Aspiration and sclerotherapy of symptomatic simple renal cysts: Value of two injections of a sclerosing agent

OBJECTIVE. The purpose of our study was to determine whether two injections of sclerosant were more effective than a single injection in treating symptomatic simple renal cysts. SUBJECTS AND METHODS. We reviewed our results obtained by simple aspiration, by aspiration and a single sclerosant injection, and by aspiration followed by two injections of sclerosing agent over 48 hr. We used 95% alcohol because of its capacity to safely sclerose the epithelial lining of renal cyst walls without damaging the renal parenchyma. After 1-3 rain of contact with the alcohol, the epithelial cells lining the cyst become fixed and nonviable; the cyst capsule is penetrated only after 4-12 hr. Longer contact of alcohol with the epithelial cell lining should theoretically result in the nonviability of more epithelial cells and therefore in a lower recurrence rate of cysts after aspiration and sclerotherapy. Our subjects were 46 patients, 30 men and 16 women, treated over a 13-year period. They ranged in age from 38 to 75 years old (mean age, 47 years). Fifty-two cysts were treated. Twenty patients (20 cysts) had simple aspiration only, 15 patients (19 cysts) had a single injection of sclerosant after aspiration, and 11 patients (13 cysts) had two sclerosant injections after aspiration. RESULTS. Of the 20 patients who had simple aspiration only, 16 cysts had recurred after 2 years. In the single injection group of patients, we found six recurrences after 2 years. No recurrence has occurred in the group of patients who had two sclerosant injections after aspiration. CONCLUSION. Our findings suggest that the results of treating symptomatic simple renal cysts are better in terms of recurrence with two successive injections of 95% alcohol, probably because of the nonviability of more epithelial cells lining the cyst as a result of a longer period of contact with the alcohol. Our sonographic finding of pseudotumors at the sites of previously aspirated giant cysts in two patients is recorded.