Colon capsule endoscopy: detection of colonic polyps compared with conventional colonoscopy and visualization of extracolonic pathologies

Colon capsule endoscopy polyp detection rate vs colonoscopy polyp detection rate: Systematic review and meta-analysis

BACKGROUND

Colon capsule endoscopy (CCE) is a modern, non-invasive method for large bowel visualization, offering a less invasive alternative to traditional colonoscopy (TC). While TC remains the gold standard for comprehensive large bowel assessment, including the detection and treatment of various conditions, the effectiveness of CCE in detecting polyps is less established.

AIM

To systematically review and compare the polyp detection rates (PDR) of CCE and TC.

METHODS

A systematic literature search was conducted using four scientific databases: CINAHL, MEDLINE via EBSCO, Cochrane Library, and MEDLINE/PubMed. A standardized search command was utilized to ensure consistency. Full papers were retrieved if they compared PDR between CCE and TC and involved patients over 18 years old. A meta-analysis was then conducted using the meta package in R software.

RESULTS

Initially, 339 articles were identified, with 128 duplicates and 15 non-English articles excluded, leaving 196 for screening. After further exclusions, 9 articles were included in the review. The meta-analysis revealed minimal differences in PDR between CCE and TC. The pooled PDR for TC was 0.61 (95%CI: 0.48–0.72), and for CCE, it was 0.61 (95%CI: 0.48–0.73). The overall comparison of the pooled PDR of both methods was 0.96 (95%CI: 0.90–1.02), indicating that CCE is non-inferior to TC.

CONCLUSION

CCE has emerged as a modern and safe diagnostic alternative to TC for polyp detection, demonstrating non-inferiority when compared to the conventional method.

TOP 100 and detection of colorectal lesions in colon capsule endoscopy: more than meets the eye

Colon capsule endoscopy (CCE) is a well-known method for the detection of colorectal lesions. Nevertheless, there are no studies reporting the accuracy of TOP 100, a CCE software tool, for the automatic detection of colorectal lesions in CCE. We aimed to evaluate the performance of TOP 100 in detecting colorectal lesions in patients submitted to CCE for incomplete colonoscopy compared with classic reading. A retrospective cohort study including adult patients submitted to CCE (PillCam COLON 2; Medtronic) for incomplete colonoscopy. Blinded for each other's evaluation, one experienced reader analyzed the TOP 100 images and the other performed classic reading to identify colorectal lesions. Detection of colorectal lesions, namely polyps, angioectasia, blood, diverticula, erosions/ulcers, neoplasia, and subepithelial lesions was assessed and TOP 100 performance was evaluated compared with the gold standard (classic reading). A total of 188 CCEs were included. Prevalence of colorectal lesions, polyps, angioectasia, blood, diverticula, erosions/ulcers, neoplasia, and subepithelial lesions were 77.7, 54.3, 8.5, 1.6, 50.0, 0.5, 0.5, and 1.1%, respectively. TOP 100 had a sensitivity of 92.5%, specificity of 69.1%, negative predictive value of 72.5%, positive predictive value of 91.2%, and accuracy of 87.2% for detecting colorectal lesions. TOP 100 had a sensitivity of 89.2%, specificity of 84.9%, negative predictive value of 86.9%, positive predictive value of 87.5%, and accuracy of 87.2% in detecting polyps. All colorectal lesions other than polyps were identified with 100% accuracy by TOP 100. TOP 100 has been shown to be a simple and useful tool in assisting the reader in the prompt identification of colorectal lesions in CCE.

Cost-utility analysis of expanding the colorectal cancer screening policy in Flanders

OBJECTIVE

Since 2013, Flanders has introduced a screening programme for colorectal cancer for all citizens aged between 50 and 74 years. The objective of this study was to assess the cost-utility of an expansion of the colorectal cancer screening policy in Flanders (Belgium) and to place these findings in the international context.

METHODS

Cost-utility analysis using high-detail data about screening participation, screening results, and epidemiological data, a Markov cohort model has been constructed to study long-term costs and effects. A cost-utility analysis was performed as a three-way comparison between current, expanded (from age 45 years), and no screening scenarios, from a societal and healthcare perspective. Robustness was assessed by both one-way and probabilistic sensitivity analyses.

RESULTS

Analyses show that both current and expanded screening result in quality-adjusted life years (QALY) gains and are mostly cost-saving. Overall, 97.5% of Incremental Cost-Effectiveness Ratios (ICERs) remained well below € 2000 per QALY for all comparisons. Parameters related to the colonoscopy that follows a positive test result such as compliance and cost are especially impactful on the cost-effectiveness.

CONCLUSIONS

Screening participation and screening costs have remained comparatively stable, making colorectal cancer screening a cost-effective (dominant) policy. Expanding the screen age to 45 years is also cost-effective (dominant) compared with current screening, albeit with a slimmer margin.

