Chromoscopy versus conventional endoscopy for the detection of polyps in the colon and rectum

Comparative Evaluation of Colon Cancer Specific Antigen-2 Test and Chromocolonoscopy for Early Detection of Egyptian Patients with Colorectal Cancer

Background: Effective screening of colorectal cancer (CRC) in early stage could reduce the advancement of CRC and therefore mortality. Effective screening is based on either stool dependent tests or colon dependent examination.

Aims: The aim of the study was a comparative evaluation of chromocolonoscopy and Colon Cancer-Specific Antigen-2 test for early detection of colorectal cancer in Egyptian patients.

Methods: This case control study was carried out on 55 patients classified into 3 groups: Group I consisted of twenty patients with precancerous lesions detected by colonoscopy, Group II consisted of twenty patients diagnosed with colorectal cancer and Group III consisted of fifteen individuals (who underwent colonoscopy for other indications) as a control group. All the subjects were subjected to measure occult blood in the stool, measurement of Colon Cancer-Specific Antigen-2 level in serum and tissue and chromo colonoscopy using Indigo Carmine stain.

Results: In group II, there was a statistically significant increase in CCSA2 in serum as compared to the other 2 groups. Cutoff >11.3 CCSA2 in serum showed 65% sensitivity, 85% specificity, 81.2% PPV, 70.8% NPV and 70.3% accuracy in the differentiation of group II with cancer colon from group I with premalignant colonic lesions. A cutoff > 9.1 CCSA2 in serum showed 95% sensitivity, 46.67% specificity, 70.4% PPV, 87.5% NPV and 73.5% accuracy in differentiating group II with cancer colon from normal controls (group III).

Conclusion: CCSA-2 level in serum was significantly higher in cancer colon. Chromoendoscopy has a role in the detection of polyps, both neoplastic and non-neoplastic.

Impact of Hyoscine Bromide Use on Polyp Detection Rate During Colonoscopy: A Systematic Review and Meta-Analysis

Background

Colorectal cancer (CRC) is a leading cause of death worldwide. Polyp detection rate (PDR) and adenoma detection rate (ADR) are key focus in endoscopic research for CRC screening and prevention. Use of anti-spasmodic agents during colonoscopy to help identify adenomas and polyps has remained a controversial topic. Hyoscine butyl bromide (HBB) is the most commonly used anti-spasmodic agent in patients undergoing colonoscopy. Some randomized controlled trials (RCTs) have questioned the clinical efficacy and safety of routine use of HBB for polyp and adenoma detection rates.

Methods

We conducted a systematic search in PubMed and MEDLINE from inception until February 10, 2018, for studies which compared HBB with placebo. We used RevMan version 5.3 for analysis. Procedural end-points were polyps, adenomas, and advanced adenoma detection rates, mean number of polyps detected and cecal intubation time.

Results

We included seven RCTs with 2,588 patients in our analysis. A total of 1,301 patients were randomized to HBB arm and 1,287 to the placebo arm. There was no significant difference in the primary outcome of polyp detection rate, 654 in HBB group vs. 616 in the placebo group, (odds ratio (OR) = 1.11, confidence interval (CI) = 0.93 - 1.34, P = 0.25). There was no difference in secondary outcomes of adenoma detection rate, 430 in HBB group vs. 396 in the placebo group, (OR = 1.06, CI = 0.89 - 1.26, P = 0.51), advanced adenoma detection rate, 92 in HBB vs. 95 in placebo group (OR = 0.95, CI = 0.70 - 1.30, P = 0.76), mean number of polyps detected (point estimate = 0.12, CI = 0.00 - 0.23, P = 0.05), adenomatous polyps (OR = 0.84, CI = 0.39 - 1.81, P = 0.65) and cecal intubation time (point estimate = 0.73, CI = -1.98 - 0.52, P = 0.25) between the two groups.

Conclusions

The use of HBB in patients undergoing colonoscopy does not appear to improve polyp or adenoma detection rates. It showed a non-significant trend of increased mean number of polyps detected with HBB.

