Renal angiomyolipoma

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Renal angiomyolipomas (AML) are a type of benign renal neoplasm encountered both sporadically and as part of a phakomatosis, most commonly tuberous sclerosis. They are considered one of a number of ~~tumours~~tumors with perivascular epitheloid cellular differentiation (PEComas) and are composed of vascular, smooth muscle and fat elements. They can spontaneously ~~haemorrhage~~hemorrhage, which may be fatal. AMLs usually have characteristic radiographic appearances.

Epidemiology

Angiomyolipomas are the most common benign solid renal lesion and also the most common fat-containing lesion of the kidneys. The majority of angiomyolipomas are sporadic (80%) and are typically identified in adults (mean age of presentation 43 years), with a strong female predilection (F:M of 4:1) ^7,9.

The remaining 20% are seen in association with phakomatoses, the vast majority in the setting of tuberous sclerosis, although they have also been described in the setting of von Hippel-Lindau syndrome (vHL)and neurofibromatosis type 1 (NF1) ^5,7. In these cases, they present earlier (usually identified by the age of 10 years), are larger, and are far more numerous. They are more likely to be fat-poor which accounts for their earlier presentation ^2,6,7.

Clinical presentation

Angiomyolipomas are often found incidentally when the kidneys are imaged for other reasons, or as part of screening in patients with tuberous sclerosis.

Symptomatic presentation is most frequently with spontaneous retroperitoneal ~~haemorrhage~~hemorrhage; the risk of bleeding is proportional to the size of the lesion (>4 cm diameter). Shock due to severe ~~haemorrhage~~hemorrhage from rupture is described as Wunderlich syndrome ^4,5,7.

Patients may present with numerous other symptoms and signs ², e.g. palpable mass, flank pain, urinary tract infections, ~~haematuria~~hematuria, renal failure, or hypertension ³.

Pathology

Angiomyolipomas are members of the perivascular epithelioid cells ~~tumour~~tumor group (PEComas) and are composed of variable amounts of three components; blood vessels (-angio), plump spindle cells (-myo) and adipose tissue (-lipo).

Almost all classic angiomyolipomas are benign but they do have the risk of rupture with bleeding or secondary damage/destruction of surrounding structures as they grow.

Variants

~~There is a~~ Two histological types have been described

typical (triphasic)
atypical (monophasic or epithelioid)

A special variant called an epithelioid angiomyolipoma, is composed of more plump, epithelial-looking cells, often with nuclear atypia, that have a described risk of malignant ~~behaviour~~behavior. This variant, unlike conventional AMLs, may mimic renal cell carcinoma ¹⁰. Metastases have also been described ⁹.

Radiographic features

The cornerstone of diagnosis on all modalities is the demonstration of macroscopic fat, however in the setting of ~~haemorrhage~~hemorrhage, or when lesions happen to contain little fat, it may be difficult to distinguish an angiomyolipoma from a renal cell carcinoma.

Ultrasound

tend to appear as hyperechoic lesions on ultrasound, located in the cortex and with posterior acoustic shadowing
in the setting of tuberous sclerosis, they may be so numerous that the entire kidney is affected, appearing echogenic with the loss of normal corticomedullary differentiation ⁷
contrast-enhanced ultrasound ¹²
- tend to enhance peripherally
- decreased central enhancement, compared with normal cortex

CT

Most lesions involve the cortex and demonstrate macroscopic fat (less than -20 HU). When small, volume averaging may make differentiation from a small cyst difficult.

It is important to ~~realise~~realize that ~5% of angiomyolipomas are fat-poor ¹⁵. This is especially the case in the setting of tuberous sclerosis, where up to a third do not demonstrate macroscopic fat on CT ⁶. Calcification is rare.

MRI

MRI is excellent at evaluating fat-containing lesions, and two main set of sequences are employed. Firstly, and traditionally if you will, fat saturated techniques demonstrate high signal intensity on non-fat-saturated sequences and loss of signal following fat saturation.

The second method is to use in-phase and out-of-phase imaging which generates I ndia ink artifact at the interface between fat and non-fat components. This can occur either at the interface between the angiomyolipoma and surrounding kidney or between fat and non-fat components of the mass ⁸. Chemical shift signal intensity loss, along with other features, may suggest a fat-poor AML ¹⁵.

