Therapy with a levonorgestrel-releasing intra-uterine system in atypical endometrial hyperplasia and low-grade endometrial cancer.

OBJECTIVE

Atypical endometrial hyperplasia and low-grade endometrial cancer are traditionally managed with hysterectomy. However, conservative treatment with a levonorgestrel-releasing intra-uterine system may be an alternative for selected patients. This study evaluated the efficacy of a levonorgestrel-releasing intra-uterine system in patients with atypical endometrial hyperplasia and low-grade endometrial cancer and identified factors associated with complete remission.

METHODS

This retrospective cohort study included patients treated between January 2013 and June 2025 for atypical endometrial hyperplasia or International Federation of Gynecology and Obstetrics 2009 stage IA, grade 1 to 2 endometrioid endometrial cancer managed with a levonorgestrel-releasing intra-uterine system for fertility preservation, co-morbidities, or refusal of hysterectomy after comprehensive counseling regarding risks and oncologic outcomes. A minimum follow-up of 6 months was required. Treatment response was assessed using serial hysteroscopic biopsies. Multi-variable logistic regression analysis was used to identify predictors of complete remission.

RESULTS

Forty-nine patients were included: 37 with atypical endometrial hyperplasia and 12 with endometrial cancer. Among the patients with cancer, 10 had grade 1 disease and 2 had grade 2 disease. Median follow-up was 2.6 years. The overall complete remission rate was 75.5% and was significantly higher in patients with atypical endometrial hyperplasia than in those with endometrial cancer (89.2% vs 33.3%). Focal lesions were associated with higher remission rates than diffuse endometrial involvement in univariate analysis (86.5% vs 42.0%, p <.01), but this association was not maintained in multi-variable analysis. A diagnosis of atypical endometrial hyperplasia independently predicted complete remission (adjusted odds ratio 17.4, 95% confidence interval 1.98 to 152, p =.009). No recurrences or severe adverse events were observed.

CONCLUSIONS

A levonorgestrel-releasing intra-uterine system is highly effective for atypical endometrial hyperplasia, with high complete remission rates. In low-grade endometrial cancer, lower response rates were observed, and the results should be interpreted cautiously given the small sample size. These findings support the levonorgestrel-releasing intra-uterine system as a conservative option for selected patients and emphasize the need for careful selection and close surveillance.