Second-generation colon capsule endoscopy compared with colonoscopy

Multicenter feasibility study of bowel preparation with castor oil for colon capsule endoscopy

BACKGROUND AND AIM

Extensive use of laxatives and incomplete excretion rates are problematic for colon capsule endoscopy (CCE). The aim of the present study was to determine the effectiveness of castor oil as a booster.

METHODS

At four Japanese hospitals, 319 examinees undergoing CCE were enrolled retrospectively. Before and after the introduction of castor oil, other preparation reagents were unchanged.

RESULTS

Of 319 examinees who underwent CCE, 152 and 167 examinees took regimens with castor oil (between November 2013 and June 2016) and without castor oil (between October 2015 and September 2017), respectively. Capsule excretion rates within its battery life in the groups with and without castor oil were 97% and 81%, respectively (P < 0.0001). Multivariate analysis showed that ages younger than 65 years (adjusted odds ratio [OR], 3.00; P = 0.0048), male gender (adjusted OR, 3.20; P = 0.0051), and use of castor oil (adjusted OR, 6.29; P = 0.0003) were predictors of capsule excretion within its battery life. Small bowel transit time was shorter and total volume of lavage and fluid intake was lower with castor oil than without (P = 0.0154 and 0.0013, respectively). Overall adequate cleansing level ratios with and without castor oil were 74% and 83%, respectively (P = 0.0713). Per-examinee sensitivity for polyps ≥6 mm with and without castor oil was 83% and 85%, respectively, with specificities of 80% and 78%, respectively.

CONCLUSION

Bowel preparation with castor oil was effective for improving capsule excretion rate and reducing liquid loading.

Establishment of a Novel Scoring System for Colon Capsule Endoscopy to Assess the Severity of Ulcerative Colitis-Capsule Scoring of Ulcerative Colitis

BACKGROUND

The usefulness of second-generation colon capsule endoscopy (CCE-2) for ulcerative colitis (UC) has not been fully demonstrated. This study aimed to develop an endoscopic severity score of UC for CCE-2.

METHODS

Patients diagnosed with UC were enrolled prospectively and underwent colonoscopy and CCE-2 on the same day. The collected CCE-2 videos were adopted for the development of the score. These videos were scored by 4 blinded inflammatory bowel disease experts. The items validated with the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) were used as the candidate items, some of which were automatically assessed using the workstation. Each item was divided into proximal and distal parts at the splenic flexure and then individually assessed. The image readers simultaneously evaluated the inflammation severity using the visual analog scale (VAS). The descriptors that contribute to this scale were evaluated, and a model to predict the VAS was constructed. The UCEIS was scored by other endoscopists using colonoscopy videos. The correlation coefficients with fecal calprotectin, blood tests, and Lichtiger index were calculated.

RESULTS

The final scoring system was fixed as "vascular pattern sum (proximal + distal) + bleeding sum + erosions and ulcers sum (minimum-maximum, 0-14)" and was named Capsule Scoring of Ulcerative Colitis (CSUC). The correlation coefficient of CSUC with biomarkers and clinical score was similar to that of the UCEIS.

CONCLUSIONS

We developed a new simple score using the 3 descriptors of CCE-2.

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.

Capsule endoscopy vs. colonoscopy vs. histopathology in colorectal cancer screening: matched analyses of polyp size, morphology, and location estimates

PURPOSE

Colon capsule endoscopy (CCE) is considered a potential alternative to optical colonoscopy (OC) for colorectal cancer screening. However, the accuracy of CCE in polyp size and morphology estimation is unknown.

METHODS

A fully paired study was performed (2015-2016), where 255 participants from the Danish national screening program had CCE, OC, and histopathology (HP) of all detected polyps. We developed a new algorithm to match CCE and OC polyps, based on objective measures of similarity between polyps. We performed paired comparisons of size, morphology and location of CCE, and OC- and HP-matched polyps. We used cross-validation to develop a model able to predict HP polyp size, based on CCE.

RESULTS

CCE overestimated size assessed by HP (by 4.3 mm; 95%CI 3.3-5.2 mm) and OC (by 2.7 mm; 95%CI 1.4-3.9 mm). Polyps were more likely to being assessed as "pedunculated" and less likely to being assessed as "flat" in CCE, compared to OC (p < 0.0001). Our model could predict HP polyp size ≥ 6 mm, solely using CCE-assessed size, location, and morphology as model inputs, with a sensitivity = 0.93 (95%CI 0.66-1.00) and specificity = 0.50 (95%CI 0.32-0.68).

CONCLUSIONS

If CCE is to be used as a screening test, it is essential: (1) to translate CCE polyp estimations into histopathologic polyp sizes and (2) to consider that, compared to OC, CCE has a higher tendency to assess polyps as pedunculated and a lower tendency to assess them as flat.

TRIAL REGISTRATION

Clinicaltrials.gov No. NCT02303756.

PillCamColon2 after incomplete colonoscopy - A prospective multicenter study

AIM

To evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy (OC) and to assess the diagnostic yield.

METHODS

This prospective multicentre study included 81 patients from nine centres who underwent second-generation colon capsule endoscopy (CCE) following incomplete OC performed by an experienced gastroenterologist (> 1000 colonoscopies). Patients with stenosis were excluded. According to patient preferences, CCE was performed the following day (protocol A) after staying on clear liquids and 0.75 L Moviprep in the morning or within 30 d after new split-dose Moviprep (protocol B). Boosts consisted of 0.75 L and 0.25 L Moviprep, and phospho-soda was given as a rescue if the capsule was not excreted after seven hours.

RESULTS

Seventy-four patients were analysed (51% of them in group A; 49% in group B). Bowel cleansing was adequate in 67% of cases, and CCE could visualize colonic segments missed by incomplete colonoscopy in 90% of patients under protocol A and 97% of patients under protocol B (P = 0.35, n.s.). Significant polyps including adenocarcinoma were detected in 24% of cases. Detection rates for all polyps and significant polyps per patient were similar in both protocols. Polyps were found predominantly in the right colon (86%) in segments that were not reached by OC. Extracolonic findings - such as reflux esophagitis, suspected Barrett esophagus, upper GI-bleeding, gastric polyps, gastric erosions and angiectasia - were detected in eight patients. PillCamColon2 capsule was retained in the ileum of one patient (1.4%) without symptoms and removed during an uneventful resection for unknown Crohn’s disease that was diagnosed as the cause of anemia, which was the indication for colonoscopy. CCE was well tolerated. One patient suffered from self-limiting vomiting after consuming the phospho-soda.

