Contrast-enhanced CT Findings And The Comparative Study With Its Pathological Grade For Diagnosising Clear Cell Renal Cell Carcinoma

Part one.Tumor CT measurements in clear cell renal cell carcinoma influence of different ROI methods on tumor attenuationObjective: To assess the influence of different region of interest(ROI)methods on tumor attenuation and the measurement consistency in patients with clear cell renal cell carcinoma.Materials and Methods: Fifty cases confirmed by pathology clear cell renal cell carcinoma patients were collected.The CT attenuation were measured according to three ROI protocols:freehand outline ROI,single-slice or small solid samples by the same researcher for two times.The CT attenuation collected by one researcher for two times using each setting method were the final CT vaules of every phase measured by the ROI setting method.The three protocols were compared for differences in CT attenuation and the interclass correlation coefficient(ICC)were also calculated.Intra-observer and inter-observer variability using paired sample t test and Bland-Altman plot.Results: The three methods of ROI set had significant differences from each other.The CT attenuation for small solid samples were significantly higher than the other two ROIs.The CT attenuation obtained by ROIs for freehand outline ROI,single-slice and small solid sample were good consistent(ICC>0.7).ICC for the freehand outline ROI was excellent(ICC>0.9).And the results of Bland-Altman plot show that methods of freehand outline ROI is the most reproducible.Conclusions:There were statistically significant differences among the three different ROI methods.The tumor analysis by outlined ROI protocol can provide more reproducible and stable results.Part two.Clear cell renal cell carcinoma : Preliminary study on correlations between Multidetector Contrast-Enhanced CT Findings and Fuhrman gradeObjective To evaluate the correlation between multidetector computed tomography CT image findings and the Fuhrman grade of clear cell renal cell carcinoma(cc RCC).Methods CT data of 108 renal cell clear cell carcinoma patients confirmed by pathology and Fuhrman grading were collected and the CT attenuation of tumor parenchyma,ipsilateral renal cortex and aorta were recorded and measured,absolute and relative enhancement of tumor parenchyma were calculated.According to the Fuhrman pathological classification,the data were divided into low grade(Fuhrman Ⅰ-Ⅱ)and high grade(FuhrmanⅢ-Ⅳ)and were compared by T test.And then CT imging variables were analyzed by Spearman Correlation and ROC curves and AUCs.Results A total of 81 low-grade and 27 high-grade CCRRCs were assessed.Low-grade tumors were differed from high-grade tumors with lower attenuation on unenhanced CT scan(P<0.05),absolute enhancement values in three phases were higher(P<0.05),relative enhancement values were also higher in arterial and venous phases(P<0.05).And in the delay phase relative enhancement values were also higher,but there was no significant difference between them.The absolute enhancement in nephrographic(r=-0.304,P<0.05)and delay phase(r=-0.310,P<0.05)and A1(r=-0.311,P< 0.05)were negatively correlated to the Fuhrman grade.A1(AUC=0.707)C1(AUC=0.705)and corticomedullary phase absolute enhancement(AUC=0.675)had the more larger AUCs.Conclusion CT imaging features especially A1,C1 can be useful to predict the biologic behavior of clear cell renal cell carcinoma for adequate treatment strategy.