It is essential to remember that rarely renal cell carcinomas may have macroscopic fat components and as such the presence of fat is strongly indicative of an angiomyolipoma, but not pathognomonic. Since macroscopic fat in renal cell carcinoma almost always occurs in the presence of ossification/calcification, absence of ossification/calcification on imaging is in ~~favour~~favor of AML.

DSA - angiography

Angiomyolipomas are hypervascular lesions demonstrating often characteristic features:

arterial phase: a sharply marginated hypervascular mass with a dense early arterial network, and tortuous vessels giving the "sunburst" appearance
venous phase: whorled "onion peel" appearance of peripheral vessels
micro- or macro-aneurysms ²
absent arteriovenous shunting

Treatment and prognosis

Angiomyolipomas found incidentally usually require no therapy (when small), although follow-up is recommended to assess for growth. Small solitary AMLs (<20 mm) probably do not require follow-up due to their slow growth ¹³.

Larger AMLs, or those that have been symptomatic, can be electively ~~embolised~~embolized and/or resected with a partial nephrectomy.

Lesions that present with retroperitoneal ~~haemorrhage~~hemorrhage often requires emergency ~~embolisation~~embolization as a life-saving measure.

mTOR inhibitors (e.g. everolimus) have been shown to significantly decrease AML size and may help to preserve renal function in tuberous sclerosis patients.

Differential diagnosis

When an AML has typical appearances there is essentially no differential. If atypical, especially when fat-poor, other lesions to consider include:

retroperitoneal liposarcoma invading the kidney:
- presence of a large vessel extending into the renal cortex suggestive of AML; liposarcoma is hypovascular
- renal parenchymal defect at the site of ~~tumour~~tumor contact ~~favours~~favors exophytic angiomyolipoma - claw sign
- calcifications suggest liposarcoma
adrenal myelolipoma
renal cell carcinoma (RCC)
- may contain fat: lipid necrosis or osseous metaplasia
oncocytoma: may contain fat
Wilms ~~tumour~~tumor: may contain fat
perirenal fat entrapment / renal junctional parenchymal defect ¹¹