CONCLUSION

Second-generation CCE using a low-volume preparation is useful after incomplete OC, and it allows for the detection of additional relevant findings, but cleansing efficiency could be improved.

Association of clinical and inflammatory markers with small bowel capsule endoscopy findings in Crohn's disease

BACKGROUND

Mucosal healing is an established treatment endpoint in Crohn's disease (CD). Still, clinical indices and inflammatory markers are used widely in CD surveillance.

AIM

The aim of this study was to investigate the diagnostic performance as well as the relationship of C-reactive protein (CRP) and Crohn's Disease Activity Index (CDAI) with small bowel capsule endoscopy's (SBCE) inflammation scoring index, the Lewis Score (LS).

PATIENTS AND METHODS

CDAI, CRP, and SBCE findings of 30 CD patients with isolated small bowel disease were retrieved from our academic institution patient records and were analyzed statistically.

RESULTS

SBCE showed significant mucosal inflammation [mean (SD) LS: 1599 (1380)], in nine (60.0%) of 15 patients who were in both clinical and biochemical remission. CDAI and CRP showed a weak and moderate correlation with LS (r=0.317, P=0.088 and r=0.516, P=0.004, respectively). The diagnostic performance of CDAI and CRP in predicting mucosal inflammation was as follows: sensitivity 23.8 and 52.4%; specificity 100 and 66.7%; positive predictive value 100 and 78.6%; and negative predictive value 36.0 and 37.5%. The area under the curve toward endoscopic activity prediction was 0.70 and 0.69, respectively.

CONCLUSION

Both CDAI and CRP underestimated endoscopic activity as expressed by the LS in a significant proportion of patients with quiescent disease.

Development of a computed cleansing score to assess quality of bowel preparation in colon capsule endoscopy

BACKGROUND AND STUDY AIMS

Colon capsule endoscopy (CCE) does not possess an objective and reliable scoring system to assess the quality of visualization of the colon mucosa. The aim of this study was to establish a colonic computed assessment of cleansing (CAC) score able to discriminate "adequately cleansed" from "inadequately cleansed" CCE still frames.

PATIENTS AND METHODS

Twelve normal and complete CCEs, using the Pillcam Colon 2 system (Medtronic, Minnesota, United States), were prospectively selected amongst a database. A CAC score, defined as the ratio of color intensities red over green (R/G ratio), and red over brown (R/(R + G) ratio) was calculated for each extracted colonic frame. After sorting and random selection, two sets of still frames representative of the range of these ratios were obtained. These images were analyzed twice in random order by two experienced CCE readers who were blinded to the CAC scores. A receiver operating characteristic (ROC) curve was forged for both types of ratios and a threshold established, yielding the highest diagnostic performance in terms of adequate cleansing assessment.

RESULTS

Four-hundred-and-eight frames were extracted. Regarding the R/G ratio, a threshold value of 1.55 was calculated, with a sensitivity of 86.5 % and a specificity of 77.7 %. Regarding the R/(R + G) ratio, a threshold value of 0.58 was calculated with a sensitivity of 95.5 % and a specificity of 62.9 %.

CONCLUSION

 The two proposed CAC scores based on the ratio of color intensities come with high sensitivities for discriminating between "adequately cleansed" and "inadequately cleansed" CCE still frames, but they lack specificity. Further refinement, with implementation of additional image parameters, is warranted.

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.).

Multicenter, randomized study to optimize bowel preparation for colon capsule endoscopy

AIM

To assess the cleansing efficacy and safety of a new Colon capsule endoscopy (CCE) bowel preparation regimen.

METHODS

This was a multicenter, prospective, randomized, controlled study comparing two CCE regimens. Subjects were asymptomatic and average risk for colorectal cancer. The second generation CCE system (PillCam^® COLON 2; Medtronic, Yoqneam, Israel) was utilized. Preparation regimens differed in the 1^st and 2^nd boosts with the Study regimen using oral sulfate solution (89 mL) with diatrizoate meglumine and diatrizoate sodium solution (“diatrizoate solution”) (boost 1 = 60 mL, boost 2 = 30 mL) and the Control regimen oral sulfate solution (89 mL) alone. The primary outcome was overall and segmental colon cleansing. Secondary outcomes included safety, polyp detection, colonic transit, CCE completion and capsule excretion ≤ 12 h.

RESULTS

Both regimens had similar cleansing efficacy for the whole colon (Adequate: Study = 75.9%, Control = 77.3%; P = 0.88) and individual segments. In the Study group, CCE completion was superior (Study = 90.9%, Control = 76.9%; P = 0.048) and colonic transit was more often < 40 min (Study = 21.8%, Control = 4%; P = 0.0073). More Study regimen subjects experienced adverse events (Study = 19.4%, Control = 3.4%; P = 0.0061), and this difference did not appear related to diatrizoate solution. Adverse events were primarily gastrointestinal in nature and no serious adverse events related either to the bowel preparation regimen or the capsule were observed. There was a trend toward higher polyp detection with the Study regimen, but this did not achieve statistical significance for any size category. Mean transit time through the entire gastrointestinal tract, from ingestion to excretion, was shorter with the Study regimen while mean colonic transit times were similar for both study groups.

CONCLUSION

A CCE bowel preparation regimen using oral sulfate solution and diatrizoate solution as a boost agent is effective, safe, and achieved superior CCE completion.

Systematic review and meta-analysis: is bowel preparation still necessary in small bowel capsule endoscopy?

INTRODUCTION

Optimal bowel preparation for small bowel capsule endoscopy(SBCE) is controversial. This meta-analysis aimed to investigate the effects of laxatives in SBCE.

METHODS

A comprehensive literature search was conducted for studies investigating the use of laxatives in SBCE. The primary outcome was diagnostic yield(DY) for SB findings; secondary outcomes SB visualization quality(SBVQ) and completion rate(CR). Pooled odds ratios(ORs) with 95% confidence intervals(CIs) and number needed to treat(NNT) were calculated.

