Does lateral lymph node dissection for low rectal cancer improve overall survival? Protocol for a systematic review and meta-analysis

INTRODUCTION: The best therapeutic strategy for treating lateral lymph nodes in patients with advanced mid to low rectal cancer remains unknown. Our objective is to determine which therapeutic strategy – lateral lymph node dissection versus radiochemotherapy – offers the best overall and recurrence-free survivals for these patients. METHODS AND ANALYSIS: We will perform a systematic review and meta-analysis aiming at determining the overall and recurrence-free survivals of patients with total mesorectum excision with and without lateral lymph node dissection, in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. MEDLINE, Embase, Cochrane and Web of Science will be searched from inception to the 16th of January 2019 for original studies written in English or in French including patients who benefited from lateral lymph node dissection for low rectal cancer and reporting overall survival for patients with and without lateral lymph node dissection. Hazard ratios of overall and recurrence-free survivals extracted from included studies will be combined and compared between patients with and without lateral lymph node dissection. Risk of bias will be assessed by using the Newcastle-Ottawa scale. The systematic review and meta-analysis protocol is registered in the International Prospective Register of Ongoing Systematic Reviews (PROSPERO) with number CRD42019123181. ETHICS AND DISSEMINATION: No ethical clearance is required for this study. This review will be published in a peer- reviewed journal and will be presented at various national and international conferences.