-<p><strong>Renal angiomyolipomas (AML)</strong> are a type of <a href="/articles/who-histological-classification-of-benign-renal-neoplasms">benign renal neoplasm</a> encountered both sporadically and as part of a phakomatosis, most commonly <a href="/articles/tuberous-sclerosis">tuberous sclerosis</a>. They are considered one of a number of tumours with <a href="/articles/perivascular-epithelioid-cell-tumours-pecomas-1">perivascular epitheloid cellular </a><a href="/articles/perivascular-epithelioid-cell-tumours-pecomas-1">differentiation</a><a href="/articles/perivascular-epithelioid-cell-tumours-pecomas-1"> (PEComas)</a> and are composed of vascular, smooth muscle and fat elements. They can spontaneously haemorrhage, which may be fatal. AMLs usually have characteristic radiographic appearances. </p><h4>Epidemiology</h4><p>Angiomyolipomas are the most common benign solid renal lesion and also the most common <a href="/articles/fat-containing-renal-lesions">fat-containing lesion of the kidneys</a>. The majority of angiomyolipomas are sporadic (80%) and are typically identified in adults (mean age of presentation 43 years), with a strong female predilection (F:M of 4:1) <sup>7,9</sup>. </p><p>The remaining 20% are seen in association with <a href="/articles/phakomatoses">phakomatoses</a>, the vast majority in the setting of <a href="/articles/tuberous-sclerosis">tuberous sclerosis</a>, although they have also been described in the setting of <a href="/articles/von-hippel-lindau-disease-5">von Hippel-Lindau syndrome (vHL)</a><a href="/articles/von-hippel-lindau-syndrome-vhl-"> </a>and <a href="/articles/neurofibromatosis-type-1">neurofibromatosis type 1 (NF1)</a> <sup>5,7</sup>. In these cases, they present earlier (usually identified by the age of 10 years), are larger, and are far more numerous. They are more likely to be fat-poor which accounts for their earlier presentation <sup>2,6,7</sup>.</p><h4>Clinical presentation</h4><p>Angiomyolipomas are often found incidentally when the kidneys are imaged for other reasons, or as part of screening in patients with tuberous sclerosis.</p><p>Symptomatic presentation is most frequently with spontaneous <a href="/articles/retroperitoneal-haemorrhage">retroperitoneal haemorrhage</a>; the risk of bleeding is proportional to the size of the lesion (>4 cm diameter). Shock due to severe haemorrhage from rupture is described as <a href="/articles/wunderlich-syndrome">Wunderlich syndrome</a> <sup>4,5,7</sup>.</p><p>Patients may present with numerous other symptoms and signs <sup>2</sup>, e.g. palpable mass, flank pain, <a href="/articles/urinary-tract-infection">urinary tract infections</a>, <a href="/articles/haematuria-adult">haematuria</a>, renal failure, or <a href="/articles/hypertension">hypertension</a> <sup>3</sup>.</p><h4>Pathology</h4><p>Angiomyolipomas are members of the <a href="/articles/pecoma">perivascular epithelioid cells tumour group (PEComas)</a> and are composed of variable amounts of three components; blood vessels (-angio), plump spindle cells (<strong>-</strong>myo) and adipose tissue (<strong>-</strong>lipo).</p><p>Almost all classic angiomyolipomas are benign but they do have the risk of rupture with bleeding or secondary damage/destruction of surrounding structures as they grow. </p><h5>Variants</h5><p>There is a special variant called an <a href="/articles/epithelioid-angiomyolipoma">epithelioid angiomyolipoma</a>, composed of more plump, epithelial-looking cells, often with nuclear atypia, that have a described risk of malignant behaviour. This variant, unlike conventional AMLs, may mimic renal cell carcinoma <sup>10</sup>. Metastases have also been described <sup>9</sup>. </p><h4>Radiographic features</h4><p>The cornerstone of diagnosis on all modalities is the demonstration of macroscopic fat, however in the setting of haemorrhage, or when lesions happen to contain little fat, it may be difficult to distinguish an angiomyolipoma from a <a href="/articles/renal-cell-carcinoma-1">renal cell carcinoma</a>.</p><h5>Ultrasound</h5><ul>
+<p><strong>Renal angiomyolipomas (AML)</strong> are a type of <a href="/articles/who-histological-classification-of-benign-renal-neoplasms">benign renal neoplasm</a> encountered both sporadically and as part of a phakomatosis, most commonly <a href="/articles/tuberous-sclerosis">tuberous sclerosis</a>. They are considered one of a number of tumors with <a href="/articles/perivascular-epithelioid-cell-tumours-pecomas-1">perivascular epitheloid cellular </a><a href="/articles/perivascular-epithelioid-cell-tumours-pecomas-1">differentiation</a><a href="/articles/perivascular-epithelioid-cell-tumours-pecomas-1"> (PEComas)</a> and are composed of vascular, smooth muscle and fat elements. They can spontaneously hemorrhage, which may be fatal. AMLs usually have characteristic radiographic appearances. </p><h4>Epidemiology</h4><p>Angiomyolipomas are the most common benign solid renal lesion and also the most common <a href="/articles/fat-containing-renal-lesions">fat-containing lesion of the kidneys</a>. The majority of angiomyolipomas are sporadic (80%) and are typically identified in adults (mean age of presentation 43 years), with a strong female predilection (F:M of 4:1) <sup>7,9</sup>. </p><p>The remaining 20% are seen in association with <a href="/articles/phakomatoses">phakomatoses</a>, the vast majority in the setting of <a href="/articles/tuberous-sclerosis">tuberous sclerosis</a>, although they have also been described in the setting of <a href="/articles/von-hippel-lindau-disease-5">von Hippel-Lindau syndrome (vHL)</a><a href="/articles/von-hippel-lindau-syndrome-vhl-"> </a>and <a href="/articles/neurofibromatosis-type-1">neurofibromatosis type 1 (NF1)</a> <sup>5,7</sup>. In these cases, they present earlier (usually identified by the age of 10 years), are larger, and are far more numerous. They are more likely to be fat-poor which accounts for their earlier presentation <sup>2,6,7</sup>.</p><h4>Clinical presentation</h4><p>Angiomyolipomas are often found incidentally when the kidneys are imaged for other reasons, or as part of screening in patients with tuberous sclerosis.</p><p>Symptomatic presentation is most frequently with spontaneous <a href="/articles/retroperitoneal-haemorrhage">retroperitoneal hemorrhage</a>; the risk of bleeding is proportional to the size of the lesion (>4 cm diameter). Shock due to severe hemorrhage from rupture is described as <a href="/articles/wunderlich-syndrome">Wunderlich syndrome</a> <sup>4,5,7</sup>.</p><p>Patients may present with numerous other symptoms and signs <sup>2</sup>, e.g. palpable mass, flank pain, <a href="/articles/urinary-tract-infection">urinary tract infections</a>, <a href="/articles/haematuria-adult">hematuria</a>, renal failure, or <a href="/articles/hypertension">hypertension</a> <sup>3</sup>.</p><h4>Pathology</h4><p>Angiomyolipomas are members of the <a href="/articles/pecoma">perivascular epithelioid cells tumor group (PEComas)</a> and are composed of variable amounts of three components; blood vessels (-angio), plump spindle cells (<strong>-</strong>myo) and adipose tissue (<strong>-</strong>lipo).</p><p>Almost all classic angiomyolipomas are benign but they do have the risk of rupture with bleeding or secondary damage/destruction of surrounding structures as they grow. </p><h5>Variants</h5><p>Two histological types have been described </p><ul>
+<li>typical (triphasic)</li>
+<li>atypical (monophasic or epithelioid)</li>
+</ul><p>A special variant called an <a href="/articles/epithelioid-angiomyolipoma">epithelioid angiomyolipoma</a> is composed of more plump, epithelial-looking cells, often with nuclear atypia, that have a described risk of malignant behavior. This variant, unlike conventional AMLs, may mimic renal cell carcinoma <sup>10</sup>. Metastases have also been described <sup>9</sup>. </p><h4>Radiographic features</h4><p>The cornerstone of diagnosis on all modalities is the demonstration of macroscopic fat, however in the setting of hemorrhage, or when lesions happen to contain little fat, it may be difficult to distinguish an angiomyolipoma from a <a href="/articles/renal-cell-carcinoma-1">renal cell carcinoma</a>.</p><h5>Ultrasound</h5><ul>
-</ul><h5>CT</h5><p>Most lesions involve the cortex and demonstrate macroscopic fat (less than -20 HU). When small, volume averaging may make differentiation from a small cyst difficult.</p><p>It is important to realise that ~5% of angiomyolipomas are fat-poor <sup>15</sup>. This is especially the case in the setting of tuberous sclerosis, where up to a third do not demonstrate macroscopic fat on CT <sup>6</sup>. Calcification is rare.</p><h5>MRI</h5><p>MRI is excellent at evaluating fat-containing lesions, and two main set of sequences are employed. Firstly, and traditionally if you will, fat saturated techniques demonstrate high signal intensity on non-fat-saturated sequences and loss of signal following fat saturation. </p><p>The second method is to use in-phase and out-of-phase imaging which generates <a href="/articles/india-ink-artifact">I</a><a href="/articles/india-ink-artifact">ndia ink </a><a href="/articles/india-ink-artifact">artifact</a> at the interface between fat and non-fat components. This can occur either at the interface between the angiomyolipoma and surrounding kidney or between fat and non-fat components of the mass <sup>8</sup>. Chemical shift signal intensity loss, along with other features, may suggest a fat-poor AML <sup>15</sup>. </p><p>It is essential to remember that rarely <a href="/articles/renal-cell-carcinoma-1">renal cell carcinomas</a> may have macroscopic fat components and as such the presence of fat is strongly indicative of an angiomyolipoma, but not <a href="/articles/pathognomonic">pathognomonic</a>. Since macroscopic fat in renal cell carcinoma almost always occurs in the presence of ossification/calcification, absence of ossification/calcification on imaging is in favour of AML. </p><h5>DSA - angiography</h5><p>Angiomyolipomas are hypervascular lesions demonstrating often characteristic features:</p><ul>
