Brief Article
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World J Gastroenterol. Nov 14, 2010; 16(42): 5375-5379
Published online Nov 14, 2010. doi: 10.3748/wjg.v16.i42.5375
Patterns of lymph node metastasis are different in colon and rectal carcinomas
Hao Wang, Xian-Zhao Wei, Chuan-Gang Fu, Rong-Hua Zhao, Fu-Ao Cao
Hao Wang, Xian-Zhao Wei, Fu-Ao Cao, Chuan-Gang FU, Department of Colorectal Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
Rong-Hua Zhao, Department of Surgery, College of Medicine University of Saskatchewan, Saskatoon, SK S7N0W8, Canada
Author contributions: Wang H and Wei XZ contributed equally to this work; Wang H, Wei XZ, Fu CG, Zhao RH and Cao FA designed the research; Wang H, Wei XZ, Fu CG and Cao FA performed the research; Wang H, Wei XZ, Fu CG and Zhao RH analyzed the data; Wang H, Wei XZ, Fu CG, Zhao RH and Cao FA prepared the manuscript.
Supported by The Science and Technology Commission of Shanghai Municipality, No. 07DZ1950 and 09ZR1400400
Correspondence to: Chuan-Gang Fu, MD, Chief, Department of Colorectal Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China. fugang416@126.com
Telephone: +86-21-81873343 Fax: +86-21-81873343
Received: May 28, 2010
Revised: August 14, 2010
Accepted: August 21, 2010
Published online: November 14, 2010
Abstract

AIM: To describe patterns of lymph node metastasis in invasive colon and rectal carcinomas.

METHODS: Clinical data of 2340 patients with colorectal carcinoma (stage I to III) who received radical resection, was retrospectively reviewed. Of the 2340 patients, 1314 patients suffered from rectal carcinoma and 1026 from colon carcinoma. Patients with rectal cancer who received neoadjuvant chemoradiation therapy were excluded. Statistical analysis was performed using Mann-Whitney, χ2 and Cochran’s and Mantel-Haenszel tests (SPSS 15.0). A two-tailed P < 0.05 was considered statistically significant.

RESULTS: Lymph node retrieval in the rectal carcinoma group was significantly lower than that in the colon carcinoma group (P < 0.001), while positive lymph node retrieval in the rectal carcinoma group was significantly higher than that in the colon carcinoma group (P < 0.001). The proportion of lymph node positive (N+) cases was higher (patients with one or more positive lymph nodes) in the rectal carcinoma group (P = 0.004). The number of N+ cases was compared at different T stages (T1-T4) to eliminate background bias and the results were confirmed (P < 0.001). In addition, the lymph node ratio (the ratio of number of positive lymph nodes over the number of lymph nodes examined) of stage III cases in the rectal carcinoma group was significantly higher than that in the colon carcinoma group (P < 0.001).

CONCLUSION: Rectal carcinomas seem more prone to metastasize to the lymph nodes than colon carcinomas, which may be of potential clinical significance.

Keywords: Lymph node; Metastasis; Colon; Rectum; Neoplasms