Detectability of colorectal neoplastic lesions using a narrow‐band imaging system: A pilot study

Background and Aim: Flat and depressed colorectal neoplastic lesions can be difficult to identify using conventional colonoscopy techniques. Narrow‐band imaging (NBI) provides unique views especially of mucosal vascular network and helps in visualization of neoplasia by improving contrast. The aim of this study was to assess the feasibility of using NBI for colorectal neoplasia screening. Methods: Forty‐seven consecutive patients, who underwent high definition colonoscopy (HDC) screening examinations revealing neoplastic lesions, were enrolled in our prospective study. No biopsies or resections were performed during the initial HDC, but patients in whom lesions were detected underwent further colonoscopies using NBI, with the results of the first examination blinded from the colonoscopist. They then received appropriate treatment. We compared diagnostic detection rates of neoplastic lesions for HDC and NBI procedures using total number of all identified neoplastic lesions as reference standard. Results: Altogether, 153 lesions were detected and analyzed in 43 patients. Mean diagnostic extubation times were not significantly different (P = 0.18), but the total number of lesions detected by NBI was higher (134 vs 116; P = 0.02). Based on macroscopic type, flat lesions were identified more often by NBI (P = 0.04). As for lesion size, only flat lesions < 5 mm were detected more frequently (P = 0.046). Lesions in the right colon were identified more often by NBI (P = 0.02), but NBI missed two flat lesions ≥ 10 mm located there. Conclusions: Narrow band imaging colonoscopy may represent a significant improvement in the detection of flat and diminutive lesions, but a future multi‐center controlled trial should be conducted to fully evaluate efficacy for screening colonoscopies.     

Detecting diminutive colorectal lesions at colonoscopy: a randomised controlled trial of pan-colonic versus targeted chromoscopy

BACKGROUND: Diminutive and flat colorectal lesions can be difficult to detect using conventional colonoscopic techniques. Previous data have suggested that pan-chromoscopy may improve detection rates. No randomised control trial has been performed examining detection rates of such lesions while controlling for extubation time and lavage effect. AIM: We conducted a randomised controlled trial of pan-colonic chromoscopic colonoscopy for the detection of diminutive and flat colorectal lesions while controlling for extubation time and lavage effect. METHODS: Consecutive patients attending for routine colonoscopy were randomised to either pan-chromoscopy using 0.5% indigo carmine (IC) or targeted chromoscopy (control group). A minimum diagnostic extubation time was set at eight minutes with controls undergoing a matched volume of saline wash. RESULTS: A total of 260 patients were randomised; 132 controls and 128 to pan-colonic chromoscopy. Extubation times did not differ significantly between the control (median 15 minutes (range 8-41)) and chromoscopy (median 17 minutes (range 8-39)) groups. The volume of IC used in the pan-chromoscopy group (median 68 ml (range 65-90)) and normal saline used in the control group (69 ml (range 60-93)) did not differ significantly. There was a statistically significant difference between the groups regarding the total number of adenomas detected (p<0.05) with significantly more diminutive (<4 mm) adenomas detected in the pan-chromoscopy group (p = 0.03). Pan-chromoscopy diagnosed more diminutive and flat lesions in the right colon compared with controls (p<0.05), with more patients with multiple adenomas (>3) detected using pan-chromoscopy (p<0.01). Hyperplastic lesions were more commonly detected in the pan-chromoscopy group compared with controls (p<0.001). More hyperplastic polyps were detected in the left colon (86% rectosigmoid) using chromoscopy compared with controls. CONCLUSION: Chromoscopy improves the total number of adenomas detected and enhances the detection of diminutive and flat lesions. Importantly, eight diminutive lesions had foci of high grade dysplasia. Chromoscopy may benefit patients, assuming a high risk of colorectal cancer, and help in risk stratification and planning follow up colonoscopy intervals.     

