Application Of Magnetic Resonance Imaging In Preoperative Staging Of Rectal Cancer And Its Correlation With ADC Value And Differentiation Of Rectal

Part1The value of Enema Glycerine applying in preoperative MRI T1staging and T2staging of rectal cancerObjective:To evaluate the value of Enema Glycerine applied in preoperative MRI T1staging and T2staging of rectal cancer.Materials and Methods:The MRI datum of81cases of biopsy-pathologically confirmed rectal cancer suffers, and pathologically confirmed T1staging or T2staging of rectal cancer suffers after operation(50males and31females whose ages,64.2±12.2on average, range from31to88), were collected retroactively, from September2005to December2013, in PUMCH. Approved by an ethical committee and with informed consents signed, patients involved in the study were examined by MRI within two weeks before the operation.In this study, the patients examined from June2012to December2013, containing45cases (30males and15females whose ages,63.4±13.7on average, range from31to82), had used the Enema Glycerine. The other examined from September2005to May2012, including36cases (21males and15females whose ages,65.6±11.5on average, range from35to88), had no used it. So these cases were assigned to two groups. Furthermore, the thesis compared the preoperative MRI examination results to the postoperative pathological staging, applied the diagnostic testing statistic method, calculated the sensitivity, specificity and accuracy, positive predictive value and negative predictive value of the MRI T1staging, T2staging, and the the sensitivity of T1+T2staging, respectively, and utilized Kappa test to analyze the consistency of both the MRI T staging and preoperative pathological staging every group.Results:Kappa tests (k=0.693and k=0.537) showed the two groups, including applying the Enema Glycerine and no applying the Enema Glycerine, have good consistency of the MRI T staging and the preoperative pathological staging. Respectively, in the group applying the Enema Glycerine, the sensitivity,specificity and, accuracy, positive predictive value and negative predictive value of the MRI T1staging are76.5%,92.9%,86.7%,86.7%and86.7%; those of the MRI T2staging are78.6%,76.5%,86.7%,84.5%and68.4%; the sensitivity of the MRI T1+T2staging is77.8%. In the other group, no applying the Enema Glycerine, the sensitivity, specificity and, accuracy, positive predictive value and negative predictive value of the MRI T1staging are57.1%,95.5%,80.6%,88.9%and77.8%; those of the MRI T2staging are77.3%,57.1%,69.4%,73.9%and61.5%; the sensitivity of the MRI T1+T2staging is69.4%. The statistic analysis show the sensitivity of the MRI T1staging, the specificity and accuracy of the MRI T2staging of the group applying the Enema Glycerine are higher than that of the group no applying the Enema Glycerine (P<0.05, single-side hypothesis testing)Conclusion:There is higher value of Enema Glycerine, which can significantly improve the sensitivity of the preoperative MRI T1staging, the specificity and accuracy of T2staging,and simultaneously improve partly the diagnosis accuracy of the MRI T1staging and T2staging, applied in preoperative MRI T1staging and T2staging of rectal cancer and thus it should be one of the conventional application. Part2Comparative study of the value between3T MRI and1.5T MRI applying in preoperative diagnosis of the invasion of rectal cancer in the fat around rectumObjective:To compare the value between3T MRI and1.5T MRI applying in preoperative diagnosis of the invasion of rectal carcinoma in the fat around rectum. Materials and Methods:The MRI datum of79cases of biopsy-pathologically confirmed rectal cancer suffers, and pathologically confirmed T2staging or T3staging of rectal cancer suffers after operation(49males and30females whose ages,65.3±11.6on average, range from32to87), were collected retroactively, from May2012to february2014, in PUMCH. Approved by an ethical committee and with informed consents signed, patients involved in the study were examined by MRI within two weeks before the operation.In this study,29cases of the patients were examined by3T MRI from May2013to