Preliminary Application Of Shear Wave Elastography In Grading Of Bladder Urothelial Carcinomaand Its Correlation With Collagen Fibers

Objective:1.To explore the different features between low grade papillary urothelial carcinoma(LGPUC)and high grade papillary urothelial carcinoma(HGPUC)in two-dimensional ultrasound,and to explore the application value of shear wave elastography(SWE)in grading of bladder urothelial carcinoma.2.To investigate whether there was a difference in collagen fibers content between the bladder cancer tissues of two groups,and to analyze the correlation between collagen fibers content and elasticity modulus value of the tumor tissues of two groups.Methods:1.There were 102 patients diagnosed as bladder tumors were collected from the first affiliated hospital of Nanchang university.Applying transrectal or vaginal exploration of intravesical tumors,and recording the two-dimensional features of the tumor.The maximum value of elasticity(Emax),mean value of elasticity(Emean)and minimum value of elasticity(Emin)of bladder tumor were measured by SWE technique.36 patients were excluded,and 66 patients were included in the analysis.According to the pathological results,34 patients were divided into LGPUC group,32 patients were divided into the HGPUC group.The two-dimensional ultrasonic features such as location of the mass,internal echo,base condition,number,surface condition,color flow were observed,and the Emax,Emean,and Emin of bladder urothelial carcinoma between two groups were measured by SWE.2.Masson staining of the pathology specimens of 66 patients were evaluated postoperation.Three low-magnification microscopes(×40)with cancer tissue structure were randomly selected from each slice under electron microscope.Image-Pro Plus 6.0 software system was used to calculate the percentage of collagen fiber area in the visual field.The percentage of collagen fiber area in the three visualfields was added to calculate the average value of collagen fibers.Investigating whether there was a difference in percentage of collagen fiber area between the two groups,and analyzed the correlation between percentage of collagen fiber area and elasticity modulus value of the two groups.Results:1.There were no significant differences in the location,internal echo,basal condition,number,color flow and size between the two groups(p>0.05).The surface condition of the two groups of tumors was statistically different(p<0.05).Emax and Emean of bladder cancer of HGPUC group were significantly higher than LGPUC group(p<0.05),but there was no significant difference of Emin between two groups(P>0.05).The receiver operating characteristic curves(ROC)of Emax and Emean were respectively divided.The best cut-off point for identifying HGPUC and LGPUC of Emax and Emean of bladder cancer was 14.33 kPa and 10.07 kPa.The area under the curve(AUC)was 0.86 and 0.85.2.The percentage of collagen fiber area of two groups were statistically different through statistical analysis.HGPUC group was more than LGPUC group.There was a positive correlation between the percentage of collagen fiber area and the elasticity modulus value of the tissue.Conclusion:1.Two-dimensional ultrasound was difficult to realize the accurate classification of bladder urothelial carcinoma before surgery.SWE technology could quantify the elasticity of bladder tumors and had certain application value in identification of LGPUC and HGPUC.2.The percentage of collagen fiber area of LGPUC and HGPUC were different.There was a positive correlation between percentage of collagen fiber area and elasticity modulus value of the tumor tissue in two groups,indicating that the collagen fiber content had an important influence on the hardness of bladder cancer tissue.It suggested that collagen fibers had involved in the development of bladder urothelial carcinoma.