Dataset Information

Impact of Proximal Colon Retroflexion in Colorectal Cancer Screening Programme

ABSTRACT: Colorectal cancer (CRC) is the most common tumor and the second leading cause of death in the Western world. The decrease in incidence and mortality by CRC in the population undergoing screening has been observed. Colonoscopy is the recommended method for detecting tumors in early stages, as well as identifying and resecting adenomatous polyps, which are the precursor lesions of most CRCs. Colonoscopy should be of high quality to decrease incidence and mortality by CRC and avoid interval cancer. The literature shows that colonoscopy does not prevent right colon lesions in the same way as the left colon lesions, with most of the interval cancers located in the right colon. Studies published so far show an increase in the adenomas detection rate (ADT) in the right colon in the second visualization of this segment and an increase between 2 and 10% if this second examination is performed with the proximal retroflexion maneuver.Retroflexion is a safe maneuver in expert endoscopists. The aim of our study is to evaluate the ADT in the right colon by means of a second visualization by performing proximal retroflexion or second frontal visualization at random in the CCR screening population.

DISEASE(S): Adenoma Detection Rate,Colorectal Neoplasms,Adenoma

PROVIDER: 2235806 | ecrin-mdr-crc |

REPOSITORIES: ECRIN MDR

ACCESS DATA

Similar Datasets

Project description:It is estimated that there are about 1.4 million patients with colorectal cancer (CRC) worldwide, with a rising trend in CRC incidence in many Asian Pacific countries. In Hong Kong, colorectal cancer ranks first in cancer incidence and second in cancer mortality based on data from 2013. CRC is one of the most preventable cancers because its development in general follows an adenoma-carcinoma sequence. Adenomas are considered precursor lesions for CRC. While early detection and removal of colorectal adenoma by screening colonoscopy with polypectomy reduce CRC incidence and mortality, interval cancers (cancers that develop after a colonoscopy and before the next scheduled colonoscopy) may still occur and were reported to account for up to 10.5% of CRC. The protective effect of colonoscopy against cancer in the right colon has not been consistently demonstrated. Interval CRC has been associated with proximal colon location, small lesion, flat lesion, missed lesion, inadequate examination, incomplete resection of lesion, tumor biology, and low adenoma detection rate (ADR). High ADR (eg, ≥ 20%) has been associated with a reduced risk of interval CRC. Methods that can improve polyp detection in the right colon such as retroflexed examination of the right colon, second forward view examination of the right colon, use of colonic fold flattening device, colonoscope with an increased field of view may potentially reduce the risk of interval CRC, but data is still limited. Performance of a second forward view (SFV) examination of the right colon may be the easiest and safest from a practical standpoint when compared to other options (eg, additional training is often needed for retroflexed examination of the right colon since there may be a potentially higher risk of perforation in endoscopists not familiar with the technique, additional equipment is needed when using a colonic fold flattening device, or a colonoscope with an increased field of view). Our current study aims to determine whether a routine SFV examination in the right colon can lead to an increase in adenoma / polyp detection when compared to conventional withdrawal examination in the right colon in both male and female patients undergoing screening and surveillance colonoscopies.

Project description:The degree of protection afforded by colonoscopy against proximal colorectal cancer (CRC) appears to be related to the quality of the procedure, and the incomplete removal of lesions has been shown to increase the subsequent risk of developing a colon cancer. Some studies suggest that small polyps with advanced histology are more common in the right than in the left colon (right colon proximal to splenic flexure, left colon distal to the splenic flexure). The average size of polyps in the right colon with advanced pathology or containing adenocarcinoma was ≤9 mm, whereas in the left colon their average size was >9 mm, P<0.001. Inadequate prevention of right-sided CRC incidence and mortality may be due to right-sided polyps with advanced histology or that harbor malignancy. These presumptive precursors of cancer are smaller and possibly more easily obscured by residual feces, and more likely to be missed at colonoscopy. Water-aided colonoscopy (WAC) can be subdivided broadly into two major categories: water immersion (WI), characterized by suction removal of the infused water predominantly during the withdrawal phase of colonoscopy, and water exchange (WE), characterized by suction removal of infused water predominantly during the insertion phase of colonoscopy. In some reports WE appeared to be superior to both WI and air insufflation colonoscopy (AI) in terms of pain reduction and adenoma detection, particularly for <10 mm adenomas in the proximal colon. In this multicenter, double-blinded randomized controlled trial (RCT) we test the hypothesis that that WE, compared to AI and WI, will enhance overall Adenoma Detection Rate (ADR) in CRC screening patients. Confirmation of the primary hypothesis will provide evidence that WE enhances the quality of screening colonoscopy. We also hypothesize that WE may be more effective in detecting proximal colon adenomas than WI and AI, particularly <10 mm adenomas, thus increasing proximal colon ADR and proximal colon ADR <10 mm. Confirmation of secondary hypotheses will provide justification for further testing that WE may provide a strategy to improve prevention of colorectal cancer by increasing detection of adenomas in screening colonoscopy. Unlike previous reports of single colonoscopist studies, the insertion and withdrawal phases of colonoscopy will be done by different investigators. The second investigator will be blinded to the method used to insert the instrument, thus eliminating possible bias about procedure related issues. Several secondary outcomes will also be analysed.

Dataset Information

Impact of Proximal Colon Retroflexion in Colorectal Cancer Screening Programme

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets