Correlation Of DCE-MRI With MVD And VEGF Expression In Soft Tissue Sarcomas

Objective: To explore the relationship between imaging characteristics ofcontrast-enhanced MR imaging (DCE-MRI) and MVD,VEGF of soft tissue sarcomas(STSs).Materials and methods:1. Case data: Thirty cases (aged18-80, mean52.6years) of STS were analyzed fromMarch2013to January2014, including Liposarcoma, Mucus fibrosarcoma, Synovialsarcoma, Malignant fibrous histiocytoma, Angiosarcoma, Chondrosarcoma,Leiomyosarcoma, Myeloid sarcoma, Myofibroblastic tumor malignant andUndifferentiated sarcoma.2. MR scanning positioning, technology, image post-processing:(1) MR scanning positioning: we draw a tag line(marking1)on the surface of tumorwhich overlap with zero positioning of machine before scaning. Then conducted axialscan with routine and dynamic contrast-enhanced.After scanning we used Functoolsoftware to find the most obvious strengthen area of the tumor, and calculated thedistance and draw the second tag line on the surface of the patient(marking2).(2) MR technology: DCE-MRI aplaying2D fast spoiled gradient echo sequence(2DFSPGR), contrast agent Magnevist (0.1mmol/kg), and then continuous scanning16phase.(3) Image post-processing: Time-intensity curve (TIC) and quantitative parametersof tumor in different series were analyzed. 3. Specimen preparation and obtain tissue sections(1) Specimen preparation: cutting along the marking2, the tumor was markeddifferent munber of wire around to distinguish orientation after removing the tumor.(2) The preparation of tissue section: pathology doctors took out the tumor tissue,contrast of DCE-MRI images to identify the point of the most enhanced from twodirections and cut out the tumor tissue. we will make paraffin blocks of tumor tissue and2μmthick slices.4. Immunohistochemical: ready-to-mouse anti-human CD34monoclonal antibody;rabbit anti-human vascular endothelial growth factor monoclonal antibody; ready to usequick immunohistochemical MaxVisionT Mdetection kit.5. Imaging-Pathologic correlation: preoperative: we get the enhangced imaging, MSIand SER pseudocolor, TIC curve by Functool automatic analysis software. We canrespectively controlled study of TIC and immunohistochemical indicators(CD34,VEGF).6. Observational indexes:(1) TIC types of STSs: There are four types of TIC: I (flat type), II (slowly risingtype), III (speed up flat type) and IV (speed up falling type).(2) The characteristics parameters of the DCE-MRI: we choose eight parameters:Maximum Slope of Increase(MSI), the relative Maximum Slope of Increase (rMSI),Signal Enhancement Ratio(SER), the relative Signal Enhancement Ratio (rSER),Signal Intensity of Peak (SIpeak), Time of Peak (Tpeak),△Tpeak，Signal EnhancedExtent（SEE）.(3) MVD, VEGF: We find the vascular are at a low power lens(×40), and then wetake a count of the number of vessels at a high power lens (×400) to MVD countingmethod be adopted Weidner. Evaluation of VEGF expression by using the method ofXu Liang zhong. Divided into four levels of expression (－,+,++,+++).5. Statistical analysis: All cases of data we analyzed we were using SPSS statisticalanalysis software(version19.0).(1) We used the single factor analysis of variance to analysis the differences of TIC types and MVD of STSs, pairwise comparisons using LSD method.(2) We used Kendall,s tau-b rank correlation to analysis the correlation between TICtypes and VEGF expression levels.(3) We used the single factor analysis of variance to analysis the differences ofVEGF expression levels and MVD of STSs, pairwise comparisons using LSD method.(4) The correlation between DCE-MRI parameters and MVD of30cases of STSswas used Pearson correlation method;(5) The correlation between DCE-MRI parameters and VEGF expression levels wasused Spearman correlation method.Results:1.Compare with TIC types and MVD of STSs: Within the30cases of STSs,7casesshow type II, mean of MVD was14.11±3.22,13cases show type III, mean of MVDwas19.03±3.65,10cases show type IV, mean of MVD was25.26±8.99. There aresignificant differences among the three groups of MVD. There are differences of MVDbetween type II and type IV(p=0.001); there are differences of MVD between type IIIand type IV (p=0.019); type II and type III no statistical difference.2.Compare with TIC types and VEGF expression levels of STSs: TIC types andVEGF expression levels are positively correlated with statistical significance(p=0.007);3. Compare with VEGF expression levels and MVD: there are obvious differences ofMVD in the different expression levels of VEGF(p=0.006). there are differences ofMVD in－and+++of VEGF expression levels; there are differences of MVD in+and+++; there are differences of MVD in++and+++.4. The correlation between DCE-MRI parameters and MVD of STSs:rMSI positivecorrelated with MVD(p＜0.001),there is statistically significant. Others(MSI,SER,rSER,SEE,Tpeak,△Tpeak) have no correlation with MVD.5. The correlation between DCE-MRI parameters and VEGF expression levels: MSI，rMSI，SER，rSER，SEE，Tpeak，△Tpeak，SIpeak have no correlation with VEGFexpression levels. Conclusions:TIC types may indicate number of the MVD and level of the VEGF expression. rMSIof CE-MRI may be related to the expression level of MVD, which is relevant to reflectthe biological behavior.