Optimal timing for hepatic cyst intervention: Predictive factors for complete resolution after ethanol sclerotherapy

Background and Objectives: The optimal timing of ethanol sclerotherapy and predictors of complete resolution (CR) in patients with symptomatic hepatic cysts remain unclear. This study aimed to identify clinical and procedural predictors of CR and to determine a volume-based threshold that may guide patient selection. Methods: We retrospectively analyzed 307 patients who underwent percutaneous catheter drainage–guided or EUS-guided ethanol sclerotherapy between 2003 and 2023. CR was defined as <5% of baseline cyst volume. Receiver operating characteristic analysis identified a volume threshold for CR, and multivariable logistic regression was used to determine independent predictors. Results: CR was achieved in 54.4% of patients during a mean follow-up of 24.7 ± 21.1 months. An initial cyst volume of 233 mL (≈7–8 cm in diameter) was identified by receiver operating characteristic analysis as a threshold associated with CR (area under the curve 0.626; sensitivity 50.9%; specificity 75.0%). CR rates were significantly higher in cysts <233 mL than in larger cysts (70.6% vs. 44.1%, P < 0.001). In multivariable analysis, cyst volume ≥233 mL (adjusted odds ratio [aOR] 0.27, 95% confidence interval [CI] 0.15–0.48) and elevated alanine aminotransferase >30 U/L (aOR 0.16, 95% CI 0.05–0.50) were independently associated with nonresolution, as was diabetes mellitus (aOR 0.12, 95% CI 0.02–0.62), a finding requiring external validation given the small diabetic subgroup ( n = 11). Treatment modality (EUS vs . percutaneous catheter drainage) was not associated with treatment success ( P = 0.678). Conclusion: Initial hepatic cyst volume is an important factor influencing treatment outcome. The 233 mL threshold may inform the timing of intervention alongside symptoms and patient-specific factors.