Meta-analysis for evaluating the accuracy of endoscopy with narrow band imaging in detecting colorectal adenomas

Background and Aim: The aim of this study was to determine whether the use of the narrow band imaging (NBI) system could enhance the accuracy of adenoma detection during an endoscopic examination of the colon and rectum. Methods: MEDLINE, EMBASE, and the Cochrane Library databases were searched along with a hand search of abstracts from relevant conferences up to June 2011. The rates of adenoma and flat adenoma detection, and withdrawal time were analyzed using Review Manager 4.2. Results: A total of 3049 subjects in eight trials were included. Meta‐analysis revealed that there was no statistically significant difference in the rates of adenoma detection between the NBI group and the white light colonoscopy group (pooled relative risk [RR]: 1.09, 95% confidence interval [CI]: 1.00–1.19, P = 0.05). However, after exclusion of high‐definition television modalities, the rate of adenoma detection by NBI was significantly higher than that by white light, particularly for patients with one adenoma (pooled RR 1.36, 95%CI 1.07–1.71, P = 0.02). Endoscopy with the NBI system significantly increased the rate of flat adenoma detection (pooled RR 1.96, 95%CI 1.09–3.52, P = 0.02). However, endoscopy with NBI had longer withdrawal time than that with white light (pooled weighted mean difference: 0.90, 95%CI: 0.38–1.42, P = 0.0006). Conclusions: Endoscopy with NBI seems to improve the detection of flat adenomas, particularly with high‐definition technology, but prolongs the withdrawal time. These results indicate that endoscopy routinely using the NBI system for the surveillance of adenomas may be recommended after the technique is further modified.     

The effect of small or diminutive adenomas at baseline colonoscopy on the risk of developing metachronous advanced colorectal neoplasia: KASID multicenter study

BackgroundThe clinical significance of diminutive or small adenomas remains ill defined.AimsWe evaluated the clinical impact of diminutive or small adenomas at baseline on the risk of developing metachronous advanced colorectal neoplasia (CRN).MethodsThis multicenter, retrospective cohort study included 2252 patients with 1 or more colorectal adenomas at baseline and subsequent follow-up colonoscopy. Baseline colonoscopy findings were classified into 5 groups: 1 or 2 tubular adenomas (TAs) (<10 mm); 3–10 diminutive TAs (≤5 mm); 3–10 TAs, including 1 or 2 small adenomas (6–10 mm); 3–10 TAs, including 3 or more small adenomas; and advanced adenoma.ResultsIn multivariate analysis, after adjusting for possible confounding variables (age at baseline, sex, body mass index, smoking habits, family history of colorectal cancer, regular use of aspirin or NSAIDs, and adenoma location), 3–10 TAs including 3 or more small adenomas (hazard ratio [HR] = 2.36, p = 0.034) and advanced adenoma (HR = 2.14, p < 0.001) were independent predictors for the risk of developing metachronous advanced CRN. However, 3–10 diminutive TAs or 3–10 TAs, including 1 or 2 small adenomas, were not associated with this outcome.ConclusionsMultiplicity of diminutive TAs, without advanced lesions, showed no clinical significance for risk of developing metachronous advanced CRN.     

High yields of small and flat adenomas with high-definition colonoscopes using either white light or narrow band imaging

BACKGROUND & AIMS: Detection of adenomas is an important goal of colonoscopy. Narrow band imaging (NBI) might highlight adenomas and lead to higher rates of adenoma detection. METHODS: This was a randomized controlled trial of colonoscopy withdrawal in white light versus NBI in 434 patients aged 50 years or older with intact colons. All examinations were performed by a single experienced endoscopist with a known high detection rate of adenomas using high-definition, wide-angle (170 degrees field of view) colonoscopes. RESULTS: There was no difference in the percent of patients with >or=1 adenoma for the entire cohort in white light (67%) versus NBI (65%) (P = .61) or in the subset of 257 patients with indication screening (58% vs 57%; P = .91). Both the prevalences of adenomas and the numbers of adenomas per colonoscopy are the highest ever reported in colonoscopy studies. The high prevalence rates of adenomas were accounted for by detection of large numbers of adenomas, including flat adenomas, which were 相似文献   

The role of high-magnification-chromoscopic colonoscopy in hereditary nonpolyposis colorectal cancer screening: a prospective "back-to-back" endoscopic study

