Computed tomographic colonography compared with colonoscopy in patients at increased risk for colorectal cancer (original) (raw)
Related papers
Gastroenterology, 2003
This study used a low lesion prevalence population reflective of the screening setting to estimate the sensitivity and specificity of computerized tomographic (CT) colonography for detection of colorectal polyps. Methods: This prospective, blinded study comprised 703 asymptomatic persons at higher-thanaverage risk for colorectal cancer who underwent CT colonography followed by same-day colonoscopy. Two of 3 experienced readers interpreted each CT colonography examination. Results: Overall lesion prevalence for adenomas >1 cm in diameter was 5%. Seventy percent of all lesions were proximal to the descending colon. With colonoscopy serving as the gold standard, CT colonography detected 34%, 32%, 73%, and 63% of the 59 polyps >1 cm for readers 1, 2, 3, and double-reading, respectively; and 35%, 29%, 57%, and 54% of the 94 polyps 5-9 mm for readers 1, 2, 3, and double-reading, respectively. Specificity for CT colonography ranged from 95% to 98% and 86% to 95% for >1 cm and 5-9-mm polyps, respectively. Interobserver variability was high for CT colonography with statistic values ranging from ؊0.67 to 0.89. Conclusions: In a low prevalence setting, polyp detection rates at CT colonography are well below those at colonoscopy. These rates are less than previous reports based largely on high lesion prevalence cohorts. High interobserver variability warrants further investigation but may be due to the low prevalence of polyps in this cohort and the high impact on total sensitivity of each missed polyp. Specificity, based on large numbers, is high and exhibits excellent agreement among observers.
CT Colonography of Colorectal Polyps: A Metaanalysis
American Journal of Roentgenology, 2003
CT Colonography of Colorectal Polyps: A Metaanalysis OBJECTIVE. For proper evaluation of the accuracy of CT colonography, prospective multiinstitutional trials would be ideal. Until these trials are available, data can be collectively analyzed. The purpose of this study is to use metaanalysis to assess the reported accuracy of CT colonography compared with conventional colonoscopy for detecting colorectal polyps. MATERIALS AND METHODS. Articles comparing CT colonography and conventional colonoscopy were identified, and a standardized form was used to extract relevant study data. Fisher's exact test and the Mantel-Haenszel test were used for pooling of data. A 95% confidence interval (CI) was selected to determine sensitivity and specificity, and the Kruskal-Wallis exact test was used to identify trends relating to polyp size. Meta-analysis methods were used to test strength of results. Comparisons were made for the percentage of polyps detected grouped by size (≥ 10 mm, 6-9 mm, ≤ 5 mm) and the percentage of patients identified who had polyps of the same size. RESULTS. Fourteen studies fulfilled all the study inclusion criteria and gave a total of 1,324 patients and 1,411 polyps. The pooled per-patient sensitivity for polyps 10 mm or larger was (sensitivity [95% CI]) 0.88 (0.84-0.93), for polyps 6-9 mm it was 0.84 (0.80-0.89), and for polyps 5 mm or smaller it was 0.65 (0.57-0.73). The pooled per-polyp sensitivity for polyps 10 mm or larger was 0.81 (0.76-0.85), for polyps 6-9 mm it was 0.62 (0.58-0.67), and for polyps 5 mm or smaller it was 0.43 (0.39-0.47). Sensitivity for detection of polyps increased as the polyp size increased (p < 0.00005). The pooled overall specificity for detection of polyps larger than 10 mm was 0.95 (0.94-0.97). CONCLUSION. The specificity and sensitivity of CT colonography are high for polyps larger than 10 mm. olorectal cancer is the second leading cause of cancer mortality in the United States. Most carcinomas arise from preexisting adenomas [1]. Conventional endoscopic colonoscopy is currently the modality of choice for colorectal cancer screening [2]. CT colonography (CTC) was first described in 1994 [3] as a noninvasive rapid imaging method to investigate the colon and rectum. Since then, several studies have showed its role as a minimally invasive test for detection of colorectal cancer and polyps. Early results are encouraging and several single-institution studies have been published comparing CT colonography with conventional colonoscopy (CC). CT colonography is currently performed in some centers as a screening test for colorectal polyps and cancers, and large prospective multicenter trials assessing CT colonography as a population-screening tool are under way [4]. The purpose of this study is to use metaanalysis to assess the reported accuracy of CT colonography compared to conventional colonoscopy for detecting colorectal polyps. Materials and Methods Literature Search A comprehensive literature search of Englishlanguage studies was performed using the Pub Med and Medline databases and search algorithms, with the keywords "CT colonography," "CT colonoscopy," "virtual colonoscopy," and "CT pneumocolon." Searches included peer-reviewed studies that were published between 1994 and July 2002. Review articles, letters, comments, and articles without original data and conference abstracts were excluded.
