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Purpose: Computed tomographic colonography (CTC) is a non-invasive screening test for colorectal cancer (CRC) with high sensitivity and low risk of complications. We used a nationally representative sample of screening-eligible adults to examine trends in and factors associated with CTC use., Methods: We examined CTC use among 58,058 adults in the National Health Interview Survey in 2010, 2015, 2018, 2019, and 2021. For each survey year, we estimated CTC use by sociodemographic and health factors. We used multivariable logistic regression to identify factors associated with CTC use., Results: A total of 1.7 % adults reported receiving CTC across all survey years. CTC use was similar in 2010 (1.3 %), 2015 (0.8 %), 2018 (1.4 %), and 2019 (1.4 %) but increased in 2021 (3.5 %, p < 0.05). In multivariable analysis, survey year 2021 [vs. 2010, odds ratio (OR) 2.51, 95 % confidence interval (CI) 1.83-3.43], Hispanic (OR 1.73, 95 % CI 1.34-2.23), non-Hispanic Black (OR 2.07, 95 % CI 1.67-2.57), and household income <200 % federal poverty level (vs. >400 %, OR 1.25, 95 % CI 1.01-1.57) was associated with CTC use. Further, adults with a history of diabetes (OR 1.20, 95 % CI 1.01-1.45), chronic obstructive pulmonary disease (OR 1.58, 95 % CI 1.25-1.99), cancer (OR 1.29, 95 % CI 1.05-1.58), or past-year hospital admissions (OR 1.44, 95 % CI 1.18-1.78) were more likely to receive CTC., Conclusion: CTC use remained low from 2010 to 2019 but increased in 2021. CTC use was more frequent among adults with chronic health conditions, minorities, and adults with lower income, and may help reduce disparities in CRC screening., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: PHL reports financial support was provided by The University of Texas Southwestern Medical Center. AGS has served as a consultant or on advisory boards for Exact Sciences, Universal Dx, and Roche. CB reports research funding from Bracco Diagnostics. AA has no conflicts to disclose. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Colorectal cancer is the second leading cause of cancer-related mortality in adults in the United States. Despite compelling evidence of improved outcomes in colorectal cancer, screening rates are not optimal. This study aimed to characterize colorectal cancer screening trends over the last two decades and assess the impact of various screening modalities on overall colorectal cancer screening rates. Using National Health Interview Survey data from 2005 to 2021, we examined colorectal cancer screening [colonoscopy, multitarget stool DNA (mt-sDNA), fecal occult blood test (FOBT)/fecal immunochemical test, sigmoidoscopy, CT colonography] rates among adults ages 50-75 years (n = 85,571). A pseudo-time-series cross-sectional (pseudo-TSCS) analysis was conducted including a random effects generalized least squares regression model to estimate the relative impact of each modality on changes in colorectal cancer screening rates. Among 50 to 75 year olds, the estimated colorectal cancer screening rate increased from 47.7% in 2005 to 69.9% in 2021, with the largest increase between 2005 and 2010 (47.7%-60.7%). Rates subsequently plateaued until 2015 but increased from 63.5% in 2015 to 69.9% in 2018. This was primarily driven by the increased use of mt-sDNA (2.5% in 2018 to 6.6% in 2021). Pseudo-TSCS analysis results showed that mt-sDNA contributed substantially to the increase in overall screening rates (77.3%; P < 0.0001) between 2018 and 2021. While colorectal cancer screening rates increased from 2005 to 2021, they remain below the 80% goal. The introduction of mt-sDNA, a noninvasive screening test may have improved overall rates. Sustained efforts are required to further increase screening rates to improve patient outcomes and offering a range of screening options is likely to contribute to achieving this goal., Prevention Relevance: This retrospective study highlights the importance of convenient stool-based colorectal cancer screening options to achieve the national goal of 80% for overall colorectal cancer screening rates. Empowering screening-eligible individuals with a choice for their colorectal cancer screening tests is imperative., (©2024 The Authors; Published by the American Association for Cancer Research.)

Background: Obtaining the right image dataset for the medical image research systematically is a tedious task. Anatomy segmentation is the key step before extracting the radiomic features from these images., Objective: The purpose of the study was to segment the 3D colon from CT images and to measure the smaller polyps using image processing techniques. This require huge number of samples for statistical analysis. Our objective was to systematically classify and arrange the dataset based on the parameters of interest so that the empirical testing becomes easier in medical image research., Materials and Methods: This paper discusses a systematic approach of data collection and analysis before using it for empirical testing. In this research the image were considered from National Cancer Institute (NCI). TCIA from NCI has a vast collection of diagnostic quality images for the research community. These datasets were classified before empirical testing of the research objectives. The images in the TCIA collection were acquired as per the standard protocol defined by the American College of Radiology. Patients in the age group of 50-80 years were involved in various clinical trials (multicenter). The dataset collection has more than 10 billion of DICOM images of various anatomies. In this study, the number of samples considered for empirical testing was 300 (n) acquired from both supine and prone positions. The datasets were classified based on the parameters of interest. The classified dataset makes the dataset selection easier during empirical testing. The images were validated for the data completeness as per the DICOM standard of the 2020b version. A case study of CT Colonography dataset is discussed., Conclusion: With this systematic approach of data collection and classification, analysis will be become more easier during empirical testing., .

Aim: To review the indications for computed tomography colonography (CTC) performed on patients referred via the 2-week wait colorectal pathway (2WWCP)., Materials and Methods: A retrospective study was performed on all patients referred through the 2WWCP between October 2018 and September 2019. The referrals were audited against the National Institute for Health and Care Excellence (NICE) NG12/DG30 guidelines for referral to the 2WWCP, and against the Royal College of Radiologists (RCR) 2017 guidelines for CTC., Results: Over the study period, there were 1,707 2WWCP referrals, and 362 (21.2%) of these patients underwent CTC. The median age was 66 years, and 55% were female. Forty-six patients did not meet the NICE NG12/DG30 guidelines for referral to the 2WWCP, and a further 268, although meeting the NICE guidelines, did not meet the RCR 2017 guidelines for CTC. In total, only 13% of CTCs performed complied with both guidelines., Conclusion: This audit demonstrated a significant opportunity to reallocate CTC resources in the recovery stage of the COVID-19 pandemic. To improve outcomes for colorectal cancer (CRC) in the UK, establishing a selective straight-to-test CTC 2WWCP should be considered. Documented consent detailing the risks and benefits of CTC versus colonoscopy should take place in order to assist the patient in making an informed choice., (Copyright © 2020 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

CT colonography for colorectal cancer screening has been proved to be effective and cost-saving. CT colonography uses minimally invasive evaluation of colorectum and has better patient acceptance, which appears to be a promising screening modality to improve low colorectal cancer screening rate. This study investigated the utilization patterns of CT colonography and factors associated with its use among U.S. adult population. This retrospective cross-sectional study analyzed the National Health Interview Survey 2015 and 2018. U.S. adults ages 45 or older without a history of colorectal cancer were included. Survey design-adjusted Wald F tests were used to compare the utilization of CT colonography during the study period. Multivariable logistic regression was used to identify the predictors of CT colonography among individual socioeconomic and health-related characteristics. The study sample included 34,768 individuals representing 129,430,319 U.S. adult population ages 45 or older. The overall utilization of CT colonography increased from 0.79% in 2015 to 1.33% in 2018 ( P < 0.001). 54.5% study participants reported being up-to-date on recommended colorectal cancer screening; of those, 1.8% used CT colonography. Compared with individuals ages 65+, those ages 45-49 years were 2.08 times (OR, 2.08, 95% confidence interval, 1.01-4.35) more likely to use CT colonography. Socioeconomically disadvantaged characteristics (e.g., racial/ethnic minority, low income, publicly funded insurance) were associated with a greater likelihood of CT colonography. This study demonstrated an increasing trend in utilization of CT colonography for colorectal cancer screening in U.S. adults. Younger individuals, racial/ethnic minorities, or those with lower income appear to have a higher CT colonography utilization. PREVENTION RELEVANCE: Although computed tomographic (CT) colonography has been proved to be cost-effective and have better patient acceptance, its overall utilization for colorectal cancer (CRC) screening is low (<1.4%) among US adults aged 45+ in 2018. More efforts are needed to implement strategies to increase CT colonography for effective CRC prevention., (©2020 American Association for Cancer Research.)

