Embolization of renal angiomyolipomata in patients with tuberous sclerosis complex
ABSTRACT Renal angiomyolipomata can reduce renal reserve and lead to renal insufficiency and failure. Angiomyolipomata often have abnormal vasculature, with aneurysms that can hemorrhage. Treatment of angiomyolipomata greater than 4 cm in diameter is suggested to decrease the risk for hemorrhage. Nephron-sparing procedures are critical in patients because of their limited renal reserve. Embolization has been used to treat these tumors, but there are limited studies examining efficacy. Our study examines the efficacy of selective embolization in decreasing tumor burden, preventing hemorrhage, and preserving renal function.
We conducted a retrospective study of 16 patients with 20 angiomyolipomata on 18 kidneys who underwent 18 transcatheter transarterial embolization procedures. Aneurysm number and size were documented and tumor volumes were measured before and after embolization. Preprocedure and follow-up renal function also were measured. Changes in angiomyolipoma volume and kidney function were assessed for significance by using paired t-test.
Before embolization, 7 angiomyolipomata had more than 5 aneurysms, 9 had 1 to 5 aneurysms, and 4 had no aneurysms, but showed tortuous dysmorphic arteries. Mean aneurysm size was 5 mm. In patients available for follow-up, 15 of 16 tumors had decreased in volume (mean decrease, 56.1%; P = 0.001). At an average of 40 months' follow-up, there have been no subsequent hemorrhages. Patients' decline in renal function was not significantly different from that expected because of the natural course of the disease.
Selective embolization decreases tumor size, prevents hemorrhage, and preserves kidney function in patients with tuberous sclerosis with renal angiomyolipomata.
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ABSTRACT: Objective To evaluate using of polyvinyl alcohol particle and N-butyl cyanoacrylate (NBCA)/lipiodol mixture for selective embolization of eight patients with ruptured renal angiomyolipomas (AMLs). Patients and methods From January 2006 to December 2012, eight patients underwent angiography and embolization of renal angiomyolipoma-associated hemorrhage. The patients were 7 women and one man, 22–52 years old. Only 2 patients had the sporadic form of angiomyolipoma and the other 6 patients had the tuberous sclerosis form. Two patients presented with hematuria, while the other 6 patients presented with perinephric bleed. Three patients were treated urgently, while the other 5 patients were scheduled for embolization 1–3 days after admission. The technical and clinical success, complications, rebleeding and the need for surgical intervention were documented. Results Angiography showed aneurysmal dilatation in 7 patients (88%). Twenty-five feeding arteries were embolized. Primary technical success rate was 62.5% and the clinical success rate was 100%. No major complications or deaths occurred during or after the procedures. Mean hospitalization was 5 (range 3–12) days. Secondary technical success rate was 100%. No tumor growth on the follow up CT and the mean size reduction was 41%. Conclusion Selective arterial embolization with polyvinyl alcohol particles and N-butyl cyanoacrylate/lipiodol mixture is an effective and safe treatment for patients with ruptured renal AMLs.09/2014; 45(3). DOI:10.1016/j.ejrnm.2014.05.006
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ABSTRACT: 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. 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. 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. 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. aEuro cent Selective arterial embolization is effective for angiomyolipoma devascularisation and volume reduction aEuro cent Volume reduction depends of initial volume and tissue composition of the tumour aEuro cent Selective arterial embolization is a low radiation treatment.European Radiology 06/2014; 24(8). DOI:10.1007/s00330-014-3244-4 · 4.34 Impact Factor
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ABSTRACT: Lymphangioleiomyomatosis (LAM), a multisystem disease affecting almost exclusively women, is characterized by cystic lung destruction and presents with dyspnea, recurrent pneumothoraxes, chylous effusions, lymphangioleiomyomas, and angiomyolipomas. It is caused by the proliferation of a cancer-like LAM cell that possesses a mutation in either the tuberous sclerosis complex (TSC)1 or TSC2 genes. This article reviews current therapies and new potential treatments that are currently undergoing investigation. The major development in the treatment of LAM is the discovery of two mammalian target of rapamycin (mTOR) inhibitors, sirolimus and everolimus, as effective drugs. However, inhibition of mTOR increases autophagy, which may lead to enhanced LAM cell survival. Use of autophagy inhibitors, for example, hydroxychloroquine, in combination with sirolimus is now the subject of an ongoing drug trial (SAIL trial). Another consequence of mTOR inhibition by sirolimus is an increase in Rho activity, resulting in reduced programmed cell death. From these data, the concept evolved that a combination of sirolimus with disruption of Rho activity with statins (e.g. simvastatin) may increase TSC-null cell death and reduce LAM cell survival. A combined trial of sirolimus with simvastatin is under investigation (SOS trial). Since LAM occurs primarily in women and TSC-null cell survival and tumor growth is promoted by estrogens, the inhibition of aromatase to block estrogen synthesis is currently undergoing study (TRAIL trial). Other targets, for example, estrogen receptors, mitogen-activated protein kinase inhibitors, vascular endothelial growth factor-D signaling pathway, and Src kinase, are also being studied in experimental model systems. As in the case of cancer, combination therapy may become the treatment of choice for LAM.