Interval colorectal cancer after colonoscopy. Clin Colorectal Cancer. 2015;14:46-51. [PMID: 25510180 DOI: 10.1016/j.clcc.2014.11.001]

A Novel Convolutional Neural Network Model as an Alternative Approach to Bowel Preparation Evaluation Before Colonoscopy in the COVID-19 Era: A Multicenter, Single-Blinded, Randomized Study

INTRODUCTION

Adequate bowel preparation is key to a successful colonoscopy, which is necessary for detecting adenomas and preventing colorectal cancer. We developed an artificial intelligence (AI) platform using a convolutional neural network (CNN) model (AI-CNN model) to evaluate the quality of bowel preparation before colonoscopy.

METHODS

This was a colonoscopist-blinded, randomized study. Enrolled patients were randomized into an experimental group, in which our AI-CNN model was used to evaluate the quality of bowel preparation (AI-CNN group), or a control group, which performed self-evaluation per routine practice (control group). The primary outcome was the consistency (homogeneity) between the results of the 2 methods. The secondary outcomes included the quality of bowel preparation according to the Boston Bowel Preparation Scale (BBPS), polyp detection rate, and adenoma detection rate.

RESULTS

A total of 1,434 patients were enrolled (AI-CNN, n = 730; control, n = 704). No significant difference was observed between the evaluation results ("pass" or "not pass") of the groups in the adequacy of bowel preparation as represented by BBPS scores. The mean BBPS scores, polyp detection rate, and adenoma detection rate were similar between the groups. These results indicated that the AI-CNN model and routine practice were generally consistent in the evaluation of bowel preparation quality. However, the mean BBPS score of patients with "pass" results were significantly higher in the AI-CNN group than in the control group, indicating that the AI-CNN model may further improve the quality of bowel preparation in patients exhibiting adequate bowel preparation.

DISCUSSION

The novel AI-CNN model, which demonstrated comparable outcomes to the routine practice, may serve as an alternative approach for evaluating bowel preparation quality before colonoscopy.

Hsa_circ_0005100 regulates tumorigenicity of colorectal carcinoma via miR-145-5p/MACC1 axis

BACKGROUND

Circular RNAs (circRNAs) are a kind of RNA molecules involved in the regulation of cancer progression, including colorectal carcinoma (CRC); nevertheless, their regulation mode is blurry. In the present work, we attempted to reveal the characteristics of hsa_hsa_circ_0005100 in CRC.

METHODS

Differential expressions of hsa_circ_0005100, FMN2 mRNA, microRNA-145-5p (miR-145-5p), and MACC1 were indicated by qRT-PCR and Western blot. The capacities of cell growth and motility were validated by the MTT assay, flow cytometry assay, EdU assay, colony formation assay, and transwell assay. Moreover, the targeted relationship of miR-145-5p and hsa_circ_0005100 or MACC1 was distinguished by dual-luciferase reporter assay. The animal experiment was implemented to confirm the influence of hsa_circ_0005100 on tumorigenesis in vivo.

RESULTS

Hsa_circ_0005100 and MACC1 expression levels were increased, but miR-145-5p expression level was diminished in CRC. Hsa_circ_0005100 knockdown repressed cell proliferation, cell cycle, migration, and invasion, while expedited cell apoptosis in CRC cells. Furthermore, miR-145-5p was disclosed to block CRC via overturning MACC1. Hsa_circ_0005100 targeted miR-145-5p to modulate MACC1. Additionally, hsa_circ_0005100 knockdown also attenuated tumorigenesis in vivo.

CONCLUSION

Hsa_circ_0005100 was a vital regulator in the development of CRC by miR-145-5p/MACC1 axis, which deepened the understanding of CRC pathogenesis from circRNA insights.

Clinical and endoscopic characteristics of post-colonoscopy colorectal cancers detected within 10 years after a previous negative examination

Background and study aims We sometimes encounter colorectal cancer (CRC) that is discovered during the time interval between initial colonoscopy and the recommended follow-up examination. Although several studies reported such cases of CRC, most were based on registry data, which implied that the endoscopic quality was not consistent or guaranteed. We aimed to clarify these clinical and endoscopic characteristics at our high-volume center where a retrospective survey could be precisely performed.

