This document discusses angiomyolipomas (AML), a type of benign renal tumor composed of blood vessels, smooth muscle, and fat cells. It describes the typical presentation of isolated and tuberous sclerosis-associated AML, including that isolated AML most often present as solitary lesions in the right kidney in women, while AML associated with tuberous sclerosis are typically bilateral and occur equally in men and women. Imaging findings are also summarized, noting the characteristic fat content visible on CT and MRI that appears echogenic on ultrasound and enhances heterogeneously after contrast. Angiography further demonstrates the hypervascular and tortuous nature of AML vasculature.

1. Genito-
Urinary
Tumors
Episode 2

2. Genito-Urinary Tumors
• Renal tumors.
• Tumors of the ureter.
• Bladder tumors.
• Prostate tumors.
• Testicular tumors.

3. Angiomyolipoma
• Benign.
• Vessel + Smooth Muscle + Fat.
• 2 Types:
Pathology:
1. Isolated.
2. Associated with
syndromes (as
Tuberous
Sclerosis)

4. Angiomyolipoma
• 80% of AMLs.
• Solitary.
• 20-70 years of age.
• Female/Male = 4/1.
• 80% in the Right Kidney !!
Isolated AML

5. Angiomyolipoma
• 20% of AMLs.
• Bilateral and multiple.
• 1-20 years of age.
• Female/Male = Near equal.
• AML occurs in 80% patients with tuberous
sclerosis.
AML with Tuberous Sclerosis

6. Angiomyolipoma
Clinical:
• 60% asymptomatic.
• 40% are symptomatic; these can cause a
palpable abdominal mass, hematuria, or flank
pain.
• The solitary sporadic tumors may cause acute
abdomen and shock as a result of
spontaneous hemorrhage in the tumor.

7. Angiomyolipoma
I. Plain X-Ray:
• Radiolucent mass.

8. Angiomyolipoma
II. IVU:
• Single or multiple
lucent defects.
• Distortion of the
calyces.

9. Angiomyolipoma
III.US:
• Round or oval cortical
masses.
• Intensely echogenic.
• Well circumscribed.

10. Angiomyolipoma
III.US:
• Round or oval cortical
masses.
• Intensely echogenic.
• Well circumscribed.

11. Angiomyolipoma
IV.CT:
NECT:
• Well circumscribed round or
oval cortical masses.
• Fat.

12. Angiomyolipoma
IV.CT:
CECT:
• Early/CTA → +/- Aneurysm.
• Fat.

13. Angiomyolipoma
IV.CT:
CECT:
• Nephrographic Phase → +/-Heterogeneous
enhancement.
• Fat.

14. Angiomyolipoma
IV.CT:

15. Angiomyolipoma
IV.CT:

16. Angiomyolipoma
IV.CT:

17. Angiomyolipoma
V. MRI:
Variable areas of high signal intensity within
the tumor on both T1-weighted and T2-
weighted images

18. Angiomyolipoma
V. MRI:
T1W:
Pre → High signal intensity is present
because of the fat content.
Post → Heterogeneous enhancement.

19. Angiomyolipoma
V. MRI:

20. Angiomyolipoma
V. MRI:
T2W:
Isointense relative to that of perinephric fat.

21. Angiomyolipoma
V. MRI:
Fat-Suppression:
Signal intensity dropout of fat .

22. Angiomyolipoma
V. Angiography:
• 95% of AMLs are hypervascular.
• Enlarged interlobar and interlobular arteries.
• Intratumoral arteries are tortuous, irregular, and
aneurysmal.
• Venous pooling exists, with a sunburst, whorled, and
onion-peel appearance.
• No arteriovenous (AV) shunting is present.

23. Angiomyolipoma
VI.Angiography:

24. Angiomyolipoma
VI.Angiography:

25. Angiomyolipoma
VI.Angiography:

26. Angiomyolipoma
VI.Angiography:
• The presence of multisacculated pseudoaneurysms, the
absence of AV shunting, a sunburst appearance of the
capillary nephrogram, and an onion-skin appearance of
the peripheral vessels in the venous phase suggest AML.