Learning objectives
To highlight the imaging characteristics of angiomyolipomas(AMLs) as isolated form or part of the tuberous sclerosis complex(TSC).
To list the imaging diagnostic clues for distinguishing AMLs from other renal tumors.
To present the role of interventional radiologist for the treatment of hemorrhagic complications.
Background
Definition:AML is a solid benign tumor composed of varying proportions of adipose tissue,
smooth muscle and abnormal blood vessels.
Epidemiology:AMLs are more frequent in woman than in man(4:1) with a peak of incidence between the fourth-sixth decades of life[1].
Clinic:Most commonly AMLs are asymptomatic,
but lesions>4cm can present with retroperitoneal hemorrhage due to tumor rupture and severe symptoms as:
anemia
hematuria
flank pain
palpable mass
renal failure
Histology:Although once considered a hamartoma,
AML is now considered among the family of perivascular epithelioid cell tumors(PEComa)[2] and...
Findings and procedure details
A.IMAGING TECHNIQUE
1.USusing curvilinear abdominal probe,
frequency 2-7MHz and color Doppler technique.
2.The CT protocol:
non-enhanced CT(NECT)-5mm slice thickness;
triphasic contrast-enhanced CT(CECT) with MPR:
- corticomedullary phase(25-40 seconds delay),
- nephrographic(80-90 seconds delay),
- excretory phase(240-300 seconds delay)
1,5ml/kg body weight of iodinated CM(370 mg iodine/ml)
3.MRIperformed with a 1.5-T system during an end-expiratory breath hold using:
-axial T1-w in/opposed-phase;
-axial/coronal T2-w with/without fat suppression(FS);
-3D T1-w with FS,
before and after administration of an intravenous
CM (gadolinium chelate - 0.1 mmol/kg)–dynamic triphase protocol.
B.IMAGING...
Conclusion
Knowing the current classification types of AMLs,
imaging appearance and proper imaging technique helps in both diagnosis and treatment.
Although the presence of fat attenuation is well-established diagnostic imaging,
sometimes AML exhibits atypical findings with fat-poor content overlapping with the appearance of other renal tumors.
Therefore,
it is imperative to meticulously evaluate all solid renal masses for the presence of fat to avoid recommending surgical excision of an angiomyolipoma.
Personal information
Dr.
MiaMadalina Ifrosa
mail:
[email protected]
Prof.Dr.Ioana G.Lupescu
mail:
[email protected]
Radiology,
Medical Imaging and Interventional Radiology Department
Fundeni Clinical Institute.
UMPh Carol Davila,
Bucharest,
Romania
References
[1]Lane BR,
Aydin H et al.
Clinical correlates of renal angiomyolipoma subtypes in 209 patients: classic,
fat poor,
tuberous sclerosis associated and epithelioid.
J Uro,2008;
[2]Eble JN,
Sauter G et al.
IA World Health Organization classification of tumors: pathology and genetics.
Tumors of the urinary system and male genital organs.
Lyon: IARC Press,2004;
[3]Jinzaki M,
Silverman SG et al.
Diagnosis of renal angiomyolipomas: classic,
fat-poor,
and epithelioid types.
Semin Ultrasound CT MR,2017;
[4]Song S,
Park BK et al.
New radiologic classification of renal angiomyolipomas.
Eur...
