Small (< or = 4 cm) cortical renal tumors: characterization with multidetector CT.
BACKGROUND
To determine if the pathology of small (< or = 4 cm) solid renal tumors can be predicted from findings on multidetector CT.


METHODS
This retrospective study included 46 patients (median age, 60 years; range, 32-91 years; 27 males, 19 females) with 47 tumors who underwent triphasic renal CT with pathology correlation. Two radiologists reviewed CT studies blinded to pathology results and recorded the morphologic and enhancement features of the tumors.


RESULTS
The 47 tumors (median diameter, 2.5 cm; range, 0.6-4.0 cm) included: 26 (55%) clear cell renal cell carcinomas; 9 (19%) oncocytomas; 7 (15%) papillary renal cell carcinomas; 2 (4%) chromophobe renal cell carcinomas; 2 (4%) inflammatory pseudotumors; and 1 (2%) angiomyolipoma with minimal fat. Amongst the three commonest tumors, heterogeneity was seen in 23/26 (88%) clear cell renal cell carcinomas, 6/9 (67%) oncocytomas, and 2/7 (29%) papillary renal cell cancer. Median (minimum-maximum) absolute nephrographic phase enhancement (nephrographic minus unenhanced phase) was: clear cell renal cell carcinomas 65 HU (34-120), oncocytomas 80 HU (51-111), and papillary renal cell carcinomas 16 HU (7-32).


CONCLUSIONS
Absolute nephrographic phase enhancement of < or = 32 HU distinguished papillary renal cell carcinomas from clear cell renal cell carcinomas and oncocytomas.
Alshumrani
Ghazi
G
Department of Medical Imaging, University of Toronto, Toronto, Canada.
O'Malley
Martin
M
Ghai
Sangeet
S
Metser
Ur
U
Kachura
John
J
Finelli
Antonio
A
Mattar
Kamal
K
Panzarella
Tony
T
D018249:Adenoma, Oxyphilic / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018207:Angiomyolipoma / Q000000981:diagnostic imaging / Q000473:pathology; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006104:Granuloma, Plasma Cell / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007672:Kidney Cortex / Q000000981:diagnostic imaging; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed