Diagnostic Value Of Multimodality Imaging For Pancreatic Cystic Tumors

Objective1.To investigate the diagnostic value of conventional Ultrasonography(US),Contrast-enhanced Ultrasonography(CEUS)and Magnetic Resonance(MRI)imaging for pancreatic cystic tumor.To provide reference for clinical diagnosis of pancreatic cystic tumor and to evaluate the diagnostic accuracy of US,CEUS and MRI in pancreatic cystic tumor as well to conduct consistency examination.2.Diagnostic value of multimodality imaging for benign and potential malignant tumors of pancreatic cystic lesions3.To explore the application of molecular imaging in the diagnosis of pancreatic cystic tumor,and to study the value of uPAR antibody in the diagnosis of pancreatic cystic tumor by experimental research.Materials and Methods:1.From May 2015 to February 2018,191 patients of pancreatic cystic tumor(97 of 191 were pathlogically confirmed,94 of 191 were clinically confirmed)were enrolled.All the patients had both US and CEUS examination,and 170 of 191 patients underwent MRI scan.(1)To compare the accuracy rate,specificity,sensitivity,and areas under ROC Curve(AUC)of US,CEUS and MRI respectively.(2)To compare the diagnostic accuracy of US,CEUS and MRI for four different types of pancreatic cystic tumor as well to conduct the consistency examination.2.From October 2015 to February 2018,213 patients with cystic lesions of the pancreas were admitted to the General Hospital of the PLA,of which 22 were unable to confirm the diagnosis,and 191 patients had a definite diagnosis.Among them,191 cases underwent CEUS examination,170 cases of MRI examination,130 cases of EUS examination,and 119 cases of CT examination.Among them,82 patients underwent simultaneous ultrasound,nuclear magnetic resonance,CT and endoscopic examination.Of these,76 patients were diagnosed by pathological diagnosis as cystic lesions of the pancreas,and 6 patients were diagnosed by clinical comprehensive diagnosis.This study was divided into two groups:benign and malignant two groups.A combination of images(CEUS,EUS,MRI,CT),two images(CEUS&EUS,CEUS&MRI,CEUS&CT)and three kinds of images(CEUS&EUS&MRI,CEUS&CT&MRI)were used to analyze the differential diagnosis of pancreatic adenosic cystic lesions.3.(1)From February 2016 to February 2018,specimens of cystic lesions of the pancreas(30 cases),pancreatic carcinoma(10 cases)and normal pancreas(40 cases)were collected.To detect the expression of uPAR antibody in pancreatic tissue,the specimens were H&E stained,and conducted immunohistochemistry and cell immunofluorescence.(2)The absorption,fluorescence properties and stability of the tissue in water and serum were studied by UV-visible(UV-VIS)and fluorescence(FL)spectra.CCK-8 cell activity assay kit was used to detect the cell viability of pancreatic cancer cells and normal pancreatic epithelial cells incubated by probe,so as to evaluate the biocompatibility and safety of the molecular probe.(3)After the lesions were removed surgically,the probes were sprayed onto the capsule walls.When the lesions proved to be pancreatic cancer pathologically,the probes were evenly sprayed onto the surface of both tumor tissue and surrounding normal tissues,and then incubated in dark for 10 minutes.According to the fluorescence intensity of different parts,the specimens were obtained from those different parts,and then the pathological experiments were carried out to verify the results.Results:1.(1)The accuracy rate,specificity and sensitivity of US was 61.26%,55%and 65.77%,respectively.The AUC of US was 0.638.The accuracy rate,specificity and sensitivity of CEUS was 79.06%,80.56%and 78.15%,respectively.The AUC of CEUS was 0.815.The accuracy rate,specificity and sensitivity of MRI was 80%,75.93%and 81.90%,respectively.The AUC of MRI was 0.821.The analysis of variance illustrated the accuracy rate,specificity,sensitivity and AUC of US were lower than that of CEUS and MRI significantly(P<0.05).However,when compared with CEUS and MRI,there were no significant difference in accuracy rate and AUC(P>0.05),but the specificity of CEUS was higher than that of MRI,while the sensitivity of CEUS was lower than that of MRI.(2)The diagnostic accuracy of US for MCA,SCA,SPT and IPMN was 50.70%,72.92%,42.11%and 53.57%,respectively.The diagnostic accuracy of CEUS was 71.83%,75%,63.16%and 64.29%,respectively.The diagnostic accuracy of MRI was 73.24%,72.92%,73.68%and 67.86%,respectively.The overall diagnostic accuracy of US,CEUS and MRI for MCA,SCA,SPT and IPMN was 62.25%,70.48%and 72.29%,respectively.The statistical analysis of those results showed the diagnostic accuracy of both CEUS and MRI were significantly higher than that of US(P<0.05).However,there were no significant difference in diagnosis of SCA for the three methods(P>0.05).Also,the diagnostic accuracy of CEUS and MRI for MCA,SPT and IPMN was similar.2.The diagnostic sensitivities of CEUS,EUS,MRI,CT,CEUS&EUS,CEUS&MRI,CEUS&CT,CEUS&EUS&MRI,CEUS&CT&MRI were 68.9%,80.0%,82.2%,75.6%,66.7%,62.2%,60.0%,55.6%,62.2%,respectively;The specificities were 82.9%,94.3%,74.3%,57.1%,97.1%,91.4%,88.6%,91.4%,and 90.2%,respectively;the AUC were 0.759,0.871,0.783,0.663,0.819,0.768,0.743,0.735,respectively.0.811.In the diagnosis of benign,potentially malignant and malignant lesions of pancreatic cystic lesions from 9 types of images,differential diagnosis of benign and malignant EUS(sensitivity 80.0%,specificity 94.3%,AUC 0.871)was used in four single image diagnosis.Preferably,CEUS is comparable to MRI diagnostics.The CT is lower than the other three images.In the combined diagnosis of two images,the combined diagnostic efficiency of CEUS&EUS(sensitivity 66.7%,specificity 99.1%,AUC 0.871)was the highest.In the combined diagnosis of three images,the combined diagnostic efficiency of CEUS&EUS&MRI(sensitivity 62.2%,specificity 100%,AUC 0.811)was the highest.The specificity of CEUS&MRI combined diagnosis is the same as that of CEUS&CT&MRI,lower than that of EUS and CEUS.3.(1)uPAR is highly expressed in pancreatic cancer tissue and lowly expressed in normal pancreatic tissue.For the pancreatic cystic lesions,it is highly expressed in the malignant tumors and lowly expressed in the benign SCAs.(2)The probe is of slight toxicity,and good in biocompatibility and serum stability.It can meet the requirments of the whole research,and it has good active target ability.(3)The optical molecular imaging method based on the target probe can be used to diagnose the properties of pancreatic cystic tumors and it is of great help for clinicians to judge the lesion.Conclusions:1.(1)The diagnostic value of US is much lower than that of CEUS and MRI for common pancreatic cystic tumors.Hence,US can be used to screen the pancreatic cystic disease.(2)There is no significant difference between CEUS and MRI in diagnosis of pancreatic cystic disease.Given the advantages and disadvantages of MRI and CEUS,we should select an optimal method according to the lesion size and patients’specific condition.2.(1)Comprehensive comparison of sensitivity,specificity,and AUC revealed that EUS had the highest diagnostic efficacy and CT had the lowest diagnostic accuracy among the 9 image combinations.(2)The joint diagnosis of CEUS&CT&MRI images and the CEUS&MRI images have the same specificity and the AUC value is reduced.Therefore,the patient can perform CTUS and MRI examination without CT examination.Although the specificity of CEUS&EUS&MRI and CEUS&EUS has been improved,the AUC has been reduced.From the examination cost,CEUS and EUS can be performed first.(3)The combined diagnosis of CEUS&MRI and CEUS&CT combined showed a significant increase in specificity compared with single MRI and CT.Therefore,for patients with limited EUS examinations,CEUS&MRI can be used as a combination of CEUS&MRI and CEUS&CT.3.The expression of target probe in normal pancreatic tissue and lesion tissues is different from each other.In the meantime,it is proved that the probe has the advantages of slight toxicity,good biocompatibility and good serum stability,and it has good active targeting ability.It is applicable for the study of molecular imaging diagnosis of pancreatic cystic lesions.