Reappraisal of the lateral mesorectum and its clinical importance

Abstract

The mesentery has been defined as a double fold of the peritoneum connecting some regions of the intestine to the posterior abdominal wall. It emerges from the superior mesenteric root region and fans out to span the intestine from the duodenum to the rectum. The mesorectal is a continuation of the intraperitoneal mesentery in the pelvic cavity. The lateral structure of the rectum is complex and the traditional view calls it the lateral ligament of the rectal. However, this structure could be called the lateral mesorectum from the perspective of embryonic development and membrane anatomy. The lateral mesorectum is the bridge of the vessels, lymphatic, and nerves between the rectum and the pelvic wall. It anchors the rectum to the lateral pelvic wall and is the anatomical basis of lateral lymph node metastasis in low rectal cancer. Meanwhile, it is important to identify the lateral mesorectum and its surrounding structure to radically resect the tumor and protect the pelvic autonomic nerve during the total mesorectal excision procedure.