Value Of IVIM-MRI Combined With DCE-MRI In Assessing The Infiltration Boundary Of Soft Tissue Sarcoma Based On Image-pathology Comparison

Purpose:In order to reveal the correlation between IVIM-MRI and DCE-MRI parameters of soft tissue sarcoma and its pathological changes through image-pathology comparison method.The ultimate goal was to explore the value of IVIM-MRI and DCE-MRI in judging the infiltration boundary of soft tissue sarcoma.Materials and Methods:1.Patient informationA total of 90 patients suspected of being soft tissue tumors in the Second Hospital of Dalian Medical University from January 2019 to February 2020 were collected.The pathological results of 35 patients were soft tissue sarcomas.Finally,based on the inclusion and exclusion criteria,12 patients were selected for the group,including 7 males and 5 females,with an average age of 56.5 years.2.MRI examination and image post-processing?1?Conventional MRI examination: GE Discovery 750 W 3.0T MRI scanner equipped with ADW4.7 workstation,Functool and Gen IQ post-processing software was used for examination.Conventional MRI imaging sequences included: T1 WI,T2WI.?2?IVIM-MRI acquisition: EP-DWI sequence was used,b = 0,25,50,75,100,200,500,800s/mm2.?3?DCE-MRI acquisition: The LAVA sequence was used for imaging.The first plain scan was performed 3 times,and the fourth time the high pressure syringe was used to inject gadopentetate glucosamine through the elbow vein.In the end,a total of 48 scans were performed.?4?Post-processing and data acquisition of IVIM-MRI and DCE-MRI images: Functool software was used to obtain the pseudo-color image corresponding to the IVIMMRI quantitative parameters Standard ADC,D,D^*,and f values.Gen IQ software was selected for quantitative analysis of DCE-MRI images,and the dual-chamber model was used for the hemodynamic model to obtain pseudo-color images corresponding to K^trans,K_ep,and V_e values.Finally,the Region of Interest?ROI?was manually selected to obtain parameter values.3.MRI-pathological control method?1?Body surface positioning mark?2?MRI examination?3?Positioning during surgery?4?STS pathological materials4.Observation indicators?1?MR imaging index?1?Conventional MRI signs: tumor size,location,morphology,presence or absence of capsules,and abnormal signals around the tumor;?2?IVIM-MRI parameters: Standard ADC value,D value,D * value,f value;?3?DCE-MRI parameters: K^trans value,K_ep value,V_e value.?2?Pathological indicators?1?Tumor cell morphology;?2?Whether there was an envelope around the tumor;?3?Whether there was tumor cell infiltration in the surrounding tumor tissue.5.Statistical analysisData analysis was performed using SPSS 21.0 statistical software.?1?The IVIM-MRI and DCE-MRI parameters were tested for compliance with thenormal distribution.The compliance with the normal distribution was expressed bythe mean ± standard deviation?x ± s?.The measurement data for non-normaldistributions were represented by median(P₂₅,P₇₅)Means;?2?When the normal distribution data and the variance were the same,the IVIM-MRI and DCE-MRI parameters were compared between the soft tissue sarcomanegative invasion group and the positive infiltration group using independent samplet test,and the non-normal distribution data were used Wilcoxon rank sum test;?3?Receiver Operator Characteristic Curve?ROC?was used to analyze the diagnosticefficacy of parameters that are meaningful for identifying the presence of tumor cellinfiltration around STS.Results:1.MRI manifestations of soft tissue sarcoma?1?Conventional MRI signs of soft tissue sarcoma?1?Location: 5 cases intramuscularly,5 cases subcutaneously,and 2 cases of muscle space;?2?Size: 9 cases had the largest tumor diameter> 5cm,and 3 cases had <5cm;?3?Morphology: 6 cases were irregular,6 cases were round;?4?Strengthening method: 10 cases with obvious uneven strengthening and 2 cases with mild strengthening;?5?Envelope: There were 4 cases with envelope and 8 cases without envelope.?2?IVIM-MRI and DCE-MRI signs of soft tissue