Background According to the data of the role of adjuvant radiation therapy (RT) in EC stage I, EC IaG3 can be separated as a high intermediate subgroup. We evaluated long-term results of treatment of intermediate and high risk of EC.

Methods In a retrospective study included 1143 patients. 918 women - intermediate risk and 225 patients with high-risk of EC who received treatment N.N. Alexandrov National Cancer Center of Belarus. We use data from the Belarusian Cancer Registry.

Result Overall (OS), cancer-specific (CSS) and disease-free (DFS) 5-year survival rate in the EC IB G1-2 stage was 83.7 ±1.6%, 91.2±1.2%,88.4±1.4%, in EC of stage IA G3 stage ¬ 76.2±2.2%, 82.4±2.0%, 79.3±2.2%, in EC IB G3 stage ¬ 70,8±3.8%, 81.1±3.3%, 81.1±3.3%, non-endometrioid EC stage I ¬ 58.6±5.7%, 69.3±5.6%, 68.2±5,6%. We’ve got statistic significant differences between the subgroups of intermediate risk IB G1-2 and IaG3 stage of EC (pos=0.022, pcss=0.00009, pdfs=0.0002) and statistic significant differences in OS rate between IaG3 stage of EC and high-risk stage I of EC (pos= 0.039) which may support for highlight EC stage IaG3 for separate subgroup. However, we’ve not gotten any significant differences between EC stage IaG3 and EC stage IbG3 (pos=0.212, pcss=0.439, pdfs=0.899).

Conclusion EC stage IaG3 can be highlighted as an individual high intermediate subgroup on the grounds of study of the long-term results of treatment. However, the treatment of intermediate and high intermediate risk of EC isn’t different, but the high-risk of EC has a difference because of using adjuvant chemotherapy in the treatment scheme.