Aim: To evaluate the clinical and cost implications of using computed tomography colonography (CTC) compared to optical colonoscopy (OC) as the initial colonic investigation in patients with low-to-intermediate risk of colorectal cancer (CRC)., Materials and Methods: A non-randomised, prospective single-centre study recruited 180 participants to compare the cost implications of two clinical pathways used in the diagnosis of low-to-intermediate risk of CRC that differ in the initial diagnostic test, either CTC or OC. Costs were compared using generalised linear models (GLM) and combined with quality-adjusted life years (QALYs, based on the EQ-5D-5L) to estimate cost-effectiveness at 6 months post-recruitment. Secondary outcomes assessed access to care and patient satisfaction., Results: Mean (SD, n) cost at 6 months post-recruitment per participant was £991 (£316, n=105) for the OC group and £645 (£607, n=68) for the CTC group, leading to an estimated cost difference of -£370 (95% CI: -£554, -£185, p<0.001). Assuming a £20,000 willingness-to-pay per QALY threshold, there was a 91.4% probability of CTC being cost-effective at month 6. The utilisation of CTC led to improved access to care, with a shorter mean time from referral from primary care to results (6.3 days difference, p=0.005). No differences in patient satisfaction were detected between both groups., Conclusion: The utilisation of CTC as the first-line investigation for patients with low-to-intermediate risk of CRC has the potential to release OC capacity, of pivotal importance for patients more likely to benefit from an invasive diagnostic approach., Competing Interests: Conflict of interest The authors declare no conflict of interest., (Copyright © 2020 The Royal College of Radiologists. All rights reserved.)

Background: Guidelines suggest computed tomography colonography (CTC) following incomplete optical colonoscopy (OC). Colon capsule endoscopies (CCE) have been suggested as an alternative, although completion rates have been unsatisfactory. Introduction of artificial intelligence (AI)-based localization algorithms of the camera capsules may enable identification of incomplete CCE investigations overlapping with incomplete OCs., Objective: The study aims to investigate relative sensitivity of CCE compared with CTC following incomplete OC, investigate the completion rate when combining results from the incomplete OC and CCE, and develop a forward-tracking algorithm ensuring a safe completeness of combined investigations., Methods: In this prospective paired study, patients with indication for CTC following incomplete OC were included for CCE and CTC. Location of CCE abortion and OC abortion were registered to identify complete combined investigations. AI-based algorithm for localization of capsules were developed reconstructing the passage of the colon., Results: In 237 individuals with CTC indication; 105 were included, of which 97 underwent both a CCE and CTC. CCE was complete in 66 (68%). Including CCEs which reached most oral point of incomplete OC, 73 (75%) had complete colonic investigations; 78 (80%) had conclusive investigations. Relative sensitivity of CCE compared with CTC was 2.67 (95% confidence interval (CI) 1.76;4.04) for polyps >5 mm and 1.91 (95% CI 1.18;3.09) for polyps >9 mm. An AI-based algorithm was developed., Conclusion: Sensitivity of CCE following incomplete OC was superior to CTC. Introducing and improving algorithm-based localization of capsule abortion may increase identification of overall complete investigation rates following incomplete OC.ClinicalTrials.gov identifier: NCT02826993.

Many systematic reviews and meta-analyses concern the effect of a healthcare intervention on a binary outcome i.e . occurrence (or not) of a particular event. Usually, the overall effect, pooled across all studies included in the meta-analysis, is summarised using the odds ratio (OR) or the relative risk (RR). Under most circumstances, it is obvious how to identify what should be considered as the event of interest-for example, death or a clinically important side-effect. However, on occasion it may not be clear in which "direction" the event should be specified-such as attendance ( vs non-attendance) at cancer screening. Usually, this choice is not critical to the overall conclusion of the meta-analysis, but occasionally it can lead to differences in how the included studies are pooled, ultimately affecting the overall meta-analytic result, particularly when using RRs rather than ORs. In this commentary, we will explain this phenomenon in more detail using examples from the literature, and explore how analysts and readers can avoid some potential pitfalls.

Objective: To compare the participation rate between CT colonography (CTC) and colonoscopy in screening population in randomized controlled trials (RCTs)., Methods: A search was performed using the PubMed, Web of Science, and Cochrane databases. RCTs that included screening populations and reported participation number were assessed. Cochrane risk of bias tool was used to assess the bias and quality. Risk ratio (RR) was used to present the results. The non-participation rate was analyzed to verify the results of participation rate., Results: Five of 760 studies, with a total of 15,974 invitees, were included. The participation rate was higher at CTC (28.8%) than colonoscopy (20.8%), although the difference did not reach statistical significance (RR = 1.26; p = 0.070; I 2 = 90.3%). The non-participation rate at CTC was significantly lower than colonoscopy (RR = 0.92; p = 0.012; I 2 = 86.7%). Subgroup analysis suggested both the participation and non-participation rate were with significant difference between reduced/no cathartic preparation CTC and colonoscopy. Cumulative meta-analysis showed both the participation rate and non-participation rate exhibited a trend over time and sample size., Conclusion: The participation rate was higher at CTC than colonoscopy, although the difference did not reach statistical significance. But the non-participation rate was with statistical difference. Screening population seemed more likely to participate the reduced/no cathartic preparation CTC. Statistical evidence was provided for more large RCTs are needed in the future., Advances in Knowledge: The screening populations seem more likely to participate in the CTC, especially the reduced/no cathartic preparation CTC. The statistical evidence was provided for more large RCTs are needed in the future.

Background/aims: Non-polypoid colon lesions compared with polypoid lesions has a high malignant potential. The diagnostic performance of colon capsule endoscopy (CCE) and CT colonography (CTC) for large colorectal non-polypoid tumours, that is, laterally spreading tumours is still unclear. The aim of this study is to evaluate the performance of CCE and CTC for the diagnosis of large non-polypoid tumours., Methods: Thirty patients referred for endoscopic submucosal dissection of non-polypoid tumours measuring ≥20 mm were enrolled. Patients first underwent CCE, then colonoscopy (without resection) and CTC on the same day. An experienced gastroenterologist in a third hospital evaluated the CCE and recorded the location, size and morphology of all lesions detected, blinded to the colonoscopic findings. An experienced radiologist read the CTC under the same conditions. Colonoscopic findings were defined as the reference., Results: A total of 30 lesions (T1 cancer: 3, Tis cancer: 7, adenoma: 14, sessile serrated adenoma/polyp: 6) in 27 patients were observed for evaluation. The capsule excretion rate within 8 h was 85% (23/27), and all capsules went beyond the target lesions. Non-polypoid tumours tend to be depicted as polypoid on CCE. Per patient sensitivities were 0.89 (24/27) by CCE and 0.70 (19/27) by CTC (p = 0.0253, McNemar), and per lesion sensitivities were 0.87 (26/30) and 0.67 (20/30) respectively (p = 0.0143). Most lesions missed by both modalities were located in the proximal colon., Conclusion: Eighty-seven per cent of non-polypoid tumours were detected by CCE, and the sensitivity using CCE was higher than that obtained using CTC (UMIN0000014772)., (© 2019 S. Karger AG, Basel.)

Aim: The purpose of the present study was to evaluate the accuracy of computed tomography colonography (CTC) in the preoperative localization and TN staging of colon cancer. CTC can be an effective technique for preoperative evaluation of colon cancer and could facilitate the selection of high-risk patients who may benefit from neoadjuvant chemotherapy., Method: This was a prospective observational study conducted at a single tertiary-care centre. It involved 217 patients (225 tumours) who had colon cancer and underwent preoperative CTC and elective colectomy. The radiologist determined the TNM stage using postprocessing software with multiplanar images and virtual colonoscopy. The following criteria were analysed for every colon tumour: location, size and signs of direct colon wall invasion. The histopathological findings of the surgical colectomy specimens served as the reference standard for local staging., Results: CTC detected all tumours and achieved an exact location in 208 cases (92.4%). CTC findings changed the surgical plan in 31 patients (14.3%) following colonoscopy. The accuracy in differentiating T3/T4 vs T1/T2 tumours was 87.1%, with a sensitivity and specificity of 88.5% and 84.1%, respectively (kappa = 0.71). For high-risk tumours (T3 ≥ 5 mm and T4), CTC showed an accuracy, sensitivity and specificity of 82.7%, 86% and 80%, respectively (kappa = 0.65). The accuracy of N-stage evaluation was 69.3%, the sensitivity 74% and the specificity 67.1% (kappa = 0.37)., Conclusion: CTC provides accurate information for the assessment of tumour localization and T staging, allowing better surgical planning and also allows the selection of locally advanced tumours that may benefit from new treatments such as neoadjuvant chemotherapy., (Colorectal Disease © 2019 The Association of Coloproctology of Great Britain and Ireland.)

Background: Surgical resection is the recommended procedure for colorectal cancer (CRC), but majority of the patients were diagnosed with advanced or metastatic CRC. Currently, there were inconsistent results about the diagnostic value of magnetic resonance colonography (MRC) and computed tomography colonography (CTC) in early CRC diagnosis. Our study conducted this meta-analysis to investigate the diagnostic value of MRC and CTC for CRC surveillance., Methods: A comprehensive literature search was conducted in PubMed, Embase, and the Cochrane library to select relevant studies. The summary sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the area under the receiver operating characteristic curves (AUC) were calculated to evaluate the diagnostic value of MRC and CTC, respectively., Result: Twenty-five studies including 2985 individuals were selected in the final analysis. Eight studies evaluated the diagnostic value of MRC, and 17 studies assessed CTC. The summary sensitivity, specificity, PLR, NLR, DOR, and AUC in MRC for early detection of CRC were 0.98 (95% confidence interval, CI: 0.80-1.00), 0.94 (95% CI: 0.85-0.97), 15.48 (95% CI: 6.30-38.04), 0.02 (95% CI: 0.00-0.25), 115.09 (95% CI: 15.37-862.01), and 0.98 (95% CI: 0.97-0.99), respectively. In addition, the sensitivity, specificity, PLR, NLR, DOR, and AUC of CTC for diagnosing CRC were 0.97 (95% CI: 0.88-0.99), 0.99 (95% CI: 0.99-1.00), 154.11 (95% CI: 67.81-350.22), 0.03 (95% CI: 0.01-0.13), 642.51 (95% CI: 145.05-2846.02), and 1.00 (95% CI: 0.99-1.00). No significant differences were found between MRC and CTC for DOR in all the subsets., Conclusion: The findings of meta-analysis indicated that MRC and CTC have higher diagnostic values for early CRC diagnosis. However, the DOR for diagnosing CRC between MRC and CTC showed no significance.