Gastroenterología y Hepatología, 2007
OBJECTIVE: To determine the diagnostic accuracy of computed tomography colonography (CTC) compared with conventional colonoscopy (CC). METHODS: Patients with an indication of CC were included. Fifty patients underwent CTC using multidetector CT before diagnostic colonoscopy was performed by an expert colonoscopist. Diagnostic accuracy was assessed individually both for each polyp and for each patient. RESULTS: Fifty patients were included and 40 polyps were analyzed. The by-polyp sensitivity of CTC was 15% for polyps 5 mm or less, 75% for polyps 5-10 mm and 75% for polyps 10 mm or larger. By-patient specificity was 6% for polyps 5 mm or less, 75% for polyps 5-10 mm and 80% for polyps 10 mm or larger. The specificity of CTC was 94%. CTC was preferred over CC by 90% of the patients. The mean colonoscopy examination time was 30 minutes for CC and 35 minutes for CTC (p < 0.05). CONCLUSIONS: The sensitivity of CTC is moderate in detecting polyps larger than 10 mm, low in detecting 5-10 mm polyps and very low in detecting those less than 5 mm. The overall specificity of the procedure was 94%. Procedure time was lower with CC than with CTC but the latter was better tolerated by most patients.
American Journal of Roentgenology, 2008
C olorectal cancer (CRC) is a major cause of morbidity and mortality in Western societies, and its therapeutic costs are a substantial economic burden [1]. According to the widely accepted adenoma-carcinoma sequence, most cancers develop from a small subset of benign adenomatous polyps over a long period of time [2]. Thus, CRC screening of average-risk adults based on polyp detection and cancer prevention has been universally accepted [3]. Among the available screening options, 3D CT colonography (CTC) is an emerging test that has shown good performance for the detection of advanced neoplasia [4-7] and offers the potential for selectively and noninvasively identifying those patients who would clearly benefi t from therapeutic colonoscopy [8, 9]. Instituting a polyp size threshold for colonoscopic referral at screening CTC is somewhat
Middle East Journal of Digestive Diseases, 2021
BACKGROUND The incidence of colorectal cancer is increasing in the northeast of Iran. Colorectal polyps are among the proposed risk factors noted, especially in the elder population. This study was designed to study the diagnosed cases of intestinal polyps detected from 2011 to 2016 in the northeast of Iran. METHODS The population consisted of symptomatic candidates referred to the colonoscopy center in Gorgan city. Based on the available colonoscopy and pathology reports, 1706 cases were enrolled after the exclusion of cases without sufficient data. RESULTS Among 1709 (55.5% males and 44.5% females) cases, 1405 cases with 1912 polyps were detected. Among them, 345 (25%) aged less than 50 years. Tubular adenoma (N = 826, 43.2%) and hyperplastic polyps (N = 519, 27.1%) were the top two histological findings. Out of 1405 patients with polyps, 660 (39.6%) polyps were detected in proximal colon (15.6% in proximal and 24% in both proximal and distal). Malignancies were detected in 13.2% ...