february2014(16males and13females whose ages,64.7±11.3on average, range from32to81), and the other, containing50cases, were examined by1.5T MRI from May2012to february2014(33males and17females whose ages,65.5±11.8on average, range from34to87). So these cases were assigned to two groups. Furthermore, the thesis compared the preoperative MRI examination results to the postoperative pathological staging, applied the diagnostic testing statistic method, calculated the sensitivity, specificity and accuracy, positive predictive value and negative predictive value of MRI T2staging and T3staging, respectively, and utilized Kappa test to analyze the consistency of both the MRI T staging and preoperative pathological staging every group.Results:Kappa tests of3T MRI and1.5T MRI(k=0.712and k=0.689)showed the two groups, which of3T MRI and which of1.5T MRI, have good consistency between the MRI T staging and the preoperative pathological staging. Respectively, in the group applying3T MRI, the sensitivity, specificity and accuracy, positive predictive value and negative predictive value of MRI T2staging are90.9%,94.4%,93.1%,90.9%and94.4%; those of MRI T3staging are94.4%,90.9%,93.1%,94.4%and90.9%. In the other group, applying1.5T MRI, those of MRI T2staging are71.4%,81.8%,76.0%,83.3%and69.2%; those of MRI T3staging are81.8%,78.6%,80.0%,75.0%and84.6%. The statistic analysis show the sensitivity, specificity and accuracy of MRI T3staging and MRI T2staging in the group applying3T MRI are higher than that of the group applying1.5T MRI (P<0.05, single-side hypothesis testing)Conclusion:There is higher value of3T MRI than1.5T MRI, which can improve the diagnosis accuracy of the invasion of rectal carcinoma in the fat around rectum(with invasion, which is T3staging of rectal cancer; with no invasion, T2staging), applied in preoperative examination of rectal cancer and thus the diagnostic reference standard of MRI signs of local infiltration of rectal cancer put forward in this study is, to some extent, valuable and helpful to the evaluation of the extent of the circumference invasions of rectal carcinoma in the fat around rectum. Part3A correlative study between ADC value and the differentiation of rectal adenomatous carcinoma Objective:To investigate the correlation between ADC value and rectal mucinous adenocarcinoma, rectal adenomatous carcinoma in differentiated degree.Materials and Methods:The MRI datum of88biopsy-pathologically confirmed rectal cancer suffers, and pathologically confirmed suffers of rectal mucinous adenocarcinoma or rectal adenomatous carcinoma in differentiated degree (51males and31females whose ages,65.8±13.1on average, range from35to87), were collected retroactively, from May2012to February2014, in PUMCH. Approved by an ethical committee and with informed consents signed, patients involved were examined by MRI within two weeks before the operation. This study included31rectal mucinous adenocarcinoma accounting for10.2%and79rectal adenomatous carcinoma in differentiated degree, containing Well-differentiated adenocarcinoma (including13Medium-high differentiation tumors), Moderately differentiated adenocarcinoma and poorly differentiated adenocarcinoma, which are31,40and8cases respectively. All patients underwent1.5T MRI scan including DWI sequence (b=1000s/mm2), and ADC value of the lesions were measured on GE AW4.3MRI workshop, which were then compared statistically between different pathological types and different differentiated types.Results:ADC value of rectal mucinous adenocarcinoma was (1.362±0.124)×10-3mm2/s; ADC value of rectal adenomatous carcinoma was (0.949±0.146)×10-3mm2/s. The differences above were statistically significant (P<0.05).ADC values of in well, moderately and poorly differentiated adenomatous carcinoma were (1.129±0.128)×10-3mm2/s,(0.865±0.143)×10-3mm2/s,(0.672+0.196)×10-3mm2/s respectively. ADC values in any two groups were statistically significant (P<0.05)Conclusion:ADC value are helpful in identifying rectal mucinous adenocarcinoma from rectal adenomatous carcinoma. ADC values of rectal adenomatous carcinoma is positively correlated with the degree of differentiation.