Purpose To compare the cost-effectiveness of computed tomographic (CT) colonography and colonoscopy screening by using data on unit costs and participation rates from a randomized controlled screening trial in a dedicated screening setting. Materials and Methods Observed participation rates and screening costs from the Colonoscopy or Colonography for Screening, or COCOS, trial were used in a microsimulation model to estimate costs and quality-adjusted life-years (QALYs) gained with colonoscopy and CT colonography screening. For both tests, the authors determined optimal age range and screening interval combinations assuming a 100% participation rate. Assuming observed participation for these combinations, the cost-effectiveness of both tests was compared. Extracolonic findings were not included because long-term follow-up data are lacking. Results The participation rates for colonoscopy and CT colonography were 21.5% (1276 of 5924 invitees) and 33.6% (982 of 2920 invitees), respectively. Colonoscopy was more cost-effective in the screening strategies with one or two lifetime screenings, whereas CT colonography was more cost-effective in strategies with more lifetime screenings. CT colonography was the preferred test for willingness-to-pay-thresholds of €3200 per QALY gained and higher, which is lower than the Dutch willingness-to-pay threshold of €20 000. With equal participation, colonoscopy was the preferred test independent of willingness-to-pay thresholds. The findings were robust for most of the sensitivity analyses, except with regard to relative screening costs and subsequent participation. Conclusion Because of the higher participation rates, CT colonography screening for colorectal cancer is more cost-effective than colonoscopy screening. The implementation of CT colonography screening requires previous satisfactory resolution to the question as to how best to deal with extracolonic findings. © RSNA, 2018 Online supplemental material is available for this article.

Background: Advanced colorectal cancers were associated with poor prognosis, and early diagnosis was important for high-risk patients. Colonography is commonly used for diagnosing colorectal cancer. However, a few studies reported the diagnostic value of magnetic resonance colonography (MRC) versus computed tomography colonography (CTC). This study aimed to compare the diagnostic value of MRC versus CTC for colorectal cancer., Methods: Twenty-three studies on the diagnosis of colorectal cancer using MRC or CTC were obtained from PubMed, Embase, and the Cochrane Library databases until July 2017. The ratios of sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and receiver operating characteristic (ROC) curve were calculated to compare the diagnostic value of MRC versus CTC., Results: The summary sensitivity, specificity, PLR, NLR, and area under the ROC for MRC were 0.97 (0.81-1.00), 0.92 (0.80-0.97), 11.71 (4.46-30.73), 0.03 (0.00-0.24), and 0.98 (0.97-0.99), respectively, for diagnosing colorectal cancer. The pooled estimates for CTC in diagnosing colorectal cancer were as follows: sensitivity, 0.96 (0.90-0.98); specificity, 1.00 (0.99-1.00); PLR, 197.32 (73.21-531.85); NLR, 0.04 (0.02-0.11); and area under the ROC, 1.00 (0.99-1.00). No significant differences were found between MRC and CTC for sensitivity, specificity, and NLR. MRC was associated with lower PLR and area under the ROC for diagnosing colorectal cancer compared with CTC., Conclusion: This study demonstrated MRC and CTC as potential diagnostic approaches for colorectal cancer. CTC had a higher diagnostic value of PLR and area under the ROC for colorectal cancer.

The aim of this study was to evaluate the participation and yield of the faecal immunochemical test (FIT) in nonattendees for computed tomography colonography (CTC) or optical colonoscopy (OC) screening, in the setting of a randomized trial. In the SAVE trial, 16087 individuals were randomly assigned and invited to one of four interventions for colorectal cancer screening: (i) biennial FIT for three rounds; (ii) reduced-preparation CTC; (iii) full-preparation CTC; and (iv) OC. Nonattendees of reduced-preparation CTC, full-preparation CTC and OC groups were invited to FIT. Here, we analysed the participation rate and the detection rate for cancer or advanced adenoma (advanced neoplasia) of FIT among nonattendees for reduced-preparation CTC, full-preparation CTC and OC. Nonattendees were 1721 of 2395 (71.9%) eligible invitees in the reduced-preparation CTC group, 1818 of 2430 (74.8%) in the full-preparation CTC group and 883 of 1036 (85.2%) in the OC group. Participation rates for FIT were 20.2% (347/1721) in nonattendees for reduced-preparation CTC, 21.4% (389/1818) in nonattendees for full-preparation CTC and 25.8% (228/883) in nonattendees for OC. Differences between both CTC groups and the OC group were statistically significant (P≤0.01), whereas the difference between reduced-preparation and full-preparation CTC groups was not statistically significant (P=0.38). The detection rate of FIT was not statistically significantly different among nonattendees for reduced-preparation CTC (0.9%; 3/347), nonattendees for full-preparation CTC (1.8%; 7/389) and nonattendees for OC (1.3%; 3/228) (P>0.05). Offering FIT to nonattendees for CTC or OC increases the overall participation in colorectal cancer screening and enables the detection of additional advanced neoplasia.

Purpose To compare overall colorectal cancer (CRC) screening rates for patients who were eligible and due for CRC screening and who were with and without insurance coverage for computed tomographic (CT) colonography for CRC screening. Materials and Methods The institutional review board approved this retrospective cohort study, with a waiver of consent. This study used longitudinal electronic health record data from 2005 through 2010 for patients managed by one of the largest multispecialty physician groups in the United States. It included 33 177 patients under age 65 who were eligible and due for CRC screening and managed by the participating health system. Stratified Cox regression models provided propensity-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the relationship between CT colonography coverage and CRC screening. Results After adjustment, patients who had insurance coverage for CT colonography and were due for CRC screening had a 48% greater likelihood of being screened for CRC by any method compared with those without coverage who were due for CRC screening (HR, 1.48; 95% CI: 1.41, 1.55). Similarly, patients with CT colonography coverage had a greater likelihood of being screened with CT colonography (HR, 8.35; 95% CI: 7.11, 9.82) and with colonoscopy (HR, 1.38; 95% CI: 1.31, 1.45) but not with fecal occult blood test (HR, 1.00; 95% CI: 0.91, 1.10) than those without such insurance coverage. Conclusion Insurance coverage of CT colonography for CRC screening was associated with a greater likelihood of a patient being screened and a greater likelihood of being screened with a test that helps both to detect cancer and prevent cancer from developing (CT colonography or colonoscopy). © RSNA, 2017.

Objective: We assessed the initial clinical performance and third-party reimbursement rates of supplementary computer-aided detection (CAD) at CT colonography (CTC) for detecting colorectal polyps 6 mm or larger in routine clinical practice., Materials and Methods: We retrospectively assessed the prospective clinical performance of a U.S. Food and Drug Administration-approved CAD system in second-reader mode in 347 consecutive adults (mean age, 57.6 years; 205 women, 142 men) undergoing CTC evaluation over a 5-month period. The reference standard consisted of the prospective interpretation by experienced CTC radiologists combined with subsequent optical colonoscopy (OC), if performed. We also assessed third-party reimbursement for CAD for studies performed over an 18-month period., Results: In all, 69 patients (mean [± SD] age, 59.0 ± 7.7 years; 32 men, 37 women) had 129 polyps ≥ 6 mm. Per-patient CAD sensitivity was 91.3% (63 of 69). Per-polyp CAD-alone sensitivity was 88.4% (114 of 129), including 88.3% (83 of 94) for 6- to 9-mm polyps and 88.6% (31 of 35) for polyps 10 mm or larger. On retrospective review, three additional polyps 6 mm or larger were seen at OC and marked by CAD but dismissed as CAD false-positives at CTC. The mean number of false-positive CAD marks was 4.4 ± 3.1 per series. Of 1225 CTC cases reviewed for reimbursement, 31.0% of the total charges for CAD interpretation had been recovered from a variety of third-party payers., Conclusion: In our routine clinical practice, CAD showed good sensitivity for detecting colorectal polyps 6 mm or larger, with an acceptable number of false-positive marks. Importantly, CAD is already being reimbursed by some third-party payers in our clinical CTC practice.