RESULTS

Forty studies (4380 patients with laxatives, 2185 without) were included. Laxative use did not improve DY of SB findings overall (OR 1.11 (95%CI 0.85-1.44)) or for significant SB findings (OR 1.10 (95%CI 0.76-1.60)). However, SBVQ improved with the use of laxatives (OR 1.60 (95%CI 1.08-2.06)), NNT 14. The OR for completed SBCE was 1.30 (95%CI 0.95-1.78). Patients given polyethylene glycol(PEG) had lower DY than sodium phosphate(NaP). SBVQ improved more with NaP (NNT 7) than PEG (NNT 53).

CONCLUSIONS

Laxatives do not significantly improve DY or CR in SBCE, but do improve SBQV. The use of laxatives may be beneficial in patients likely to have subtle findings. There are significant differences in methodology/definitions between studies, hence the need for standardized visualization scoring and recording of SBCE findings.

Diagnostic capability of colon capsule endoscopy for advanced colorectal cancer: A pilot study

BACKGROUND AND AIM

Colon capsule endoscopy (CCE) is a safe and effective method for detecting lesions in the colon. However, the sensitivity of CCE in detecting advanced colorectal cancer (CRC) has not been sufficiently evaluated. Therefore, the aim of the present study was to assess the sensitivity of CCE in detecting advanced CRC.

METHODS

Patients previously diagnosed with advanced CRC by conventional colonoscopy underwent CCE. Primary outcome measure was the sensitivity of CCE in detecting advanced CRC per patient and per lesion. Secondary parameters measured were the sensitivity of CCE in detecting polyps ≥6 mm and ≥10 mm in size in a per-lesion analysis and the safety of CCE.

RESULTS

Of the 21 advanced CRC lesions in 20 patients, 17 were detected by CCE. The per-patient and per-lesion sensitivities of CCE for detecting advanced CRC lesions were 85% (95% confidence interval [CI]: 62-97%) and 81% (95% CI: 58-95%), respectively. All advanced CRC lesions were diagnosed in the accessible region by CCE while the capsule was still functional. A significant association was found between incomplete CCE and failure to diagnose advanced CRC. No severe adverse events occurred.

CONCLUSION

The diagnostic capability of CCE in detecting advanced CRC was limited in cases of procedure incompletion. Refining procedures to increase CCE procedure completion rates are required to enhance CRC detection.

Feasibility of a novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy

Bowel preparation regimens for colon capsule endoscopy are not yet standardized since they are not well optimized. The aim of the present study was to evaluate the feasibility of a novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy. A total of 31 patients were prospectively enrolled. In the novel regimen, on the day prior to examination, a low-fiber diet was permitted, 5 mg mosapride citrate was administered twice (1 h prior to lunch and supper) and 1 l polyethylene glycol was administered in the evening. On the day of the examination, an additional 1 l polyethylene glycol, 5 mg mosapride citrate and 200 mg simethicone were administered before capsule ingestion. Polyethylene glycol booster (0.5 l) was administered twice, at 1 and 4 h following capsule ingestion. Colon cleansing levels, ileocecal valve transit time and completion rate were evaluated. A total of 29 patients were included in the final analysis, 90% of whom achieved adequate preparation of the overall colon. Ileocecal valve transit time was 2.35±0.82 h and completion rate was 79.3%. The results revealed that the novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy was feasible, with adequate colon cleansing and completion rates, and has the potential to be used as an alternative regimen.

Where do I see minimally invasive endoscopy in 2020: clock is ticking

Since it was introduced 17 years ago, capsule endoscopy has become an important diagnostic tool for the small bowel. Three generations of the original small bowel capsule have been developed since (PillCam SB3, Medtronic, USA), and four competitors were introduced for the small bowel. A non-video patency capsule (Agile patency capsule, Medtronic, USA) was also developed, in order to confirm patency and thus avoid retention in the GI tract. Moreover, capsules viewing other organs of the body (esophagus, colon) as well as three different magnetic guided capsules that visualize the stomach as good as optical endoscopy (OE) have been developed. Over 2,000 articles looking at the efficacy of the small bowel capsule in different clinical situations were published since then. Studies are comparing capsule endoscopy versus other modalities in various indications, looking at preparations aiming to improve the diagnostic yield and at technical aspects. The present paper, describes the available capsules in the market and my biased future expectations.

Evaluation for the Clinical Efficacy of Colon Capsule Endoscopy in the Detection of Laterally Spreading Tumors

BACKGROUND AND AIM

The manner in which colorectal lesions are being detected with PillCam COLON2 capsule endoscopy (CCE2) has markedly improved in recent days. However, limited data are available on CCE2 for detecting laterally spreading tumors (LSTs). The aim of this study was to compare CCE2 with optical colonoscopy (OC), which is currently the gold standard used in the detection of LSTs.

METHODS

We performed a prospective, single-academic center study comparing CCE2 with OC in patients with LSTs diagnosed using OC, which was performed during the 3-month period prior to CCE2. We focused on the sensitivity and specificity of CCE2 for detecting LSTs. LSTs were classified into the LST-granular type (LST-G) or the LST-non-granular type (LST-NG).

RESULTS

Thirty patients (mean age 59.5 years) were enrolled. Of them, 21 LSTs (7 LST-Gs and 14 LST-NGs) were evaluated in this study. The mean diameter of the LSTs was 27 ± 15 mm (range 10-60 mm). Histopathological diagnoses of the LSTs were as follows: tubular adenoma, 12 cases (57%); sessile serrated adenoma/polyp (SSA/P), 4 cases (19%); Tis carcinoma, 1 case (5%); and T1 carcinoma, 4 cases (19 LSTs were found in the following locations: cecum, 1 case (5%); ascending colon, 6 cases (29%); transverse colon, 6 cases, (29%); descending colon, 1 case (5%); sigmoid colon, 3 cases (13%); and rectum, 4 cases (19%). The colon cleansing level was adequate in all cases. The sensitivity and specificity of CCE2 for detecting LSTs were 81 and 100% respectively. For detecting LST-Gs and LST-NGs, the sensitivity and specificity were 71 and 100%, and 86 and 100%, respectively. There were 4 false-negative cases (LST-G (18 mm), cecum; LST-G (20 mm), sigmoid colon; LST-NG (25 mm), transverse colon; LST-NG (20 mm), transverse colon).

