The effect of lateral lymph node dissection on the treatment of stageⅡ/Ⅲlow rectal cancer with mesorectal excision / 中国医师进修杂志

ABSTRACT

Objective To confirm the noninferiority of mesorectal excision (ME) alone to ME combined with lateral lymph node dissection (LLND) in terms of efficacy. Methods Eligibility criteria included histologically proven rectal cancer at clinical stageⅡ/Ⅲ; main lesion located in the rectum. Patients were intra-operatively allocated to undergo ME combined with LLND or ME alone in a randomized manner. The primary endpoint was relapse-free survival, with a noninferiority margin for the hazard ratio of 1.34. Secondary end points included overall survival and local-recurrence-free survival. Results In total, 502 patients from November 11, 2010 to October 1, 2017 were randomized to the ME combined with LLND (252 patients) and ME alone (250 patients) groups. The 5-year relapse-free survival in the ME combined with LLND and ME alone groups were 73.4% and 73.3%, respectively (hazard ratio1.07, 90.9% CI 0.84— 1.36), with one sided P value for noninferiority of 0.0547. The 5-year overall survival, and 5-year local-recurrence-free survival in the ME combined with LLND and ME alone groups were 92.6% and 90.2% , and 87.7% and 82.4% , respectively. The numbers of patients with local recurrence were 21 cases (8.3%) and 43 cases (17.2%) in the ME combined with LLND group and ME alone group (P=0.024). Conclusions The noninferiority of ME alone to ME combined with LLND is not confirmed in the intent-to-treat analysis. ME combined with LLND has a lower local recurrence, especially in the lateral pelvis, compared to ME alone.