Transarterial Embolization of Angiomyolipoma: A Systematic Review.

Background: Transarterial embolization is increasingly used in the management of renal angiomyolipoma. The level of evidence establishing the safety and efficacy of transarterial embolization has not increased in parallel.

Methods: Using the MOOSE (Meta-analysis Of Observational Studies in Epidemiology) criteria a systematic review of transarterial embolization of angiomyolipoma was performed to establish procedural safety and efficacy. A MEDLINE® PubMed® search revealed 1,739 publications, of which 31 studies met eligibility criteria.

Results: A total of 524 cases of transarterial embolization of angiomyolipoma were included in analysis. Self-limiting post-embolization syndrome developed following 35.9% of embolizations and further morbidity developed in 6.9%. No procedural mortality was reported. At a mean followup of 39 months the mean size reduction was 3.4 cm (-38.3% of angiomyolipoma diameter). Unplanned repeat embolization or surgery was required in 20.9% of cases during this period. The most frequent indications for repeat procedures included angiomyolipoma revascularization in 30.0% of cases, unchanged or increasing size in 22.6%, refractory or recurring symptoms in 16.7% and representation with acute retroperitoneal hemorrhage in 14.3%. Treatment included a combination of 2 or more embolic agents in 46.8% of cases, ethanol monotherapy in 41.7%, coil monotherapy in 6.2% and foam or microparticle monotherapy in 5.2%.

Conclusions: Transarterial embolization of angiomyolipoma demonstrates low rates of mortality and serious complications. Re-treatment rates and size reduction at a mean followup of 39 months are presented. Longitudinal data assessing long-term size reduction and re-treatment rates are lacking. Recommendations guiding the indications for transarterial embolization and clear followup require further longitudinal data.