Computed tomographic colonography in preoperative evaluation of colorectal tumors: a prospective study

Abstract

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.

Clinical indications for computed tomographic colonography: European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guideline

“…A recent study including 286 CRC cases after failed colonoscopy showed CTC negative predictive values (NPVs) of 100% and 97% for synchronous cancer and advanced neoplasia, respectively, in a preoperative setting [ 58 ]. This is in line with a previous systematic review, showing equivalent sensitivity of colonoscopy and CTC for established cancer [ 22 ], and in line with findings from similar cohort studies [ 44 , 59 – 63 ].…”

Combined assessment using optical colonoscopy and computed tomographic colonography improves the determination of tumor location and invasion depth

“…CTC is an established method to screen for polyps and colorectal cancer . OC is regarded as the standard procedure for the detection of colorectal lesions and for the preoperative evaluation of patients with colorectal cancer.…”

“…Optical colonoscopy (OC) is used for screening and as part of the preoperative evaluation of patients with colorectal cancer . CT colonography (CTC) is a post‐processing imaging technique that can be used to screen for colorectal cancer and polyps and to preoperatively evaluate colorectal tumors . Previous reports have shown that the sensitivity of CTC compares favorably with that of OC for the detection of colorectal lesions .…”

Predictors of incomplete optical colonoscopy using computed tomographic colonography

“…It can also evaluate extraluminal pathology, which might contribute to a patient's symptom. [ 2 6 7 16 17 ]…”