Association between the number of retrieved lymph nodes in stage II( colorectal cancer radical resection and its prognosis

Abstract

To investigate the association between the number of retrieved lymph nodes and the prognosis of stage II colorectal cancer. Clinical data of 380 patients with stage II colorectal cancer were analyzed retrospectively. SPSS 13.0 was used for data processing. Survival rate was calculated by Kaplan-Meier method, and risk factors related to prognosis of stage II colorectal cancer were analyzed by Logistic regression analysis. Recurrence rate and survival rate were assessed with Chi-squared test. The average number of lymph nodes retrieved from 56 patients who developed recurrence or metastasis in 5 year after surgery was 9.5, and 16.3 from patients who had no recurrence or no metastasis(P<0.01). The number retrieved from 97 patients who died in 5 years after surgery was 11.1, and 16.7 from survivors. Patients were divided into 2 groups:>or=12 group and <12 group. The 5-year survival rate was 83.9% in >or= 12 group and 62.0% in < 12 group, respectively(P<0.01), the recurrence rate was 6.4% in >or=12 group and 25.7% in < 12 group (P<0.01). The univariable analysis showed that the number of retrieved lymph nodes was significantly associated with the survival and recurrence in patients with stage II colorectal cancer (P<0.05). The number of retrieved lymph nodes is associated with the prognosis of stage II colorectal cancer. Patients with more retrieved lymph nodes have a higher survival rate.