Abstract:
Objective To investigate the effects of lymph node metastasis(LNM) and relevant factors on survival of the patients with EC from the high- and low-incidence areas,and to evaluate the new TNM staging. Methods The questionnaire, home interview and/or telephone were performed for survival followup on EC patients. The Chi-square test, Logistic regression, Kaplan-Meier survival analysis, Log rank test and multivariate Cox regression model were applied to assess the impacts of LNM on survival of patients. Results The survival time of LNM negative patients (n=7 945) was significantly longer than that of LNM positive patients (n=5 621) (P=1.9E-162). The survival time in N1, N2 and N3 patients with EC was gradually reduced (P=4.2E-20). The positive rate of LNM in HIA patients was signifi cantly higher than that in LIA patients (P=1.4E-5),however the survival time in HIA patients was signifi cantly longer than that in LIA patients (P=1.7E-39).The positive rate of LNM in younger patients (≤50 years) was slightly higher than that in elderly patients (>50 years) (P=0.003), while the survival time in younger patients (≤50 years) was signifi cantly longer than that in elderly patients (>50 years) (P=2.3E-31); the positive rate of LNM in lower segment EC patients was signifi cantly higher than that in the middle and upper segments EC patients (P=8.6E-24),while the survival time of LNM in lower segment EC patients was signifi cantly longer than that in the middle and upper segments EC patients (P=0.03). Multivariate regression analysis showed that HIA and LIA, gender, age at diagnosis, tumor location, differentiation, and invasion were independent factors for LNM and survival of patients with EC. The risk of poor prognosis was successively increased in N1, N2 and N3 patients with EC (HRN1=1.8, HRN2=2.5, HRN3=2.7). Conclusion The survival time of LNM positive patients was signifi cantly lower than that of LNM negative patients. With the number of LNM increased, survival time of patients was signifi cantly decreased. Patients in HIA, younger and lower segment had signifi cantly higher positive rates of LNM,but shorter overall survival than those in LIA, elderly, middle and upper segment EC patients.