Risk factors for the recurrence in patients with early endometrioid endometrial cancer achieving complete remission for fertility-sparing hormonal treatment.

Objective: This study aimed to assess the recurrence risk factors in patients with early-stage endometrioid endometrial cancer (EC) who achieved a complete response (CR) through fertility-sparing hormonal treatment (FST).

Methods: We retrospectively analyzed patients who received FST for presumed stage IA and grade 1 endometrioid EC at two institutions. Medroxyprogesterone (MPA)- and levonorgestrel-releasing intrauterine devices (LNG-IUD) were used concurrently. Maintenance therapy involved maintaining the LNG-IUDs in situ for those who did not attempt to conceive immediately after achieving CR. Cox regression analysis was used to identify clinicopathological variables for recurrence-free survival (RFS) following CR.

Results: Among 178 patients with endometrioid EC who received FST, 142 (79.8 %) achieved CR. The median time to achieve CR and the median FST duration were 10 months (range 1-34) and 14 months (range 3-49), respectively. During the median follow-up period of 44 months (range 6-143), 59.9 % (85/142) of patients had recurrence, with a median RFS of 14 months (range 1-123) after CR. In multivariable analysis, age > 35-years (hazard ratio (HR) 1.892, 95 % confidence interval (CI) 1.224-2.923; P < 0.05) and pregnancy after the first CR (HR 0.203, 95 % CI 0.093-0.444; P < 0.05) were significantly associated with RFS.

Conclusions: Older age and non-pregnancy status may be risk factors for recurrence after CR. Therefore, patients with these conditions should undergo stringent follow-up, including imaging and histological examinations, to detect recurrence after CR.