Prediction of regression and relapse of endometrial hyperplasia with conservative therapy.

OBJECTIVE To identify predictors and to estimate their prognostic accuracy for regression and relapse of endometrial hyperplasia treated with levonorgestrel-releasing intrauterine system or oral progestogens. METHODS This was a cohort study of women treated with levonorgestrel-releasing intrauterine system or oral progestogens for complex hyperplasia or atypical complex hyperplasia for women wishing to preserve their fertility or those who were unfit for surgery. Hazard ratios (HRs) with the Cox proportional hazards model and Kaplan-Meier survival estimates for independent predictors were calculated. RESULTS Regression was evaluated in 344 women over a 12-year period, with a median follow-up of 58.8 months (interquartile range 38.4-96.4, range 12-148.2) for levonorgestrel-releasing intrauterine system compared with 95.1 months (interquartile range 41.6-124.6, range 13.2-162) for oral progestogens. In women treated with levonorgestrel-releasing intrauterine system for complex hyperplasia, we found that 221 women regressed (96.5%, 221/229) and body mass index (BMI) 35 or higher was associated with failure to regress (HR 5.51, 95% confidence interval [CI] 1.05-28.87; P=.043). Relapse was evaluated in 219 women over a 9-year period, with median follow-up of 67 months (interquartile range 50.4-103.5, range 14.5-146.4) for levonorgestrel-releasing intrauterine system and 96.8 months (interquartile range 62.3-122, range 6-151.5) for oral progestogens. In women treated with levonorgestrel-releasing intrauterine system for complex hyperplasia, we found that 18 women experienced relapse (12.7%, 18/142) and BMI 35 or higher was found to be a strong independent predictor of relapsed endometrial hyperplasia (HR 18.93, 95% CI 3.93-91.15; P<.001). Only 3.3% of women with complex hyperplasia treated with levonorgestrel-releasing intrauterine system and with BMI less than 35 experienced relapse during long-term follow-up compared with 32.6% of women with BMI 35 or higher. CONCLUSION Body mass index 35 or higher is strongly associated with failure to regress and relapse of complex hyperplasia treated with levonorgestrel-releasing intrauterine system.