Clinicopathological study on lymph node metastases in the mesorectum of rectal cancer / 中国普通外科杂志

ABSTRACT

Objective To investigate the patterns of mesorectum lymph node (LN) metastases of rectal cancer. Methods Rectal cancer specimens obtained by total mesorectum excision were treated with lymph node revealing solution to retrieve all the nodes, and examined by routine pathology and immunohistochemical staining. Results A total of 443 LN in 26 specimens were harvested, with 128 nodes(28 9%)in 23 cases (88 5%) found positive. Positive nodes with the size less than 5 mm accounted for 59%. Among the 23 metastatic cases, there were 14 cases with tumors locating in the posterior wall, 69 out of 71 positive nodes were found along the superior rectal artery. In the other 9 cases, tumors were found in the lateral wall, 29 out of 57 positive nodes were found around ipsilateral branches of superior rectal artery,7 were around the contralateral branches, 4 were around the ipsilateral branches of middle rectal artery. Conclusions Most positive LN were less than 0 5 cm in diameter. LN metastasis of rectal cancer have close relationship with tumor location. Tumors in the posterior wall tend to spread upward along the superior rectal artery, while tumors in the lateral wall may have upward and lateral LN metastases simultaneously, with most metastatic LN found ipsilaterally.