Nodal metastasis in the distal mesorectum: need for total mesorectal excision of rectal cancer

Locoregional failure of rectal cancer is a troublesome problem and a major cause of morbidity and mortality following curative surgery. The mesorectum has been regarded as an important site in local failure after surgery of rectal cancer. Total mesorectal excision (TME) has been raised by some colorectal surgeons to prevent early local recurrence. This study was performed to ascertain the incidence of metastatic lymph nodes in the distal mesorectum (DMR) of the colorectal cancer patient. We also examined the clinicopathologic risk factors of distal mesorectal metastasis. Eight of 53 patients had positive metastatic lymph nodes in DMR. Twenty-seven patients were Dukes B and 26 patients were Dukes C stage. Out of 26 Dukes C patients, 8 patients (30.8%) had metastatic lymph nodes in the DMR. However, there was no significant difference in risk factors between DMR positive and DMR negative patients with Dukes C stage. In conclusion, the incidence of metastatic lymph nodes in DMR was about 30.8%, therefore the mesorectum especially the DMR should be removed completely by total mesorectal excision to eradicate the metastatic lymph nodes which may cause local recurrence.