BACKGROUND: In hereditary nonpolyposis colorectal cancer flat and diminutive adenomas occur, particularly in the right colon. Such lesions may assume a high risk of malignant transformation. Interval cancers are known to occur in this group. Chromoscopic colonoscopy enhances detection in patients assuming a moderate to high lifetime risk of colorectal cancer. AIM: To prospectively assess the efficacy of high-magnification-chromoscopic colonoscopy for the detection of neoplastic lesions in patients undergoing hereditary nonpolyposis colorectal cancer screening. METHODS: Twenty-five asymptomatic patients fulfilling modified Amsterdam criteria underwent "back-to-back" colonoscopy. Conventional colonoscopy with targeted chromoscopy was performed initially followed by pan-colonic chromoscopic colonoscopy. Diagnostic extubation times and volumes of normal saline and indigo carmine (IC) were controlled. RESULTS: Using conventional colonoscopy and targeted chromoscopy 24 lesions were detected in 13 patients (20 exophytic/4 flat). Pan-colonic chromoscopy identified a further 52 lesions in 16 patients (17 exophytic/35 flat). Pan-chromoscopy identified significantly more adenomas than conventional colonoscopy (p= 0.001) and a significantly high number of flat adenomas (p= 0.004). CONCLUSIONS: Pan-colonic chromoscopic colonoscopy improves detection of significant neoplastic lesions in hereditary nonpolyposis colorectal cancer screening. Pan-chromoscopy may help better stratify colorectal cancer "risk" in this cohort and aid planning of surveillance colonoscopic follow-up.     

Randomized,back-to-back trial of a new generation NBI with a high-definition white light (HQ290) for detecting colorectal polyps

Abstract

Background: The benefits of narrow band imaging (NBI) for improving the detection rate of colorectal polyps remain unclear. New generation NBI using the 290 system (290-NBI) provides an at least two-fold brighter image than that of the previous version. We aimed to compare polyp miss rates between 290-NBI colonoscopy and high-definition white light endoscopy (HDWL).

Methods: In total, 117 patients were randomized to undergo either 290-NBI or HDWL from June 2015 to February 2017. In the HDWL group, we performed HDWL as an initial inspection, followed by a second inspection with NBI. In the 290-NBI group, NBI was performed as the initial inspection, followed by a second inspection with HDWL. We compared polyp and adenoma detection rates and polyp miss rates (PMR) between the two groups and analyzed the factors associated with the PMR.

Results: In total, 127 polyps were detected in the 117 patients. No differences in adenoma or polyp detection rates were observed between the two groups. The PMR for 290-NBI was 20.6% and that for HDWL was 33.9% (p?=?.068). However, the non-adenomatous PMR for 290-NBI was significantly lower than that of HDWL (11.5% vs. 52.2%, p?=?.002). Furthermore, the miss rates of polyps on the left side of the colon, flat-type polyps, and non-adenomatous polyps were significantly lower in the 290-NBI than HDWL.

Conclusions: New generation NBI may reduce PMR, especially of flat-type and non-adenomatous polyps and those on the left side of the colon. (UMIN000025505)     

Total colonic dye-spray increases the detection of diminutive adenomas during routine colonoscopy: a randomized controlled trial

BACKGROUND: Small adenomas may be missed during colonoscopy, but chromoscopy has been reported to enhance detection. The aim of this randomized-controlled trial was to determine the effect of total colonic dye spray on adenoma detection during routine colonoscopy. METHODS: Consecutive outpatients undergoing routine colonoscopy were randomized to a dye-spray group (0.1% indigo carmine used to coat the entire colon during withdrawal from the cecum) or control group (no dye). RESULTS: Two hundred fifty-nine patients were randomized, 124 to the dye-spray and 135 to the control group; demographics, indication for colonoscopy, and quality of the preparation were similar between the groups. Extubation from the cecum took a median of 9:05 minutes (range: 2:48-24:44 min) in the dye-spray group versus 4:52 minutes (range: 1:42-15:21 min) in the control group (p < 0.0001). The proportion of patients with at least 1 adenoma and the total number of adenomas were not different between groups. However, in the dye-spray group significantly more diminutive adenomas (<5 mm) were detected proximal to the sigmoid colon (p = 0.026) and more patients were identified with 3 or more adenomas (p = 0.002). More non-neoplastic polyps were detected throughout the colon in the dye-spray group (p = 0.003). There were no complications. CONCLUSIONS: Dye-spray increases the detection of small adenomas in the proximal colon and patients with multiple adenomas, but long-term outcomes should be studied to determine the clinical value of these findings.     

