New Trends and Evidence for the Management of Renal Angiomyolipoma

Abstract

Treatment of renal angiomyolipoma (AML) seeks to reduce related complications and preserve kidney function. The purpose of this article was to perform an updated literature review on the diagnosis, therapeutic options, and criteria for invasive intervention in patients with renal AML. Computerized tomography is the standard diagnostic method for renal AML, while definitive diagnosis is made by histopathology. The management of choice in most cases is active surveillance (AS), with a clinical and imaging follow-up protocol. In high-risk cases, therapeutic management should be considered, with alternatives such as selective arterial embolization (SAE), nephron-sparing surgery (NSS), and mTOR inhibitors in selected patients. Renal AML in women of childbearing age, those with growth >0.25 cm/year, intralesional aneurysms >5 mm, and clinically significant symptoms may qualify for active treatment. Despite the limitations derived from the available evidence, it is possible to consider SAE, NSS, and the use of mTOR inhibitors as management alternatives for selected patients.

Renal angiomyolipoma: Beyond size criteria for predicting rupture

“…7 Since publication by Oesterling et al, 7 other studies have confirmed the correlation between tumour size and risk of haemorrhage. 8,9 In the pursuit of advancing clinical decisionmaking past the 'rule of four', Yamakao et al 11 demonstrated a significant relationship between tumour size, aneurysm size and spontaneous rupture in their series of 23 patients. 11 This study of 27 treated AMLs contributes to extending the body of evidence for the management of AMLs.…”

“…Historically, the main imaging factor utilised for predicting AML rupture, and therefore selecting tumours for treatment, has been tumour size 7 . Since publication by Oesterling et al ., 7 other studies have confirmed the correlation between tumour size and risk of haemorrhage 8,9 . In the pursuit of advancing clinical decision‐making past the ‘rule of four’, Yamakao et al 11 .…”

“…Numerous recent studies and guidelines have attempted to refine when to intervene on AML past this traditional 'rule of four', including considerations such as lesion imaging characteristics, change over time and patient symptoms. [8][9][10] Yamakao et al 11 evaluated the relationship between tumour size, intratumoural aneurysm formation and spontaneous rupture in renal AML. From their analysis of 29 tumours in 23 patients, they concluded that aneurysm size had greater specificity for AML rupture than tumour size.…”

“…A 4‐cm cut‐off was suggested for lesion size requiring management, with this size cut‐off still incorporated into treatment decision‐making nearly four decades later. Numerous recent studies and guidelines have attempted to refine when to intervene on AML past this traditional ‘rule of four’, including considerations such as lesion imaging characteristics, change over time and patient symptoms 8–10 …”

Is Size All That Matters? New Predictors of Complications and Bleeding in Renal Angiomyolipoma

“…15 Growth rate of >0.25cm/year, the presence of TSC, symptoms (pain or bleeding) have all been identified as indications for active treatment of AMLs. 1,3,16 Active surveillance has been identified as a possible management option for AMLs >4cm with literature highlighting that up to 92% of untreated AMLs irrespective of size had not grown and only 5.6% required intervention. 1 The risk of spontaneous and life-threatening bleeding has been recognized in approximately 2.2% of patients undergoing active surveillance.…”