Objectives:To explore the prognostic relevance of the number and ratio of metastatic lymph nodes in resected Carcinoma of the ampulla of Vater(CAV).Methods:The clinical data of 155 patients who underwent pancreaticoduodenectomy(PD)for cancer of the ampulla of Vater between January 1990 and December 2010 were retrospectively analyzed.KaplanMeier method was used in survival analysis and Log rank method in comparison.Multivariate analysis was performed using Cox proportional hazards model.Results:Among these 155 patients,the in-hospital mortality rate was 4.5%,lymph node positive disease was21.3%,and the 5-year survival rate was 51.6%.Patients with a lymph node ratio(LNR)>20%were more likely to have tumor differentiation,depth of duodenal involvement,depth of pancreatic invasion,T-stage and TNM-Stage.The number of the metastatic lymph nodes is important prognostic factors of the CAV.Univariate analysis showed that the factors associated with the prognosis included tumor size(P=0.036),tumor differentiation(P=0.019),LNR(P=0.032),number of metastatic lymph nodes(P=0.024),lymph node metastasis(P=0.03),depth of pancreatic invasion(P=0.001),T-stage(P=0.002),TNM stage(P=0.001),elevated CA 19-9(P=0.000),and jaundice(P=0.021).Multivariate analysis showed that the factors associated with the prognosis were the number of metastatic lymph nodes(P=0.032;RR:1.283;95%CI:1.022-1.611),tumor size(P=0.043;RR:1.736;95%CI:1.017-2.963),and elevated CA 19-9(P=0.003;RR:3.247;95%CI:1.504-7.010).Conclusions:LNR is a useful factor for predicting the prognosis of the radical treatment for CAV,whereas the number of metastatic lymph nodes is the most important factor.Further research on the locations,number,and LNR will be clinically meaningful to improve survival in patients with CAV. Objectives: To explore the prognostic relevance of the number and ratio of metastatic lymph nodes in resected Carcinoma of the ampulla of Vater (CAV). Methods: The clinical data of 155 patients who underwent pancreaticoduodenectomy (PD) for cancer of the ampulla of Vater between Kaplan Meier method was used in survival analysis and Log rank method in comparison. Multivariate analysis was performed using Cox proportional hazards model. Results: Among these 155 patients, the in-hospital mortality rate was 4.5% lymph node positive disease was 21.3% and the 5-year survival rate was 51.6%. Patients with a lymph node ratio (LNR)> 20% were more likely to have tumor differentiation, depth of duodenal involvement, depth of pancreatic invasion, T-stage and TNM-Stage. The number of the metastatic lymph nodes is important prognostic factors of the CAV. Univariate analysis showed that the factors associated with the prognosis included tumor size (P = 0.036), tumo r differentiation (P = 0.019), LNR (P = 0.032), number of metastatic lymph nodes (P = 0.024), lymph node metastasis = 0.002), TNM stage (P = 0.001), elevated CA 19-9 (P = 0.000), and jaundice (P = 0.021) .Multivariate analysis showed that the factors associated with the prognosis were the number of metastatic lymph nodes (P = 0.032; RR: 1.283; 95% CI: 1.022-1.611), tumor size (P = 0.043; RR: 1.736; 95% CI: 1.017-2.963), and elevated CA 19-9 ; 95% CI: 1.504-7.010) .Conclusions: LNR is a useful factor for predicting the prognosis of the radical treatment for CAV, whereas the number of metastatic lymph nodes is the most important factor. Future research on the locations, number, and LNR will be clinically meaningful to improve survival in patients with CAV.