Preoperative local staging of primary rectal cancer:comparison of CT and MRI

Objective The purpose of this study was to compare the accuracy of CT and MRI in the preoperative local staging of primary rectal cancer.Methods 25patients with rectal cancer proved surgically and histologically were studied.Each of patients underwent CT and MRI examination before surgical operation.CT study included plain and contrast enhanced scanning.MRI study included Sagittal T2WI,coronal T2WI,axial T1WI and T2WI,axial DWI sequences.The depth and extent of tumor infiltration of the intestinal wall,surrounding infiltration,and lymph nodes around the rectum were observed.The preoperative staging results were compared with those of postoperative pathological staging.Results In the preoperative T staging,the overall accuracy rates of CT and MRI were 72.0%(weightedκ=0.426)and 88%(weightedκ=0.760),respectively.In the preoperative N staging,the accuracy rates of CT and MRI were 72.0%(weightedκ=0.426)and 84.0%(weightedκ=0.675),respectively.Conclusion In preoperative local staging of primary rectal cancer,MRI was superior to CT.