Sensing Mucus Physiological Property In Situ by Wireless Millimeter-Scale Soft Robots

The physiological property of mucus is an important biomarker for monitoring the human health conditions and helping understand disease development, as mucus property such as viscosity is highly correlated with inflammation and other diseases. However, it remains challenging to sense mucus viscosity using pure medical imaging. Collecting and analyzing mucus sample in vitro using flexible endoscopes and capsule endoscope robots is also challenging due to their difficulty of accessing very confined, tortuous, and small spaces, and the sample may not reflect the real mucus property. Here a novel method is proposed to enable sensing mucus viscosity in situ by wireless miniature sensors actuated by magnetic fields and tracked by medical imaging. These miniature viscosity sensors can be delivered with minimal invasion using a novel sensor delivery mechanism by controlling a magnetically actuated millimeter-scale soft climbing robot. As the soft robot can access confined and narrow spaces, and reliably deploy the sensor on soft tissue surfaces, multiple sensors can be delivered on soft biological tissues to sense biofluid viscosity spatiotemporally. The proposed minimally invasive robotic delivery and viscosity sensing method thus paves the way toward sensing biofluid properties deep inside the body for future disease monitoring and early diagnosis functions.

Colon Capsule Endoscopy in the Diagnosis of Colon Polyps: Who Needs a Colonoscopy?

Colon screening programs have reduced colon cancer mortality. Population screening should be minimally invasive, safe, acceptably sensitive, cost-effective, and scalable. The range of screening modalities include guaiac or immunochemical fecal occult blood testing and CT colonography and colonoscopy. A number of carefully controlled studies concur that second-generation capsule endoscopy has excellent sensitivity for polyp detection and a high negative predictive value. Colon capsules fulfill the screening expectation of safety, high sensitivity for polyp detection, and patient acceptance, and appear to straddle the divide between occult blood testing and colonoscopy. While meeting these criteria, there remains the challenges of scaling, capsule practitioner training, resource allocation, and implementing change of practice. Like CT colonography, capsule screening presents the clinician with a decision on the threshold for colonoscopy referral. Overall, colon capsules are an invaluable tool in polyp detection and colon screening and offer a filter that determines “who needs a colonoscopy?”.

Efficacy of bowel preparation regimens for colon capsule endoscopy: a systematic review and meta-analysis

Background and study aims  Colon capsule endoscopy (CCE) is an alternative to conventional colonoscopy (CC) in specific clinical settings. High completion rates (CRs) and adequate cleanliness rates (ACRs) are fundamental quality parameters if CCE is to be widely implemented as a CC equivalent diagnostic modality. We conducted a systematic review and meta-analysis to investigate the efficacy of different bowel preparations regimens on CR and ACR in CCE. Patients and methods  We performed a systematic literature search in PubMed, Embase, CINAHL, Web of Science, and the Cochrane Library. Data were independently extracted per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The primary outcome measures (CR, ACR) were retrieved from the individual studies and pooled event rates were calculated. Results  Thirty-four observational (OBS) studies (n = 3,789) and 12 randomized clinical trials (RCTs) (n = 1,214) comprising a total 5,003 patients were included. The overall CR was 0.798 (95 % CI, 0.764-0.828); the highest CRs were observed with sodium phosphate (NaP) + gastrografin booster (n = 2, CR = 0.931, 95 % CI, 0.820-0.976). The overall ACR was 0.768 (95 % CI, 0.735-0.797); the highest ACRs were observed with polyethylene glycol (PEG) + magnesium citrate (n = 4, ER = 0.953, 95 % CI, 0.896-0.979). Conclusions  In the largest meta-analysis on CCE bowel preparation regimens, we found that both CRs and ACRs are suboptimal compared to the minimum recommended standards for CC. PEG laxative and NaP booster were the most commonly used but were not associated with higher CRs or ACRs. Well-designed studies on CCE should be performed to find the optimal preparation regimen.

Multicentre, prospective, randomised study comparing the diagnostic yield of colon capsule endoscopy versus CT colonography in a screening population (the TOPAZ study)

OBJECTIVE

Colon capsule endoscopy (CCE) has shown promise for colorectal neoplasia detection compared with optical colonoscopy (OC), but has not been compared with other screening tests in average risk screening patients.

DESIGN

Patients 50 to 75 years of age (African Americans, 45-75 years) were randomised to CCE or CT colonography (CTC) and subsequent blinded OC. The primary endpoint was diagnostic yield of polyps ≥6 mm with CCE or CTC. Secondary endpoints included accuracy for size and histology, examination completeness, number/proportion of subjects with polyps and adenomas ≥6 mm and ≥10 mm, subject satisfaction and safety.

RESULTS

From 320 enrolled subjects, data from 286 (89.4%) were evaluable. The proportion of subjects with any polyp ≥6 mm confirmed by OC was 31.6% for CCE versus 8.6% for CTC (pPr non-inferiority and superiority=0.999). The diagnostic yield of polyps ≥10 mm was 13.5% with CCE versus 6.3% with CTC (pPr non-inferiority=0.9954). The sensitivity and specificity of CCE for polyps ≥6 mm was 79.2% and 96.3% while that of CTC was 26.8% and 98.9%. The sensitivity and specificity of CCE for polyps ≥10 mm was 85.7% and 98.2% compared with 50% and 99.1% for CTC. Both tests were well tolerated/safe.

