Ultrasound-guided aspiration of adnexal cysts with a low risk of malignancy: is it a recommendable option?

Objectives: The purpose of this study was to establish the viability of ultrasound (US)-guided adnexal cyst aspiration and identify a target group in which this procedure would be advisable.

Methods: A prospective cohort of 96 women with a low risk of malignant adnexal cysts was studied between 2002 and 2009, using recurrence after the procedure as the primary outcome measure. All procedures were performed on an outpatient basis without anesthesia. Patients were followed by US imaging at 6, 12, 24, 48, and 72 months. Potential risk factors for recurrence (menopausal status, previous hysterectomy, symptoms, US pattern, cyst diameter, and aspirated fluid volume and color) were analyzed by multivariate logistic regression. The association between recurrence and cyst size was calculated by Kaplan-Meier curves.

Results: The median diameter of the cysts was 61 (range, 30-150) mm. Multivariate logistic regression analysis showed that an increased risk of recurrence was associated with a cyst diameter of greater than 70 mm (odds ratio, 4.2; 95% confidence interval, 1.2-14.1) and the presence of symptoms (odds ratio, 5.03; 95% confidence interval, 1.02-24.6). The median follow-up time was 24 (range, 2-78) months. Surgery was avoided in 64 patients (73.6%). Full cyst recurrence was observed in 34 patients (39.0%).

Conclusions: Ultrasound-guided aspiration is a viable alternative to surgery for treatment of adnexal cysts with a low risk of malignancy, especially when the cyst diameter is less than 70 mm.