[Preventive and emergency embolization of angiomyolipomas: our experience]

Renal function, complications, and outcomes of a reduction in tumor size after transarterial embolization for renal angiomyolipomas: a meta-analysis

OBJECTIVE

The present study aimed to evaluate renal function, complications, and changes in tumor size after transarterial embolization for patients with renal angiomyolipomas.

METHODS

We performed a meta-analysis of transarterial embolization in patients with renal angiomyolipomas from January 1994 to April 2018. Endpoints of interest were the estimated glomerular filtration rate, serum creatinine levels, blood urea nitrogen levels, complications, and reduction of tumors.

RESULTS

A total of 30 studies comprising 653 patients were included. A total of 32.0% of patients were treated by urgent transarterial embolization for spontaneous ruptured renal angiomyolipomas. Other patients sought to relieve symptoms or received embolism prophylactically. The estimated glomerular filtration rate showed no significant difference between before and after embolization. In 363 patients with data on complications, post-embolization syndrome occurred most frequently (54.0%). Only 16 (4.4%) patients had major complications. The diameter of sporadic angiomyolipomas was reduced by a mean of 2.09 cm (95% confidence interval [CI], 0.73-3.45 cm; I2 = 29.3%) and they were reduced in size by 30.0% (95% CI, 16.0%-44.0%; I2 = 27.9%).

CONCLUSIONS

Transarterial embolization of renal angiomyolipomas affects renal function preservation, with a low complication rate. Transarterial embolization is useful for sporadic and tuberous sclerosis complex-related angiomyolipomas.

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

BACKGROUND

Angiomyolipoma (AML) is the most common renal benign tumor. Treatment should be considered for symptomatic patients or for those at risk for complications, especially retroperitoneal bleeding which is correlated to tumor size, grade of the angiogenic component and to the presence of tuberous sclerosis complex (TSC). This study reports our single-center experience with the use of selective arterial embolization (SAE) in the management of symptomatic and asymptomatic renal AMLs.

METHODS

In this retrospective mono-centric study, all demographic and imaging data, medical records, angiographic features, outpatient charts and follow-up visits of patients who underwent prophylactic or emergency SAE for AMLs between January 2005 and July 2016 were reviewed. Tumor size and treatment outcomes were assessed at baseline and after the procedure during follow-up. Computed tomography (CT), magnetic resonance imaging (MRI) or ultrasonography was used to evaluate AML shrinkage. Renal function was measured pre- and post-procedure.

RESULTS

Twenty-three patients (18 females, 5 males; median age, 45 years; range, 19-85 years) who underwent SAE either to treat bleeding AML (n=6) or as a prophylactic treatment (n=17) were included. Overall, 34 AMLs were embolized. TSC status was confirmed for 6 patients. Immediate technical success rate was 96% and 4 patients benefitted from an additional procedure. Major complications occurred in 3 patients and minor post-embolization syndrome (PES) in 14 patients. The mean AML size reduction rate was 26.2% after a mean follow-up was 20.5 months (range, 0.5-56 months), and only non-TSC status was significantly associated with better shrinkage of tumor (P=0.022). Intralesional aneurysms were significantly more frequent in patients with hemorrhagic presentation (P=0.008). There was no change in mean creatinine level after SAE.

CONCLUSIONS

SAE is a safe and effective technique to manage renal AMLs as a preventive treatment as well as in emergency setting, with significant reduction in tumor size during follow-up. A multidisciplinary approach remains fundamental, especially for TSC patients. In addition to size, the presence of intralesional aneurysms should be considered in any prophylactic treatment decision.

Long-term results of preventive embolization of renal angiomyolipomas: evaluation of predictive factors of volume decrease

OBJECTIVES

To evaluate the efficacy of selective arterial embolization (SAE) of angiomyolipomas based on the percentage volume reduction after embolization and to identify predictive factors of volume decrease.

METHODS

Patients receiving prophylactic SAE of renal angiomyolipomas were included retrospectively over 3 years. The volume change after SAE and haemorrhagic or surgical events were recorded. Initial tumour volume, percentage tumour fat content, mean tumour density, embolic agent used, number of angiomyolipomas and tuberous sclerosis disease were evaluated as predictive factors of volume decrease.

RESULTS

A total of 19 patients with 39 angiomyolipomas were included with median follow-up of 28 months (interquartile range 21-37 months). All treatments were technically successful (92% primary and 8% secondary). No distal bleeding or any increase in size or surgical nephrectomy after SAE was recorded. Mean volume reduction was 72% (±24%). Volumes before SAE (R(2) = 0.276; p = 0.001), percentage fat content (R(2) = 0.612; p < 0.0001) and mean angiomyolipoma density (R(2) = 0.536; p < 0.0001) were identified as predictive factors of volume decrease. In multivariate regression, only percentage fat content influenced volume decreases.

CONCLUSIONS

SAE is an efficient treatment for angiomyolipoma devascularisation and volume reduction. A significant reduction of volume is modulated by the initial volume and tissue composition of the tumour.

KEY POINTS

• Selective arterial embolization is effective for angiomyolipoma devascularisation and volume reduction • Volume reduction depends of initial volume and tissue composition of the tumour • Selective arterial embolization is a low radiation treatment.

Emergency embolization of actively bleeding renal angiomyolipoma in a patient of tuberous sclerosis

Renal angiomyolipoma is a benign hamartomatous lesion which contains varying proportions of abnormal blood vessels along with muscle and fat component. Tuberous sclerosis predisposes to angiomyolipoma, and when associated, the lesion is often large with increased risk of hemorrhage and complications. When this occurs, transarterial embolization and surgery are the treatment options. Such a patient presented to us with acute onset of symptoms, and on account of severe anemia with active bleeding, transarterial embolization was performed. This was followed by elective nephrectomy without any complications. We present the imaging aspects of tuberous sclerosis and emphasize role of interventional radiology in this case.

Renal angiomyolipoma with Fatty thrombus extending to the right atrium: an exceptional presentation

This paper reports the case of 34-year-old woman who presented with bilateral renal angiomyolipomas (AMLs). On the right side, there was a large AML with a fatty thrombus extending to the right atrium. The treatment consisted of right nephrectomy and complete thrombectomy with extracorporeal circulation and right atriotomy. Postoperatively, the patient was septic and died on postoperative day 7 because of septic shock.