Abstract:Objective:To study the relationship of the site of original tumor and the local infiltraton of colon carcinoma with lymph node metastasis, in order to provide a basis for better surgical therapy for patients with colon cancer.
Methods :The pathological and clinical data of 118 cases of the colon carcinoma were recorded and analyzed. The invasive depth of tumor was divided into T1, T2, T3, and T4 stage according to AJCC standard. The lymph node stage was determind according to our country′s and Japanese′s standard.
Results:Of 118 cases, 49 cases (41.5%) showed LN metastasis. In a total retrieved and examined 1824 LNS (average of 15.29 lymph nodes per case), 277 lymph nodes (15.2%) showed metastasis. In three groups of the pericolon lymph nodes (Group 0~5 cm, Group 5~10 cm, and Group >10 cm respectively from the tumor), the metastatic rate of lymph nodes was 34.7%, 2.5% and 1.7%, respectively. The metastatic rate of LN in right colon was significantly higher than that in left colon (52.0% vs 33.8%, P<0.05). All cases were divided into four groups (T1, T2, T3, and T4), based on the depth of tumor invasion. The metastatic rate of N1，N2, N3 and N4 was 18.2％, 9.1%, 4.5% and 0.0% in Group T2; 40.8%,18.4%, 8.2% and 2.0% in Group T3;The LN metastasis of
and 53.8%, 28.2%, 12.8% and 5.1% in Group T4, respectively. There was significant difference among the group T2, T3, and T4 (P<0.01).
Conclusions:As the depth of tumor invasion is increased, the metastatic rate of lymph nodes is markedly increased. The metastasis of pericolon lymph nodes is mainly in those nodes located within 0~5 cm of the tumor, but rarely in those nodes located more than 10 cm from the tumor. The metastatic rate of lymph node in right colon cancer is significantly higher than that in left colon cancer. D3 radical resection is necessary for colon carcinoma and dissection of the central lymph nodes should especially be carried out. The length of excised bowel should be 10 cm above and below the tumor.