Computer tomography (CT) has been the principal investigation in the staging of colon cancers. The information obtained with routine CT has been limited to identifying the site of the tumour, size of the tumour, infiltration into surrounding structures and metastatic spread. Several studies have questioned the routine use of preoperative CT scanning for staging colonic cancers owing to its limitations in altering surgical management. In this lecture, a quite clear exposure of the role of preoperative CT-scan in predicting "good" and "poor" prognostic features in colonic cancer is exposed.