Diagnostic imaging in staging of colorectal cancer

The main strength of MR is the ability to define the mesorectal facia. There is recent evidence suggesting that MR imaging can accurately predict the tumor-free circumferential resection margin before total mesorectal excision. However, the prediction of T stage is less accurate and more affected by the experience of the observer. Transrectal ultrasonography has proven useful for staging of rectal carcinoma. Computed tomography is one of the most useful imaging techniques for the evaluation of metastatic lesions in colorectal cancer.