The value of the AAGL staging system for predicting recurrence after conservative surgery for ovarian endometriomas

Abstract

Background: Ovarian endometrioma (OMA) is the most prevalent form of endometriosis. Conservative surgical management of the condition is associated with a relatively high recurrence rate, the degree of which is potentially linked to disease severity. Recently, the American Association of Gynecologic Laparoscopists (AAGL) staging system was developed to reflect the severity of endometriosis and the surgical complexity. However, its predictive value for recurrence following conservative surgery in OMA patients remains unestablished.

Methods: To evaluate the predictive value of the AAGL staging system for recurrence following conservative surgery in OMA patients. A retrospective cohort study was conducted at Fuzhou University Affiliated Provincial Hospital and included patients who were diagnosed with OMA and underwent conservative surgery (ovarian cystectomy) between January 1, 2018, and December 31, 2022. All patients were assessed with the AAGL staging system and the revised American Society for Reproductive Medicine (r-ASRM) staging system according to the intraoperative findings. The primary outcome was the postoperative recurrence rate. Secondary outcomes included the consistency between the AAGL and r-ASRM systems in assessing patient condition and the correlation between the AAGL stage and surgical complexity as defined by the endometriosis surgery complexity score. Maximally selected rank statistics were used to determine the optimal AAGL score threshold and assess the correlation between the AAGL score and recurrence risk. Landmark analysis was used to assess the predictive value of the AAGL staging system for recurrence following conservative surgical treatment for OMA. Kappa statistics were used to analyse the consistency between the AAGL and r-ASRM staging systems. Kendall's coefficient of concordance was used to assess the relationships between the staging systems and the surgical complexity.

Results: A total of 299 patients with OMA were included in the study. A total of 49 patients (16.4%) experienced postoperative recurrence, whereas 250 patients (83.6%) did not. The median postoperative follow-up duration was 39.6 months. The cumulative recurrence rates at 12, 24, 36, 48, and 60 months post-surgery were 2.4%, 7.0%, 13.1%, 23.3%, and 29.6%, respectively. Patients with an AAGL score > 16 had a significantly greater risk of recurrence following conservative surgery than those with an AAGL score ≤ 16 (P = 0.022). At 36 months post-conservative surgery and beyond, patients with an AAGL score > 16 presented a significantly higher recurrence rate than did those with a score ≤ 16 (P = 0.043). A comparison of the AAGL and r-ASRM systems in all patients revealed poor agreement between the two in terms of disease stage (weighted κ = 0.243). Furthermore, the AAGL staging system demonstrated stronger concordance with the surgical complexity scale than the r-ASRM system did (Kendall W coefficient = 0.613, P = 0.005; Kendall W coefficient = 0.552, P = 0.106, respectively).

Conclusions: The cumulative recurrence rate following conservative surgery for OMA patients progressively increased over time. The AAGL staging system was useful for predicting recurrence in OMA patients following conservative surgery, particularly starting at 36 months post-surgery. The AAGL staging system offers an improved assessment of surgical complexity in OMA patients.

Keywords: AAGL staging system; Ovarian cystectomy; Ovarian endometrioma; Recurrence; Risk factors.