CONCLUSIONS

The sensitivity for detecting LSTs is lower with CCE2 than it is with OC, especially for LSTs located on the right colon or for SSA/P.

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.

Guideline for wireless capsule endoscopy in children and adolescents: A consensus document by the SEGHNP (Spanish Society for Pediatric Gastroenterology, Hepatology, and Nutrition) and the SEPD (Spanish Society for Digestive Diseases)

INTRODUCTION

Capsule Endoscopy (CE) in children has limitations based mainly on age. The objective of this consensus was reviewing the scientific evidence.

MATERIAL AND METHODS

Some experts from the Spanish Society of Gastroenterology (SEPD) and Spanish Society for Pediatric Gastroenterology, Hepatology, and Nutrition (SEGHNP) were invited to answer different issues about CE in children. These sections were: a) Indications, contraindications and limitations; b) efficacy of CE in different clinical scenarios; c) CE performance; d) CE-related complications; e) Patency Capsule; and f) colon capsule endoscopy. They reviewed relevant questions on each topic.

RESULTS

The main indication is Crohn's disease (CD). There is no contraindication for the age and in the event that the patient not to swallow it, it should be administered under deep sedation with endoscopy and specific device. The CE is useful in CD, for the management of OGIB in children and in Peutz-Jeghers syndrome (in this indication has the most effectiveness). The main complication is retention, which should be specially taken into account in cases of CD already diagnosed with malnutrition. A preparation regimen based on a low volume of polyethylene glycol (PEG) the day before plus simethicone on the same day is the best one in terms of cleanliness although does not improve the results of the CE procedure.

CONCLUSIONS

CE is safe and useful in children. Indications are similar to those of adults, the main one is CD to establish both a diagnosis and disease extension. Moreover, only few limitations are detected in children.

Prospective study of factors important to achieve observation of the entire colon on colon capsule endoscopy

BACKGROUND

Colon capsule endoscopy (CCE) is a procedure in which capsule swallowing facilitates observation of the lumen of the entire digestive tract. It does not require an air supply, and is a noninvasive procedure with a markedly low risk of adverse events in comparison with conventional colonoscopy (CS). It reduces patient stress, and may be acceptable to patients. A limitation of this procedure is that the entire colon observation rate (CCE excretion rate, completed CCE rate) is not 100%. In this study, we prospectively investigated clinical factors important to achieve observation of the entire colon on CCE.

METHODS

The participants were 70 patients for whom CCE was scheduled, and from whom written informed consent regarding participation in this study was obtained. We selected patient background/examination factors, and analyzed all factors involved in observation of the entire colon and factors for completion of the CCE within 4 h after the start of examination using multivariate analysis.

RESULTS

Of the 70 enrolled patients, 64 were analyzed, excluding 6. On multiple logistic analysis, only a water intake of ⩾12.0 ml/min during examination [p = 0.025, odds ratio (OR): 46.753, 95% confidence interval (CI): 1.630-1341.248] was identified as an independent predictive factor involved in observation of the entire colon. With respect to factors involved in the completion of CCE within 4 h, multiple logistic analysis showed that a body mass index (BMI) of ⩾25 (p = 0.039, OR: 13.723, 95% CI: 1.135-165.913), the absence of constipation (p = 0.030, OR: 13.988, 95% CI: 1.287-152.047), and a water intake of ⩾12.0 ml/min during examination (p = 0.004, OR: 12.028, 95% CI: 2.225-65.029) were independent predictive factors.

CONCLUSIONS

Completion of a CCE was most closely related to water intake per hour. In addition to water intake, CCE-promoting factors included a high BMI and the absence of constipation.

Polyp Detection and Segmentation from Video Capsule Endoscopy: A Review

Video capsule endoscopy (VCE) is used widely nowadays for visualizing the gastrointestinal (GI) tract. Capsule endoscopy exams are prescribed usually as an additional monitoring mechanism and can help in identifying polyps, bleeding, etc. To analyze the large scale video data produced by VCE exams, automatic image processing, computer vision, and learning algorithms are required. Recently, automatic polyp detection algorithms have been proposed with various degrees of success. Though polyp detection in colonoscopy and other traditional endoscopy procedure based images is becoming a mature field, due to its unique imaging characteristics, detecting polyps automatically in VCE is a hard problem. We review different polyp detection approaches for VCE imagery and provide systematic analysis with challenges faced by standard image processing and computer vision methods.

Sensitivity of 2-[18F]fluoro-2-deoxyglucose positron emission tomography for advanced colorectal neoplasms: a large-scale analysis of 7505 asymptomatic screening individuals

BACKGROUND

The sensitivity of 2-[¹⁸F]fluoro-2-deoxyglucose positron emission tomography (FDG-PET) for advanced colorectal neoplasms among healthy subjects is not yet fully understood. The present study aimed to clarify the sensitivity by analyzing large-scale data from an asymptomatic screening population.

METHODS

A total of 7505 asymptomatic screenees who underwent both FDG-PET and colonoscopy at our Cancer Screening Division between February 2004 and March 2013 were analyzed. FDG-PET and colonoscopy were performed on consecutive days, and each examination was interpreted in a blinded fashion. The results of the two examinations were compared for each of the divided six colonic segments, with those from colonoscopy being set as the reference. The relationships between the sensitivity of FDG-PET and clinicopathological features of advanced neoplasms were also evaluated.

RESULTS

Two hundred ninety-one advanced neoplasms, including 24 invasive cancers, were detected in 262 individuals. Thirteen advanced neoplasms (advanced adenomas) were excluded from the analysis because of the coexistence of lesions in the same colonic segment. The sensitivity, specificity, and positive and negative predictive values of FDG-PET for advanced neoplasms were 16.9 % [95 % confidence interval (CI) 12.7-21.8 %], 99.3 % (95 % CI 99.2-99.4 %), 13.5 % (95 % CI 10.1-17.6 %), and 99.4 % (95 % CI 99.3-99.5 %), respectively. The sensitivity was lower for lesions with less advanced histological grade, of smaller size, and flat-type morphology, and for those located in the proximal part of the colon.

CONCLUSIONS

FDG-PET is believed to be difficult to use as a primary screening tool in population-based colorectal cancer screening because of its low sensitivity for advanced neoplasms. Even when it is used in opportunistic cancer screening, the limit of its sensitivity should be considered.