CONCLUSION

CCE was superior to CTC for detection of polyps ≥6 mm and non-inferior for identification of polyps ≥10 mm. CCE should be considered comparable or superior to CTC as a colorectal neoplasia screening test, although neither test is as effective as OC.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov no: NCT02754661.

Diagnostic accuracy of capsule endoscopy compared with colonoscopy for polyp detection: systematic review and meta-analyses

BACKGROUND

Colon capsule endoscopy (CCE) is a technology that might contribute to colorectal cancer (CRC) screening programs as a filter test between fecal immunochemical testing and standard colonoscopy. The aim was to systematically review the literature for studies investigating the diagnostic yield of second-generation CCE compared with standard colonoscopy.

METHODS

A systematic literature search was performed in PubMed, Embase, and Web of Science. Study characteristics including quality of bowel preparation and completeness of CCE transits were extracted. Per-patient sensitivity and specificity were extracted for polyps (any size, ≥ 10 mm, ≥ 6 mm) and lesion characteristics. Meta-analyses of diagnostic yield were performed.

RESULTS

The literature search revealed 1077 unique papers and 12 studies were included. Studies involved a total of 2199 patients, of whom 1898 were included in analyses. The rate of patients with adequate bowel preparation varied from 40 % to 100 %. The rates of complete CCE transit varied from 57 % to 100 %. Our meta-analyses demonstrated that mean (95 % confidence interval) sensitivity, specificity, and diagnostic odds ratio were: 0.85 (0.73-0.92), 0.85 (0.70-0.93), and 30.5 (16.2-57.2), respectively, for polyps of any size; 0.87 (0.82-0.90), 0.95 (0.92-0.97), and 136.0 (70.6-262.1), respectively, for polyps ≥ 10 mm; and 0.87 (0.83-0.90), 0.88 (0.75-0.95), and 51.1 (19.8-131.8), respectively, for polyps ≥ 6 mm. No serious adverse events were reported for CCE.

CONCLUSION

CCE had high sensitivity and specificity for per-patient polyps compared with standard colonoscopy However, the relatively high rate of incomplete investigations limits the application of CCE in a CRC screening setting.

Scoring Systems for Clinical Colon Capsule Endoscopy-All You Need to Know

In the constantly developing era of minimal diagnostic invasiveness, the role of colon capsule endoscopy in colonic examination is being increasingly recognised, especially in the context of curtailed endoscopy services due to the COVID-19 pandemic. It is a safe diagnostic tool with low adverse event rates. As with other endoscopic modalities, various colon capsule endoscopy scores allow the standardisation of reporting and reproducibility. As bowel cleanliness affects CCE’s diagnostic yield, a few operator-dependent scores (Leighton–Rex and CC-CLEAR scores) and a computer-dependent score (CAC score) have been developed to grade bowel cleanliness objectively. CCE can be used to monitor IBD mucosal disease activity through the UCEIS and the panenteric CECDAIic score for UC and CD, respectively. CCE may also have a role in CRC screening, given similar sensitivity and specificity rates to conventional colonoscopy to detect colonic polyps ≥ 10 mm and CRC. Given CCE’s diagnostic yield and reproducible clinical scores with high inter-observer agreements, CCE is fast becoming a suitable alternative to conventional colonoscopy in specific patient populations.

Current status of colon capsule endoscopy

While both the annual incidence and mortality of colorectal cancer are slowly but steadily decreasing in the United States, the incidence of such malignancy is increasing in Japan. Thus, controlling colorectal cancer in Japan is a major concern. In 2006, colon capsule endoscopy was first introduced by Eliakim et al. First-generation colon capsule endoscopy had a moderate sensitivity for detecting polyps of more than 6 mm. Thus, second-generation colon capsule endoscopy was developed to achieve higher sensitivity. Colonoscopy is the gold standard tool for colorectal cancer surveillance. With an improvement in the imaging function, the performance of second-generation colon capsule endoscopy is almost as satisfactory as that of colonoscopy. Certain situations, such as incomplete colonoscopy and contraindication for use of sedation, can benefit from colon capsule endoscopy. Colon capsule endoscopy requires a more extensive bowel preparation than colonoscopy and computed tomography colonography because it requires laxatives not only for bowel cleansing but also for promoting the excretion of the capsule. Another problem with colon capsule endoscopy includes the burden of reading and interpretation and overlook of the lesions. Currently, the development of automatic diagnosis of colon capsule endoscopy using artificial intelligence is still under progress. Although the available guidelines do not support the use of colon capsule endoscopy for inflammatory bowel disease, the possible application of colon capsule endoscopy is ulcerative colitis. This review article summarizes and focuses on the current status of colon capsule endoscopy for colorectal cancer screening and the possibility for its applicability on inflammatory bowel disease.

