IVIM?DKI And ASL In The Diagnosis And Differential Of Clear Cell Renal Cell Carcinoma

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Intravoxel incoherent motion and diffusion kurtosis imaging in the assessment of pathological grades of clear cell renal cell carcinomaObjective:To evaluate the diagnostic value of intravoxel incoherent motion(IVIM)and diffusion kurtosis imaging(DKI)parameters for clear cell renal cell carcinoma(ccRCC)grading.Methods:60 patients with ccRCC admitted to our hospital from October 2017 to July 2019 were retrospectively analyzed.According to Fuhrman grading,the patients were divided into the low-grade group(?+?)and high grade group(?+?).All MR experiments were performed at a 3.0T MR system(Discovery 750,GE Healthcare,USA).All subjects underwent IVIM and DKI imaging after the corresponding T2 weighted anatomical images were acquired.All acquired IVIM and DKI data were separately analyzed using IVIM and DKI post-processing software developed under the Functool platform on GE ADW4.6 workstation.Using the Bi-exponential decay model,the IVIM related parameters including apparent diffusion coefficient(ADC),true diffusivity(D),pseudo-diffusion coefficient(D*)and perfusion fraction(f)were calculated.Additionally,the DKI related parameters of mean diffusivity(MD)and mean kurtosis(MK)were also obtained.Each region of interest(ROI)was placed at a solid area of the tumor on a representative slice with reference to T2-weighted images to exclude necrosis,cysts,hemorrhage,large vessels,edema,and calcifications.ROI values for all parameters were measured three times and the corresponding mean values were obtained for data analysis.Statistical analyses were performed using SPSS(version22.0).Each parameter(ADC,D,D*,f,MK,MD)was compared between high-grade and low-grade ccRCC using Mann-Whitney U test.Receiver-operating characteristic analysis was also performed for all parameters to evaluate the diagnostic performance.Significance threshold was set as P<0.05.Results:37 low-grade patients(median age,52 years old;range,31-63 years old)and 23 high-grade patients(median age,61.5 years old;range,38-81 years old)were included for data analysis.ADC,D and MD values were significantly lower for high-grade ccRCC compared to low-grade ccRCC(P<0.05).MK values were significantly higher in high-grade ccRCC compared to low-grade ccRCC(P<0.05).However,D*and f were not significantly difference between the two groups(P>0.05).MD had the largest area under the curve(AUC=0.888),followed by ADC(AUC=0.796),D(AUC=0.780),MK(AUC=0.736),f(AUC=0.582)and D*(AUC=0.533).Conclusion:Our study demonstrated that diffusion-related parameters(ADC,D,MD and MK)can be used to accurately differentiate low-and high-grade ccRCC.MD with the largest AUC might be the optimal indicator for ccRCC grading.Part ? Differentiation between fat-poor angiomyolipoma and clear cell renal cell carcinoma using arterial spin labeling MR imagingObjective:To assess the diagnostic effectiveness of arterial spin labeling(ASL),as a magnetic resonance imaging(MRI)technique,in differentiating fat-poor AML from clear cell renal cell carcinoma(ccRCC).Methods:29 ccRCC patients and 9 fat-poor AML patients confirmed by postoperative pathology,who underwent MRI scan preoperatively,were analyzed retrospectively.All acquired 3D ASL images were processed using Functool software on ADW4.6 workstation.The parameters of tumor blood flow(TBF),contralateral normal renal cortex(RC)blood flow and contralateral normal renal medulla(RM)blood flow were measured.Two normalized tumor blood flow(nTBF(RC)=TBF/BFRC?nTBF(RM)=TBF/BFRM)were calculated.Statistical analyses were performed using SPSS(version22.0).Independent sample t-test was used to evaluate the difference of TBF,nTBF(RC),and nTBF(RM)between the fat-poor AML and ccRCC groups.Areas under the ROC curve(AUC)s required for the discrimination were separately calculated for each metrics.Results:TBF and nTBF were significantly higher in ccRCC group than that in fat-poor AML group(270.49±78.88vs146.68±47.21,1.22±0.26vs0.74±0.14,3.13±0.94vs1.77±0.55;P<0.05).Both nTBF(RC)and nTBF(RM)were notably higher in ccRCC group compared with those in fat-poor AML group(1.22±0.26 vs.0.74±0.14,3.13±0.94 vs.1.77±0.55;P<0.05).The areas under the ROC curve for TBF,nTBF(RC)and nTBF(RM)were 0.931,0.964,and 0.900,respectively.No significant difference was observed in AUC values of these three metrics.The best critical value of TBF for distinguishing ccRCC and fat-poor AML was 204.22ml/100g/min,the sensitivity and the specificity were 79.31%and 100%respectively.The best critical value of nTBF(RC)to differentiate these two kinds of tumors was 0.94,the sensitivity and the specificity rate were 93.10%and 100%respectively.The best critical value of nTBF(RM)to differentiate these two kinds of tumors was 2.3,the sensitivity and the specificity were 82.76%and 88.89%respectively.Conclusion:ASL MRI has high clinical value as a non-invasive method in differential diagnosis of fat-poor AML from ccRCC.Part ? Application value of arterial spin labeling technique in assessment of pathological grade of clear cell renal cellObjective:To evaluate the value of arterial spin labeling(ASL)in assessment of pathological grade of clear cell renal cell carcinoma(clear cell renal cell carcinoma,ccRCC).Methods:The ASL data of 36 patients with ccRCC admitted to our hospital from January 2018 to January 2019 were retrospectively analyzed,and the ccRCC cases were graded using Fuhrman grading system,including 19 cases of low-grade(?+?),17 cases of high-grade(?+?).The parameters of tumor blood flow(TBF)?contralateral normal renal cortex(RC)blood flow,and contralateral normal renal medulla(RM)blood flow were measured.Two normalized tumor blood flow(nTBF)[nTBF(RC)=TBF/BFRC?nTBF(RM)=TBF/BFRM]were calculated.Mann-whitney test were used between groups of low-grade and high-grade ccRCCs.Receiver operating characteristic(ROC)analyses were conducted to determine the sensitivity and specificity for grading results.Results:TBF and nTBF were higher in the high grade ccRCC group than that in the low grade ccRCC group(242.4±39.26vs184.93±54.83,1.31±0.28vs0.94±0.22,3.44±1.35vs2.22±1.32).There were significant differences found(all P<0.05).Areas of TBF,nTBF(RC)and nTBF(RM)values under ROC curves to diagnose low and high grade cancers were 0.826?0.906 and 0.770.The best critical value of TBF for distinguishing high-grade ccRCC and low-grade ccRCC was 203.78ml/100g/min,the sensitivity and the specificity were 72.7%and 88.2%respectively.The best critical value of nTBF(RC)to differentiate these two kinds of tumors was 1.06,the sensitivity and the specificity rate were 77.3%and 94.1%respectively.The best critical value of nTBF(RM)to differentiate these two kinds of tumors was 2.08,the sensitivity and the specificity were 54.5%and 94.1%respectively.Conclusion:ASL may provide useful information in the grading of CRCCs preoperatively.It can be used as a new and noninvasive imaging method in the grading of ccRCC.It can very important in patients with renal function insufficientcy and ccRCCs patients follow up.