EUS-guided ethanol versus saline solution lavage for pancreatic cysts: a randomized, double-blind study

Background Surgery for pancreatic cysts is associated with significant morbidity. A pilot study previously demonstrated the safety of EUS-guided ethanol lavage of pancreatic cysts. Objective To determine whether EUS-guided ethanol lavage would decrease pancreatic cyst size more than saline solution lavage. Design Prospective, multicenter, randomized trial. Setting Two tertiary referral hospitals in the United States. Patients Patients referred for EUS with a 1- to 5-cm unilocular pancreatic cyst were randomized to blinded ethanol or saline solution lavage. Three months later, the cyst diameter was remeasured by EUS, and a second unblinded ethanol lavage was performed. Interventions EUS-guided pancreatic cyst lavage. Main Outcome Measurements Cyst ablation based on size changes from follow-up EUS, CT, and histology of resected specimens. Results Of 58 patients randomized, 16 were excluded and 42 underwent initial ethanol (n = 25) or saline solution (n = 17) lavage. Ethanol lavage resulted in a greater mean percentage of decrease in cyst surface area (−42.9; 95% CI, −58.4 to −27.4) compared with saline solution alone (–11.4; 95% CI, −25.0 to 2.2; P = .009). Nineteen (76.0%) of 25 and 14 (82.3%) of 17 patients randomized to ethanol and saline solution, respectively, underwent a second ethanol lavage. A follow-up CT scan demonstrated resolution in 12 (33.3%) of 36 cysts. Histology of 4 resected cysts demonstrated epithelial ablation ranging from 0% (saline solution alone) to 50% to 100% (1 or 2 ethanol lavages). Complication rates were similar in all groups. Limitation Short-term follow-up. Conclusions EUS-guided ethanol lavage results in a greater decrease in pancreatic cyst size compared with saline solution lavage with a similar safety profile. Overall CT-defined complete pancreatic cyst ablation was 33.3%. (This study is registered at ClinicalTrials.gov, identifier NCT00233038.)