+</ul><h5>CT</h5><p>Most lesions involve the cortex and demonstrate macroscopic fat (less than -20 HU). When small, volume averaging may make differentiation from a small cyst difficult.</p><p>It is important to realize that ~5% of angiomyolipomas are fat-poor <sup>15</sup>. This is especially the case in the setting of tuberous sclerosis, where up to a third do not demonstrate macroscopic fat on CT <sup>6</sup>. Calcification is rare.</p><h5>MRI</h5><p>MRI is excellent at evaluating fat-containing lesions, and two main set of sequences are employed. Firstly, and traditionally if you will, fat saturated techniques demonstrate high signal intensity on non-fat-saturated sequences and loss of signal following fat saturation. </p><p>The second method is to use in-phase and out-of-phase imaging which generates <a href="/articles/india-ink-artifact">I</a><a href="/articles/india-ink-artifact">ndia ink </a><a href="/articles/india-ink-artifact">artifact</a> at the interface between fat and non-fat components. This can occur either at the interface between the angiomyolipoma and surrounding kidney or between fat and non-fat components of the mass <sup>8</sup>. Chemical shift signal intensity loss, along with other features, may suggest a fat-poor AML <sup>15</sup>. </p><p>It is essential to remember that rarely <a href="/articles/renal-cell-carcinoma-1">renal cell carcinomas</a> may have macroscopic fat components and as such the presence of fat is strongly indicative of an angiomyolipoma, but not <a href="/articles/pathognomonic">pathognomonic</a>. Since macroscopic fat in renal cell carcinoma almost always occurs in the presence of ossification/calcification, absence of ossification/calcification on imaging is in favor of AML. </p><h5>DSA - angiography</h5><p>Angiomyolipomas are hypervascular lesions demonstrating often characteristic features:</p><ul>
-</ul><h4>Treatment and prognosis</h4><p>Angiomyolipomas found incidentally usually require no therapy (when small), although follow-up is recommended to assess for growth. Small solitary AMLs (<20 mm) probably do not require follow-up due to their slow growth <sup>13</sup>. </p><p>Larger AMLs, or those that have been symptomatic, can be electively embolised and/or resected with a partial nephrectomy.</p><p>Lesions that present with retroperitoneal haemorrhage often requires emergency embolisation as a life-saving measure.</p><p>mTOR inhibitors (e.g. everolimus) have been shown to significantly decrease AML size and may help to preserve renal function in tuberous sclerosis patients.</p><h4>Differential diagnosis</h4><p>When an AML has typical appearances there is essentially no differential. If atypical, especially when fat-poor, other lesions to consider include:</p><ul>
+</ul><h4>Treatment and prognosis</h4><p>Angiomyolipomas found incidentally usually require no therapy (when small), although follow-up is recommended to assess for growth. Small solitary AMLs (<20 mm) probably do not require follow-up due to their slow growth <sup>13</sup>. </p><p>Larger AMLs, or those that have been symptomatic, can be electively embolized and/or resected with a partial nephrectomy.</p><p>Lesions that present with retroperitoneal hemorrhage often requires emergency embolization as a life-saving measure.</p><p>mTOR inhibitors (e.g. everolimus) have been shown to significantly decrease AML size and may help to preserve renal function in tuberous sclerosis patients.</p><h4>Differential diagnosis</h4><p>When an AML has typical appearances there is essentially no differential. If atypical, especially when fat-poor, other lesions to consider include:</p><ul>
~~-<li>renal parenchymal defect at the site of tumour contact favours exophytic angiomyolipoma - <a href="/articles/claw-sign-mass">claw sign</a>~~
+<li>renal parenchymal defect at the site of tumor contact favors exophytic angiomyolipoma - <a href="/articles/claw-sign-mass">claw sign</a>
~~-<a href="/cases/wilms-tumour">Wilms tumour</a>: may contain fat</li>~~
+<a href="/cases/wilms-tumour">Wilms tumor</a>: may contain fat</li>

