Pre-operative MRI evaluation of local disease extent in residual / recurrent colorectal and anal cancer

ABSTRACT

To determine pre-operative MRI accuracy in assessing local disease extent in residual / recurrent colorectal and anal cancer by comparing MRI assessment and staging examination under anaesthesia, Eighteen consecutive patients with recurrent [12 patients] or residual [6 patients] underwent examination under anaesthesia and MRI using a phased array pelvic coil. .Analysis of eight specific anatomical regions for tumor involvement on MRI was performed Findings at examination under anaesthesia and biopsy were recorded. The MRI and examination under anaesthesia findings were correlated with findings at surgery and histopathology. MRI accuracy in determining tumor invasion for all sites assessed were [90%,], sensitivity was [85%,], specificity was [91%], positive predictive value [PPV] was [75%] and negative predictive value [NPV] was [95%]. For those anatomical sites evaluated by both examination under anaesthesia and MRI, MRI was superior to examination under anaesthesia, with an accuracy of 90% Vs 74%. MRI is an accurate technique for assessing disease extent in recurrent / residual colorectal and anal cancer