Purpose: To examine factors influencing primary care provider (PCP) adoption of CT colonography (CTC) for colorectal cancer (CRC) screening., Materials and Methods: We performed a retrospective cohort study linking electronic health record (EHR) data with PCP survey data. Patients were eligible for inclusion if they were not up-to-date with CRC screening and if they had CTC insurance coverage in the year prior to survey administration. PCPs were included if they had at least one eligible patient in their panel and completed the survey (final sample N = 95 PCPs; N = 6245 patients). Survey data included perceptions of CRC screening by any method, as well as CTC specifically. Multivariate logistic regression estimated odds ratios and 95% confidence intervals for PCP and clinic predictors of CRC screening by any method and screening with CTC., Results: Substantial variation in CTC use was seen among PCPs and clinics (range 0-16% of CRC screening). Predictors of higher CTC use were PCP perceptions that CTC is effective in reducing CRC mortality, higher number of perceived advantages to screening with CTC, and Internal Medicine specialty. Factors not associated with CTC use were PCP perceptions of less organizational capacity to meet demand for colonoscopy, number of perceived disadvantages to screening with CTC, PCP age and gender, and clinic factors., Conclusion: Significant variation in PCP adoption of CTC exists. PCP perceptions of CTC and specialty practice were related to CTC adoption. Strategies to increase PCP adoption of CTC for CRC screening should include emphasis on the effectiveness and advantages of CTC.

Objective: The purposes of this study were to compare rates of lesion detection at CT colonographic (CTC) screening of adults without symptoms who had and who did not have a family history of colorectal cancer according to American Cancer Society guidelines and to consider the clinical implications., Materials and Methods: Over 134 months, consecutively registered CTC cohorts of adults without symptoms who had (n = 156; 88 [56.4%] women; 68 [43.6%] men; mean age, 56.3 years) and who did not have (n = 8857; 4757 [53.7%] women; 4100 [46.3%] men; mean age, 56.6 years) an American Cancer Society-defined family history of colorectal cancer (first-degree relative with diagnosis before age 60 years or two first-degree relatives with diagnosis at any age) were compared for relevant colorectal findings., Results: For the family history versus no family history cohorts, the frequency of all nondiminutive polyps (≥ 6 mm) reported at CTC was 23.7% versus 15.5% (p = 0.007); small polyps (6-9 mm), 13.5% versus 9.1% (p = 0.068); and large polyps (≥ 10 mm), 10.2% versus 6.5% (p = 0.068). The rate of referral for colonoscopy was greater for the family history cohort (16.0% vs 10.5%; p = 0.035). However, the frequencies of proven advanced adenoma (4.5% vs 3.2%; p = 0.357), nonadvanced adenoma (5.1% vs 2.6%; p = 0.070), and cancer (0.0% vs 0.4%; p = 0.999) were not significantly increased. The difference in positive rates between the two cohorts (11.5% vs 4.3%; p < 0.001) was primarily due to nonneoplastic findings of no colorectal cancer relevance, such as small hyperplastic polyps, diverticular disease, and false-positive CTC findings., Conclusion: Although the overall CTC-positive and colonoscopy referral rates were higher in the family history cohort, the clinically relevant frequencies of advanced neoplasia and cancer were not sufficiently increased to preclude CTC screening. These findings support the use of CTC as a front-line screening option in adults with a family history of colorectal cancer.

Objective: Planning imaging performed during CT-guided procedures may occasionally contain important incidental findings. The purpose of this study was to identify and characterize by clinical relevance the extraspinal findings detected on planning imaging for CT-guided lumbar transforaminal epidural steroid injections (TFESIs)., Materials and Methods: Four radiologists retrospectively evaluated the planning scout views and CT studies for 488 consecutive CT-guided lumbar TFESIs performed in 400 patients over a 1-year period. Incidental extraspinal findings were identified and used to characterize patients by the need for follow-up using the CT Colonography Reporting and Data System (C-RADS), a classification scheme originally developed to characterize incidental findings on CT colonography. Patients with C-RADS E4 findings have potentially important findings that should be communicated to the referring physician; patients with C-RADS E3 findings have findings that are likely unimportant, but workup may be indicated. All previously unknown C-RADS E3 and E4 findings discovered in the course of this research were reported to referring physicians for appropriate patient follow-up., Results: Ten of 400 (2.5%) patients were classified as C-RADS E4; the most common C-RADS E4 finding was vascular aneurysm or stenosis (4/400, 1.0%). Thirteen of 400 (3.3%) patients were classified as C-RADS E3; the most common C-RADS E3 finding was hepatomegaly (4/400, 1.0%). Of 22 patients with C-RADS E3 and E4 findings unknown to clinicians, the finding for only one (4.5%) was communicated to clinicians at the time of the procedure., Conclusion: Clinically important incidental extraspinal findings were identified in 5.8% of patients on the planning imaging performed for CT-guided lumbar TFESIs. Communication of clinically important findings was poor (4.5%).

Objective: We wanted to assess the diagnostic value of computed tomographic colonography (CTC) in recognizing bowel endometriosis in comparison with serum Ca125, transvaginal sonography (TVS), and presence of intestinal symptoms., Methods: We included in this study 92 women undergoing surgery for symptomatic DIE. Preoperative evaluation included clinical history, Ca125 serum value, and TVS. CTC was performed in 37/92 patients (40.2%), and the results were compared to the other preoperative tools and to surgical exploration, considered the clinical reference standard., Results: Surgery confirmed bowel endometriosis in 49/92 subjects (53.3%). Presence of intestinal symptoms, serum Ca125 values, and TVS were significantly correlated to intestinal involvement, but CTC had the highest accuracy in detecting bowel endometriosis with a sensitivity of 68%, a specificity of 67%, a PPV of 81%, and a NPV of 50% (P = 0.04)., Conclusions: CTC proved to be an accurate and low invasive imaging technique to detect DIE of the bowel and compared favorably with clinical evaluation, serum Ca125 determination, and TVS.

Aim: Full-thickness laparo-endoscopic excision (FLEX) is a new technique developed for the full-thickness excision of colonic adenomas and, potentially, early cancer, avoiding the need for colectomy. FLEX requires accurate preoperative characterization of three key morphological features of the tumour, including its relation to the mesenteric border, its diameter and the circumferential extent of involvement of the bowel wall. This study evaluated the accuracy of CT colonography (CTC) for the assessment of these features in early colonic tumours., Method: Consecutive patients undergoing CTC prior to colonic resection for complex benign polyps or UICC Stage 1 cancer were retrospectively analysed by two specialist gastrointestinal radiologists blinded to the subsequent histopathological findings. The location of the tumour in relation to the mesenteric border, its maximum diameter and the circumferential extent of involvement of the colonic wall were correlated with the histopathological examination of the surgical resection specimen. Pearson's correlation coefficient (r) and Kappa agreement (κ) were used to compare the maximum diameter and the circumferential extent of involvement of the colonic wall., Results: Twenty-eight patients with early colonic neoplasia were included. All had had a surgical segmental resection. Four had a benign adenoma and 24 had a TNM Stage 1 cancer. Histopathological assessment of the resected surgical specimen showed that 21 of the 28 lesions were located on the mesenteric border. The median diameter was 35 (interquartile range 28-42) mm; 13 lesions involved less than one-third of the circumference, 11 between one and two-thirds and four more than two-thirds. CTC correctly identified the location of the lesion in relation to the mesenteric border in all 28 cases. Correlation between CTC and histopathology was good for the assessment of the maximum diameter of the lesion (r = 0.81) and the circumferential extent of involvement of the colonic wall (κ = 0.76)., Conclusion: CTC can accurately assess the key morphological features for the selection of patients with early colonic neoplasia for full-thickness laparo-endoscopic excision., (Colorectal Disease © 2016 The Association of Coloproctology of Great Britain and Ireland.)

Importance: Colorectal cancer (CRC) remains a significant cause of morbidity and mortality in the United States., Objective: To systematically review the effectiveness, diagnostic accuracy, and harms of screening for CRC., Data Sources: Searches of MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials for relevant studies published from January 1, 2008, through December 31, 2014, with surveillance through February 23, 2016., Study Selection: English-language studies conducted in asymptomatic populations at general risk of CRC., Data Extraction and Synthesis: Two reviewers independently appraised the articles and extracted relevant study data from fair- or good-quality studies. Random-effects meta-analyses were conducted., Main Outcomes and Measures: Colorectal cancer incidence and mortality, test accuracy in detecting CRC or adenomas, and serious adverse events., Results: Four pragmatic randomized clinical trials (RCTs) evaluating 1-time or 2-time flexible sigmoidoscopy (n = 458,002) were associated with decreased CRC-specific mortality compared with no screening (incidence rate ratio, 0.73; 95% CI, 0.66-0.82). Five RCTs with multiple rounds of biennial screening with guaiac-based fecal occult blood testing (n = 419,966) showed reduced CRC-specific mortality (relative risk [RR], 0.91; 95% CI, 0.84-0.98, at 19.5 years to RR, 0.78; 95% CI, 0.65-0.93, at 30 years). Seven studies of computed tomographic colonography (CTC) with bowel preparation demonstrated per-person sensitivity and specificity to detect adenomas 6 mm and larger comparable with colonoscopy (sensitivity from 73% [95% CI, 58%-84%] to 98% [95% CI, 91%-100%]; specificity from 89% [95% CI, 84%-93%] to 91% [95% CI, 88%-93%]); variability and imprecision may be due to differences in study designs or CTC protocols. Sensitivity of colonoscopy to detect adenomas 6 mm or larger ranged from 75% (95% CI, 63%-84%) to 93% (95% CI, 88%-96%). On the basis of a single stool specimen, the most commonly evaluated families of fecal immunochemical tests (FITs) demonstrated good sensitivity (range, 73%-88%) and specificity (range, 90%-96%). One study (n = 9989) found that FIT plus stool DNA test had better sensitivity in detecting CRC than FIT alone (92%) but lower specificity (84%). Serious adverse events from colonoscopy in asymptomatic persons included perforations (4/10,000 procedures, 95% CI, 2-5 in 10,000) and major bleeds (8/10,000 procedures, 95% CI, 5-14 in 10,000). Computed tomographic colonography may have harms resulting from low-dose ionizing radiation exposure or identification of extracolonic findings., Conclusions and Relevance: Colonoscopy, flexible sigmoidoscopy, CTC, and stool tests have differing levels of evidence to support their use, ability to detect cancer and precursor lesions, and risk of serious adverse events in average-risk adults. Although CRC screening has a large body of supporting evidence, additional research is still needed.