References changed:

16. Vos N & Oyen R. Renal Angiomyolipoma: The Good, the Bad, and the Ugly. J Belg Soc Radiol. 2018;102(1):41. <a href="https://doi.org/10.5334/jbsr.1536">doi:10.5334/jbsr.1536</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/30039053">Pubmed</a>
17. Buj Pradilla M, Martí Ballesté T, Torra R, Villacampa Aubá F. Recommendations for Imaging-Based Diagnosis and Management of Renal Angiomyolipoma Associated with Tuberous Sclerosis Complex. Clin Kidney J. 2017;10(6):728-37. <a href="https://doi.org/10.1093/ckj/sfx094">doi:10.1093/ckj/sfx094</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/29225800">Pubmed</a>

Images Changes:

Image 4 CT (C+ portal venous phase) ( update )

Caption was changed:

Case 2: with complicating ~~haemorrhage~~hemorrhage

Image 10 DSA (angiography) (Renal artery) ( update )

Caption was changed:

Case 8: showing feeder vessel prior to ~~embolisation~~embolization

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16","thumbnail":"https://prod-images-static.radiopaedia.org/images/41714444/9c5ededa11387f4fd676db9e4d4f81476b40dff5e8fea426178775560a9fd510_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"probable"},{"imageId":41798126,"studyId":70710,"caseSlug":"tuberous-sclerosis-multiple-angiomyolipomas-1","caption":"Case 17: with tuberous sclerosis","thumbnail":"https://prod-images-static.radiopaedia.org/images/41798126/976c7d0f2e65398b10be9db1012cba_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":31817752,"studyId":61038,"caseSlug":"renal-angiomyolipoma-with-acute-haemorrhage","caption":"Case 18: with acute haemorrhage","thumbnail":"https://prod-images-static.radiopaedia.org/images/31817752/78c790181592d82a3f55c1ee674e1a_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":53716273,"studyId":97764,"caseSlug":"hemorrhagic-renal-angiomyolipoma","caption":"Case 19: haemorrhagic renal angiomyolipoma","thumbnail":"https://prod-images-static.radiopaedia.org/images/53716273/SAG105_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":53916236,"studyId":99671,"caseSlug":"renal-angiomyolipoma-32","caption":"Case 20","thumbnail":"https://prod-images-static.radiopaedia.org/images/53916236/110149_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":54165118,"studyId":101394,"caseSlug":"renal-angiomyolipoma-33","caption":"Case 21","thumbnail":"https://prod-images-static.radiopaedia.org/images/54165118/110071_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":53873480,"studyId":99434,"caseSlug":"renal-angiomyolipoma-30","caption":"Case 22","thumbnail":"https://prod-images-static.radiopaedia.org/images/53873480/110149_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":466125,"studyId":10440,"caseSlug":"renal-angiomyolipoma-34","caption":"Case 23","thumbnail":"https://prod-images-static.radiopaedia.org/images/466125/abf0cf174c13e101c24eb6422c4924_big_gallery.jpg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":54215320,"studyId":101702,"caseSlug":"renal-angiomyolipoma-35","caption":"Case 24","thumbnail":"https://prod-images-static.radiopaedia.org/images/54215320/110145_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":54460611,"studyId":103395,"caseSlug":"renal-angiomyolipoma-36","caption":"Case 25","thumbnail":"https://prod-images-static.radiopaedia.org/images/54460611/220157_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":54985922,"studyId":106242,"caseSlug":"renal-angiomyolipoma-38","caption":"Case 26","thumbnail":"https://prod-images-static.radiopaedia.org/images/54985922/110071_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":55060804,"studyId":106771,"caseSlug":"renal-angiomyolipoma-39","caption":"Case 27","thumbnail":"https://prod-images-static.radiopaedia.org/images/55060804/330321_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":55483844,"studyId":109058,"caseSlug":"renal-angiomyolipoma-41","caption":"Case 28","thumbnail":"https://prod-images-static.radiopaedia.org/images/55483844/110177_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":55622001,"studyId":109745,"caseSlug":"renal-angiomyolipoma-42","caption":"Case 