Abstract

Objective: To evaluate the effectiveness of single-session ethanol sclerotherapy in the treatment of symptomatic simple renal cysts.

Materials and methods: Between March 2006 and June 2011, 42 consecutive patients with 45 symptomatic renal cysts were treated with percutaneous aspiration and ethanol sclerotherapy. The volume of the cyst fluid ranged from 75 to 650 mL (mean 220 mL), and the cysts were categorized into three groups: <150 mL, 150-300 mL, and >300 mL. The cysts were aspirated under local anesthesia with ultrasound guidance using an 18-gauge 20 cm spinal puncture needle. After near-total cyst aspiration, volumes of 25 mL, 50 mL, and 75 mL of an ethanol sclerosing agent were used in the three cyst groups, respectively. The patients were reassessed at 1, 3, and 6 months. 

Results: The procedure was technically feasible in all of the patients. The final assessment at 6 months showed that, of the 45 cysts treated, there was a complete response (symptomatic with complete cyst resolution) in 33 (73%) cysts and a partial response in 10 (22%); the procedure was unsuccessful for 2 (4%) cysts.  There was a correlation between the initial cyst volume and the response to treatment. There were no major complications related to the procedure. Minor complications, including pain, fever, hematuria, and small perinephric hematoma were observed in 11 (26%) patients and were managed conservatively.

Conclusion: The treatment of symptomatic simple renal cysts using ethanol sclerotherapy under ultrasound guidance is a simple, safe, minimally invasive, and cost-effective outpatient procedure with satisfactory short- and mid-term results.  The procedure can be performed with good efficiency and low morbidity, particularly in moderately sized cysts (<300 mL) and therefore should be considered as a feasible therapeutic option for the treatment of symptomatic simple renal cortical cysts. However, a longer follow-up period is needed to assess the long-term results of this procedure.