Second-generation colon capsule endoscopy for detection of colorectal polyps: Systematic review and meta-analysis of clinical trials

Background and study aims  Adherence to colorectal cancer (CRC) screening is still unsatisfactory in many countries, thereby limiting prevention of CRC. Colon capsule endoscopy (CCE), a minimally invasive procedure, could be an alternative to fecal immunochemical tests or optical colonoscopy for CRC screening, and might increase adherence in CRC screening. This systematic review and meta-analysis evaluates the diagnostic accuracy of CCE compared to optical colonoscopy (OC) as the gold standard, adequacy of bowel preparation regimes and the patient perspective on diagnostic measures. Methods  We conducted a systematic literature search in PubMed, EMBASE and the Cochrane Register for Clinical Trials. Pooled estimates for sensitivity, specificity and the diagnostic odds ratio with their respective 95 % confidence intervals (CI) were calculated for studies providing sufficient data. Results  Of 840 initially identified studies, 13 were included in the systematic review and up to 9 in the meta-analysis. The pooled sensitivities and specificities for polyps ≥ 6 mm were 87 % (95 % CI: 83 %-90 %) and 87 % (95 % CI: 76 %-93 %) in 8 studies, respectively. For polyps ≥ 10 mm, the pooled estimates for sensitivities and specificities were 87 % (95 % CI: 83 %-90 %) and 95 % (95 % CI: 92 %-97 %) in 9 studies, respectively. A patients' perspective was assessed in 31 % (n = 4) of studies, and no preference of CCE over OC was reported. Bowel preparation was adequate in 61 % to 92 % of CCE exams. Conclusions  CCE provides high diagnostic accuracy in an adequately cleaned large bowel. Conclusive findings on patient perspectives require further studies to increase acceptance/adherence of CCE for CRC screening.

Second-generation colon capsule endoscopy for detection of colorectal polyps: A meta-analysis

Background: Colorectal cancer counts as the third prevalent type of cancer and the fourth cause of death worldwide. The second-generation colon capsule endoscopy (CCE-2) is a new technology for the diagnosis of colon cancer. The aim of this review was to provide information on the diagnostic accuracy (diagnostic effectiveness) of the second-generation colon capsule endoscopy compared to colonoscopy for the diagnosis of colon cancer and disorders.

Methods: A systematic review of literature in PubMed, Scopus, Science Direct, and Cochrane Library and Iranian databases, such as MagIran, SID, Irandoc, the grey literature (via Google Scholar) was conducted on February 30, 2018. QUADAS-2 was used to assess the quality of the studies. MetaDiSc 2.0 software was used for the meta-analysis.

Results: In this review, 480 records were identified. Eight prospective cohort articles were included among which 7 included in the meta-analysis. For the diagnosis of colorectal polyps with a diameter of 6-10 mm, the pooled sensitivity and specificity were 84% (95% CI, 80% -88%) and 88% (95%CI, 85% -90%). For the diagnosis of 10 mm or bigger colorectal polyps, the pooled sensitivity and specificity were 84% (95% CI, 76%-89%) and 96% (95% CI, 94 %-97%). The sensitivity and specificity of the capsule in the detection of any size polyps were 93% (95% CI, 97%-84%) and 66% (95% CI, 48%-81%), respectively.

Conclusion: There is little evidence to show the accuracy of CCE-2. Nevertheless, this review showed that the second-generation colon capsule endoscopy has good accuracy in the detection of polyps and colorectal cancer among high- and middle-risk patients.

Update on Flexible Sigmoidoscopy, Computed Tomographic Colonography, and Capsule Colonoscopy

This article reviews alternative colorectal cancer (CRC) screening tests, including flexible sigmoidoscopy (FS), computed tomography (CT) colonography, and colon capsule endoscopy. FS has abundant and convincing evidence supporting its use for CRC screening and is a commonly used CRC test worldwide. CT colonography has demonstrated convincing results for CRC screening, but concerns regarding cost, accuracy for flat or sessile neoplasia, reproducibility, extracolonic findings, and lack of coverage have limited its use and development. Colon capsule endoscopy has demonstrated encouraging results for polyp detection in average-risk individuals, but is not approved for CRC screening at the current time.