Accuracy of First- and Second-Generation Colon Capsules in Endoscopic Detection of Colorectal Polyps: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Colon capsule endoscopy (CCE) is a noninvasive technique used to explore the colon without sedation or air insufflation. A second-generation capsule was recently developed to improve accuracy of detection, and clinical use has expanded globally. We performed a systematic review and meta-analysis to assess the accuracy of CCE in detecting colorectal polyps.

METHODS

We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and other databases from 1966 through 2015 for studies that compared accuracy of colonoscopy with histologic evaluation with CCE. The risk of bias within each study was ascertained according to Quality Assessment of Diagnostic Accuracy in Systematic Reviews recommendations. Per-patient accuracy values were calculated for polyps, overall and for first-generation (CCE-1) and second-generation (CCE-2) capsules. We analyzed data by using forest plots, the I² statistic to calculate heterogeneity, and meta-regression analyses.

RESULTS

Fourteen studies provided data from 2420 patients (1128 for CCE-1 and 1292 for CCE-2). CCE-2 and CCE-1 detected polyps >6 mm with 86% sensitivity (95% confidence interval [CI], 82%-89%) and 58% sensitivity (95% CI, 44%-70%), respectively, and 88.1% specificity (95% CI, 74.2%-95.0%) and 85.7% specificity (95% CI, 80.2%-90.0%), respectively. CCE-2 and CCE-1 detected polyps >10 mm with 87% sensitivity (95% CI, 81%-91%) and 54% sensitivity (95% CI, 29%-77%), respectively, and 95.3% specificity (95% CI, 91.5%-97.5%) and 97.4% specificity (95% CI, 96.0%-98.3%), respectively. CCE-2 identified all 11 invasive cancers detected by colonoscopy.

CONCLUSIONS

The sensitivity in detection of polyps >6 mm and >10 mm increased substantially between development of first-generation and second-generation colon capsules. High specificity values for detection of polyps by CCE-2 seem to be achievable with a 10-mm cutoff and in a screening setting.

Extracolonic findings with the PillCam Colon: is panendoscopy with capsule endoscopy closer?

Background and study aims: Colon capsules display images from the moment they are ingested, making the study of other extracolonic areas possible. The aim of this study was to analyze the significance of these extracolonic findings. Patients and methods: In this single-center, prospective study, 165 patients underwent colon capsule endoscopy (CCE) between September 2009 and October 2012 to rule out colonic pathology. Images were recorded, without interruptions, from the moment the capsule was ingested until its battery ran out. The study was deemed complete when the capsule had traveled from the esophagus to excretion or until the hemorrhoidal plexus was observed. Results: CCE was used for colorectal cancer (CRC) screening (81.2 %), to investigate for chronic diarrhea (9.7 %) and chronic iron deficiency anemia (6.1 %), and for patients with incomplete colonoscopy (3.0 %). The capsule returned findings in the esophagus in 52.1 % of patients, in the stomach in 45.5 % of patients, and in the small bowel in 70.7 % of patients, with the findings being considered relevant in 4.9 %, 9.7 %, and 22.6 % of patients, respectively. The whole extent of the digestive tract was fully recorded in 86.1 % of patients and the Z line could be fully observed in 57.6 % of patients. There were no adverse events. Conclusions: CCE allows the recording of images from almost the whole extent of the digestive tract in most patients, enabling relevant pathologies to be identified in extracolonic areas, particularly the small bowel. Technical and procedural improvements are still necessary in order to achieve better observation of the stomach and esophagus.

PillCam colon capsule endoscopy (PCCE) in colonic diseases

Diseases affecting the colon are common worldwide and can cause a major health problem. Colorectal cancer (CRC) as well as Inflammatory bowel diseases represent a major cause of morbidity and mortality in western countries. PillCam colon capsule endoscopy (PCCE) is a novel and promising technology that can be useful for the screening and monitoring of colonic diseases. In the recent years many articles examined the use of various versions of PCCE-the 1st and 2nd generation versus various other endoscopic or radiologic modalities both for detection of colonic polyps or cancer and in both ulcerative colitis (UC) and Crohn's disease. The aim of the current review is to provide up to date information regarding the use and usefulness of this method in these disease.

Colon Capsule Endoscopy: Where Are We and Where Are We Going

Colon capsule endoscopy (CCE) is a noninvasive technique for diagnostic imaging of the colon. It does not require air inflation or sedation and allows minimally invasive and painless colonic evaluation. The role of CCE is rapidly evolving; for example, for colorectal screening (colorectal cancer [CRC]) in average-risk patients, in patients with an incomplete colonoscopy, in patients refusing a conventional colonoscopy, and in patients with contraindications for conventional colonoscopy. In this paper, we comprehensively review the technical characteristics and procedure of CCE and compare CCE with conventional methods such as conventional colonoscopy or computed tomographic colonography. Future expansion of CCE in the area of CRC screening for the surveillance of polyps and adenomatous lesions and for assessment of inflammatory bowel disease is also discussed.

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 performance of the Omni mode for detecting video capsule endoscopy images: A multicenter randomized controlled trial

BACKGROUND AND STUDY AIMS

Olympus recently developed a new algorithm called Omni mode that discards redundant video capsule endoscopy (VCE) images. The current study aimed to demonstrate the non-inferiority of the Omni mode in terms of true positives (TPs) and the superiority of the Omni mode with regard to reading time against a control (ordinary ES-10 system).

PATIENTS AND METHODS

This multicenter prospective study included 40 patients with various small bowel diseases. VCE images were evaluated by 7 readers and 3 judging committee members. Two randomly allocated readers assessed the VCE images obtained using the 2 modalities for each patient. The order of the modalities was switched between the 2 readers and the interval between readings by the same reader was 2 weeks. The judging committee predefined clinically relevant lesions as major lesions and irrelevant lesions as minor lesions. The number of TPs for major and minor lesions and the reading times were compared between the modalities. The predefined non-inferiority margin for the TP ratio of the Omni mode compared with the control was 0.9.

