BackgroundThis study aimed to assess the usefulness of computed tomographic colonography (CTC) in preoperative evaluation of colorectal tumors and the entire bowel including endoscopically inaccessible regions.MethodsColonoscopy and CTC were performed for 49 patients. The tumor and the entire colon were assessed, and the results were compared with colonoscopy. The extraluminal findings of CTC were compared with contrast-enhanced computed tomography (CT) of the abdomen and the pelvis in 33 patients. All these patients had undergone surgery. A comparison of results for tumor node metastasis classification between CTC, CT, and histopathology was performed.ResultsExploration of the entire colon was possible for 89.8% of the patients using CTC and 49.0% of the patients using colonoscopy. Bowel cleansing was assessed as worse with CTC. In the evaluation of tumor location and morphologic type, CTC was congruent with colonoscopy. Colonoscopy enabled approximate tumor size and volume to be evaluated for only 59.2% (29/49) and 30.6% (15/49) of patients, respectively, whereas CTC enabled evaluation of all 48 (100.0%) visualized tumors. Wall thickening, outer contour, and suspected infiltration of surrounding tissues and organs are impossible to determine with colonoscopy but can be determined with CTC. Using CTC, two additional tumors were found proximate to occlusive masses in endoscopically inaccessible regions.ConclusionComputed tomographic colonography is a useful method for diagnosing colorectal tumors. It allows the clinician to diagnose tumor, determine local tumor progression, and detect synchronous lesions in the large bowel including endoscopically inaccessible regions.

Computed tomographic colonography (CTC) has the potential to become an accepted technique for detecting of colorectal cancer. the aim of the study was to evaluate usefulness of CTC in preoperative evaluation of colorectal tumors and the regions of colon endoscopically unavailable. material and methods. A total of 49 patients with colorectal tumors identified at conventional colonoscopy were included. In all these patients CTC was performed and results were compared with colonoscopy. In addition in CTC infiltration of surrounding tissues, organs, lymph nodes and liver were assessed. Findings were compared with contrast-enhanced CT of abdomen. results. Colonoscopy was completed to the caecum in 24 (48.9%) patients. CTC failed only in one patient. CTC was congruent with colonoscopy in evaluation of tumor location and morphological type. In CTC two additional tumors were found proximately to occlusive masses, it is in endoscopically unavailable regions. Sensitivity and specificity of CTC comparing to CT in diagnosis of fat tissue infiltration and surrounding organs infiltration at the site of tumor were 95.5% / 50% and 100% / 86.9% respectively. Concordance of results in evaluation of lymph nodes was 93.9% while sensitivity and specificity for CTC was 84.6% and 100% respectively. Concordance of evaluation of liver metastases was 78.8%, while sensitivity and specificity for CTC was 61.5% and 90% respectively. Conclusions. CTC is a useful method in diagnostics of colorectal tumors. It allows to diagnose tumor, determine local tumor staging and detect synchronous lesions in endoscopically unavailable regions.