Does perifascial rectal excision (i.e. TME) when combined with the autonomic nerve-sparing technique interfere with...

OBJECTIVE: The lymphatic drainage from the rectum was studied to evaluate if the autonomic nerve sparing dissection may interfere with the operative radicality and might result in metastatic lymph nodes being overlooked and left in situ. PATIENTS AND METHODS: 50 consecutive patients had an extended extrafascial rectal excision resection for cancer. In 19 of the 50 patients activated carbon particles (CH40) were injected preoperatively into the rectum. The autonomic nerves with surrounding connective tissue were serially dissected from the resected specimen, carefully sliced at 5-mm intervals and collected for histological study. Lymph nodes along the axial and lateral drainage routes were examined, and the inclusion of CH40 in the nodes was microscopically studied according to the site of CH40 injection. RESULTS: Lymph nodes within the connective tissue along the dissected autonomic nerves were demonstrated in 47 of the 50 cases. Two of 50 cases had positive nodes along preaortic plexus or pelvic plexus, and a case with nodal involvement along the pelvic plexus had poor prognosis in spite of nerve excision. CH40 when injected into the rectum above the peritoneal reflection was demonstrated in the vast majority of the axial nodes, while in only one lymph node along the preaortic plexus when injected in the rectum above the peritoneal reflection. On the other hand when injected in the rectum below the peritoneal reflection, CH40 was demonstrated both in axial and lateral nodes as well as in lymph nodes along bilateral pelvic plexuses, right hypogastric nerve, superior hypogastric plexus, preaortic plexus and mesenteric plexus as well. CONCLUSIONS: When located above the peritoneal reflection a rectal carcinoma will spread preferentially along the upper axial route, while a carcinoma located below the peritoneal reflection will also spread laterally and along the autonomic nerves. It was inferred that lymphatic flow along the autonomic nerves came up from the rectum below the peritoneal reflection mainly through a so-called lateral ligament but its clinical significance was negligible. Therefore doing TME with autonomic nerve preservation does not imply a less radical surgery from the point of lymphatic spread.