Transanally assisted lateral pelvic lymph node dissection for rectal cancer

Although lateral pelvic lymph node dissection (LLND) might be an effective approach for patients with rectal cancer with lateral lymph node metastasis, it is technically challenging because of the anatomical complexity and location of the deep pelvis. An assistance by transanal approach might be useful for a successful LLND.

From September 2016 to May 2021, 39 patients with low rectal cancer underwent transanal total mesorectal excision with LLND. Among them, 18 patients underwent LLND using a conventional laparoscopic approach alone, while the remaining 21 underwent LLND using both conventional and transanal approaches. Their clinical outcomes were retrospectively compared.

The operation time for LLND on each side was significantly shorter in the transanal group (105 min vs. 54 min, P < 0.001). The intraoperative blood loss was also significantly less in the transanal group (40 g vs. 0 g, P = 0.031). The rate of overall postoperative complications ≥ grade II according to the Clavien-Dindo classification was significantly less in the transanal group (66.7% vs. 28.6%, odds ratio: 5.000, 95% confidence intervals: 1.313-19.047, P = 0.040). The number of harvested lateral lymph nodes in both groups was similar (8.5 vs. 8, P = 0.544).

The transanal approach for LLND reduced operative time, blood loss, and morbidity compared with the conventional approach alone in a cohort of patients with rectal cancer.