Qualitative and quantitative MDCT features for differentiating clear cell renal cell carcinoma from other solid renal cortical masses.

Abstract

OBJECTIVE:

The purpose of this study was to differentiate clear cell renal cell carcinoma (RCC) from other solid renal masses on four-phase MDCT.

MATERIALS AND METHODS:

Our study cohort included all pathologically proven solid renal masses that underwent pretreatment four-phase MDCT at our institution from 2001 to 2012. Both retrospective qualitative analysis (blinded dual-radiologist evaluation of morphologic features: enhancement pattern, lesion contour, neovascularity, and calcification) and quantitative analysis (mean absolute and relative attenuation and changes in attenuation across phases) were performed. ANOVA with post-hoc analysis, Pearson chi-square tests, and ROC analysis were used.

RESULTS:

One hundred fifty-six consecutive patients (99 men, 57 women) with a mean age of 62.7 years (range, 26-91 years) had 165 solid renal masses (median size, 3.0 cm): 86 clear cell RCCs, 36 papillary RCCs, 10 chromophobe RCCs, 23 oncocytomas, and 10 lipid-poor angiomyolipomas. Kappa for interradiologist agreement regarding morphologic features was 0.33-0.76. There were significant associations between histologic subtype and enhancement pattern (p < 0.001), lesion contour (p < 0.014), and neovascularity (p < 0.001). Clear cell RCC had the highest mean relative corticomedullary attenuation (p < 0.02). Clear cell RCC had greater deenhancement than oncocytoma (p < 0.001); deenhancement less than 50 HU or relative corticomedullary attenuation greater than 0% differentiated clear cell RCC from oncocytoma with a positive predictive value of 90%. Lipid-poor angiomyolipoma had the highest mean absolute unenhanced attenuation (p < 0.01); absolute unenhanced attenuation greater than 45 HU and relative corticomedullary attenuation less than 10% differentiated lipid-poor angiomyolipoma from clear cell RCC with a negative predictive value of 97%.

CONCLUSION:

Four-phase MDCT renal attenuation profiles enable differentiation of clear cell RCC from other solid renal cortical masses, most notably papillary RCC and lipid-poor angiomyolipoma.

• Authors: Stephanie A Lee-Felker, Ely R Felker, Nelly Tan, Daniel J A Margolis, Jonathan R Young, James Sayre, Steven S Raman
• Journal: AJR. American journal of roentgenology (AJR Am J Roentgenol) Vol. 203 Issue 5 Pg. W516-24 (Nov 2014) ISSN: 1546-3141 [Electronic] United States
• PMID: 25341166 (Publication Type: Journal Article)

Topics

• Adult
• Aged
• Aged, 80 and over
• Algorithms
• Carcinoma, Renal Cell (diagnostic imaging)
• Cohort Studies
• Diagnosis, Differential
• Female
• Humans
• Kidney Neoplasms (diagnostic imaging)
• Male
• Middle Aged
• Multidetector Computed Tomography (methods)
• Observer Variation
• Radiographic Image Enhancement (methods)
• Radiographic Image Interpretation, Computer-Assisted (methods)
• Reproducibility of Results
• Sensitivity and Specificity