Introduction/Background Grade 1 (G1) endometrial cancer (EC) are well differentiated cells which at diagnosis, most are confined to the uterine corpus and ovary (stage 1), hence mainly treated with surgery alone and often in benign gynaecology service.

The aim of this study is to evaluate the independent risk factors for recurrence and mortality and to describe the recurrence patterns of G1 endometrial carcinoma.

Methodology Data from 238 cases of G1 endometrial cancer who were operated at Oxford University Hospitals between 2009 – 2019, were analysed by IBM©SPSS Statistics 22.0.

We used independent samples t-test to compare continuous variables and Pearson chi-square or Fisher’s extract test for categorical variables. Survival rates were calculated from Kaplan-Meier curves and compared using log-rank tests. Univariate and multivariate Cox proportional hazards analysis was conducted to assess the potential risk factors for relapse and mortality.

Results 14/238 cases had recurrence (5.88%) with Cancer specific death rate of 2/238 = 0,84%.

Mean time interval from surgery until relapse was 30 months and half the patients were asymptomatic and diagnosed during their follow up visits, with relapse occurring mainly in the vaginal vault.

Multivariable Cox proportional hazards analysis for the risk of recurrence demonstrated that only depth of myometrial invasion >50% and serosal breach were the only independent risk factors of recurrence in our study.

Conclusion The recurrent rate found in our study is still low compared to higher grade endometrial cancers, however some features of higher grade ECs are seen in this group as well, making them high risk to benefit from regular post operative surveillance.

Disclosures All authors declare that they have no conflicts of interest.