You have accessJournal of UrologyImaging/Radiology: Uroradiology1 Apr 20112300 DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING IN DIFFERENTIATION OF ANGIOMYOLIPOMA WITH MINIMAL FAT FROM CLEAR CELL RENAL CELL CARCINOMA Hajime Tanaka, Soichiro Yoshida, Yasuhisa Fujii, Chikako Ishii, Fumitaka Koga, Kazutaka Saito, Hitoshi Masuda, Satoru Kawakami, and Kazunori Kihara Hajime TanakaHajime Tanaka Tokyo, Japan More articles by this author , Soichiro YoshidaSoichiro Yoshida Tokyo, Japan More articles by this author , Yasuhisa FujiiYasuhisa Fujii Tokyo, Japan More articles by this author , Chikako IshiiChikako Ishii Tokyo, Japan More articles by this author , Fumitaka KogaFumitaka Koga Tokyo, Japan More articles by this author , Kazutaka SaitoKazutaka Saito Tokyo, Japan More articles by this author , Hitoshi MasudaHitoshi Masuda Tokyo, Japan More articles by this author , Satoru KawakamiSatoru Kawakami Tokyo, Japan More articles by this author , and Kazunori KiharaKazunori Kihara Tokyo, Japan More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2546AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The widespread use of modern imaging has resulted in the increased detection of small, asymptomatic renal tumors. Recent studies have revealed that approximately 20% of these small renal masses are pathologically benign at nephrectomy despite expert preoperative radiologic evaluation. The high level of noncancerous lesions is, to some extent, due to that no imaging feature can accurately distinguish oncocytoma and angiomyolipoma (AML) with minimal fat from renal cell carcinoma. We evaluated the value of diffusion-weighted magnetic resonance imaging (DW-MRI) in differentiating between AML with minimal fat and clear cell renal cell carcinoma (CCRCC). METHODS Between April 2006 and March 2009, 41 renal tumors without visible macroscopic fat on unenhanced CT images were evaluated by MRI, including DW-MRI, and were pathologically diagnosed as CCRCC (n = 36) or AML with minimal fat (n = 5). To evaluate the heterogeneity of diffusion in each tumor, we analyzed the signals of the tumors on DW-MRI subjectively and the apparent diffusion coefficient (ADC) values and histograms objectively. RESULTS Thirty-three (92%) of the 36 CCRCCs exhibited a heterogeneous signal on DW-MRI and several peaks in the ADC value histogram whereas 4 (80%) of the 5 AMLs with minimal fat exhibited a homogeneous signal on DW-MRI and a single prominent peak in the histogram. Although there was no significant difference in the minimum ADC value between them, the standard deviations (SDs) of the ADC value of AMLs were significantly smaller than those of CCRCCs (P = 0.0015). These differences were also found in the size-matched cohort. CONCLUSIONS DW-MRI may be a useful and noninvasive addition to the preoperative differentiation of CCRCC and AML with minimal fat. Most AMLs with minimal fat exhibited homogeneity of diffusion on DW-MRI whereas many CCRCCs exhibited heterogeneity. These findings were confirmed objectively by the significant difference in the SDs of ADC values and the patterns of the ADC value histogram. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e922 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hajime Tanaka Tokyo, Japan More articles by this author Soichiro Yoshida Tokyo, Japan More articles by this author Yasuhisa Fujii Tokyo, Japan More articles by this author Chikako Ishii Tokyo, Japan More articles by this author Fumitaka Koga Tokyo, Japan More articles by this author Kazutaka Saito Tokyo, Japan More articles by this author Hitoshi Masuda Tokyo, Japan More articles by this author Satoru Kawakami Tokyo, Japan More articles by this author Kazunori Kihara Tokyo, Japan More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...