Twenty-eight patients with colon carcinoma (excluding the recto-sigmoid region) underwent preoperative staging with computed tomography (CT). The CT had a sensitivity and a specificity of 60 and 67% for detection of extramural invasion, 75% sensitivity and specificity for lymph node metastases and a sensitivity of 87% and specificity of 95% for liver metastases. Compared with the modified Dukes classification, CT correctly staged 50% of the patients with Dukes A lesions; 40% with Dukes B; 75% with Dukes C and 85% with Dukes D lesions. The data presented in this study showed that CT has limitations in the sensitivity and accuracy of staging local colonic carcinoma. However, we recommend its use for patients who are clinically suspected of having extensive disease.