Elective and Emergency Renal Angiomyolipoma Embolization with Ethylene Vinyl Alcohol Copolymer: Feasibility and Initial Experience

Purpose: To report preliminary experience with angiomyolipoma (AML) transcatheter arterial embolization using ethylene vinyl alcohol (EVOH) copolymer liquid embolic agent.

Materials And Methods: Embolization was performed in 22 consecutive patients (mean age, 53.5 y; 16 women and 6 men) for symptomatic AMLs or AMLs > 4 cm. Mean AML size before treatment was 7 cm (range, 3.5-13 cm). Superselective embolization of all lesions using microcatheters was performed; EVOH copolymer was the only embolic agent used. Data collected included volume of EVOH copolymer used, AML size before and after treatment, bleeding control, rebleeding, renal function, and complications.

Results: Twenty-seven embolizations were performed for 25 AMLs. In 3 patients, embolization of 2 different AMLs was performed. A mean volume of 2.5 mL (range, 1-8 mL) of 6% EVOH copolymer was administered per lesion. Of embolizations, 17 (63%) were elective, and 10 (37%) were urgent. For urgent cases, primary and secondary bleeding control rates were 80% and 100%, respectively. Two urgent embolizations had early rebleeding from different previously treated vessels and a successful second embolization was performed. Mean follow-up time was 37.7 months (range, 5-124 months). Rate of postembolization syndrome was 18.5%. Mean size reduction of 45.7% ± 21.5 over the maximum length of the AML before treatment was achieved. No AML regrowth occurred during follow-up. Minor and major complication rates were 7.4% and 0%, respectively. No rebleeding and no renal function impairment occurred during follow-up.

Conclusions: AML embolization with EVOH copolymer is feasible, safe, and effective. EVOH copolymer could be another embolic option for AML treatment.