CT colonography for synchronous colorectal lesions in patients with colorectal cancer: initial experience.
ABSTRACT To assess accuracy of CT colonography (CTC) in identifying synchronous lesions in patients with colorectal carcinoma.
This study included 174 consecutive patients undergoing CTC as part of staging or primary investigation where a colorectal cancer was diagnosed between 2004 and 2007. Prone unenhanced and portal phase enhanced supine series with air or CO(2) distension were acquired using 4- or 16-slice CT (Toshiba) and read by 2D +/- 3D formats. Synchronous lesions were classified according to American College of Radiology's (ACR) polyp classification. Segmental gold standard was flexible sigmoidoscopy/colonoscopy within 1 year and/or histology of colonic resection supplemented by follow-up. Nine patients without gold standard were excluded. Sensitivity, specificity and accuracy were calculated on a per polyp, per patient and per segment basis and discrepancies analysed.
Direct comparable data were available for 764/990 colonic segments from 165 patients. Of 41 (C2-C4) synchronous lesions on "gold standard", 33 were correctly identified on virtual colonoscopy (VC), overall per polyp sensitivity was 80.5%, with detection rates of 20/24 C3 (83.3%) and 3/3 C4 (100%) with per patient and per segment specificity of 95.4% and 99.2%, respectively.
CTC is an accurate technique to assess for significant synchronous lesions in patients with colorectal cancer and is applicable for total pre-operative colonic visualisation.
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ABSTRACT: In patients with colorectal cancer (CRC), accurate preoperative evaluation is essential for a correct therapeutic plan. Colonoscopy and intravenous contrast-enhanced computed tomography (CT) are currently recommended in the preoperative work-up for CRC. Preoperative colonoscopy has some limitations such as misdiagnosis of synchronous cancers in cases of incomplete exploration of the colon and inaccurate tumor localization. Intravenous contrast-enhanced CT successfully documents distant metastases although it sometimes enables unsatisfactory locoregional staging. Computed tomography colonography (CTC) is obtained after gas insufflation of the colon and offers a comprehensive preoperative evaluation in patients with CRC, including a definition of the segmental location of the tumor, presence of synchronous lesions or lack thereof, and fairly accurate locoregional staging. CTC has some limitations, including a lack of biopsy capability, suboptimal sensitivity for synchronous small polyps, and unsatisfactory nodal staging. Bearing in mind these limitations, CTC could be employed as a "one-stop-shop" examination for preoperative assessment in patients with CRC.World Journal of Gastroenterology 04/2014; 20(14):3795-3803. · 2.55 Impact Factor
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ABSTRACT: CT Colonography (CTC) is being increasingly used for the radiological evaluation of colorectal symptoms. Aim of this study was to assess the role of CTC in excluding a colorectal cancer (CRC) in older symptomatic patients. 1,359 CTC studies performed between March 2002 and December 2007 were analysed retrospectively. Gold standard was an endoscopic examination within 1 year and/or clinical, endoscopic and/or radiological follow-up until the time of data analysis. Patients not diagnosed as having a CRC on CTC were assumed as true-negatives if the gold standard was negative and did not feature on the regional cancer registry (at least 18 months post-CTC). Sensitivity, specificity, positive and negative predictive values were calculated for detection of colorectal cancer. After exclusions, 1,177 CTC studies were included. These were undertaken in 463 men and 714 women. Median age of patients undergoing CTC was 71 (range, 27-96) years. 59 invasive CRC were detected. Median follow-up was 34.5 (range 18-84) months. Three small colorectal cancers were missed. Sensitivity and negative predictive value for CRC were 94.9% (95% CI:84.9%-98.7%) and 99.7% (95% CI:99.1%-99.9%) respectively. CTC has a high sensitivity and negative predictive value in excluding a CRC in patients with colorectal symptoms.European Radiology 05/2011; 21(10):2029-38. · 4.34 Impact Factor
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ABSTRACT: In 2008, CT colonography was approved by the American Cancer Society as a technique for screening for colorectal cancer. This approval should be considered an important step in the recognition of the technique, which although still relatively new is already changing some diagnostic algorithms. This update about CT colonography reports the quality parameters necessary for a CT colonographic study to be diagnostic and reviews the technical innovations and colonic preparation for the study. We provide a brief review of the signs and close with a discussion of the current indications for and controversies about the technique.Radiología 06/2011; 53(4):315-25.