RECURRENCE, RE-OPERATION, AND PREGNANCY RATES AFTER SURGICALLY TREATED OVARIAN ENDOMETRIOMA IN A SINGLE INSTITUTION: LONG-TERM FOLLOW UP OF 756 WOMEN

Abstract

The aims of this study were to evaluate the cumulative recurrence, re-operation, and pregnancy rates after surgically treated ovarian endometrioma in a single institution for more than a 5-year follow up period. This was a retrospective chart review of the patients with ovarian endometrioma who underwent surgery between January 2008 and March 2016. Study subjects included premenopausal women with at least 5-years of follow-up. Exclusion criteria were patients with stage I or II ovarian endometrioma by revised American Society for Reproductive Medicine (rASRM) classification, those who underwent hysterectomy or bilateral oophorectomy, and presence of residual ovarian lesions on the first postoperative ultrasonography at 3-6 months. Recurrent ovarian endometrioma was defined as a new cystic mass measuring 20 mm or more on the ultrasonography. A total of 756 patients were recruited. The mean age was 31.8±6.3 years (median 31 years, range, 16-54 years) and the mean follow-up duration was 90.4±23.3 months (median 85.5 months, range, 60-155 months). Recurrent ovarian endometrioma was detected in 27.9% (211 of 756 patients), and re-operation was performed in 8.3% (63 of 756 patients). Total 29.9% (63 of 211 patients) with recurrent endometrioma was treated with repeated surgery. Using the Kaplan-Meier method, the cumulative recurrence rate at 24, 36, 60, and 120 months after surgical treatment of ovarian endometrioma was calculated as 5.9%, 8.7%, 15.5% and 37.8%, respectively. The cumulative re-operation rate at 24, 36, 60, and 120 months was 0.3%, 1.1%, 3.1% and 15.6%, respectively. After multivariate analyses, age ≤ 31 years (hazard ratio [HR]=2.108; 95% confidence interval [CI]=1.522-2.921; p<0.001), no subsequent pregnancy (HR=1.851; 95% CI=1.309-2.617, p<0.001), postoperative hormonal treatment ≤15 months (HR=2.869; 95% CI=2.088-3.941); p<0.001) were significant risk factors for recurrent ovarian endometrioma. Among the study patients, 316 (41.7%) women desired future pregnancy, and 171 of 316 (54.1%) were able to conceive and had uncomplicated delivery. Eighteen (5.7%) women experienced spontaneous abortion or ectopic pregnancy, and 36 (11.4%) women were either pregnant at the time of data collection or lost to follow up after confirming intrauterine pregnancy. Among the 316 patients who desired pregnancy, 91 (28.8%) failed to conceive. Considering the fact that longer postoperative hormonal treatment is the sole modifiable factor for recurrent ovarian endometrioma, we recommend long-term hormonal treatment until subsequent pregnancy, especially in younger age group.