Lateral lymph node dissection for mid-to-low rectal cancer: is it safe and effective in a practice-based cohort?

Most evidence regarding lateral lymph node dissection for rectal cancer is from expert settings. This study aimed to evaluate the safety and efficacy of this procedure in a practice-based cohort.

A total of 383 patients who were diagnosed with stage II-III mid-to-low rectal cancer between 2010 and 2019 and underwent primary resection with curative intent at a general surgery unit were retrospectively reviewed. After propensity matching, 144 patients were divided into the following groups for short- and long-term outcome evaluation: mesorectal excision with lateral lymph node dissection (n = 72) and mesorectal excision (n = 72).

This practice-based cohort was characterized by a high pT4 (41.6%) and R1 resection (10.4%) rate. Although the operative time was longer in the lateral dissection group (349 min vs. 237 min, p < 0.001), postoperative complications (19.4% vs. 16.7%, p = 0.829), and hospital stay (18 days vs. 22 days, p = 0.059) did not significantly differ; 5-year relapse-free survival (62.5% vs. 66.4%, p = 0.378), and cumulative local recurrence (9.7% vs. 15.3%, p = 0.451) were also in the same range in both groups. In the seven locally recurrent cases in the lateral dissection group, four had undergone R1 resection.

Lateral lymph node dissection was found to be safe in this practice-based cohort; however, the local control effect was not obvious. To maximize the potential merits of lateral lymph node dissection, strategies need to be urgently established to avoid R1 resection in clinical practice.