RESULTS

The estimated TP ratios and 95 % confidence intervals for total, major, and minor lesions were 0.87 (0.80 - 0.95), 0.93 (0.83 - 1.04), and 0.83 (0.74 - 0.94), respectively. Although non-inferiority was not demonstrated, the rate of detection of major lesions was not significantly different between the modalities. The reading time was significantly lower when using the Omni mode than when using the control.

CONCLUSIONS

The Omni mode may be only appropriate for the assessment of major lesions.

The role of small bowel capsule endoscopy and ileocolonoscopy in patients with nonspecific but suggestive symptoms of Crohn's disease

OBJECTIVES

Ileocolonoscopy (IC) and small bowel capsule endoscopy (SBCE) are essential tools in the investigation of suspected small bowel Crohn's disease (CD). Overutilization of SBCE should be avoided as it leads to unwanted healthcare expenses; thus, it is recommended when IC is normal and CD is still highly suspected. Our aim was to compare the role of SBCE and IC in the investigation of suspected CD irrespective of its location and assess the additional diagnostic benefit of SBCE over IC.

METHODS

This was a retrospective study of 91 patients with chronic abdominal pain and/or diarrhea. All patients were evaluated with both colonoscopy (with terminal ileum intubation where possible) and SBCE. The severity of inflammation on SBCE was assessed using the Lewis Score. Endoscopic findings were analyzed toward CD diagnosis.

RESULTS

The sensitivity of IC and SBCE in the diagnosis of either small bowel or colonic CD was 81.82 and 63.64%, whereas the specificity was 77.50 and 92.50%, respectively. Positive and negative predictive value was 33.33 and 96.88% for IC, as well as 53.85 and 94.87% for SBCE. Area under receiver operating characteristic curve was 0.797 for IC and 0.781 for SBCE. IC was superior to SBCE in diagnosing small and large bowel CD. SBCE showed the true extent of CD in one patient missed by IC. It identified lesions suggestive of CD in three patients with normal IC, one of whom was finally diagnosed with CD.

CONCLUSION

IC should be the initial diagnostic test in patients with nonspecific, but suggestive symptoms of CD. SBCE offers additional information on small bowel mucosa and disease extent.

Diagnostics and Epidemiology of Colorectal Cancer

Colorectal cancer is one of the leading causes of cancer-related morbidity and mortality. Main risk factors include advanced age, family history, male sex, and lifestyle factors. Screening can reduce incidence and death from colorectal cancer. Therefore, prevention and early detection are crucial in order to detect and remove pre-neoplastic adenomas and to detect cancers at early stages. Colonoscopy, flexible sigmoidoscopy, and fecal occult blood tests are established tools for screening. Newer fecal immunochemical tests reveal higher sensitivities for advanced adenoma and cancer than guaiac-based hemoccult tests. Molecular stool and blood tests as well as virtual colonoscopy and colon capsule endoscopy are promising new developments so far not established as routine instruments for the prevention and early detection of colorectal cancer. Colonoscopy is the method of choice for the diagnosis of colorectal cancer and for adenoma removal. Prognosis is essentially dependent on the tumor stage at the time of the initial diagnosis. Proper staging based on imaging prior to therapy is a prerequisite. In rectal cancer, local staging is an essential requirement for the identification of appropriate candidates for neoadjuvant therapy.

Initial US evaluation of second-generation capsule colonoscopy for detecting colon polyps

Objectives

Capsule colonoscopy is an additional screening modality for colorectal cancer. Second-generation capsule colonoscopy (CC2) may have improved efficacy in the detection of colon adenomas as compared with prior devices. The purpose of this study was to evaluate the performance of CC2 in the detection of polyps in symptomatic and screening patients in the USA.

Design

Prospective, multicentre study.

Setting and participants

Two academic medical centres and two private practice facilities, evaluating patients with indications for colonoscopy.

Methods

Patients underwent capsule colonoscopy procedure using magnesium citrate as a boost, followed by colonoscopy on the same day. The main outcome measurement was accuracy of CC2 for the detection of colorectal polyps ≥6 and ≥10 mm as compared with conventional colonoscopy.

Results

51 patients were enrolled, 50 of whom had CC2 and colonoscopy examinations and were included in the accuracy analysis. 30% and 14% of patients had polyps ≥6 and ≥10 mm, respectively. For lesions ≥10 mm identified on conventional colonoscopy, CC2 sensitivity was 100% (95% CI 56.1% to 100%) with a specificity of 93.0% (79.9% to 98.2%). For polyps ≥6 mm, the CC2 sensitivity was 93.3% (66.0% to 99.7%) and the specificity was 80.0% (62.5% to 90.9%). There was a 61% adequate cleansing rate with 64% of CC2 procedures being complete.

Conclusions

In the initial US experience with CC2 there was adequate sensitivity for detecting patients with polyps ≥6 mm in size. Magnesium citrate was inadequate as a boost agent.

Trial registration number

NCT01087528.

Diagnostic Role of Colon Capsule Endoscopy in Patients with Optimal Colon Cleaning

Background. Colon capsule endoscopy (CCE) is a diagnostic test with relatively rare usage. In this study, we aimed to evaluate both the optimal cleaning regimen for CCE and the diagnostic value of test in the study group. Methods. A total of 62 patients were enrolled in this study. In the first step, 3 different colon preparing regimens were given to 30 patients [Group A: 3 days of liquid diet, sodium phosphate (NaP) (90 mL), and NaP enema; Group B: 3 days of liquid diet, 4 L of polyethylene glycol (PEG), and metoclopramide; Group C: 3 days of liquid diet, 4 L of PEG, NaP (45 mL), and bisacodyl after capsule ingestion] (10 patients in each group). The other consecutive 32 patients were cleaned with the best regimen which was NaP + PEG and CCE was performed. The results of CCE were controlled with colonoscopy in 28 patients. Results. Group C had the highest cleaning score, compared with the other groups (2.2 ± 0.4 versus 2.7 ± 0.4 versus 3.7 ± 0.4, p value = 0.000). The CCE findings were as follows in 28 patients who were also examined with colonoscopy: polyp (range: 5-10 mm) in 6 patients, internal hemorrhoids in 3 patients, angiodysplasia in 1 patient, diverticula in 1 patient, and ulcerative colitis in 1 patient. The sensitivity, specificity, PPV, and NPV of CCE were 100%, 92%, 93%, and 100%, respectively. Conclusions. Low dosage NaP combined with PEG provides optimal bowel preparation for CCE. CCE appears to be a highly sensitive diagnostic modality for detecting colonic pathologies.