29","thumbnail":"https://prod-images-static.radiopaedia.org/images/55622001/330061_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":55992397,"studyId":111665,"caseSlug":"renal-angiomyolipoma-44","caption":"Case 30","thumbnail":"https://prod-images-static.radiopaedia.org/images/55992397/10079_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":56168188,"studyId":112590,"caseSlug":"cystic-renal-angiomyolipoma-ceus","caption":"Case 30: cystic (CEUS)","thumbnail":"https://prod-images-static.radiopaedia.org/images/56168188/IMAGE_001-021_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":57039808,"studyId":116834,"caseSlug":"renal-angiomyolipoma-45","caption":"Case 31","thumbnail":"https://prod-images-static.radiopaedia.org/images/57039808/37._big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":58895658,"studyId":122892,"caseSlug":"renal-angiomyolipoma-46","caption":"Case 32","thumbnail":"https://prod-images-static.radiopaedia.org/images/58895658/4fa640f3395202170408bb5679cdd1d85d0e85c3806a240d67d589bc86ec351f_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":59369031,"studyId":125297,"caseSlug":"large-renal-angiomyolipoma-2","caption":"Case 33","thumbnail":"https://prod-images-static.radiopaedia.org/images/59369031/1064e85cf8a39a3a4aa7e44e633e5bbd5aed4e0231e4ba0e0632742db25b7e47_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":61127080,"studyId":132102,"caseSlug":"exophytic-renal-angiomyolipoma-3","caption":"Case 34: exophytic renal angiomyolipoma","thumbnail":"https://prod-images-static.radiopaedia.org/images/61127080/3604ffecead1cbcf4c3e082efb7e93c8fe3ffe9c71c244482932609082d95106_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":62681710,"studyId":138137,"caseSlug":"lymphangioleiomyomatosis-and-renal-angiomyolipoma-in-tuberous-sclerosis-complex","caption":"Case 35","thumbnail":"https://prod-images-static.radiopaedia.org/images/62681710/28f1ffb6349bf2ecb50813ffadbfaae4f2863a1f941c0266a49ff97af3977a78_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":63345825,"studyId":140887,"caseSlug":"ruptured-renal-angiomyolipoma-causing-pleuritic-chest-pain-diagnosed-on-ctpa","caption":"Case 36: diagnosed on CTPA","thumbnail":"https://prod-images-static.radiopaedia.org/images/63345825/6315bcc02a2c950ab620f0e00b9f1b4c54a279baab774bbb420a5966e0db1397_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":63594857,"studyId":142072,"caseSlug":"renal-angiomyolipoma-47","caption":"Case 37","thumbnail":"https://prod-images-static.radiopaedia.org/images/63594857/d362975f20d31bcf9baf9ccb294a66b2bf8ca8e6c0511664db3fa51e159531f3_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":64045711,"studyId":143964,"caseSlug":"wunderlich-syndrome-with-pseudoaneurysm-due-to-angiomyolipoma-rupture","caption":"Case 38: with Wunderlich syndrome and pseudoaneurysm","thumbnail":"https://prod-images-static.radiopaedia.org/images/64045711/e3d3fcb4e1e1b1efe3a9b528e64644d9a50914eae1f65c823c29f765a1472f22_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":65582975,"studyId":149148,"caseSlug":"giant-renal-angiomyolipomas-in-a-patient-with-tuberous-sclerosis","caption":"Case 39: giant angiomyolipomas","thumbnail":"https://prod-images-static.radiopaedia.org/images/65582975/454ad72be83320a6ad0898cce283461af5c732b3c14c48ac71031e99b8ed8e91_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"}],"ddx_inclusions":[{"imageId":2962476,"studyId":21827,"caseSlug":"retroperitoneal-liposarcoma-3","caption":"Retroperitoneal liposarcoma","thumbnail":"https://prod-images-static.radiopaedia.org/images/2962476/cfb3a58f3e7fe52e80ce0aaae6eac2_big_gallery.jpg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":28044,"studyId":7960,"caseSlug":"adrenal-myelolipoma","caption":"Adrenal myelolipoma","thumbnail":"https://prod-images-static.radiopaedia.org/images/28044/c2c188939bacad0be6c5281a840228_big_gallery.jpg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"}],"lang":"gb"}