Patient age and duration of colonoscopy are predictors for adenoma detection in both proximal and distal colon

AIM: To investigate the relation of patient characteristics and procedural parameters to the endoscopic detection rate of colonic adenomas. Further to study,which factors may be capable to predict the localization of adenomatous lesions.METHODS: We used the data base of a prospective randomized colonoscopy study(The Colo Cap trial) to identify patients being diagnosed with colon adenoma. Logistic regression analysis was conducted to reveal predictors for adenoma detection in the entire colon and also with respect to the proximal and distal part. Covariates including age, gender, duration of colonoscopy and comorbidities were defined to determine association between predictors and adenoma detection.RESULTS: Equal numbers of adenomas were detected in the proximal and distal side of the splenic flexure [126(57%) vs 94(43%), P = 0.104]. Simultaneous occurrence of adenomas in both sides of the colon was rare. The appearance of both proximal and distal adenoma was associated with increasing age(P = 0.008 and P = 0.024) and increasing duration of colonoscopy(P < 0.001 and P = 0.001). Male gender was a predictor for adenoma detection in the proximal colon(P = 0.008) but statistical significance was slightly missed with respect to the distal colon(P = 0.089). Alcohol abuse was found to be a predictor for the detection of distal adenoma(P = 0.041). CONCLUSION: Increasing age and longer duration of colonoscopy are factors with a strong impact on adenoma detection both in the proximal and distal colon. Since proximal adenomas occurred in absence of distal adenomas, complete colonoscopy should be performed for screening.     

Acceptability, effectiveness, and cost-effectiveness of internet-based exposure treatment for irritable bowel syndrome in a clinical sample: a randomized controlled trial

Background

A colonoscopy may frequently miss polyps and cancers. A number of techniques have emerged to improve visualization and to reduce the rate of adenoma miss.

Methods

We conducted a randomized controlled trial (RCT) in two clinics of the Gastrointestinal Department of the Sanitas University Foundation in Bogota, Colombia. Eligible adult patients presenting for screening or diagnostic elective colonoscopy were randomlsy allocated to undergo conventional colonoscopy or narrow-band imaging (NBI) during instrument withdrawal by three experienced endoscopists. For the systematic review, studies were identified from the Cochrane Library, PUBMED and LILACS and assessed using the Cochrane risk of bias tool.

Results

We enrolled a total of 482 patients (62.5% female), with a mean age of 58.33 years (SD 12.91); 241 into the intervention (NBI) colonoscopy and 241 into the conventional colonoscopy group. Most patients presented for diagnostic colonoscopy (75.3%). The overall rate of polyp detection was significantly higher in the conventional group compared to the NBI group (RR 0.75, 95%CI 0.60 to 0.96). However, no significant differences were found in the mean number of polyps (MD -0.1; 95%CI -0.25 to 0.05), and the mean number of adenomas (MD 0.04 95%CI -0.09 to 0.17). Meta-analysis of studies (regardless of indication) did not find any significant differences in the mean number of polyps (5 RCT, 2479 participants; WMD -0.07 95% CI -0.21 to 0.07; I2 68%), the mean number of adenomas (8 RCT, 3517 participants; WMD -0.08 95% CI -0.17; 0.01 to I2 62%) and the rate of patients with at least one adenoma (8 RCT, 3512 participants, RR 0.96 95% CI 0.88 to 1,04;I2 0%).

Conclusion

NBI does not improve detection of colorectal polyps when compared to conventional colonoscopy (Australian New Zealand Clinical Trials Registry ACTRN12610000456055).     

Narrow band imaging vs. high definition colonoscopy for detection of colorectal adenomas in patients with positive faecal occult blood test: A randomised trial

BackgroundThe impact of narrow band imaging in improving the adenoma detection rate in a screening scenario is still unclear.AimTo evaluate whether narrow band imaging compared with high definition white light colonoscopy can enhance the adenoma detection rate during screening colonoscopy.MethodsConsecutive patients presenting for screening colonoscopy were included into this study and were randomly assigned to the narrow band imaging group (Group 1) or standard colonoscopy group (Group 2). Primary end point was the adenoma detection rate and secondary aim was the detection rate of advanced adenomas.ResultsOverall, 117 patients were allocated to Group 1 and 120 to Group 2. Both the adenoma detection rate and the detection rate of advanced adenomas were not significantly different between the two groups (respectively, 52.1% vs. 55%, RR = 0.95, 95% CI 0.75–1.20; 32.5% vs. 44.2%, RR = 0.74, 95% CI 0.53–1.02). No significant difference between the proportions of polypoid and flat adenomas was found. Male gender, no prior history of screening, and endoscopist's adenoma detection rate were independent predictive factors of higher advanced adenoma detection rate.ConclusionsIn a screening scenario, narrow band imaging did not improve the adenoma nor advanced adenoma detection rates compared to high definition white light colonoscopy.     

