The Value Of 3.0t Hr-magnetic Resonance T2-weighted Imaging Combined With Diffusion Weighted Imaging In Rectal Cancer Staging

Objective: To explore the clinical value of 3.0T HR-MRI T2 WI combined with DWI in staging ofrectal cancer.Methods:A total of 67 patients with rectal cancer who were treated in our hospital from May 2020 to December 2021 with the final pathological results as the gold standard were selected as the research subjects.All patients underwent HR-MRI T2 WI and DWI examinations,and underwent surgical treatment within 2 weeks after the examination.According to the pathological tissue,clear T and N clinicopathological staging results were obtained.To compare the diagnostic consistency between HR-MRI T2 WI and HR-MRI T2WI+DWI of rectal cancer in T and N staging and postoperative pathological T staging;To compare the size of the tumor volume（measured on DWI images）of different T and N stages of rectal cancer before surgery;based on DWI images,to comparethe apparent diffusion coefficient（ADC）values of different T stages of rectal cancer before surgery.Results:1.The diagnostic accuracy rate of rectal cancer MRI T2 WI for T staging was 83.58%（56/67）.The diagnostic consistency of MRI T2 WI T staging and postoperative pathological T staging of rectal cancer was excellent（Kappa value=0.802）.2.The diagnostic accuracy of rectal cancer MRI T2 WI +DWI for T staging was89.55%（60/67）,and there was no significant difference between the diagnostic accuracy of rectal cancer MRI T2 WI and T staging（P>0.05）.The diagnostic consistency between T staging of rectal cancer MRI T2WI+DWI and postoperative pathological T staging was excellent（Kappa value=0.881）。3.The diagnostic accuracy of MRI T2 WI of rectal cancer N staging was 64.18%（43/67）.The diagnostic consistency between MRI T2 WI N staging of rectal cancer and postoperative pathological N staging was poor（Kappa value=0.386）.4.The diagnostic accuracy of rectal cancer MRI T2 WI +DWI N staging was77.61%（52 /67）,compared with the diagnostic accuracy of rectal cancer MRI T2 WI for N staging,the difference was statistically significant（P<0.05）.The diagnostic consistency of MRI T2 WI +DWI N staging and postoperative pathological N staging of rectal cancer was high（Kappa value=0.635）.5.On the DWI map,there were significant differences in the tumor volume measured by different T and N stages of rectal cancer before surgery（P<0.05）.and with the increase in the degree of different T、N stages of rectal cancer,the tumor volume measured by DWI showed an increasing trend,and the difference was statistically significant（P<0.05）.6.Based on DWI images,the ADC values measured by different T stages of rectal cancer before surgery showed significant differences（P<0.05）,and with the increase in the degree of T stage of rectal cancer,the ADC value measured by DWI showed a down ward trend,and the difference was statistically significant（P<0.05）.Conclusion:1.HR-MRI T2 WI and MRI T2 WI combined with DWI scanning can both diagnose clinical T staging in patients with rectal cancer well,but the diagnostic consistency of MRI T2 WI for clinical N staging is poor,but combined with DWI scanning can significantly improve the diagnostic consistency,but it has not reached the same level.2.The staging of rectal cancer can be further predicted by measuring tumor volume and ADC value by MRI.