperitoneal approach was used for total mesorectal excision, complete mesocolic excision, and bilateral lateral lymph node dissection. The extraperitoneal space was divided into the subperitoneal space dissected by a transanal approach and the retroperitoneal space dissected by a transabdominal approach. RESULTS The operating time was 303 min, and the estimated blood loss was 270 ml. No intraoperative adverse events occurred. Bilateral lymph node dissection was performed with obturator nerve and neurovascular bundle sparing. A postoperative complication classified as Clavien 3a arose with a pelvic infection but no anastomotic leakage. Final pathology disclosed T3N1M0 adenocarcinoma with free surgical margins. The patient never had urinary dysfunction. CONCLUSIONS The laparoscopic extraperitoneal approach to lateral pelvic lymph node dissection is feasible. For lateral lymph node dissection, the transanal approach may have some advantages over the standard transabdominal approach, with better visibility of and access to the distal internal iliac area. This video may help oncological surgeons to perform this new and complex procedure.