Detection rate and proximal shift tendency of adenomas and serrated polyps: a retrospective study of 62,560 colonoscopies

Purpose

The purpose of this study is to estimate the detection rates of adenomas and serrated polyps and to identify proximalization and associate risk factors in patients from Southern China.

Methods

Consecutive patients undergoing colonoscopy from 2004 to 2013 in Guangzhou were included. The proportions of proximal adenomas to advanced adenomas and serrated polyps were compared and potential predictors were evaluated.

Results

Colonoscopies (n?=?62,560) were performed, and 11,427 patients were diagnosed with polyps. Detection rates for adenomas, hyperplastic polyps, and serrated adenomas were 12.0, 2.5, and 0.2 patients per 100 colonoscopies. When comparing the 1st (2004–2008) to the 2nd period (2009–2013), adenoma and serrated polyp detection in proximal and distal colon both increased significantly (proximal colon [adenoma 3.9 vs. 6.1 patients/100 colonoscopies, P?<?0.001; serrated polyp 0.4 vs. 1.1 patients/100 colonoscopies, P?<?0.001]; distal colon [adenoma 6.6 vs. 7.2 patients/100 colonoscopies, P?=?0.003; serrated polyp 1.2 vs. 2.4 patients/100 colonoscopies, P?<?0.001]). Advanced adenoma detection increased over these two periods only in proximal colon (1st vs. 2nd period: 1.5 vs. 2.4 patients/100 colonoscopies, P?<?0.001), not the distal colon (P?=?0.114). Multivariate analyses showed that diagnostic period was an independent predictor for adenoma proximalization (OR?=?1.36, 95% CI 1.25–1.48, P?<?0.001), but not for advanced adenomas (P?=?0.117) or serrated polyps (P?=?0.928).

Conclusions

Adenomas and serrated polyps were increasingly detected throughout the colon, whereas advanced adenomas were only in proximal colon. A proximal shift tendency detected by colonoscopy was observed for adenomas, but not advanced adenomas or serrated polyps, in Southern China. The screening for proximal polyps should be emphasized and colonoscopy might be a preferred initial screening tool.

     

The mean number of adenomas per procedure should become the gold standard to measure the neoplasia yield of colonoscopy: A population-based cohort study

BackgroundMeasuring adenoma detection is a priority in the quality improvement process for colonoscopy. Our aim was (1) to determine the most appropriate quality indicators to assess the neoplasia yield of colonoscopy and (2) to establish benchmark rates for the French colorectal cancer screening programme.MethodsRetrospective study of all colonoscopies performed in average-risk asymptomatic people aged 50–74 years after a positive guaiac faecal occult blood test in eight administrative areas of the French population-based programme.ResultsWe analysed 42,817 colonoscopies performed by 316 gastroenterologists. Endoscopists who had an adenoma detection rate around the benchmark of 35% had a mean number of adenomas per colonoscopy varying between 0.36 and 0.98. 13.9% of endoscopists had a mean number of adenomas above the benchmark of 0.6 and an adenoma detection rate below the benchmark of 35%, or inversely. Correlation was excellent between mean numbers of adenomas and polyps per colonoscopy (Pearson coefficient r = 0.90, p < 0.0001), better than correlation between mean number of adenomas and adenoma detection rate (r = 0.84, p = 0.01).ConclusionThe mean number of adenomas per procedure should become the gold standard to measure the neoplasia yield of colonoscopy. Benchmark could be established at 0.6 in the French programme.     

Clinical impact of colonoscopy for patients with early gastric cancer treated by endoscopic submucosal dissection: A matched case–control study

BackgroundGastric cancer frequently occurs synchronously with colorectal cancer (CRC).AimsThe aim of the present study was to assess the value of colonoscopy in patients with primariy early gastric cancer (EGC) indicated for endoscopic submucosal dissection (ESD) and to identify predictors for the risk of high-risk adenomas.MethodsA total of 130 patients with EGC, who underwent both colonoscopy and gastric ESD, and 260 controls matched for age and sex, who underwent a colonoscopy as part of our institutional health check-up program.The prevalence of high-risk adenomas in EGC patients vs. controls was evaluated.ResultsHigh-risk adenomas were found in 43 (33%) EGC patients and 37 (14%) controls (P < 0.01). Multivariate analysis showed the presence of EGC was significantly associated with high-risk adenoma [odds ratio (OR) 2.8, 95% confidence interval (CI): 1.7–4.9]. Among EGC patients, high serum CEA level (OR 2.4, 95% CI: 1.2–5.0) was an independent predictor for high-risk adenoma.ConclusionsPatients with EGC had a significant risk for colorectal cancer. When endoscopists detected an early gastric cancer indicated for ESD, colonoscopy should be considered for EGC patients with high serum CEA levels.     

