Efficacy of medroxyprogesterone acetate treatment and retreatment for atypical endometrial hyperplasia and endometrial cancer

Aim: Medroxyprogesterone acetate (MPA) is used to preserve fertility in patients with Grade 1 endometrial cancer without myometrial invasion (G1EA) and those with atypical endometrial hyperplasia (AEH). However, the efficacy of retreatment with MPA has not been sufficiently established for patients who experience recurrence but wish to retain their fertility. This study aimed to show the effectiveness of MPA treatment and retreatment for AEH and G1EA. Methods: A total of 39 patients received MPA treatment between 2005 and 2015, including nine with G1EA and 30 with AEH. The patients received high-dose (600 mg/day) MPA for 26 weeks. If a complete response was not achieved, MPA treatment was continued. After complete remission, if there was a recurrence, the patient was offered a choice of a hysterectomy or retreatment with MPA. The gynecologic and obstetric outcomes were retrospectively analyzed. Results: The median age was 34 years, and the median body mass index was 23.3 kg/m². The median follow-up period was 52 months. Complete response rates for the initial treatment were 89% for G1EA and 93% for AEH. Recurrence occurred in 88% of patients with G1EA (7/8) and 50% of those with AEH (14/28). Seven patients with G1EA and 11 with AEH received MPA retreatment, and 100% and 92% of these achieved a complete response. During the study period, a total of 14 pregnancies were recorded with 10 live births. Conclusion: MPA can be effective for G1EA and AEH treatment even when they recur.