Renal cell carcinoma: preoperative assessment for enucleative surgery with angiography, CT, and MRI.
OBJECTIVE
Our purpose was to assess various imaging methods in detecting a pseudocapsule of renal cell carcinoma (RCC), which is critical for successful tumor enucleation.


METHODS
In 42 patients with histopathologically proven RCC, images obtained at angiography (n = 42), CT (n = 30), and MRI (n = 19) were investigated retrospectively. All patients underwent treatment (enucleation: n = 15; nephrectomy: n = 27). The imaging criteria for the presence of a pseudocapsule were as follows: a surrounding radiolucent rim on angiography, a low or high density rim on CT, and a low intensity rim on MRI. All images were retrospectively reviewed by three radiologists without knowledge of the clinical and histological findings.


RESULTS
Thirty-three of 42 RCCs showed a pseudocapsule on the surgical specimen. A pseudocapsule was detected in 67% of tumors (22/33) on angiography, 26% (6/23) on CT, 27% (4/15) on T1-weighted MRI, 93% (14/15) on T2-weighted MRI, 67% (8/12) on dynamic enhanced T1-weighted MRI, and 15% (2/13) on delayed enhanced T1-weighted MRI.


CONCLUSIONS
T2-weighted MR images are superior for visualizing a pseudocapsule of RCC and for providing reliable selection criteria for tumor enucleation.
Takahashi
S
S
Department of Radiology, Osaka University Medical School, Japan.
Ueda
J
J
Furukawa
T
T
Higashino
K
K
Tsujihata
M
M
Itatani
H
H
Narumi
Y
Y
Nakamura
H
H
D000328:Adult; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy; D011300:Preoperative Care; D012077:Renal Artery / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data