Renal angiomyolipoma selective arterial embolization: Australian tertiary centre experience over 10 years

The purpose of this study is to evaluate the patient selection methods, treatment outcomes, complications, clinical and radiological follow-up after renal angiomyolipoma (AML) treatment with selective arterial embolization (SAE) in an Australian metropolitan tertiary centre.

This study presents a retrospective single-centre review of patients' medical records who underwent SAE for renal AML during the period of 1st January 2012 and 1st January 2023.

A total of 32 SAE procedures for renal AML occurred during the study period. Three episodes were classified as emergency cases [9.38%] and the remaining 29 were treated electively. Mean AML size pre-treatment was 69.45 mm (range = 33-177; SD = 31.69). All AMLs demonstrated hyper-vascularity on contrast-enhanced cross-sectional imaging (arterial-phase enhancement characteristics and/or prominent tortuous feeding vessels) [n = 32; 100%] or an intralesional aneurysm or pseudoaneurysm [n = 12; 42.85%]. Periprocedural complications [n = 3; 9.38%] included: one intralesional haemorrhage after embolization, one vascular access site complication, and one lipiduria-associated urinary tract infection. No patients suffered a life-threatening complication, non-target embolization, deterioration in renal function or death following SAE. Re-treatment with SAE was performed in only three patients [10.71%]. Hospital mean length of stay was 1.58 days. Median durations of clinical and radiological follow-up post-treatment were 493 days (range = 104-1645) and 501 days (range = 35-1774), respectively. Follow-up imaging revealed AML total size reduction in all cases [mean = -17.17 mm; -26.51%] and 50% had obliteration of lesion hyper-vascularity after one episode of SAE. Outpatient clinical follow-up signifies that none of the patients included in the study have re-presented with lesion haemorrhage after successful SAE.

In this study, renal AMLs were treated safely with a high degree of success by using SAE, and there were very low rates of periprocedural complications. Follow-up of patients after SAE treatment of renal AML should include both radiological (assessment for reduction in lesion vascularity and size) and clinical review in an outpatient clinic setting (either by an interventional radiologist or urologist).