Patients and methods We retrospectively analyzed patients with CRC who underwent endoscopic resection or surgery from April 2002 to December 2010, categorizing them into two groups: a “study group” of patients with a negative colonoscopy during the previous 10 years, and a “control group” of patients without a previous colonoscopy or with a previous colonoscopy more than 10 years prior.

Results A total of 2042 patients had CRC, among which 55 patients were classified into the study group and the remaining 1989 into the control group. The CRC cases in the study group showed a significant association with smaller (< 30 mm) tumor size (odds ratio [OR] 2.3; 95 % confidence interval [CI] 1.3–4.0) and proximal tumor site (OR 1.7; 95 %CI 0.9–2.9). In addition, right-sided and depressed-type T1 CRCs were significantly more common in the study group.

Conclusions Tumor size and location were associated with CRCs detected within 10 years after the negative examination. In addition, depressed-type T1 CRCs were more common. Therefore, we should pay more attention to small, right-sided, or depressed-type tumors in daily colonoscopy.

Prevalence and characteristics of post-colonoscopy colorectal cancers in a New Zealand regional centre: a 10-year analysis

BACKGROUND

Post-colonoscopy colorectal cancers (PCCRC) are cancers that appear following a colonoscopy in which no cancer is diagnosed. The occurrence of PCCRC is thought to be multifactorial, reflecting both endoscopy quality and potential differences in tumour biology between detected colorectal cancers and PCCRC.

AIM

To identify the prevalence and characteristics of PCCRC in a New Zealand regional centre over a 10-year period.

METHOD

All cases of colorectal cancer (n = 1055) in the Bay of Plenty region between 1 February 2009 and 1 February 2019 were cross-referenced with endoscopy coding records to identify patients who had undergone colonoscopy within the preceding 6-60 months in which cancer was not identified.

RESULTS

A total of 46 patients were identified to have PCCRC, giving a prevalence of 4.4%. The majority of these patients were older (80% aged 65 years or over) and female (67%). The mean interval between index colonoscopy and diagnosis of PCCRC was 3.03 years. Most (80%) patients had existent pathology (diverticular disease or colonic polyps) at index colonoscopy, and a significant proportion (43%) developed cancer in the same colonic segment. PCCRC were evenly distributed between the left (50%) and right (50%) colon. The majority of patients (63%) had early-stage cancer.

CONCLUSIONS

The prevalence of PCCRC in a New Zealand cohort is consistent with other international reports. Most patients with PCCRC are older, female and have early-stage disease. Of interest, a high proportion of patients developed cancer within a colonic segment with existent pathology, suggesting either missed lesions or incomplete polyp resection.

Quality Improvement of Bowel Preparation for Screening Colonoscopies: A Study of Hospital Team Resource Management in Taiwan

BACKGROUND AND OBJECTIVES

This study aimed to investigate the impact of patient education using a medical team resource management (TRM) method on the adequacy of bowel preparation.

METHODS

The study setting was a single hospital in northern Taiwan, and a total of 2104 (884 female, 1220 male) healthy subjects who underwent a health checkup colonoscopy screening were enrolled before and after the application of the TRM program intervention. The efficacy of the TRM intervention and the factors affecting bowel preparation were estimated using multivariate logistic regression.

RESULTS

The prevalence of adequate bowel preparation improved significantly from the preintervention period to the postintervention and validation periods, which had prevalence of 79.0%, 81.3%, and 84.0%, respectively. Using the preintervention period prevalence as a reference, the adjusted odds ratios (aORs) for adequate bowel preparation in the postintervention and validation periods were 2.199 (95% confidence interval [CI]: 1.538-3.142) and 2.035 (1.525-2.716), respectively. Men had a lower probability of adequate cleansing than women (aOR = 0.757; 95% CI = 0.598-0.957), and purgative containing polyethylene glycol had a lower probability of adequate cleansing than purgative containing sodium phosphate (aOR = 0.366; 95% CI: 0.277-0.483).

CONCLUSIONS

Bowel preparation quality for colonoscopy could be improved by enhancing patient education via TRM, and we suggest that effective quality improvement schemes should be proposed for health-screening programs.