CT Colonography was first introduced to Ireland in 1999. Our aim of this study is to review current CT Colonography practices in the Republic of Ireland. A questionnaire on CT Colonography practice was sent to all non-maternity adult radiology departments in the Republic of Ireland with a CT scanner. The results are interpreted in the context of the recommendations on CT Colonography quality standards as published by the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus statement in the journal of European Radiology in 2013. Thirty centres provide CT Colonography; 21 of which responded (70%). Each centre performs median 90 studies per year; the majority follow accepted patient preparation and image acquisition protocols. Seventy-six percent of the centres repsonded that the majority of patients imaged are symptomatic. Of the 51 consultant radiologists reading CT Colonography, 37 (73%) have attended a CT Colonography course. In 17 (81%) of the centres the studies are single read although 81% of the centres have access to a second radiologist's opinion. Fourteen (67%) of the centres reported limited access to CT scanner time as the major limiting factor to expanding their service. CT Colonography is widely available in Ireland and is largely performed in accordance with European recommendations.

Objectives: This study aimed to evaluate the prevalence of colonic diverticula according to age, gender, distribution, disease extension and symptoms with CT colonography (CTC)., Methods: The study population included 1091 consecutive patients who underwent CTC. Patients with diverticula were retrospectively stratified according to age, gender, clinical symptoms and colonic segment involvement. Extension of colonic diverticula was evaluated using a three-point quantitative scale. Using this data, a multivariate regression analysis was applied to investigate the existence of any correlation among variables., Results: Colonic diverticula were observed in 561 patients (240 men, mean age 68 ± 12 years). Symptomatic uncomplicated diverticular disease (SUDD) was present in 47.4% of cases. In 25.6% of patients ≤40 years, at least one diverticulum in the colon was observed. Prevalence of right-sided diverticula in patients >60 years was 14.2% in caecum and 18.5% in ascending colon. No significant difference was found between symptomatic and asymptomatic patients regarding diverticula prevalence and extension. No correlation was present between diverticula extension and symptoms., Conclusion: The incidence of colonic diverticula appears to be greater than expected. Right colon diverticula do not appear to be an uncommon finding, with their prevalence increasing with patient age. SUDD does not seem to be related to diverticula distribution and extension., Key Points: Incidence of colonic diverticula appears to be greater than expected. Right colon diverticula do not appear to be an uncommon finding. SUDD does not seem to be related to diverticula distribution and extension.

Background: Population screening for colorectal cancer (CRC) is widely adopted, but the preferred strategy is still under debate. We aimed to compare reduced (r-CTC) and full cathartic preparation CT colonography (f-CTC), fecal immunochemical test (FIT), and optical colonoscopy (OC) as primary screening tests for CRC., Methods: Citizens of a district of Florence, Italy, age 54 to 65 years, were allocated (8:2.5:2.5:1) with simple randomization to be invited by mail to one of four screening interventions: 1) biennial FIT for three rounds, 2) r-CTC, 3) f-CTC, 4) OC. Patients tested positive to FIT or CTC (at least one polyp ≥6mm) were referred to OC work-up. The primary outcomes were participation rate and detection rate (DR) for cancer or advanced adenoma (advanced neoplasia). All statistical tests were two-sided., Results: Sixteen thousand eighty-seven randomly assigned subjects were invited to the assigned screening test. Participation rates were 50.4% (4677/9288) for first-round FIT, 28.1% (674/2395) for r-CTC, 25.2% (612/2430) for f-CTC, and 14.8% (153/1036) for OC. All differences between groups were statistically significant (P = .047 for r-CTC vs f-CTC; P < .001 for all others). DRs for advanced neoplasia were 1.7% (79/4677) for first-round FIT, 5.5% (37/674) for r-CTC, 4.9% (30/612) for f-CTC, and 7.2% (11/153) for OC. Differences in DR between CTC groups and FIT were statistically significant (P < .001), but not between r-CTC and f-CTC (P = .65)., Conclusions: Reduced preparation increases participation in CTC. Lower attendance and higher DR of CTC as compared with FIT are key factors for the optimization of its role in population screening of CRC., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Colorectal cancer is a leading cause of mortality and morbidity in Ontario. Most cases of colorectal cancer are preventable through early diagnosis and the removal of precancerous polyps. Colon capsule endoscopy is a non-invasive test for detecting colorectal polyps., Objectives: The objectives of this analysis were to evaluate the cost-effectiveness and the impact on the Ontario health budget of implementing colon capsule endoscopy for detecting advanced colorectal polyps among adult patients who have been referred for computed tomographic (CT) colonography., Methods: We performed an original cost-effectiveness analysis to assess the additional cost of CT colonography and colon capsule endoscopy resulting from misdiagnoses. We generated diagnostic accuracy data from a clinical evidence-based analysis (reported separately), and we developed a deterministic Markov model to estimate the additional long-term costs and life-years lost due to false-negative results. We then also performed a budget impact analysis using data from Ontario administrative sources. One-year costs were estimated for CT colonography and colon capsule endoscopy (replacing all CT colonography procedures, and replacing only those CT colonography procedures in patients with an incomplete colonoscopy within the previous year). We conducted this analysis from the payer perspective., Results: Using the point estimates of diagnostic accuracy from the head-to-head study between colon capsule endoscopy and CT colonography, we found the additional cost of false-positive results for colon capsule endoscopy to be $0.41 per patient, while additional false-negatives for the CT colonography arm generated an added cost of $116 per patient, with 0.0096 life-years lost per patient due to cancer. This results in an additional cost of $26,750 per life-year gained for colon capsule endoscopy compared with CT colonography. The total 1-year cost to replace all CT colonography procedures with colon capsule endoscopy in Ontario is about $2.72 million; replacing only those CT colonography procedures in patients with an incomplete colonoscopy in the previous year would cost about $740,600 in the first year., Limitations: The difference in accuracy between colon capsule endoscopy and CT colonography was not statistically significant for the detection of advanced adenomas (≥ 10 mm in diameter), according to the head-to-head clinical study from which the diagnostic accuracy was taken. This leads to uncertainty in the economic analysis, with results highly sensitive to changes in diagnostic accuracy., Conclusions: The cost-effectiveness of colon capsule endoscopy for use in patients referred for CT colonography is $26,750 per life-year, assuming an increased sensitivity of colon capsule endoscopy. Replacement of CT colonography with colon capsule endoscopy is associated with moderate costs to the health care system.

Objectives: The objectives are to describe the disadvantages of the area under the receiver operating characteristic curve (ROC AUC) to measure diagnostic test performance and to propose an alternative based on net benefit., Methods: We use a narrative review supplemented by data from a study of computer-assisted detection for CT colonography., Results: We identified problems with ROC AUC. Confidence scoring by readers was highly non-normal, and score distribution was bimodal. Consequently, ROC curves were highly extrapolated with AUC mostly dependent on areas without patient data. AUC depended on the method used for curve fitting. ROC AUC does not account for prevalence or different misclassification costs arising from false-negative and false-positive diagnoses. Change in ROC AUC has little direct clinical meaning for clinicians. An alternative analysis based on net benefit is proposed, based on the change in sensitivity and specificity at clinically relevant thresholds. Net benefit incorporates estimates of prevalence and misclassification costs, and it is clinically interpretable since it reflects changes in correct and incorrect diagnoses when a new diagnostic test is introduced., Conclusions: ROC AUC is most useful in the early stages of test assessment whereas methods based on net benefit are more useful to assess radiological tests where the clinical context is known. Net benefit is more useful for assessing clinical impact., Key Points: • The area under the receiver operating characteristic curve (ROC AUC) measures diagnostic accuracy. • Confidence scores used to build ROC curves may be difficult to assign. • False-positive and false-negative diagnoses have different misclassification costs. • Excessive ROC curve extrapolation is undesirable. • Net benefit methods may provide more meaningful and clinically interpretable results than ROC AUC.

