Introduction: We report a rare case of a huge bleeding renal angiomyolipoma (AML) with multiple aneurysms treated with staged transcatheter arterial embolization (TAE) using N-butyl cyanoacrylate (NBCA) and additional microcoils. After three TAEs, we succeeded in managing hemorrhage and aneurysms. We also gained 50% tumor regression with preserved viable renal parenchyma.

Case Report: A 37-year-old female was admitted at our emergency center due to retroperitoneal hemorrhage. Computed tomography (CT) revealed a huge right renal AML of 26 cm in diameter with multiple aneurysms bleeding in the retroperitoneal space. An emergent TAE was performed, and we managed bleeding by using NBCA instantly, but large aneurysms in the tumor vessel remained. We planned staged TAE for the aneurysms left at the proximal side of the right renal artery. We used detachable coils as embolizing agents after NBCA, and the second TAE was completed uneventfully. However, follow-up CT examination revealed another hemorrhage, the third TAE was performed. An arteriogram of the right renal artery revealed tumor stain from other branches of the renal artery, which we did not embolize before. These branches were embolized completely using NBCA. Follow-up CT examination showed the aneurysms stopped and a tumor regression of about 50% in diameter.

Conclusion: TAE using NBCA is very useful for treating renal AML because it can provide promising effects and low complications with a minimally invasive technique. We choose NBCA as a first-choice embolizing agent for treating renal AML even if it is huge and has aneurysm with staged TAE.

Keywords: Aneurysm, Embolization, Hemorrhage, NBCA, Renal angiomyolipoma