Challenges and Future of Wireless Capsule Endoscopy

In 2015, capsule endoscopy was introduced as the main investigation method for small bowel mucosal diseases, and its role in colonic diseases has been gradually revealed. Future challenges for capsule endoscopy, besides improvements of image quality and visualization of each part of the small bowel and colonic mucosa, include the development of gastric capsules, the capacity to perform histological examination of the mucosa, and maybe in the future, some capsule endoscopy-driven therapeutics. The aim of this review was to evaluate the clinical demands and feasibility of achieving the aforementioned objectives.

Current Status and Research into Overcoming Limitations of Capsule Endoscopy

Endoscopic investigation has a critical role in the diagnosis and treatment of gastrointestinal (GI) diseases. Since 2001, capsule endoscopy (CE) has been available for small-bowel exploration and is under continuous development. During the past decade, CE has achieved impressive improvements in areas such as miniaturization, resolution, and battery life. As a result, CE is currently a first-line tool for the investigation of the small bowel in obscure gastrointestinal bleeding and is a useful alternative to wired enteroscopy. Nevertheless, CE still has several limitations, such as incomplete examination and limited diagnostic and therapeutic capabilities. To resolve these problems, many groups have suggested several models (e.g., controlled CO2 insufflation system, magnetic navigation system, mobile robotic platform, tagging and biopsy equipment, and targeted drug-delivery system), which are in development. In the near future, new technological advances will improve the capabilities of CE and broaden its spectrum of applications not only for the small bowel but also for the colon, stomach, and esophagus. The purpose of this review is to introduce the current status of CE and to review the ongoing development of solutions to address its limitations.

How does tolerability of double balloon enteroscopy compare to other forms of endoscopy?

BACKGROUND AND AIMS

Gastrointestinal endoscopy can be difficult for patients to tolerate. Studies on endoscopic tolerability mainly focus on gastroscopy or colonoscopy with a paucity of data on double balloon enteroscopy (DBE). We aimed to prospectively evaluate tolerability in patients undergoing several forms of endoscopy including DBE.

METHODS

Consecutive patients undergoing colonoscopy, flexible sigmoidoscopy, gastroscopy, endoscopic retrograde pancreatography (ERCP), capsule endoscopy (CE) and DBE were prospectively recruited. A questionnaire recorded demographics, procedural data, patient tolerability (pain, discomfort and distress recorded on numerical rating scales) and the Hospital Anxiety and Depression Scale (HADS).

RESULTS

956 patients were recruited (512 women; median age 57 years). The median pain score for DBE was poor with a score of 5 compared with 1 and 0 for oesophagogastroduodenoscopy and ERCP, respectively (p<0.001). Colonoscopy and retrograde DBE scores were not dissimilar. CE was well tolerated with a median pain score of 0. Patients with DBE required significantly higher doses of sedation and analgesia than other patients. The HADS Anxiety Score was also associated with poorer tolerability.

CONCLUSIONS

DBE is poorly tolerated when compared with other forms of endoscopy despite higher doses of sedation. Increasing demand to improve tolerability of DBE in the UK may be addressed with the use of propofol.

Uptake of Colon Capsule Endoscopy vs Colonoscopy for Screening Relatives of Patients With Colorectal Cancer

BACKGROUND & AIMS

The efficacy of screening colonoscopy in first-degree relatives (FDRs) of patients with colorectal cancer (CRC) is limited by suboptimal uptake. We compared screening uptake of colon capsule endoscopy (CCE) vs colonoscopy in this population.

METHODS

We performed a prospective study of 329 asymptomatic FDRs of patients with CRC who were randomly assigned to groups examined by CCE (PillCam, second generation; n = 165) or colonoscopy (n = 164) at a tertiary hospital in Spain from July 2012 through December 2013. Crossover was permitted for patients who did not wish to undergo the assigned procedure. Subjects assigned to CCE who had a significant lesion (polyp ≥ 10 mm, >2 polyps of any size, or CRC) were invited to undergo colonoscopy.

RESULTS

One hundred twenty subjects in the CCE group and 113 in the colonoscopy group were eligible for inclusion. In the intention-to-screen analysis, uptake was similar between groups (55.8% CCE vs 52.2% colonoscopy; odds ratio [OR], 0.86; 95% confidence interval [CI], 0.51-1.44; P = .57); 57.4% of subjects crossed over from the CCE group, and 30.2% crossed over from the colonoscopy group (OR, 3.11; 95% CI, 1.51-6.41; P = .002). Unwillingness to repeat bowel preparation in the case of a positive result was the main reason that subjects assigned to the CCE group crossed over; fear of colonoscopy was the reason that most patients in this group crossed over. A significant lesion was detected in 14 subjects (11.7%) in the CCE group and 13 subjects (11.5%) in the colonoscopy group (OR, 1.02; 95% CI, 0.45-2.26; P = .96).

CONCLUSIONS

In a prospective study, similar numbers of FDRs of patients with CRC assigned to undergo CCE or colonoscopy agreed to participate, but most preferred to undergo colonoscopy. CCE was as effective as colonoscopy in detecting significant lesions; it could be a valid rescue strategy for subjects who reject screening colonoscopy. ClinicalTrials.gov number: NCT01557101.

Colorectal cancer

Colorectal cancer had a low incidence several decades ago. However, it has become a predominant cancer and now accounts for approximately 10% of cancer-related mortality in western countries. The 'rise' of colorectal cancer in developed countries can be attributed to the increasingly ageing population, unfavourable modern dietary habits and an increase in risk factors, such as smoking, low physical exercise and obesity. New treatments for primary and metastatic colorectal cancer have emerged, providing additional options for patients; these treatments include laparoscopic surgery for primary disease, more-aggressive resection of metastatic disease (such as liver and pulmonary metastases), radiotherapy for rectal cancer, and neoadjuvant and palliative chemotherapies. However, these new treatment options have had limited impact on cure rates and long-term survival. For these reasons, and the recognition that colorectal cancer is long preceded by a polypoid precursor, screening programmes have gained momentum. This Primer provides an overview of the current state of the art of knowledge on the epidemiology and mechanisms of colorectal cancer, as well as on diagnosis and treatment.

