Objective: To investigate the association between the number of retrieved lymph nodes and the prognosis of stage II colorectal cancer.
Methods: 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.
Results: 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).
Conclusions: 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.