Objectives: Screening decreases colorectal cancer (CRC) mortality. The national press has scrutinized colonoscopy charges. Little systematic evidence exists on colorectal testing and payments among commercially insured persons. Our aim was to characterize outpatient colorectal testing utilization and payments among commercially insured US adults., Methods: We conducted an observational cohort study of outpatient colorectal test utilization rates, indications, and payments among 21 million 18-64-year-old employees and dependants with noncapitated group health insurance provided by 160 self-insured employers in the 2009 Truven MarketScan Databases., Results: Colonoscopy was the predominant colorectal test. Among 50-64-year olds, 12% underwent colonoscopy in 1 year. Most fecal tests and colonoscopies were associated with screening/surveillance indications. Testing rates were higher in women, and increased with age. Mean payments for fecal occult blood and immunochemical tests were $5 and $21, respectively. Colonoscopy payments varied between and within sites of service. Mean payments for diagnostic colonoscopy in an office, outpatient hospital facility, and ambulatory surgical center were $586 (s.d. $259), $1,400 (s.d. $681), and $1,074 (s.d. $549), respectively. Anesthesia and pathology services accompanied 35 and 52% of colonoscopies, with mean payments of $494 (s.d. $354) and $272 (s.d. $284), respectively. Mean payments for the most prevalent colonoscopy codes were 1.4- to 1.9-fold the average Medicare payments., Conclusions: Most outpatient colorectal testing among commercially insured adults was associated with screening or surveillance. Payments varied widely across sites of service, and payments for anesthesia and pathology services contributed substantially to total payments. Cost-effectiveness analyses of CRC screening have relied on Medicare payments as proxies for costs, but cost-effectiveness may differ when analyzed from the perspectives of Medicare or commercial insurers.

Aim: To describe our experience using a 5 year audit of computed tomography colonography (CTC) practice and identify factors that influence diagnostic performance to guide implementation in other centres., Material and Methods: Consecutive patients referred for CTC at a single institution over a 5 year period were identified, and reporting rates and positive predictive value (PPV) calculated for small polyps, large polyps, and colorectal cancer. Diagnostic performance was compared using the Chi-squared test, and trends over time were examined with logistic regression. The effect of faecal tagging and an intravenous spasmolytic were investigated using Fisher's exact test., Results: In total, 4355 CTC examinations were performed. Overall reporting rates and PPV were 17% and 92%, respectively. Negative predictive value (NPV) for cancer was 99.9%. A significant decrease in reporting rate (p < 0.001) was accompanied by an increase in PPV for small polyps (p = 0.02) following the introduction of faecal tagging. Adequacy rates for CTC improved over time (96% to 99%), with improved adequacy rates when using a spasmolytic, 98% versus 96% without. A significant difference in reporting rates, but not PPV, was found between radiologists., Conclusion: Accurate colonic investigation using CTC can be delivered safely to a high-risk patient population at a single centre. Faecal tagging and an intravenous spasmolytic improve diagnostic performance., (Copyright © 2014. Published by Elsevier Ltd.)

Objective: To examine use of CT colonography (CTC) in the English Bowel Cancer Screening Programme (BCSP) and investigate detection rates., Design: Retrospective analysis of routinely coded BCSP data. Guaiac faecal occult blood test (gFOBt)-positive screenees undergoing CTC from June 2006 to July 2012 as their first-line colonic investigation were included. Abnormalities found at CTC, subsequent polyp, adenoma and cancer detection and positive predictive value (PPV) were calculated. Detection rates were compared with those observed in gFOBt-positive screenees investigated by colonoscopy. Multilevel logistic regression was used to examine factors associated with variable detection., Results: 2731 screenees underwent CTC. Colorectal cancer (CRC) or polyps were suspected in 1027 individuals (37.6%; 95% CI 33.8% to 41.4%); 911 of these underwent confirmatory testing. 124 screenees had CRC (4.5%) and 533 had polyps (19.5%), 468 adenomatous (17.1%). Overall detection was 24.1% (95% CI 21.5% to 26.6%) for CRC or polyps and 21.7% (95% CI 19.2% to 24.1%) for CRC or adenoma. Advanced neoplasia was detected in 504 screenees (18.5%; 95% CI 16.1% to 20.8%). PPV for CRC or polyp was 72.1% (95% CI 66.6% to 77.6%). By comparison, 9.0% of 72 817 screenees undergoing colonoscopy had cancer and 50.6% had polyps; advanced neoplasia was detected in 32.7%. CTC detection rates and PPV were higher at centres with experienced radiologists (>1000 examinations) and at high-volume centres (>175 cases/radiologist/annum). Centres using three-dimensional interpretation detected more neoplasia., Conclusions: In the BCSP, detection rates after positive gFOBt are lower for CTC than colonoscopy, although populations undergoing the two tests are different. Centres with more experienced radiologists have higher detection and accuracy. Rigorous quality assurance of BCSP radiology is needed.

Objectives: The objective of this study was to prospectively compare diagnostic performance and time efficiency of a double-reading paradigm in which a first-reader computer-aided detection (CAD) is followed by a fast 2-dimensional review (DR FR-CAD) with those of a double reading with second-reader CAD (SR CAD)., Materials and Methods: The local ethical committee approved this study. Consecutive immunological patients who have positive results for fecal immunological test who were scheduled for colonoscopy were enrolled for a 10-month period. Computed tomographic colonography studies were read with CAD (CAD COLON-1.20; im3D, Turin, Italy) by using both SR CAD (applied after unassisted interpretation primary 2-dimensional) and DR FR-CAD (CAD-prompts evaluation followed by a fast 2-dimensional review) in randomized order with the radiologist for each reading paradigm masked to the other reader's results.Per-patient sensitivity and specificity of unassisted and CAD-assisted readings for detecting 6-mm adenomas or larger were calculated by using unblinding colonoscopy as reference standard. Reporting times were also calculated. Pairwise comparisons were performed., Results: A total of 182 participants (median age, 65 years; range, 58-76) were included in the final analysis. Of these, 93 (51%) had at least 1 cancer or a 6-mm adenoma or larger. At the 6-mm threshold, sensitivity of unassisted reading (79.6%; 95% confidence interval [CI], 69.9-87.2) increased significantly with the use of both SR CAD (86.0%; 95% CI, 77.3%-92.3%) and DR FR-CAD (89.2%; 95% CI, 81.1%-94.7%), without differences between CAD readings (P = 0.500). No significant differences in specificity among the 3 paradigms were observed. Double reading with first-reader CAD required less reading time than that for SR CAD (378 vs 496; Δ118 seconds; P < 0.001) and was 59 seconds longer than the unassisted reading (P = 0.058)., Conclusions: When compared with unassisted reading, a double-reading paradigm in which first-reader CAD is followed by a fast 2-dimensional review improves the adenoma detection rate to the same level achieved by a second-reader CAD while decreasing reporting times.

Objectives: The majority of recent cost-effectiveness reviews concluded that computerised tomographic colonography (CTC) is not a cost-effective colorectal cancer (CRC) screening strategy yet. The objective of this review is to examine cost-effectiveness of CTC versus optical colonoscopy (COL) for CRC screening and identify the main drivers influencing cost-effectiveness due to the emergence of new research., Methods: A systematic review was conducted for cost-effectiveness studies comparing CTC and COL as a screening tool and providing outcomes in life-years saved, published between January 2006 and November 2012., Results: Nine studies were included in the review. There was considerable heterogeneity in modelling complexity and methodology. Different model assumptions and inputs had large effects on resulting cost-effectiveness of CTC and COL. CTC was found to be dominant or cost-effective in three studies, assuming the most favourable scenario. COL was found to be not cost effective in one study., Conclusions: CTC has the potential to be a cost-effective CRC screening strategy when compared to COL. The most important assumptions that influenced the cost-effectiveness of CTC and COL were related to CTC threshold-based reporting of polyps, CTC cost, CTC sensitivity for large polyps, natural history of adenoma transition to cancer, AAA parameters and importantly, adherence. There is a strong need for a differential consideration of patient adherence and compliance to CTC and COL. Recent research shows that laxative-free CTC screening has the potential to become a good alternative screening method for CRC as it can improve patient uptake of screening., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Background: Despite the expected health benefits of colorectal cancer screening programs, participation rates remain low in countries that have implemented such a screening program. The perceived benefits and risks of the colorectal cancer screening technique are likely to influence the decision to attend the screening program. Besides the diagnostic accuracy and the risks of the screening technique, which can affect the health of the participants, additional factors, such as the burden of the test, may impact the individuals' decisions to participate. To maximise the participation rate of a screening program for a new colorectal cancer program in the Netherlands, it is important to know the preferences of the screening population for alternative screening techniques., Objective: The aim of this study was to explore the impact of preferences for particular attributes of the screening tests on the intention to attend a colorectal cancer screening program., Methods: We used a web-based questionnaire to elicit the preferences of the target population for a selection of colon-screening techniques. The target population consisted of Dutch men and women aged 55-75 years. The analytic hierarchy process (AHP), a technique for multi-criteria analysis, was used to estimate the colorectal cancer screening preferences. Respondents weighted the relevance of five criteria, i.e. the attributes of the screening techniques: sensitivity, specificity, safety, inconvenience, and frequency of the test. With regard to these criteria, preferences were estimated between four alternative screening techniques, namely, immunochemical fecal occult blood test (iFOBT), colonoscopy, sigmoidoscopy, and computerized tomographic (CT) colonography. A five-point ordinal scale was used to estimate the respondents' intention to attend the screening. We conducted a correlation analysis on the preferences for the screening techniques and the intention to attend., Results: We included 167 respondents who were consistent in their judgments of the relevance of the criteria and their preferences for the screening techniques. The most preferred screening method for the national screening program was CT colonography. Sensitivity (weight = 0.26) and safety (weight = 0.26) were the strongest determinants of the overall preferences for the screening techniques. However, the screening test with the highest intention to attend was iFOBT. Inconvenience (correlation [r] = 0.69), safety (r = 0.58), and the frequency of the test (r = 0.58) were most strongly related to intention to attend., Conclusions: The multi-criteria decision analysis revealed the attributes of the screening techniques that are most important so as to increase intention to participate in a screening program. Even though the respondents may recognize the high importance of diagnostic effectiveness in the long term, their short-term decision to attend the screening tests may be less driven by this consideration. Our analysis suggests that inconvenience, safety, and frequency of the test are the strongest technique-related determinants of the respondents' intention to participate in colorectal screening programs.