Risk factors associated with the detection and missed diagnosis of colorectal flat adenoma: a Chinese multicenter observational study

Abstract

Objectives: Flat colorectal adenomas have a high risk of malignancy; however, their detection is often difficult due to their flat morphology. In this retrospective, large-scale study, we investigated the prevalence and characteristics of flat adenomas in a population in China.

Methods: We analyzed the data collected for 16951 consecutive patients who underwent colonoscopy at four participating hospitals between September 2013 and September 2015. All colonoscopies were performed without magnification.

Results: Among the 1,6951 patients, 2938 (17.3%) had adenoma and 796 (4.7%) had flat adenomas. The detection of flat adenoma showed a weak correlation with the detection of adenoma (r?=?0.666). Multivariable logistic regression analysis revealed the following independent factors influencing the detection of flat adenomas: patient-related factors of age, presence of warning symptoms, history of adenomas and bowel preparation as well as endoscopist-related factors of endoscopist’s level of proficiency, number of colonoscopy operators and withdrawal time.

Conclusions: The prevalence of flat adenomas in our study on Chinese patients was consistent with that reported from other countries. Factors conducive to the detection of flat adenomas were patient age of >?60 years, warning symptoms, history of adenoma, good bowel preparation, experienced endoscopist, single-operator colonoscopy and colonoscopy withdrawal time of >6?min.     

Variation in Colonoscopic Technique and Adenoma Detection Rates at an Academic Gastroenterology Unit

The purpose of this research is to evaluate the quality of colonoscopy at an academic institution with a focus on factors influencing withdrawal times and adenoma detection rates. Procedural data and pathologic results of 550 consecutive screening colonoscopies in average risks patients (mean [±SD] age, 57 ± 7.6, 44% male) completed by ten academic gastroenterologists were reviewed. Per individual gastroenterologist, the adenoma detection rates ranged widely from 0.09 to 0.82 adenomas per patient with a mean of 0.46 for the group. The mean withdrawal time was 7.0 min for the group and ranged from 3.4 to 9.6 min. There was a significant positive relationship between the number of adenomas detected and the withdrawal time (P = 0.006). Endoscopists with cecal intubation time to withdrawal time ratios of less than 1 detected significantly more adenomas compared to endoscopists with ratios greater than 1 (P = 0.001). (1) Significant variation in academic gastroenterologists’ abilities to detect adenomas during screening colonoscopies exists. (2) Colonoscopic withdrawal time and the cecal intubation to withdrawal time ratio are important factors associated with increased adenoma detection rates.     

Detection of Colorectal Neoplasms Using Linked Color Imaging: A Prospective,Randomized, Tandem Colonoscopy Trial

Background and aimsA higher adenoma detection rate (ADR) has been shown to be related to a lower incidence and mortality of colorectal cancer. We analyzed the efficacy of linked color imaging (LCI) by assessing the detection, miss, and visibility of various featured adenomas as compared with white light imaging (WLI).MethodsThis was a prospective, randomized, tandem trial. The participants were randomly assigned to 2 groups: first observation by LCI, then second observation by WLI (LCI group); or both observations by WLI (WLI group). Suspected neoplastic lesions were resected after magnifying image-enhanced endoscopy. The primary outcome was to compare the ADR during the first observation. Secondary outcomes included evaluation of adenoma miss rate (AMR) and visibility score.ResultsA total of 780 patients were randomized, 700 of whom were included in the final analysis. The ADR was 69.6% and 63.2% in the LCI and WLI groups, respectively, with no significant difference. However, LCI improved the average ADR in low-detectors compared with high-detectors (76.0% vs 55.1%; P < .001). Total AMR was 20.6% in the LCI group, which was significantly lower than that in the WLI group (31.1%) (P < .001). AMR in the LCI group was significantly lower, especially for diminutive adenomas (23.4% vs 35.1%; P < .001) and nonpolypoid lesions (25.6% vs 37.9%; P < .001) compared with the WLI group.ConclusionAlthough both methods provided a similar ADR, LCI had a lower AMR than WLI. LCI could benefit endoscopists with lower ADR, an observation that warrants additional study. (UMIN Clinical Trials Registry, Number: UMIN000026359).     