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.).

Developments in Screening Tests and Strategies for Colorectal Cancer

BACKGROUND

Worldwide, colorectal cancer (CRC) is the third most common cancer in men and second most common in women. It is the fourth most common cause of cancer mortality. In the United States, CRC is the third most common cause of cancer and second most common cause of cancer mortality. Incidence and mortality rates have steadily fallen, primarily due to widespread screening.

METHODS

We conducted keyword searches on PubMed in four categories of CRC screening: stool, endoscopic, radiologic, and serum, as well as news searches in Medscape and Google News.

RESULTS

Colonoscopy is the gold standard for CRC screening and the most common method in the United States. Technological improvements continue to be made, including the promising "third-eye retroscope." Fecal occult blood remains widely used, particularly outside the United States. The first at-home screen, a fecal DNA screen, has also recently been approved. Radiological methods are effective but seldom used due to cost and other factors. Serum tests are largely experimental, although at least one is moving closer to market.

CONCLUSIONS

Colonoscopy is likely to remain the most popular screening modality for the immediate future, although its shortcomings will continue to spur innovation in a variety of modalities.

Controversies in colorectal cancer screening

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers worldwide and a good candidate for screening programmes. However, there is controversy concerning which of the available screening tests should be used.

SUMMARY

There is general agreement that screening for CRC in the asymptomatic population should begin at the age of 50. Several different screening methods are available which can be separated into those that mainly detect cancers: faecal occult blood tests [guaiac (FOBT) and immunochemical (FIT)], genetic stool tests, blood tests and the M2-pyruvate kinase (M2-PK) test. Methods that detect cancers and polyps are colonoscopy, sigmoidoscopy, CT-colonography (CT-C) and colon capsule endoscopy. The only tests for which a reduction in CRC mortality compared to no screening have been proven in randomized trials are FOBT and sigmoidoscopy. Several trials suggest that FIT are superior to FOBT in terms of detection rates of cancers and advanced adenomas and possibly compliance. There is indirect evidence suggesting efficacy of colonoscopy as a screening test. The role of CT-C is controversial. There is data suggesting a good sensitivity for neoplasia >9 mm with a lower sensitivity for smaller neoplasia. However, radiation exposure is considered a major limitation in some countries. Unresolved questions include the lesion cut-off for referral to colonoscopy and work-up of extracolonic findings. For other methods, like genetic stool testing using newer markers, blood tests, capsule endoscopy and M2-PK, there is currently insufficient data on screening of the asymptomatic population. Key Messages: Colorectal screening is recommended and should be performed in the form of an organized programme. If detection of early-stage cancers is the aim of a screening programme, FIT seem to be superior to FOBT. If detection and removal of adenomas is the aim of a screening programme, endoscopic methods seem to be good alternatives. Sigmoidoscopy is easier to perform but will likely only have an effect on distal cancers. Colonoscopy is more invasive but enables inspection of the whole colon. The role of CT-C, capsule endoscopy, genetic stool tests, blood tests and M2-PK is currently unknown.

Recent trends in diagnostic techniques for inflammatory bowel disease

Although ileocolonoscopy is the gold standard for diagnosis of inflammatory bowel disease and is useful for assessing the disease severity in the colon and terminal ileum, several alternative diagnostic techniques have been developed recently. For ulcerative colitis (UC), magnification colonoscopy, endocytoscopy, and confocal laser endomicroscopy enable assessment of histological inflammation without the need for biopsy. Capsule endoscopy is useful for detection of small intestinal and colonic lesions in both female and male patients. For UC, capsule endoscopy may be useful for evaluating colonic inflammation in patients with a previous poor colonoscopy experience, while it should be used only in Crohn's disease (CD) patients with unexplained symptoms when other examinations are negative. Magnetic resonance enterography (MRE) is particularly useful for detecting transmural inflammation, stenosis, and extraintestinal lesions, including abscesses and fistulas. MRE is also useful when evaluating small and large intestinal lesions, even in cases with severe strictures in which full evaluation of the small bowel would be virtually impossible using other devices. Therefore, the appropriate diagnostic devices for detecting CD lesions in the small and large intestine should be used.

Accuracy of capsule colonoscopy in detecting colorectal polyps in a screening population

BACKGROUND & AIMS

Capsule colonoscopy is a minimally invasive imaging method. We measured the accuracy of this technology in detecting polyps 6 mm or larger in an average-risk screening population.

METHODS

In a prospective study, asymptomatic subjects (n = 884) underwent capsule colonoscopy followed by conventional colonoscopy (the reference) several weeks later, with an endoscopist blinded to capsule results, at 10 centers in the United States and 6 centers in Israel from June 2011 through April 2012. An unblinded colonoscopy was performed on subjects found to have lesions 6 mm or larger by capsule but not conventional colonoscopy.

RESULTS

Among the 884 subjects enrolled, 695 (79%) were included in the analysis of capsule performance for all polyps. There were 77 exclusions (9%) for inadequate cleansing and whole-colon capsule transit time fewer than 40 minutes, 45 exclusions (5%) before capsule ingestion, 15 exclusions (2%) after ingestion and before colonoscopy, and 15 exclusions (2%) for site termination. Capsule colonoscopy identified subjects with 1 or more polyps 6 mm or larger with 81% sensitivity (95% confidence interval [CI], 77%-84%) and 93% specificity (95% CI, 91%-95%), and polyps 10 mm or larger with 80% sensitivity (95% CI, 74%-86%) and 97% specificity (95% CI, 96%-98%). Capsule colonoscopy identified subjects with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity (95% CI, 82%-93) and 82% specificity (95% CI, 80%-83%), and 10 mm or larger with 92% sensitivity (95% CI, 82%-97%) and 95% specificity (95% CI, 94%-95%). Sessile serrated polyps and hyperplastic polyps accounted for 26% and 37%, respectively, of false-negative findings from capsule analyses.

CONCLUSIONS

In an average-risk screening population, technically adequate capsule colonoscopy identified individuals with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity and 82% specificity. Capsule performance seems adequate for patients who cannot undergo colonoscopy or who had incomplete colonoscopies. Additional studies are needed to improve capsule detection of serrated lesions. Clinicaltrials.gov number: NCT01372878.