Clinical Significance Of Lymph Nodes Micrometastases In Stage Ⅱ Rectal Cancer Patients

Objective: To explore the clinical significance of lymph node micrometastases in stage II rectal cancer patients.Methods: Forty-two patients with rectal cancer undergone total mesorectal excision between January 2000 and August 2001 were included, 484 lymph nodes were studied in paraffin blocks that had previously been considered free by conventional histopathological examination. These nodes were submitted to immunohistochemical analysis using CK20 monoclonal antibodies to identify micrometastases. Five-year follow-up information was obtained on these patients. Observed survival rates were assessed respectively in the patients with and without micrometastases.Results: Micrometastases were detected in 33 lymph nodes (6.82%, 33/484) of 15 cases (35.7%, 15/42). The five-year survival rate was 40.0% in the group with micrometastases, whereas in the patients without micrometastases, the survival rate was 92.6% (P=0.000, by the log-rank test). By multivariate Cox regression analysis, lymph node micrometastases was closely correlated with post-operative recurrence or metastatsis, the value of RR was 11.435.Conclusion: Detection of micrometastases is an important prognostic tool in stage II rectal cancer. In this study, lymph nodes micrometastases is an independent prognostic factor for overall survival .These patients may then benefit from adjuvant chemotherapy.