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Current Urology Reports
Published in: Current Urology Reports 3/2015

01-03-2015 | New Imaging Techniques (A Rastinehad and S Rais-Bahrami, Section Editors)

Renal Angiomyolipoma: Preoperative Identification of Atypical Fat-Poor AML

Authors: Crystal Farrell, Sabrina L. Noyes, Mouafak Tourojman, Brian R. Lane

Published in: Current Urology Reports | Issue 3/2015

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Abstract

The preoperative distinction between benign and malignant renal masses is a well-known radiographic diagnostic challenge. With angiomyolipoma (AML) and renal cell carcinoma (RCC) representing the most common benign and malignant renal parenchymal lesions, respectively, differentiating these two entities is especially important due to their vastly different treatments and prognoses. Renal AML is typically composed of smooth muscle cells, dysmorphic blood vessels, and varying amounts of adipose tissue. In most cases, “typical” AML can be diagnosed by identifying macroscopic fat with ultrasound, computed tomography, or magnetic resonance imaging. However, approximately 4–5 % of AML tumors have fat that is grossly undetectable by conventional techniques, precluding a straightforward diagnosis. The overlapping radiographic features between “atypical” or “fat-poor” AML and RCC, especially in smaller (<3–4 cm) lesions, lead many patients with benign AML to undergo unnecessary surgery for suspected RCC when the diagnosis is not established beforehand. This review presents the most recent studies and developments in preoperative evaluation of fat-poor AML.
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Metadata
Title
Renal Angiomyolipoma: Preoperative Identification of Atypical Fat-Poor AML
Authors
Crystal Farrell
Sabrina L. Noyes
Mouafak Tourojman
Brian R. Lane
Publication date
01-03-2015
Publisher
Springer US
Published in
Current Urology Reports / Issue 3/2015
Print ISSN: 1527-2737
Electronic ISSN: 1534-6285
DOI
https://doi.org/10.1007/s11934-015-0484-z

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