Aim: To determine the sensitivity of computed tomographic colonography (CTC) in the detection of colorectal cancer in our population and evaluate the reasons why these lesions may be missed on CTC., Methods: All patients who underwent CTC in the 65-month period from 1 January 2004 to 1 July 2009 were included in the analysis. Demographic data and CTC findings were recorded, according to the CT Colonography Reporting and Data System. Data were cross-matched with the National Cancer Registry results for colorectal cancer cases between 1 January 2004 and 1 October 2009, 3 months longer to include any delayed diagnoses., Results: There were 2026 consecutive CTC patients, comprising 52.6% female, average age of 60 years; range 19-87. Approximately 84% were symptomatic. There were 45 confirmed colorectal cancers among this patient group in the National Cancer Registry during the relevant time period compared with 43 suspected cancers on CTC, giving a miss rate of 2 of 45, or 4.4%., Conclusion: The sensitivity of 95% for CTC in the detection of colorectal cancer compares favourably with the published national and international data., (© 2013 The Authors. Journal of Medical Imaging and Radiation Oncology © 2013 The Royal Australian and New Zealand College of Radiologists.)

Objective: Cathartic bowel preparation is a major barrier for colorectal cancer screening. We examined noncathartic CT colonography (CTC) quality and performance using four similar bowel-tagging regimens in an asymptomatic screening cohort., Subjects and Methods: This prospective study included 564 asymptomatic subjects who underwent noncathartic CTC without dietary modification but with 21 g of barium with or without iodinated oral contrast material (four regimens). The quality of tagging with oral agents was evaluated. A gastrointestinal radiologist evaluated examinations using primary 2D search supplemented by electronic cleansing (EC) and 3D problem solving. Results were compared with complete colonoscopy findings after bowel purgation and with retrospective unblinded evaluation in 556 of the 564 (99%) subjects., Results: Of the 556 subjects, 7% (37/556) and 3% (16/556) of patients had 52 and 20 adenomatous polyps ≥ 6 and ≥ 10 mm, respectively. The addition of iodine significantly improved the percentage of labeled stool (p ≤ 0.0002) and specificity (80% vs 89-93%, respectively; p = 0.046). The overall sensitivity of noncathartic CTC for adenomatous polyps ≥ 6 mm was 76% (28/37; 95% CI, 59-88%), which is similar to the sensitivity of the iodinated regimens with most patients (sensitivity: 231 patients, 74% [14/19; 95% CI, 49-91%]; 229 patients, 80% [12/15; 95% CI, 52-96%]). The negative predictive value was 98% (481/490), and the lone cancer was detected (0.2%, 1/556). EC was thought to improve conspicuity of 10 of 21 visible polyps ≥ 10 mm., Conclusion: In this prospective study of asymptomatic subjects, the per-patient sensitivity of noncathartic CTC for detecting adenomas ≥ 6 mm was approximately 76%. Inclusion of oral iodine contrast material improves examination specificity and the percentage of labeled stool. EC may improve polyp conspicuity.

Background: Colorectal cancer (CRC) is a common problem in New Zealand and there is significant pressure on colonoscopy resources. Lower gastrointestinal symptoms are common in the community hence the appropriate selection of patients for colonoscopy is problematic. The Canterbury District Health Board recently developed the Canterbury Colorectal Symptom Pathway (CCrSP) to attempt to improve prioritisation using a combination of presenting clinical features integrated into a scoring tool. This study describes that pathway and its outcomes over a 6-month period., Method: Following implementation of the CCrSP, all outpatient referrals receiving colonoscopy or Computerised Tomography Colonography (CTC) over a 6-month period were audited. The clinical features included in the referral, waiting time and outcome of investigation were recorded. Using the scoring tool, a score was calculated for all referrals and compared with outcome., Results: Some 1,369 procedures were performed during the study period. Of the symptomatic patients, 38 CRCs were diagnosed from 633 colonoscopies and 253 CTCs. Individual factors predictive for CRC were rectal bleeding (OR 2.1, 95%CI 1.1-4.2), iron deficiency anaemia (OR 3.2, 95%CI 1.6-6.3) and positive faecal occult blood test (OR 6.1, 95%CI 2.1-16.3). No CRCs were diagnosed in the group scoring below the pre-set threshold for investigation. Multiple logistic regression analysis demonstrated a 1 unit increase in score increased the likelihood of CRC by 7.2% (95%CI 4.4%-10.1%, p<0.001). Of the 11 CRCs suggested by CTC, there was one false positive. The follow up colonoscopy rate after CTC was 11.5% and further radiology was recommended in 7.9%., Conclusion: The CCrSP pathway was accurate for predicting CRC and offers a reliable triage tool. The scoring tool was both sensitive for CRC and predictive of the risk of CRC in patients who received colonoscopy or CTC.

Purpose: To perform external validation of a computer-assisted registration algorithm for prone and supine computed tomographic (CT) colonography and to compare the results with those of an existing centerline method., Materials and Methods: All contributing centers had institutional review board approval; participants provided informed consent. A validation sample of CT colonographic examinations of 51 patients with 68 polyps (6-55 mm) was selected from a publicly available, HIPAA compliant, anonymized archive. No patients were excluded because of poor preparation or inadequate distension. Corresponding prone and supine polyp coordinates were recorded, and endoluminal surfaces were registered automatically by using a computer algorithm. Two observers independently scored three-dimensional endoluminal polyp registration success. Results were compared with those obtained by using the normalized distance along the colonic centerline (NDACC) method. Pairwise Wilcoxon signed rank tests were used to compare gross registration error and McNemar tests were used to compare polyp conspicuity., Results: Registration was possible in all 51 patients, and 136 paired polyp coordinates were generated (68 polyps) to test the algorithm. Overall mean three-dimensional polyp registration error (mean ± standard deviation, 19.9 mm ± 20.4) was significantly less than that for the NDACC method (mean, 27.4 mm ± 15.1; P = .001). Accuracy was unaffected by colonic segment (P = .76) or luminal collapse (P = .066). During endoluminal review by two observers (272 matching tasks, 68 polyps, prone to supine and supine to prone coordinates), 223 (82%) polyp matches were visible (120° field of view) compared with just 129 (47%) when the NDACC method was used (P < .001). By using multiplanar visualization, 48 (70%) polyps were visible after scrolling ± 15 mm in any multiplanar axis compared with 16 (24%) for NDACC (P < .001)., Conclusion: Computer-assisted registration is more accurate than the NDACC method for mapping the endoluminal surface and matching the location of polyps in corresponding prone and supine CT colonographic acquisitions.

Purpose: To compare diagnostic performance and time efficiency of double-reading first-reader computer-aided detection (CAD) (DR FR CAD) followed by radiologist interpretation with that of an unassisted read using segmentally unblinded colonoscopy as reference standard., Materials and Methods: The local ethical committee approved this study. Written consent to use examinations was obtained from patients. Three experienced radiologists searched for polyps 6 mm or larger in 155 computed tomographic (CT) colonographic studies (57 containing 10 masses and 79 polyps ≥ 6 mm). Reading was randomized to either unassisted read or DR FR CAD. Data sets were reread 6 weeks later by using the opposite paradigm. DR FR CAD consists of evaluation of CAD prompts, followed by fast two-dimensional review for mass detection. CAD sensitivity was calculated. Readers' diagnoses and reviewing times with and without CAD were compared by using McNemar and Student t tests, respectively. Association between missed polyps and lesion characteristics was explored with multiple regression analysis., Results: With mean rate of 19 (standard deviation, 14; median, 15; range, 4-127) false-positive results per patient, CAD sensitivity was 90% for lesions 6 mm or larger. Readers' sensitivity and specificity for lesions 6 mm or larger were 74% (95% confidence interval [CI]: 65%, 84%) and 93% (95% CI: 89%, 97%), respectively, for the unassisted read and 77% (95% CI: 67%, 85%) and 90% (95% CI: 85%, 95%), respectively, for DR FR CAD (P = .343 and P = .189, respectively). Overall unassisted and DR FR CAD reviewing times were similar (243 vs 239 seconds; P = .623); DR FR CAD was faster when the number of CAD marks per patient was 20 or fewer (187 vs 220 seconds, P <01). Odds ratio of missing a polyp with CAD decreased as polyp size increased (0.6) and for polyps visible on both prone and supine scans (0.12); it increased for flat lesions (9.1)., Conclusion: DR FR CAD paradigm had similar performance compared with unassisted interpretation but better time efficiency when 20 or fewer CAD prompts per patient were generated.

