Maintenance Therapy for Preventing Endometrioma Recurrence after Endometriosis Resection Surgery – A Systematic Review and Network Meta-analysis

To evaluate the efficacy of different hormone therapies in preventing postoperative endometrioma recurrence.The MEDLINE, COCHRANE, and Embase electronic databases were searched from inception to 30 April 2021.Randomized controlled trials (RCTs) or cohort studies including reproductive age women with endometriosis undergoing ovarian cystectomy or excision of endometriotic lesions compared the effects of postoperative adjuvant therapy (gonadotropin-releasing hormone agonist [GnRHa]) and postoperative maintenance hormone interventions for more than 1 year (i.e., oral contraceptive pills [OCPs], dienogest [DNG], levonorgestrel-releasing intrauterine system [LNGIUS]) on endometrioma recurrence.Data collection and analysis of the data were independently performed 2 two reviewers. A total of 11 studies were included, of which 2 were RCTs, and 9 were cohort studies. There were 2394 patients with 6 interventions (cases: 1665, 69.6%) and expectant management (cases: 729, 30.4%). Relative treatment effects were estimated using network meta-analysis and ranked in descending order. The clinical effectiveness of these drugs (vs expectant management) was as follows: GnRHa plus DNG (odds ratio [OR], 0.04; 95% confidence interval [CI], 0.01-0.27), surface under the cumulative ranking (SUCRA) = 94.0; DNG (OR, 0.11; 95% CI, 0.04-0.32), SUCRA = 69.7; GnRHa plus OCP (OR, 0.12; 95% CI, 0.02-0.64), SUCRA = 63.4; GnRHa plus LNGIUS (OR, 0.13; 95% CI, 0.03-0.66), SUCRA = 59.4; and OCP (OR, 0.21; 95% CI, 0.13-0.36), SUCRA = 43.6. The effectiveness of GnRHa (OR, 0.47; 95% CI, 0.12-1.89), SUCRA = 17.3 was not significantly different from that of controls.In network meta-analysis, combined postoperative adjuvant therapy and longer maintenance hormone treatment are better than a single agent in preventing postoperative endometrioma recurrence. GnRHa plus DNG maintenance treatment might be the most effective intervention. Large-scale RCTs of these agents are still required.