Cost-effectiveness and budget impact analyses of colorectal cancer screenings in a low- and middle-income country: example from Thailand

Objectives: Colorectal cancer (CRC) screening programs have been reported to be cost-effective in many high-income countries. However, there was no such study in low- and middle-income countries. This study aimed to evaluate cost-effectiveness and budget impact of CRC screening modalities for average-risk persons in Thailand.Methods: A decision tree coupled with a Markov model was used to estimate lifetime costs and health benefits of fecal immunochemical test (FIT) and colonoscopy using a societal perspective. The input parameters were obtained from a CRC screening project at a Thai tertiary care hospital, Thai health care costs and databases, and systematic literature review. Results were reported as incremental cost-effectiveness ratios (ICERs) in 2017 US Dollars (USD) per quality-adjusted life year (QALY) gained. Sensitivity analyses were performed to assess the influence of parameter uncertainty. Finally, budget impact analysis was conducted.Results: At the Thai ceiling threshold of societal willingness-to-pay of 4,706 USD, the screening colonoscopy every 10 years and annual FIT, starting at age 50, was cost-effective, as compared to no screening resulting in 15.09 and 15.00 QALYs with the ICERs of 600.20 and 509.84 USD/QALY gained, respectively. Colonoscopy every 10 years and annual FIT could prevent 17.9% and 5.7% of early stage cancer and 27.8% and 9.2% of late stage cancer per 100,000 screening over lifetime when compared to no screening, respectively. The colonoscopy screening was cost-effective with the ICER of 646.53 USD/QALY gained when compared to FIT. The probabilities of being cost-effective for the colonoscopy and FIT were 75% and 25%, respectively. Budget impact analysis showed the colonoscopy screening required an 8-times higher budget than FIT.Conclusions: Colonoscopy offers the best value for money of CRC screenings in Thailand. Annual FIT is potentially feasible since it requires less resources. Our findings can be used as part of evidence for informing policy decision making.Key points for decision makersThere was a lack of cost-effective study of colorectal cancer screening programs in low- and middle-income countries.This study evaluated lifetime health outcomes and costs, and the cost-effectiveness of colorectal screening options for average-risk persons in Thailand.Colonoscopy screening every 10 years is cost-effective with high probability of being cost-effective as compared with annual fecal immunochemical test.Screening by annual fecal immunochemical test is more feasible in terms of human resource and budgetary burden.Colorectal screening programs provides an opportunity for early diagnosis and treatments to prevent advance colorectal stages and avoid higher consequent costs.This study contributes a new evidence-based knowledge for Thailand and can be used to support policy decision making process.

Temporal Trends and Risk Factors for Postcolonoscopy Colorectal Cancer

BACKGROUND

Colonoscopy is effective for colorectal cancer (CRC) prevention, yet patients may develop CRC despite adhering to screening/surveillance intervals. There are limited data on predictive factors associated with these postcolonoscopy CRCs (PCCRCs). We aimed to measure PCCRC rates and identify risk factors for PCCRC.

METHODS

We performed a case-control study, comparing patients with PCCRCs to spontaneous CRCs diagnosed during a 12.5-year period at an academic medical center. PCCRCs were defined as CRCs diagnosed in between guideline-recommended screening/surveillance intervals.

RESULTS

During the 12.5-year period, of 1266 CRCs diagnosed, 122 (10%) were PCCRCs. 70% of PCCRCs were diagnosed within 5 years of a prior colonoscopy. There was an increasing trend for PCCRC rates in recent years [odds ratio (OR), 2.78; 95% confidence interval (CI), 1.51-5.09], with PCCRCs comprising 13.6% of cancers diagnosed in 2016 as compared with 5.7% of cancers diagnosed in 2005. Older age (OR per year, 1.02; 95% CI, 1.01-1.04), proximal colonic location (OR, 1.99; 95% CI, 1.20-3.33) and early stage (OR, 2.57; 95% CI, 1.34-4.95) were associated with PCCRCs. In total, 41% of PCCRCs were diagnosed by a different physician from the physician who did the prior colonoscopy, and 42% of physicians did not diagnose any of their PCCRC cases.

