Patterns of renal angiomyolipoma regression post embolisation on medium- to long-term follow-up

Abstract

Results: 13 patients underwent 16 episodes of embolisation. Coils were used as the primary embolisation material in 10 episodes and microspheres in 6 episodes. The size reduction rate highly correlated on CT followup between the two groups, with 25.6% vs 22.7% reduction at 12 months, 27.5% vs 25.1% at 24 months, 35.0% vs 33.0% at 36 months and 35.0% vs 36.8% at 48 months. During follow-up, all tumours reduced in size with one patient requiring subsequent embolisation whose tumour reduced by only 6.5% after 1 year and subsequently exhibited regrowth after 4 years. Two patients presented with rebleeding and underwent repeat embolisation. Our overall retreatment rate (23%) is well within the literature range (up to 37%). None of the patients underwent surgery. Conclusion:The majority of AML shrinkage occurs within the first year following embolisation and appears to plateau after 3 years, which could have an impact on follow-up strategy. The percentage reduction at 1 year may reflect the long-term effect of embolisation with tumours demonstrating minor size reduction more likely to relapse at long-term follow-up. Embolisation of renal AML produces durable long-term results regardless of the choice of embolic agent. Advances in knowledge:These findings provide information to guide CT follow-up of renal AML post embolisation.

Selective arterial embolization of symptomatic and asymptomatic renal angiomyolipomas: a retrospective study of safety, outcomes and tumor size reduction

“…However, no patients were lost during follow-up in this study. should not impact the findings of our study since the majority of AMLs shrinkage occurs within the first years following SAE (79). This was confirmed for the last two patients of our series with only short term followup images available; the first one presented a 8% and 9% tumors shrinkage 1 month after treatment and the second an impressive 48% decreased 2 months after embolization.…”

Selective Arterial Embolization of Giant Renal Angiomyolipoma Associated with Tuberous Sclerosis Complex Using Particular and Liquid Embolic Agents

“…Tumors over 4 cm often experience hemorrhage and internal tumaro growth. The main indications for treatment are abdominal pain, internal tumor growth, retroperitoneal hemorrhage, and gross hematuria [2,3,7].…”

“…Selective nephron-sparing surgery is the gold standard if radiological diagnosis is certain. However, radical nephrectomy should be the procedure of choice if malignancy is suspected [1,3,7]. Surgery allows the complete resection of the tumor and pathologic confirmation.…”

“…Blood vessels within AMLs are abnormal and have no internal elastic lamina and form aneurysms and rupture [7]. Therefore, the selective embolization of AML is aimed at occluding these abnormal vessels and the optimal sparing of the normal renal parenchyma to maintain the maximal renal function [2,3,6].…”

“…Particular agents, such as PVA or embosphere, are the most commonly used in the embolization of AML. Particular embolization was commonly performed with a combination of 350-to 500-mm PVA particles to occlude the distal vascular bed followed by coils to block the arterial inflow and prevent the retrograde filling of the aneurysm and abnormal tumor vessels reference [7]. Coils should be avoided because they only provide proximal vessel occlusion, which may form collaterals around or at the distal level of occlusion, further making embolization difficult or impossible [3][4][5][6].…”