title: Renal cell carcinoma: value of multiphase MDCT with multiplanar reformations in the detection of pseudocapsule.
abstract: OBJECTIVE
  The purpose of this study was to assess the diagnostic performance of four-phase (unenhanced, arterial, portal, and nephrographic-excretory) MDCT with multiplanar reformations in the detection of pseudocapsule of renal cell carcinoma (RCC).
  
  
  METHODS
  In a retrospective study of 29 histologically proven RCCs in 29 patients (17 men, 12 women; mean age, 59 years), examinations were performed with a 16-MDCT scanner. The protocol included unenhanced and three-phase (arterial, portal, and nephrographic-excretory) contrast-enhanced CT. The data were analyzed by two reviewers blinded to the histopathologic results. Any discrepancy was resolved by consensus. The presence of a regular, high- or low-attenuation halo surrounding a renal neoplasm was considered to represent renal pseudocapsule. The accuracy of MDCT in the detection of pseudocapsule with the histopathologic results as the standard of reference was evaluated. Unenhanced transverse images and multiplanar reformations in the transverse, coronal, and sagittal planes of each contrast-enhanced phase were separately analyzed. The chi-square two-way test was used to compare each CT phase and multiplanar reformation with histologic results.
  
  
  RESULTS
  The mean diameter of RCCs on CT scans was 5.6 cm (range, 2.8-15 cm), in accordance with the pathologic result. MDCT enabled detection of renal pseudocapsule in 20 of 29 RCCs with 83% sensitivity, 80% specificity, 95% positive predictive value, 50% negative predictive value, and 83% overall accuracy. Imaging in the portal and nephrographic phases with coronal and sagittal reformations proved more accurate in the detection of pseudocapsule (p < 0.05).
  
  
  CONCLUSIONS
  Multiphase MDCT with multiplanar reformations had satisfactory results in the detection of renal pseudocapsule in RCC.
authors: Department of Clinical Radiology, University Hospital of Ioannina, Leoforos S. Niarchou, 45500, Pl Pargis, 2, 45332, Ioannina, Greece. a_tsili@yahoo.gr
authors: Athina C
authors: AC
authors: Tsili
authors: Maria I
authors: MI
authors: Argyropoulou
authors: Anna
authors: A
authors: Gousia
authors: John
authors: J
authors: Kalef-Ezra
authors: Nikolaos
authors: N
authors: Sofikitis
authors: Vasiliki
authors: V
authors: Malamou-Mitsi
authors: Konstantinos
authors: K
authors: Tsampoulas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging* / Q000473:pathology; D016009:Chi-Square Distribution; D003287:Contrast Media; D005260:Female; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C093233:iobitridol; D007472:Iohexol