Booster medication to achieve capsule excretion in colon capsule endoscopy: a randomized controlled trial of three regimens

Background and study aims  To achieve a complete colon capsule endoscopy, the entire colon must be visualized, clean and filled with clear fluids. The primary aim was to compare three booster regimens in colon capsule endoscopy in achieving capsule excretion within recording time. Secondary aims were quality of bowel cleansing and completion rate (both adequate cleansing and capsule excretion). Patients and methods  Patients scheduled for follow-up colonoscopy due to previous neoplastic findings or familial history of colorectal cancer aged 18 to 70 years were eligible. Bowel preparation was 2-L split doses of polyethylene glycol. Patients were randomized to three booster regimens of either polyethylene glycol (Group A), sulfate-based solution (Group B) or polyethylene glycol with iodine oral contrast (Group C). Results  One hundred eighty participants were included and randomized into three groups of 60. Capsule excretion was 70 % (95 % CI: 58 - 80) in Group A, 73 % (95 % CI: 61 - 83) in Group B and in 68 % (95 % CI: 56 - 79) in Group C, no statistically significant differences. Bowel cleansing grade was statistically significant better in Group B compared to Group A ( P  = 0.03), but there were no statistically significant differences between Groups C and A ( P  = 0.40). Complete examination rate was 65 % (95 % CI: 53 - 77), 72 % (95 % CI: 61 - 83) and 62 % (95 % CI: 50 - 74) in Group A, B and C respectively, not statistically significant different. Conclusions  Sulfate-based solution resulted in statistically significant better bowel cleansing compared to polyethylene glycol. Overall the excretion and completion rate was suboptimal. Achieving a high completion rate using patient-tolerable and low-risk compounds is still a challenge.

Recent Advance in Colon Capsule Endoscopy: What's New?

Colon capsule endoscopy (CCE) is a relatively new diagnostic procedure for patients with suspected colonic diseases. This convenient,noninvasive method enables the physician to explore the entire colon without significant discomfort to the patient. However, while CCEcan be performed painlessly without bowel air insufflation, the need for vigorous bowel preparation and other technical limitationsexist. Due to such limitations, CCE has not replaced conventional colonoscopy. In this review, we discuss historical and recentadvances in CCE including technical issues, ideal bowel preparation, indications and contraindications and highlight further technicaladvancements and clinical studies which are needed to develop CCE as a potential diagnostic tool.

Colon capsule endoscopy to screen for colorectal neoplasia in those with family histories of colorectal cancer

BACKGROUND AND AIMS

Colon capsule endoscopy (CCE) has been recognized as an alternative for colorectal cancer (CRC) screening in average-risk people. Our aim was to prospectively assess the accuracy of CCE as a screening tool in first-degree relatives (FDRs) of people with CRC by using optical colonoscopy (OC) with segmental unblinding as the reference standard.

METHODS

Consecutive patients admitted with a CRC diagnosis (index cases) were prospectively evaluated and invited to contact their FDRs. Available FDRs were invited to undergo CCE and OC on the following day, with segmental unblinding of CCE results. Sensitivity, specificity, and predictive values/negative predictive values (PPV/NPV) of CCE were assessed for detecting patients with any polyp ≥6 mm and ≥10 mm.

RESULTS

A total of 177 FDRs (median age 57.0 years, 54.8% female) identified from 211 index cases were included. Both CCE and OC were completed in all the included FDRs. Overall, CCE identified 51 of 56 FDRs with polyps ≥6 mm (sensitivity 91%; 95% CI, 81-96) and correctly classified as negative 107 of 121 participants without lesions ≥6 mm (specificity 88%; 95% CI, 81-93). Per-patient positive and negative predictive values for ≥6 mm lesions were 78% (95% CI, 67-87) and 95% (95% CI, 90-98), respectively. CCE detected 24 of 27 patients with polyps ≥10 mm and correctly classified as negative 142 of 150 patients, corresponding to 89% sensitivity and 95% specificity. Post-CCE referral rates to colonoscopy were 37% and 18%, respectively.

CONCLUSIONS

CCE is an accurate method to screen FDRs of patients with CRC and could be offered as an alternative to those who decline or are unfit for colonoscopy screening. (Clinical trial registration number: NCT01184781.).

The impact of hospitalization on the performance of capsule endoscopy (CE)

BACKGROUND

For proper evaluation of capsule endoscopy (CE), a complete examination is necessary.

AIM

We evaluated risk factors of an incomplete CE with focus on patient hospitalization.

METHODS

We retrospectively evaluated 161 consecutive patients who underwent CE between 01.07.2013 and 13.03.2016. Main indications were active bleeding, iron deficiency anemia (IDA), inflammatory bowel disease (IBD), abdominal pain, and familial adenomatous polyposis (FAP).

RESULTS

We report the results of 103 in-patients and 56 out-patients. Eighty-two patients were male, average age was 58.9 years (range 18-90). Indications for CE were active bleeding (103 patients), IDA and IBD (16 patients), and FAP, abdominal pain and others (eight examinations each). All FAP patients were out-patients, but showed the longest small bowel transit time (SBTT) of 443.6min (p=0.0001). The shortest SBTT was found in out-patients without FAP (267.5min, p<0.05). In the in-patient group, nine endoscopies did not record the entire small bowel (8.7%) due to battery depletion, compared with only one incomplete examination in the out-patients (1.8%, p=0.036). We found pathologic lesions in the last 30min of the SBTT in 43 patients, and this indicates the necessity for complete examination. Thirteen of these 43 patients showed major lesions such as ulcers or angiodysplasia in this last region alone.

