Background:Endometrial cancer (EC) has been one of the most general cancers with respect to gynecological malignancies; however, there are debates on clinical strategies concerning treatments especially for patients with grade 3 (G3) endometroid endometrial cancer (EEC). Present study aimed to evaluate the lymphatic metastasis (LM) related factors and figure out the necessity of lymphadenectomy for G3 EEC patients.Methods:From January 2009 to April 2019, 3751 EC patients were admitted to Obstetrics and Gynecology Hospital of Fudan University. Clinical characteristics include age, grade, stage, and clinical pathological features. A total of 1235 EEC patients were involved in the multivariable analysis. Three hundred and eighty-one patients were involved in the survival analysis and the data attributed to sufficient follow-up information. Kaplan-Meier curve and log-rank test were utilized to analyze the survival rate.Results:Among the 1235 EEC patients, 181 (14.7%) were categorized as G3 and 1054 (85.3%) were grade 1 to grade 2 (G1-2). Multivariate analysis demonstrated that lymphovascular space invasion, adnexal involvement, and cervical stroma involvement were independent risk factors of LM in G3 cohort with odds ratio 3.4, 5.8, and 8.9; 95% confidence interval 1.1-10.6, 1.5-22.4, and 2.8-28.0, respectively. LM rates increased from 3.3% (3/92) to 75% (9/12) for G3 EEC cohort as related factor numbers increased from one to three. There were no differences between G3 and G1-2 EEC in overall survival and progression free survival. Additionally, no survival advantage was observed for G3 EEC patients at early stage with different plans of adjuvant treatment.Conclusions:For G3 EEC patients without other pathological positive factor, the LM rate is lower than those with other pathological positive factor. Survival analysis showed no difference between G3 cohort and G1-2 cohort. Also, different adjuvant treatments had no impact on the overall survival for G3 EEC patients.“,”Background:Endometrial cancer (EC) has been one of the most general cancers with respect to gynecological malignancies; however, there are debates on clinical strategies concerning treatments especially for patients with grade 3 (G3) endometroid endometrial cancer (EEC). Present study aimed to evaluate the lymphatic metastasis (LM) related factors and figure out the necessity of lymphadenectomy for G3 EEC patients.Methods:From January 2009 to April 2019, 3751 EC patients were admitted to Obstetrics and Gynecology Hospital of Fudan University. Clinical characteristics include age, grade, stage, and clinical pathological features. A total of 1235 EEC patients were involved in the multivariable analysis. Three hundred and eighty-one patients were involved in the survival analysis and the data attributed to sufficient follow-up information. Kaplan-Meier curve and log-rank test were utilized to analyze the survival rate.Results:Among the 1235 EEC patients, 181 (14.7%) were categorized as G3 and 1054 (85.3%) were grade 1 to grade 2 (G1-2). Multivariate analysis demonstrated that lymphovascular space invasion, adnexal involvement, and cervical stroma involvement were independent risk factors of LM in G3 cohort with odds ratio 3.4, 5.8, and 8.9; 95% confidence interval 1.1-10.6, 1.5-22.4, and 2.8-28.0, respectively. LM rates increased from 3.3% (3/92) to 75% (9/12) for G3 EEC cohort as related factor numbers increased from one to three. There were no differences between G3 and G1-2 EEC in overall survival and progression free survival. Additionally, no survival advantage was observed for G3 EEC patients at early stage with different plans of adjuvant treatment.Conclusions:For G3 EEC patients without other pathological positive factor, the LM rate is lower than those with other pathological positive factor. Survival analysis showed no difference between G3 cohort and G1-2 cohort. Also, different adjuvant treatments had no impact on the overall survival for G3 EEC patients.