sarcomaIVIM-MRI: 12 cases of soft tissue sarcoma IVIM-MRI showed mixed high signals,which could be seen from the b value-signal curve.As the b value increased,the signal intensity in the mass decreased.DCE-MRI: It could be seen from the time-signal curve that 9 cases showed a rapid rise platform type and 3 cases showed a slow rise type.?3?MRI signs of STSs around the tumorT2WI around the tumor was slightly higher in 12 cases of STS,and 6 cases showed enhanced signs around the tumor.IVIM-MRI indicated that the abnormal area around the tumor showed a high signal,and the signal intensity decreased with the increase of b value.In the DCE-MRI TIC curve around the tumor,2 cases showed a rapid rise plateau type and 10 cases showed a slow rise plateau type.2.Pathological observation of soft tissue sarcoma?1?Tumor cell morphology: 8 cases were polymorphic,4 cases were spindle or short spindle;?2?Peritumoral envelope: 6 cases with envelope and 6 cases without envelope;?3?Results of peritumoral invasion: Twelve cases of STS were divided into two groups,and finally 7 cases of positive infiltration group,a total of 37 sites were observed;5 cases of negative infiltration group,a total of 25 sites were observed.3.Correspondence between MRI observation area of soft tissue sarcoma and pathological manifestation under microscope?1?Correspondence between MRI and pathology in the soft tissue sarcoma peripositive invasion group?2?Correspondence between MRI and pathology in the soft tissue sarcoma perinegative invasion group4.Comparison of IVIM-MRI parameters of soft tissue sarcoma and its infiltration results?1?Comparison of IVIM-MRI parameters between the negative and positive infiltration groupsIn 12 patients with STS,the IVIM-MRI parameters of Standard ADC and D values were significantly different between the negative and positive infiltration groups?P <0.05?.The Standard ADC values and D values of the positive infiltration group were lower than those of the negative infiltration group.There were no significant differences in D^* value and f value between the negative and positive infiltration groups?p> 0.05?.?2?The diagnostic efficacy of IVIM-MRI parameters Standard ADC value and D value for tumor infiltrationThe areas under the curve of the Standard ADC value and D value for the diagnosis of peritumoral infiltration of soft tissue sarcoma were 0.742 and 0.854,and the diagnostic thresholds were 1.945 and 1.800.At this time,the corresponding sensitivities were 72% and 92%,and the specificities were 73%,77%.5.Comparison of DCE-MRI parameters of soft tissue sarcoma and its infiltration resultsComparison of DCE-MRI parameters between the negative and positive infiltration groups: There were no significant differences in the K^trans value,K_ep value,and V_e value of the DCE-MRI parameters of the STS between the negative and positive infiltration groups?p> 0.05?.Conclusion:Based on the image-pathology control method,through the quantitative analysis of MRI functional imaging IVIM-MRI,DCE-MRI and the final pathological results of 12 cases of soft tissue sarcoma,the following conclusions could be drawn:1.When the Standard ADC value and D value were 1.945 x10-3mm2/s and 1.800 x10-3mm2/s,respectively,the sensitivity of this threshold to differential diagnosis of soft tissue sarcoma negative and positive infiltration groups was 72% and 92%,respectively.The specificity was 73% and 77%,respectively.Among them,the D value had the best diagnostic efficacy,and the D^* value and f value could not distinguish between tumor infiltration and simple reactive edema.2.The quantitative parameters of DCE-MRI,such as K^trans value,K_ep value and V_e value,could not distinguish between soft tissue sarcoma infiltration or simple reactive edema.3.According to the threshold ADC and D values of the soft tissue sarcoma peritumor to distinguish tumor infiltration or simple reactive edema,and find the corresponding ROI position of the MRI sequence,the boundary of soft tissue sarcoma peritumoral invasion can be judged.