CONCLUSION

In-patients might require special treatment to ensure complete examination, since a considerable amount of pathologies can only be found in the ileum.

Colon capsule endoscopy: toward the future

Colon capsule endoscopy is a wireless and minimally invasive technique for visualization of the whole colon. With recent improvements of technical features in second-generation systems, a more important role for colon capsule endoscopy is rapidly emerging. Although several limitations and drawbacks are yet to be resolved, its usefulness as a tool for colorectal cancer screening and monitoring disease activity in inflammatory bowel diseases has become more apparent with increased use. Further investigations, including multicenter trials, are required to evaluate the substantial role of the colon capsule in managing colorectal diseases.

Clinical Practice Guidelines for the Use of Video Capsule Endoscopy

BACKGROUND & AIMS

Video capsule endoscopy (CE) provides a noninvasive option to assess the small intestine, but its use with respect to endoscopic procedures and cross-sectional imaging varies widely. The aim of this consensus was to provide guidance on the appropriate use of CE in clinical practice.

METHODS

A systematic literature search identified studies on the use of CE in patients with Crohn's disease, celiac disease, gastrointestinal bleeding, and anemia. The quality of evidence and strength of recommendations were rated using the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

The consensus includes 21 statements focused on the use of small-bowel CE and colon capsule endoscopy. CE was recommended for patients with suspected, known, or relapsed Crohn's disease when ileocolonoscopy and imaging studies were negative if it was imperative to know whether active Crohn's disease was present in the small bowel. It was not recommended in patients with chronic abdominal pain or diarrhea, in whom there was no evidence of abnormal biomarkers typically associated with Crohn's disease. CE was recommended to assess patients with celiac disease who have unexplained symptoms despite appropriate treatment, but not to make the diagnosis. In patients with overt gastrointestinal bleeding, and negative findings on esophagogastroduodenoscopy and colonoscopy, CE should be performed as soon as possible. CE was recommended only in selected patients with unexplained, mild, chronic iron-deficiency anemia. CE was suggested for surveillance in patients with polyposis syndromes or other small-bowel cancers, who required small-bowel studies. Colon capsule endoscopy should not be substituted routinely for colonoscopy. Patients should be made aware of the potential risks of CE including a failed procedure, capsule retention, or a missed lesion. Finally, standardized criteria for training and reporting in CE should be defined.

CONCLUSIONS

CE generally should be considered a complementary test in patients with gastrointestinal bleeding, Crohn's disease, or celiac disease, who have had negative or inconclusive endoscopic or imaging studies.

Colon Capsule Endoscopy: Review and Perspectives

Colon capsule endoscopy utilizing PillCam COLON 2 capsule allows for visualization potentially of the entire colon and is currently approved for patients who cannot withstand the rigors of traditional optical colonoscopy (OC) and associated sedation as well as those that had an OC that was incomplete for technical reasons other than a poor preparation. We will then describe the prior experience and current status of colon capsule endoscopy.

Evaluation of the clinical efficacy of colon capsule endoscopy in the detection of lesions of the colon: prospective, multicenter, open study

BACKGROUND

Colon capsule endoscopy (CCE) is a new procedure for colon imaging. Limited information is available regarding visualization of flat colon lesions and patient acceptability in Japan.

OBJECTIVE

The aims of this study were to evaluate the sensitivity of CCE in detecting polyps and other lesions compared with optical colonoscopy (OC) and to evaluate its safety and acceptability in a cohort of Japanese patients.

DESIGN

A prospective, open-label, clinical study in Japan.

SETTING

Multicenter.

PATIENTS

Patients referred for OC because of personal history of polyps ≥6 mm or any other colon lesion that required endoscopic or surgical treatment.

INTERVENTIONS

CCE followed by therapeutic colonoscopy.

MAIN OUTCOME MEASUREMENTS

The primary endpoint was per-patient sensitivity of CCE in detecting significant colon lesion. The secondary endpoints were CCE safety and patient acceptability.

RESULTS

Sixty-six of the 72 patients enrolled in the study were evaluated for efficacy. The per-patient sensitivity was 94% (95% confidence interval [CI], 88.2%-99.7%). The per-polyp sensitivity was 86.6% (95% CI, 81.3%-91.9%) when pathology-confirmed polyps were considered true positives. There were no adverse events related to CCE, and the acceptability of CCE was high.

LIMITATIONS

All patients had previously confirmed colon lesions, which may have falsely elevated the sensitivity of CCE.

CONCLUSION

CCE had a high sensitivity for detecting significant colon lesions. CCE was safe and had a high level of patient acceptability. (

CLINICAL TRIAL REGISTRATION NUMBER

University Hospital Medical Information Network, UMIN000007258.).

Polyethylene glycol plus an oral sulfate solution as a bowel cleansing regimen for colon capsule endoscopy: a prospective, single-arm study in healthy volunteers

OBJECTIVES

As with colonoscopy, adequate bowel cleansing is essential prior to colon capsule endoscopy (CCE). Because CCE requires that the capsule traverse the entire gastrointestinal tract during the examination, laxative 'boosters' are used. The objective of this prospective, single-center, single-arm study was to evaluate the safety of a bowel preparation consisting of polyethylene glycol (PEG) plus an oral sulfate solution.

