Colorectal Cancer
Copyright ©2005 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jan 21, 2005; 11(3): 319-322
Published online Jan 21, 2005. doi: 10.3748/wjg.v11.i3.319
Pathological study of distal mesorectal cancer spread to determine a proper distal resection margin
Gao-Ping Zhao, Zong-Guang Zhou, Wen-Zhang Lei, Yong-Yang Yu, Cun Wang, Zhao Wang, Xue-Lian Zheng, Rong Wang
Gao-Ping Zhao, Zong-Guang Zhou, Wen-Zhang Lei, Yong-Yang Yu, Cun Wang, Zhao Wang, Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
Xue-Lian Zheng, Rong Wang, Division of Digestive Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
Author contributions: All authors contributed equally to the work.
Supported by the Key Project of National Outstanding Youth Foundation of China, No. 39925032
Correspondence to: Dr. Zong-Guang Zhou, Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China. zhou767@21cn.com
Telephone: +86-28-85422484 Fax: +86-28-85422484
Received: March 3, 2004
Revised: March 8, 2004
Accepted: April 5, 2004
Published online: January 21, 2005
Abstract

AIM: Local recurrence after curative surgical resection for rectal cancer remains a major problem. Several studies have shown that incomplete removal of cancer deposits in the distal mesorectum contributes a great share to this dismal result. Clinicopathologic examination of distal mesorectum in lower rectal cancer was performed in the present study to assess the incidence and extent of distal mesorectal spread and to determine an optimal distal resection margin in sphincter-saving procedure.

METHODS: We prospectively examined specimens from 45 patients with lower rectal cancer who underwent curative surgery. Large-mount sections were performed to microscopically observe the distal mesorectal spread and to measure the extent of distal spread. Tissue shrinkage ratio was also considered. Patients with involvement in the distal mesorectum were compared with those without involvement with regard to clinicopathologic features.

RESULTS: Mesorectal cancer spread was observed in 21 patients (46.7%), 8 of them (17.8%) had distal mesorectal spread. Overall, distal intramural and/or mesorectal spreads were observed in 10 patients (22.2%) and the maximum extent of distal spread in situ was 12 mm and 36 mm respectively. Eight patients with distal mesorectal spread showed a significantly higher rate of lymph node metastasis compared with the other 37 patients without distal mesorectal spread (P = 0.043).

CONCLUSION: Distal mesorectal spread invariably occurs in advanced rectal cancer and has a significant relationship with lymph node metastasis. Distal resection margin of 1.5 cm for the rectal wall and 4 cm for the distal mesorectum is proper to those patients who are arranged to receive operation with a curative sphincter-saving procedure for lower rectal cancer.

Keywords: Lower rectal cancer; Mesorectal cancer spread; Sphincter-saving procedure; Lymph node metastasis