Analysis On The Application Value Of MRI In Preoperative T-staging Of Rectal Cancer

Object:To evaluate the application value of MRI in preoperative T-staging of rectal cancer。 Materials and methods:138 patients with primary rectal cancer that had been hospitalized in the gastrointestinal colorectal anal department of China–Japan Union Hospital of Jilin University from September 2014 to December 2015 were included in the study.All patients received electronic fiber colonoscopy examination before the operation and were diagnosed with rectal cancer.All patients received surgery treatment in 1-6 days after nuclear magnetic resonance MRI examination and then received postoperative pathological examination.Radical resection of rectal carcinoma was conducted by following principles of total mesorectum resection Operations included laparoscopic surgery and traditional open surgery and the operation ways included Dixon and Miles,etc.All resected tissue samples were soaked and fixed in formalin for half an hour and were observed by two experienced physicians from the pathology department.Nuclear magnetic resonance images were read by two senior physicians of radioactive rays,respectively.There were 72(52.17%)male cases and 66(47.83%)female cases,with the age range of 30-90 years old,averagely 58.60 years old.Postoperative pathologic staging of rectal cancer was taken as the standard to evaluate the accuracy of T-stages of preoperative MRI,and influences of relationship between tumor and peritoneal foldback.Results:Post-operative pathology staging results of all patients: 4 cases in T1 stage,24 cases in T2 stage,102 cases in T3 stage,and 4 cases in T4 stage.Histopathology staging T stages after rectal cancer surgery: 6 cases in T1 stage,30 cases in T2 stage,98 cases in T3 stage and 4 cases in T4 stage.Among 138 patients,T staging of pre-operative MRI examination of 108 cases were consistent with T staging of postoperative pathology T staging,with the accuracy rate of 78.26%.T1 staging accuracy rate 66.67%(4/6),T2 staging accuracy rate 46.67%(14/30),T3 staging accuracy rate 87.76%(86/98),T4 staging accuracy rate 100.00%(4/4).30 cases had inconsistent results with postoperative pathology T staging,among them,8 cases with lower staging,with the proportion of 26.67% and 22 cases with higher staging,73.33%.Consistency check of MRI and pathology T staging Kappa=0.500.There were 35 cases of tumor recurrence in the peritoneal fold,and 29 cases were consistent with the postoperative pathological T staging.The accuracy rate was 82.86%.There were 103 cases under the peritoneal foldback,of which 79 cases were consistent with the preoperative MRI T staging,the accuracy rate was 76.70%.There was no statistically significant difference between them(X2=1.106,P>0.05).Conclusions:MRI pre-operative T staging of rectal cancer has a good consistency with pathological T staging and MRI is of high application value in preoperative T staging of rectal cancer.MRI has a high value in the T stage of rectal cancer,especially advanced rectal cancer,and can be used to guide clinical treatment.Its application is not affected by the relationship between tumor and peritoneal foldback.