METHODS

Subjects were healthy volunteers aged 50-75 years old with normal baseline serum chemistry. The bowel preparation consisted of 4 Senna tablets, 4 liters of PEG (split dose), 10 mg metoclopramide, 2 oral sulfate solution boosters (6 oz. and 3 oz.), and 10 mg bisacodyl. Serum chemistry was performed at baseline, following PEG intake, 24 hours after bisacodyl administration, and at 7 days post procedure (in subjects with abnormal 24 hour results). The primary endpoints were the percentage of subjects with a clinically significant change in serum chemistry at the last test and the adverse event (AE) rate.

RESULTS

A total of 25 subjects were enrolled. The serum chemistry was normal in all subjects at the final evaluation. One subject showed a slight elevation in creatinine (1.08 mg/dl 7 days post procedure from 0.84 mg/dl at baseline), deemed not clinically significant. Another subject had a transient elevation in serum creatinine (from 1.01 mg/dl at baseline to 1.45 mg/dl at 24 hours after the bowel preparation); values returned to near baseline at 7 days post procedure (1.06 mg/dl). There were no serious AEs, three moderate AEs related to the bowel preparation (nausea, headache, elevated creatinine) and two mild unrelated AEs (chills, abdominal cramping).

CONCLUSIONS

A bowel cleansing regimen of PEG plus an oral sulfate solution can be used in healthy volunteers. These data provide support for the continued study of this regimen in future CCE clinical trials and in medical practice.

Breath testing as potential colorectal cancer screening tool

Although colorectal cancer (CRC) screening is included in organized programs of many countries worldwide, there is still a place for better screening tools. In this study, 418 breath samples were collected from 65 patients with CRC, 22 with advanced or nonadvanced adenomas, and 122 control cases. All patients, including the controls, had undergone colonoscopy. The samples were analysed with two different techniques. The first technique relied on gas chromatography coupled with mass spectrometry (GC-MS) for identification and quantification of volatile organic compounds (VOCs). The T-test was used to identify significant VOCs (p values < 0.017). The second technique relied on sensor analysis with a pattern recognition method for building a breath pattern to identify different groups. Blind analysis or leave-one-out cross validation was conducted for validation. The GC-MS analysis revealed four significant VOCs that identified the tested groups; these were acetone and ethyl acetate (higher in CRC), ethanol and 4-methyl octane (lower in CRC). The sensor-analysis distinguished CRC from the control group with 85% sensitivity, 94% specificity and 91% accuracy. The performance of the sensors in identifying the advanced adenoma group from the non-advanced adenomas was 88% sensitivity, 100% specificity, and 94% accuracy. The performance of the sensors in identifying the advanced adenoma group was distinguished from the control group was 100% sensitivity, 88% specificity, and 94% accuracy. For summary, volatile marker testing by using sensor analysis is a promising noninvasive approach for CRC screening.

Colon Capsule Endoscopy for the Detection of Colorectal Polyps: An Evidence-Based Analysis

BACKGROUND

Colorectal cancer, a leading cause of mortality and morbidity in Ontario, can be prevented through early diagnosis and removal of precancerous polyps. Colon capsule endoscopy is a relatively new, minimally invasive test for detecting colorectal polyps.

OBJECTIVE

The objectives of this analysis were to evaluate the diagnostic accuracy and safety of colon capsule endoscopy for the detection of colorectal polyps among adult patients with signs or symptoms of colorectal cancer or with increased risk of colorectal cancer, and to compare colon capsule endoscopy with alternative procedures.

REVIEW METHODS

A literature search was performed using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid EMBASE, the Wiley Cochrane Library, and the Centre for Reviews and Dissemination database, for studies published between 2006 and 2014. Data on diagnostic accuracy and safety were abstracted from included studies. Quality of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE).

RESULTS

The search yielded 2,189 citations. Five studies, all of which evaluated PillCam COLON 2 (PCC2), met the inclusion criteria. The per-patient sensitivity and specificity for detecting colorectal polyps were meta-analyzed. Colon capsule endoscopy, using PCC2, had a pooled sensitivity and specificity of 87% (95% confidence interval [CI] 77%-93%) and 76% (95% CI 60%-87%), respectively, for the detection of a colorectal polyp at least 6 mm in size (GRADE: very low). PCC2 had a pooled sensitivity and specificity of 89% (95% CI 77%-95%) and 91% (95% CI 86%-95%), respectively, for the detection of a colorectal polyp at least 10 mm in size (GRADE: low). One study directly compared PCC2 with computed tomographic (CT) colonography and found no statistically significant difference in accuracy (GRADE: low). Few adverse events were reported with PCC2; 3.9% of patients (95% CI 2.4%-6.5%) experienced adverse effects related to bowel preparation. Capsule retention was the most serious adverse event and occurred in 0.8% of patients (95% CI 0.2%-2.4%) (GRADE: very low).

