[Laparoscopic surgery of total mesorectal excision based on pelvic membrane anatomy]

Total mesorectal excision (TME) is the basic principle of surgery in rectal cancer which requires en bloc removal of the tumor and its regional lymph nodes. This conincides with the theory of membrane anatomy that emphasizes en bloc resection and avoids cancer leakage. The basis of membrane anatomy is the fusion of peritoneum and three key pointsare needed to understand the fusion and fusion fascia:(1) the fusion only occursin peritoneum; (2) the inside of fusion fascia cannot be separated; (3) the fusion can be diversiform. Only mastering these key points can we comprehend and apply this theory dialectically. The membrane anatomy in rectum is different from stomach or colon because of its specific location. The posterior space of rectum is filled with the loose connective tissue which is the degeneration of peritoneum fusion. In this space, the anterior lay of presacral fascia fuses with the proper fascia of rectum at the S4 level and separates the space into the retrorectal space and the supralevator space. Denonvilliers fascia is the fusion fascia in front of rectum, which forms the prerectal space and retroprostatic space, and extends to lateral pelvic wall with fusion of the parietal fascia of pelvis, covering the neurovascular bundle (NVB) together. The proper fascia of rectum surrounds the middle rectal artery, the pelvic plexus rectal branch and the adipose tissue to form the lateral rectal pedicle at 10 o'clock and 2 o'clock near the pelvic floor. At the level of levator ani hiatus, the fusion of levator ani muscle fascia and the proper fascia of rectum forms the Hiatal ligament, which fixs the anal canal and closes the levator ani hiatus.This article intends to discuss the above points from the perspective of membrane anatomy, in order to better guide surgeons to complete laparoscopic total mesorectal excision for rectal cancer.