Endometriosis of the Appendix: When to Predict and How to Manage—A Multivariate Analysis of 1935 Endometriosis Cases

Study Objective: To evaluate appendiceal endometriosis (AE) prevalence and risk factors in endometriotic patients submitted to surgery. Design: A retrospective cohort study. Setting: A tertiary level referral center, university hospital. Patients: One thousand nine hundred thirty-five consecutive patients who underwent surgical removal for symptomatic endometriosis. Interventions: Electronic medical records of patients submitted to surgery over a 12-year period were reviewed. We assessed any correlation between demographic, clinical, and surgical variables and AE. In our center, appendectomy was performed using a selective approach. Appendix removal was performed in case of gross abnormalities of the organ, such as enlargement, dilation, tortuosity, or discoloration of the organ or the presence of suspected endometriotic implants. Measurements and Main Results: AE prevalence was 2.6% (50/1935), with only 1 false-positive case at gross intraoperative evaluation. In multivariate analysis using a stepwise logistic regression model, independent risk factors for AE were adenomyosis (adjusted odds ratio [aOR] = 2.48; 95% confidence interval [CI], 1.32–4.68), right endometrioma (aOR = 8.03; 95% CI, 4.08–15.80), right endometrioma ≥5 cm (aOR = 13.90; 95% CI, 6.63–29.15), bladder endometriosis (aOR = 2.05; 95% CI, 1.05–3.99), deep posterior pelvic endometriosis (aOR = 5.79; 95% CI, 2.82–11.90), left deep lateral pelvic endometriosis (aOR = 2.11; 95% CI, 1.10–4.02), and ileocecal involvement (aOR = 12.51; 95% CI, 2.07–75.75). Conclusion: Among patients with endometriosis submitted to surgery, AE was observed in 2.6%, and it was associated with adenomyosis, large right endometrioma, bladder endometriosis, deep posterior pelvic endometriosis, left deep lateral pelvic endometriosis, and ileocecal involvement.