Surveillance after positive colonoscopy based on adenoma characteristics

BackgroundPatients with adenomatous polyps are at increased risk for developing colorectal cancer based on the characteristics and number of polyps, but less is known about the individual and combined contribution of these factors. This study aimed to better characterize the risk of advanced adenoma and cancer in patients with positive baseline colonoscopy.MethodsPatients who had polyps at baseline colonoscopy were included in this retrospective cohort study (N = 1165) and were categorized into 6 groups: (1) 1–2 non-advanced adenomas (NAA’s), (2) ≥3 NAA’s, (3) advanced tubular adenoma, (4) small tubulovillous adenoma (TVA), (5) large TVA and (6) multiple advanced adenomas (MAA’s). Findings at surveillance colonoscopy were documented in each group.ResultsThe combined incidence of advanced adenoma, ≥3 NAA’s, and colorectal cancer at surveillance colonoscopy was significantly higher in the baseline large TVA (29.2%) than small TVA groups (13.5%, P < 0.001), as well as in the MAA’s group (44.1%) compared with large TVA group (P = 0.02). The incidence of colorectal cancer, however, was not significantly different between the groups.ConclusionsThe size of the polyp and the number of advanced lesions are more important than its histology for predicting the risk of high-risk metachronous lesions at follow-up.     

Impacto del proceso de enseñanza endoscópica en la detección de adenomas colónicos

BackgroundThere has been little reported experience in the Latin American hospital setting in relation to the impact of the endoscopic training process on colonoscopy quality.AimsTo determine the effect that training in the technique of colonoscopy has on adenoma detection in an Argentinian teaching hospital.Material and methodWithin the time frame of July 2012 and July 2013, 3 physicians received training in colonoscopy from 4 experienced endoscopists. The colonoscopies performed by the supervised trainees were compared with those carried out by the experienced endoscopists.ResultsA total of 318 colonoscopies performed by any one of the 3 supervised trainees and 367 carried out by any one of the experienced endoscopists were included. The univariate analysis showed a non-significant difference in the detection rate of adenomas (30.4 vs. 24.7%, P = .09). In the multivariate analysis, the detection rate of adenomas was significantly higher in the colonoscopies performed by one of the 3 trainees (odds ratio = 1.72 [1.19-2.48]).ConclusionsThe supervised involvement of endoscopic trainees has a positive effect on adenoma detection.     

Benefits and Limitations of Cap-Fitted Colonoscopy in Screening Colonoscopy

Background

Colonoscopy is widely used to detect colorectal cancer and to remove precancerous lesions to reduce the risk of colonic cancer.

Aims

To examine the benefits and limitations of cap-fitted colonoscopy compared to conventional colonoscopy in terms of technical performance and colorectal adenoma detection rate.

Methods

Screening colonoscopies performed from 2009 to 2010 with or without a transparent cap were retrospectively examined to compare the rate of successful intubation, cecal intubation time, and number, size, shape, and location of adenomas detected. An inclusion criterion was visualization of >95 % of the right colon.

Results

Data from 2,301 colonoscopies (1,165 with cap-fitted colonoscopy, 1,136 without the transparent cap) were retrospectively analyzed. Procedures were performed by four experienced endoscopists. The subjects’ demographic characteristics and technical performances were similar between the two methods. The only significant difference in the technical performance between the two techniques was a shorter cecal intubation time with cap-fitted colonoscopy (5.3 vs. 6.6 min; p = 0.045) by one endoscopist. The total number of adenomas detected was significantly higher with cap-fitted colonoscopy than without the cap (586 vs. 484, respectively; p < 0.0001). Adenoma detection with cap-fitted endoscopy was significantly higher in the right colon than in the left colon (19 vs. 12 %, respectively; p = 0.0001).

Conclusion

Cap-fitted colonoscopy did not improve the technical aspects of colonoscopy but significantly increased adenoma detection, especially in the right colon. It did not increase the detection rate of flat or depressed adenomas.