Efficacy of Endocuff-assisted colonoscopy in the detection of colorectal polyps

BACKGROUND AND STUDY AIMS

Colonoscopy is the gold standard for detecting colorectal adenomas and cancers. Endoscopic surveillance has been shown to be effective for preventing colorectal cancer. Although detection of colorectal polyps at an early stage is important, endoscopic visualization of early neoplasia can be difficult. The Endocuff is a new device that can be attached to the tip of the colonoscope to hold the colonic folds away from the field of view during withdrawal. The aim of this study was to compare the adenoma detection rate (ADR) and the mean number of adenomas detected per patient (MAP) achieved using Endocuff-assisted colonoscopy (EAC) and standard colonoscopy (SC).

PATIENTS AND METHODS

This randomized prospective study was conducted at two academic endoscopy departments in Japan. A total of 447 patients underwent a complete colonoscopic examination between April 2015 and September 2015. The EAC group included 239 patients. The cecal intubation rate, insertion time, withdrawal time, pain score, complications, polyp detection rate (PDR), ADR, the mean number of polyps detected per patient (MPP), and the MAP were assessed.

RESULTS

There were no differences between the EAC and SC groups in terms of cecal intubation rate, insertion time, withdrawal time, or pain scores. The PDR in patients increased by about 12 % (61.9 % vs. 49.2 %, P  = 0.013) and ADR increased by 15 % (52.5 % vs. 39.2 %, P  = 0.001) with the use of the Endocuff. The advanced ADR was higher in the EAC group but no statistically significant difference was found (7.7 % vs. 4.6 %, P  = 0.17). Both MPP and MAP were also higher in the EAC group (mean ± SD: 1.33 ± 1.43 vs. 0.83 ± 0.99 per patient; P  < 0.01, 1.11 ± 1.41 vs. 0.66 ± 0.99 per patient; P  < 0.01, respectively). No major complications occurred.

CONCLUSIONS

 EAC not only enabled a higher ADR but also significantly increased the mean number of adenomas identified per patient, as compared with SC.

Microscopic imaging in endoscopy: endomicroscopy and endocytoscopy

Performing real-time microscopy has been a vision of endoscopists since the very early phases of gastrointestinal endoscopy. Confocal endomicroscopy, an adaption of confocal laser scanning microscopy, and endocytoscopy, an adaption of white-light microscopy, have been introduced into the endoscopic armamentarium in the past decade. Both techniques yield on-site histological information. Multiple trials have demonstrated the ability of gastroenterologists to obtain and interpret microscopic images from the upper and lower gastrointestinal tract, and also the hepatobiliary-pancreatic system, during endoscopy. Such microscopic information has been successfully used in expert hands to minimize sampling error by 'smart', microscopically targeted biopsies and to guide endoscopic interventions. However, endomicroscopy is also unique in its ability to dynamically visualize cellular processes in their native environment free of artefacts. This ability enables fundamental insights into mechanisms of human diseases in clinical and translational science.

i-Scan high-definition white light endoscopy and colorectal polyps: prediction of histology, interobserver and intraobserver agreement

PURPOSE

Aim of the study was the evaluation of high-definition white light (HDWL) i-Scan endoscopy for diagnostic prediction of histology, inter- and intraobserver agreement for colorectal polyps.

METHODS

In this prospective single-center cohort study, a skilled endoscopist, with HDWL i-Scan, predicted on real-time the histology of 150 polyps from 78 patients undergoing colonoscopy. Subsequently, four endoscopists, not involved in the collection of cases, predicted the polyps' histology (neoplastic vs nonneoplastic) and repeated the assessment after 6 months.

RESULTS

Real-time assessment of the lesions predicted a correct histology in 138/150 cases with a sensitivity, specificity, and accuracy of 95, 82, and 92 %, respectively. Sensitivity, specificity, and accuracy of post-acquisition evaluation were 87.7, 61.7, and 82.2 %, respectively. The κ values of inter- and intraobserver agreement of prediction of histology were 0.462 (0.373-0.537) and 0.657 (0.523-0.917). Among the subset of polyps (n = 82) with good/excellent quality image, sensitivity and accuracy of HDWL i-Scan improved (97 %, p = 0.003 and 94 %, p = 0.002, respectively) as well as κ value of interobserver agreement (0.699).

CONCLUSIONS

HDWL i-Scan technology helps for characterization of polyps of the colon with good accuracy even if it cannot replace, at the moment, the histopathological examination. Reproducibility among operators is supported by a moderate substantial interobserver and intraobserver agreement.