Colorectal cancer (CRC) is responsible for 27,000 deaths and 65,000 new cancers in Germany each year, although this should be unnecessary as CRC is preventable because it is possible to remove the precursors, harmless polyps and adenomas. However, only 2.5 % of people in health insurance make use of screening colonoscopy annually so that it becomes necessary to check out other screening tests. The most commonly used test is the Guaiak-based test for fecal occult blood (gFOBT) which is highly specific but not very sensitive (only approximately 10 %). New immunological stool tests are more sensitive but the specificity is reduced from 90 % to approximately 80 %. Virtual colonoscopy based on computed tomography (CT) or magnetic resonance imaging (MRI) is comparable to endoscopy for diagnostics with overall accuracy rates of approximately 80-90 % for polyps larger than 5 mm but for radiation protection reasons CT is not usable in Germany and MRI is internationally not adequately established by large study trials. For the future there is much hope in molecular blood tests. It is of great importance that every physician is aware of the different tests, their strengths and weaknesses and advises all patients to use the different screening possibilities.

Background: Although the Centers for Medicare and Medicaid Services (CMS) denied coverage for screening computed tomography colonography (CTC) in March 2009, little is understood about whether CTC was targeted to the appropriate patient population prior to this decision., Objective: Evaluate patient characteristics and known relative clinical indications for screening CTC among patients who received CTC compared to optical colonoscopy (OC)., Design/participants: Cross-sectional study of all 10,538 asymptomatic Medicare beneficiaries who underwent CTC between January 2007 and December 2008, compared to a cohort of 160,113 asymptomatic beneficiaries who underwent OC, matched on county of residence and year of examination., Main Measures: Patient characteristics and known relative appropriate and inappropriate clinical indications for screening CTC., Key Results: CTC utilization was higher among women, patients > 65 years of age, white patients, and those with household income > 75 % (p = 0.001). Patients with relatively appropriate clinical indications for screening CTC were more likely to undergo CTC than OC including presumed incomplete OC (OR 80.7, 95 % CI 76.01-85.63); sedation risk (OR 1.11, 95 % CI 1.05-1.17); and chronic anticoagulation risk (OR 1.46, 95 % CI 1.38-1.54), after adjusting for patient characteristics and known clinical indications. Conversely, patients undergoing high-risk screening, an inappropriate indication, were less likely to receive CTC (OR 0.4, 95 % CI 0.37-0.42). Overall, 83 % of asymptomatic patients referred to CTC had at least one clinical indication relatively appropriate for CTC (8,772/10,538)., Conclusion: During the 2 years preceding CMS denial for screening, CTC was targeted to asymptomatic patients with relatively appropriate clinical indications for CTC/not receiving OC. However, CTC utilization was lower among certain demographic groups, including minority patients. These findings raise the possibility that future coverage of screening CTC might exacerbate disparities in colorectal cancer screening while increasing overall screening rates.

Aim: To retrospectively study the frequency and magnitude of complications associated with computed tomography (CT) colonography in clinical practice., Methods: A questionnaire on complications of CT colonography was sent to Italian public radiology departments identified as practicing CT colonography with a reasonable level of training. The frequency of complications and possible risk factors were retrospectively determined. Responses were collated and row frequencies determined. A multivariate analysis of the factors causing adverse events was also performed., Results: 40,121 examinations were performed in13 centers during the study period. No deaths were reported. Bowel perforations occurred in 0.02% (7 exams). All perforations were asymptomatic and occurred in patients undergoing manual insufflation. Five perforations (71%) occurred in procedures performed following a recent colonoscopy. There was no significant difference between perforations associated with rectal balloon (0.017%) and those that were not (0.02%). Complications related to vasovagal reaction (either with or without spasmolytic) occurred in 0.16% (63 exams). All vasovagal reactions resolved in less than 3h, without any sequelae., Conclusions: Perforation rate at CT colonography in Italy is comparable with elsewhere in the world, occurring regardless of the experience of radiology centers. Although the risk is very small, it may not be negligible when compared with the risk of diagnostic colonoscopy., (Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Background: Currently, there are no data on adherence to guidelines for colorectal cancer (CRC) screening in patients with a family history., Aim: We conducted a retrospective study to assess if such patients were being appropriately screened according to American Gastroenterological Association (AGA) guidelines., Methods: Two independent reviewers performed a comprehensive medical record review of family and CRC screening history on 362 adults with a family history of CRC in a first-degree relative who had recently undergone screening colonoscopy. The endpoint was appropriate initiation of screening and endoscopist-recommended subsequent screening intervals, as compared to AGA guideline recommendations., Results: Of 362 subjects, only 146 (40.3 %) were screened appropriately; 213 (58.9 %) had late initiation of screening (i.e., screening was started ≥5 years later than the age recommended by guidelines) and three (0.8 %) had premature initiation (i.e., screening was started ≥1 year too early). Of cases involving delayed screening initiation, 126 were not under primary care at the time when screening was supposed to have started, while most of the remaining received either no or incorrect screening recommendations from their primary care provider. Of 270 subjects with no neoplasia found on initial screening, 112 (41.5 %) had endoscopist-recommended subsequent screening intervals that were ≥2 years shorter than that recommended by guidelines. Results were similar if American Society of Gastrointestinal Endoscopy or American College of Gastroenterology guidelines were used., Conclusions: Patients with a family history often suffer from late initiation of screening and overly short endoscopist-recommended subsequent intervals for colonoscopy. Further education of patients and providers on screening recommendations may be helpful.

Purpose: To prospectively assess the performance of teleradiology-based CT colonography to screen a population group of an island, at average risk for colorectal cancer., Materials and Methods: A cohort of 514 patients living in Madeira, Portugal, was enrolled in the study. Institutional review board approval was obtained and all patients signed an informed consent. All patients underwent both CT colonography and optical colonoscopy. CT colonography was interpreted by an experienced radiologist at a remote centre using tele-radiology. Per-patient sensitivity, specificity, positive (PPV) and negative (NPV) predictive values with 95% confidence intervals (95%CI) were calculated for colorectal adenomas and advanced neoplasia ≥6 mm., Results: 510 patients were included in the study. CT colonography obtained a per-patient sensitivity, specificity, PPV and, NPV for adenomas ≥6 mm of 98.11% (88.6-99.9% 95% CI), 90.97% (87.8-93.4% 95% CI), 56.52% (45.8-66.7% 95% CI), 99.75% (98.4-99.9% 95% CI). For advanced neoplasia ≥6 mm per-patient sensitivity, specificity, PPV and, NPV were 100% (86.7-100% 95% CI), 87.07% (83.6-89.9% 95% CI), 34.78% (25.3-45.5% 95% CI) and 100% (98.8-100% 95% CI), respectively., Conclusion: In this prospective trial, teleradiology-based CT colonography was accurate to screen a patient cohort of a remote island, at average risk for colorectal cancer., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objective: To evaluate the level of informed decision making in a randomized controlled trial comparing colonoscopy and CT-colonography for colorectal cancer screening., Methods: 8844 citizens aged 50-75 were randomly invited to colonoscopy (n=5924) or CT-colonography (n=2920) screening. All invitees received an information leaflet. Screenees received a questionnaire within 4 weeks before the planned examination, non-screenees 4 weeks after the invitation. A decision was categorized as informed when characterized by sufficient decision-relevant knowledge and consistent with personal attitudes toward participation in screening., Results: Knowledge and attitude items were completed by 1032/1276 colonoscopy screenees (81%), by 698/4648 colonoscopy non-screenees (15%), by 824/982 CT-colonography screenees (84%) and by 192/1938 CT-colonography non-screenees (10%). 1027 colonoscopy screenees (>99%) and 815 CT-colonography screenees (99%) had adequate knowledge; 915 (89%) and 742 (90%) had a positive attitude. 675 non-screenees invited to colonoscopy (97%) and 182 invited to CT-colonography (95%) had adequate knowledge; 344 (49%) and 94 (49%) expressed a negative attitude., Conclusion: A large majority of screenees made an informed decision on participation. Almost half of responding non-screenees, made an uninformed decision, suggesting additional barriers to participation., Practice Implications: Efforts to understand the additional barriers will create opportunities to facilitate informed participation to colorectal cancer screening., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)