The efficacy and safety of lateral lymph node dissection for patients with rectal cancer: A systematic review and meta-analysis

Lateral lymph node metastasis in rectal cancer was first reported in the 1950s, since then, there has been an on-going debate about the value of lateral lymph node dissection (LLND) in the management of rectal cancer. We carried out a systematic review and meta-analysis to evaluate the value of LLND for the patients with rectal cancer. To collect clinical studies for the comparison of LLND and non-LLND in patients with rectal cancer, PubMed, Embase, Cochrane Library, Web of Science, and Google Scholar databases were searched from inception to 2019.A total of 26 studies, including 6865 patients were enrolled. Data processing and statistical analyses were performed using Stata V.15.0 software and Review Manager 5.3 software. Outcome measures included the 5-year survival rate, recurrence rate, perioperative outcomes, urinary function, and male sexual function. Regarding efficacy, our meta-analysis results showed no difference in 5-year disease-free survival rate and local recurrences between the two groups, the Hazard Ratio (HR) and 95% confidence interval (CI) was1.07 and 0.89 to 1.28 (P = 0.496),and the Odds Ratio(OR) and 95% CI were 0.90 and 0.76 to 1.06 (P = 0.208), respectively. Concerning safety, the incidence of urinary dysfunction and male sexual dysfunction was significantly increased in the LLND group (OR = 2.14, 95%CI = 1.21–3.79, P = 0.009), and (OR = 4.19, 95%CI = 1.55–11.33, P = 0.005), respectively. In conclusion, LLND did not improve the long-term prognosis of patients with rectal cancer, and was associated with increased urinary dysfunction and male sexual dysfunction.