CONCLUSIONS

In adult patients with signs, symptoms, or increased risk of colorectal cancer, there is low-quality evidence that colon capsule endoscopy using the PCC2 device has good sensitivity and specificity for detecting colorectal polyps. Low-quality evidence does not show a difference in accuracy between colon capsule endoscopy and CT colonography. There is very low-quality evidence that PCC2 has a good safety profile with few adverse events; capsule retention is the most serious complication.

Colon Capsule Endoscopy for the Detection of Colorectal Polyps: An Economic Analysis

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.

Colon capsule endoscopy

Colon capsule endoscopy (CCE) is a minimally invasive technique specifically designed to explore the colon without sedation and air insufflation. CCE may overcome some of the limitations of colonoscopy. Second-generation CCE (CCE-2) was proved accurate in detecting colonic neoplastic lesions when used in average-risk individuals. The evidence to date supports the use of CCE-2 in cases of colonoscopy failure, in patients unwilling to undergo colonoscopy, and when colonoscopy is contraindicated. Other potential applications, such as colorectal cancer screening or diagnostic surveillance of inflammatory bowel disease, require clarification.

Capsule Endoscopy in the Assessment of Obscure Gastrointestinal Bleeding: An Economic Analysis

BACKGROUND

Small-bowel capsule endoscopy is a tool used to visualize the small bowel to identify the location of bleeds in obscure gastrointestinal bleeding (OGIB). Capsule endoscopy is currently funded in Ontario in cases where there has been a failure to identify a source of bleeding via conventional diagnostic procedures. In Ontario, capsule endoscopy is a diagnostic option for patients whose findings on esophagogastroduodenoscopy, colonoscopy, and push enteroscopy have been negative (i.e., the source of bleeding was not found).

OBJECTIVES

This economic analysis aims to estimate the budget impact of different rates of capsule endoscopy use as a complement to push enteroscopy procedures in patients aged 18 years and older.

DATA SOURCES

Population-based administrative databases for Ontario were used to identify patients receiving push enteroscopy and small-bowel capsule endoscopy in the fiscal years 2008 to 2012.

REVIEW METHODS

A systematic literature search was performed to identify economic evaluations of capsule endoscopy for the investigation of OGIB. Studies were assessed for their methodological quality and their applicability to the Ontarian setting. An original budget impact analysis was performed using data from Ontarian administrative sources and published literature. The budget impact was estimated for different levels of use of capsule endoscopy as a complement to push enteroscopy due to the uncertain clinical utility of the capsule based on current clinical evidence. The analysis was conducted from the provincial public payer perspective.

RESULTS

With varying rates of capsule endoscopy use, the budgetary impact spans from savings of $510,000, when no (0%) push enteroscopy procedures are complemented with capsule endoscopy, to $2,036,000, when all (100%) push enteroscopy procedures are complemented with capsule endoscopy. A scenario where 50% of push enteroscopy procedures are complemented with capsule endoscopy (expected use based on expert opinion) would result in additional expenditure of about $763,000.

LIMITATIONS

In the literature on OGIB, estimates of rebleeding rates after endoscopic procedures or spontaneous cessation rates are unreliable, with a lack of data. Rough estimates from expert consultation can provide an indication of expected additional use of capsule endoscopy; however, a wide range of capsule uses was explored.

CONCLUSIONS

The budgetary impact in the first year in Ontario of capsule endoscopy use to complement push enteroscopy procedures ranges from $510,000 in savings to an additional expenditure of $2,036,000 (at 0% and 100% push enteroscopy procedures complemented, respectively). The expected scenario of 50% of push enteroscopy procedures likely to benefit from the use of capsule endoscopy, based on expert opinion, would result in additional expenditures of $763,000 in the first year.

Wireless capsule endoscopy of the large intestine: a review with future projections

PURPOSE OF REVIEW

Video capsule endoscopy, which was initially developed for exploring the small bowel, has been adapted for investigating the colon. This review summarizes recent developments in colon capsule technology as well as indications for its use.

RECENT FINDINGS

Second-generation PillCam colon capsule endoscopy (CCE-2) has been recently developed and has significantly improved the sensitivity and specificity of colon capsules for detecting polyps and/or tumors in patients with suspected or known colonic lesions. The use of CCE-2 has been shown to be of value in patients with incomplete standard colonoscopy. The use of CCE-2 has also been investigated in patients with ulcerative colitis and in outpatient settings. Several trials have tried to simplify the colon preparation regimen.

SUMMARY

Colon capsule endoscopy is a novel technique for exploring the colon. CCE-2 has improved the diagnostic capability of this noninvasive method. There is still room for improvement and simplification of colon preparation regimens. Apart from detection of polyps or neoplasms, colon capsule endoscopy has also been assessed in patients with inflammatory bowel disease.