Outcomes of extended progestin therapy in atypical endometrial hyperplasia patients without an initial response to progestin: a retrospective study from two tertiary centers in Korea and Taiwan.

Objective: In this study, we evaluated the role of prolonged progestin treatment on atypical endometrial hyperplasia (AEH) patients who did not achieve complete regression (CR) after at least 3 months of progestin treatment. Possible prognostic factors predicting disease regression and recurrence were also assessed.

Methods: We retrospectively identified patients who had histologically confirmed persistent disease after at least 3 months of progestin treatment at two tertiary centers in Korea and Taiwan. Clinicopathologic factors and clinical outcomes were obtained from medical records. Logistic regression was used to analyze the relationship between covariates and the probability of CR and relapse.

Results: Fifty-two patients were included. Thirty-seven of 52 patients (71.2%) achieved CR after prolonged progestin treatment. Median time from starting progestin treatment to CR was 12.0 months. Daily administration of medroxyprogesterone acetate ≥200 mg or megestrol acetate ≥80 mg was associated with higher probability of regression. Nineteen of 37 patients (51.4%) experienced recurrence, with median time from CR to relapse of 15.0 months. Body mass index ≥27 was associated with higher relapse probability. Twelve of 16 patients with disease progression to endometrial carcinoma underwent surgery. The 12 cases had stage I tumors and lived without disease.

Conclusion: Extension of progestin treatment course is feasible for AEH patients without an initial response to progestin. Higher daily progestin dosage was associated with higher probability of CR, and obesity was associated with higher risk of relapse. The patients without an initial response to progestins and whose AEH progressed to endometrial carcinoma had good prognoses.