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

Prospective study of diagnostic yields of flexible spectral imaging color enhancement installed in colon capsule endoscopy for colorectal polyps and tumors

BACKGROUND AND AIMS

We prospectively determined the efficacy of flexible spectral imaging color enhancement (FICE) used with second-generation colon capsule endoscopy (CCE) for colorectal polyps and tumors (CRTs).

METHODS

This study included optical colonoscopy within 4 months after CCE. Two colonoscopists independently reviewed CCE using white-light images (CCE-WL) and CCE using FICE images (CCE-FICE), respectively. Based on colonoscopic findings as the criterion standard, the diagnostic accuracy for CRTs was compared between CCE-WL and CCE-FICE.

RESULTS

Of 89 enrolled patients (65 men and 24 women; 75 with CRTs including 36 with serrated lesions, 63 with adenomas, and 9 with adenocarcinomas), the per-patient detectability of CCE-FICE for the representative CRTs was significantly higher than that of CCE-WL: overall CRTs (CCE-WL, 79%; CCE-FICE, 88%; P = .0001), 6- to 9-mm CRTs (CCE-WL, 63%; CCE-FICE, 94%; P = .0055), and ≥6-mm CRTs (CCE-WL, 78%; CCE-FICE, 93%; P = .0159). The per-lesion sensitivity of CCE-FICE was significantly higher than that of CCE-WL for CRTs: overall (CCE-WL, 61%; CCE-FICE, 79%; P < .0001), <6 mm (CCE-WL, 53%; CCE-FICE, 69%; P < .0001), 6- to 9-mm CRTs (CCE-WL, 65%; CCE-FICE, 93%; P = .0007), slightly elevated CRTs (CCE-WL, 53%; CCE-FICE, 75%; P < .0001), tubular adenomas (CCE-WL, 61%; CCE-FICE, 79%; P < .0001), and serrated polyps (CCE-WL, 57%; CCE-FICE, 74%; P = .0022). Both modes detected all adenocarcinomas. No significant differences were found between CCE-WL and CCE-FICE of the per-lesion sensitivity for ≥10-mm CRTs (CCE-WL, 81%; CCE-FICE, 94%; P = .1138) or protruding CRTs (CCE-WL, 77%; CCE-FICE, 86%; P = .0614). Kappa coefficients for overall CRTs for CCE-WL and CCE-FICE were .66 and .64, respectively, which indicated substantial agreement.

CONCLUSIONS

CCE-FICE improved the detection rates for all CRTs except adenocarcinomas, ≥10-mm polyps, and protruding polyps when compared with CCE-WL. (Clinical trial registration number: UMIN 000021125.).

Delays in Colorectal Cancer Screening for Latino Patients: The Role of Immigrant Healthcare in Stemming the Rising Global Incidence of Colorectal Cancer

The significant global burden of colorectal cancer accentuates disparities in access to preventive healthcare in most low- and middle-income countries (LMICs) as well as large sections of underserved populations within high-income countries. The barriers to colorectal cancer screening in economically transitioning Latin America are multiple. At the same time, immigration from these countries to the USA continues to increase. This case highlights the delays in diagnosis experienced by a recent immigrant from a country with no established colorectal cancer screening program, to an immigrant population in the USA with similar poor screening coverage. We discuss common challenges faced by Latinos in their home countries and the USA, as well as strategies that could be implemented to improve screening coverage in US immigrant 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.

Performance of radiographic imaging after incomplete colonoscopy for nonmalignant causes in clinical practice

BACKGROUND AND AIMS

CT colonography (CTC) or barium enema are commonly ordered to complete colorectal imaging after an incomplete colonoscopy. We evaluated the sensitivity of radiographic studies performed for this purpose in clinical practice outside clinical trials.

METHODS

Adult patients referred to an expert endoscopist for incomplete colonoscopy because of a redundant colon or a difficult sigmoid and who underwent previous radiographic imaging between July 2001 and July 2019 were identified. None of the patients had a malignant obstruction as the cause of incomplete colonoscopy. Data on polyp size, location, and pathology were obtained from colonoscopy and radiology reports. Polyps identified on imaging and colonoscopy were matched based on polyp size and location.

RESULTS

Among 769 patients referred for incomplete colonoscopy, we identified 65 with a radiographic examination performed within 36 months of colonoscopy at our center. Per-patient sensitivity for CTC was suboptimal (70%) and was very low for barium enema (26.7%). Per-polyp sensitivity for both CTC and barium enema was poor (23.8% and 7.6%). Quality of the examination did not seem to affect procedure sensitivity.

CONCLUSIONS

Radiographic imaging after incomplete colonoscopy for reasons other than malignant obstruction had poor sensitivity for polyps. Patients with incomplete colonoscopies should be considered for repeat colonoscopy by an expert.

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.

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.

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.