CONCLUSIONS

PCCRC rates are rising in recent years, likely reflecting the widespread adoption of colonoscopy as a primary screening tool, and are more common in older patients and those with proximal, early-stage tumors. The finding that a large proportion of PCCRCs are diagnosed by a different physician raises the concern that physicians are unaware of their own patients' PCCRCs.

Characteristics and consequences of missed gastric cancer: A multicentric cohort study

BACKGROUND

Missed gastric cancer (MGC) is poorly documented in Mediterranean populations.

AIMS

(1) To assess the rate, predictors and survival of MGC. (2) To compare MGC and non-MGC tumors.

METHODS

This is a retrospective-cohort study conducted at four centers. MGC was defined as cancer detected within three years after negative esophagogastroduodenoscopy. Gastric adenocarcinomas diagnosed between 2008-2015 were included. Patients with no follow-up were excluded.

RESULTS

During the study period 123,395 esophagogastroduodenoscopies were performed, with 1374 gastric cancers being diagnosed (1.1%). A total of 1289 gastric cancers were finally included. The overall rate of MGC was 4.7% (61/1289, 3.7-6%). A negative esophagogastroduodenoscopy in MGC patients was independently associated with PPI therapy (p < 0.001), previous Billroth II anastomosis (p = 0.002), and lack of alarm symptoms (p < 0.001). The most frequent location for MGC was the gastric body(52.4%). MGCs were smaller than non-MGCs (31 vs 41 mm, p = 0.047), more often flat or depressed (p = 0.003) and less likely to be encountered as advanced disease. Overall 2-year survival was similar between MGC (34.1%) and Non-MGC (35.3 %) (p = 0.59).

CONCLUSION

MGC accounted for nearly five percent of newly-diagnosed gastric adenocarcinomas. Overall survival was poor and not different between MGC and non-MGC.

Clinicopathologic and genetic characteristics of interval colorectal carcinomas favor origin from missed or incompletely excised precursors

Interval colorectal cancers may arise from missed or incompletely excised precursors or from a unique rapid progression pathway. We compared the clinicopathologic and molecular profiles of interval and matched non-interval colorectal cancer to determine whether interval colorectal cancers harbor any unique genetic characteristics. Fifty one of 982 colorectal cancer (5.2%) were categorized as interval colorectal cancer, defined as colorectal cancer detected in a diagnostic examination prior to the next recommended colonoscopy and at least 1 year after the last colonoscopy. Clinicopathologic characteristics of interval colorectal cancer were compared to non-interval colorectal cancer matched 1:1 on age, gender, and tumor location. Molecular profile of a subset of interval colorectal cancer (n = 20) and matched (1:2) non-interval colorectal cancer (n = 40) were evaluated using next generation sequencing. Interval colorectal cancer were more likely to occur in the right colon (55% vs. 35%; p = 0.02) and in patients > 70 years of age (55% vs. 34%; p = 0.002). Clinicopathologic features and aberrant DNA mismatch repair protein expression were not significantly different between interval and matched non-interval colorectal cancer. The frequency and spectrum of genetic alterations was also similar in interval and matched non-interval colorectal cancer. Similar findings were seen when analysis was restricted to interval colorectal cancer diagnosed <5 years after last colonoscopy (n = 42). Interval and non-interval colorectal cancers share similar clinicopathologic and genetic profiles when matched for tumor location. Interval colorectal cancers and are more likely to develop from missed or incompletely excised precursors rather than a unique rapid progression pathway.

Effectiveness of Intensive Endoscopic Screening for Esophageal Cancer in China: A Community-Based Study

Evidence is required to evaluate the effectiveness of population-level endoscopic screening for esophageal cancer (EC). In this study, 5,632 permanent residents aged 25-65 years from 6 villages in Hua County, Henan Province, China, were defined as the screening cohort and were offered intensive endoscopic screening. Residents of all 914 remaining villages in Hua County were included as the control cohort, and age-sex standardization was used to calculate the expected numbers of EC and upper gastrointestinal (GI) tract cancer cases and deaths in the screening cohort. The effectiveness of screening was assessed by comparing observed numbers of cases and deaths with expected numbers after 9-year follow-up of these screened subjects (2007-2016). In the screening cohort, 23 upper GI cancers (including 16 ECs) and 10 upper GI cancer deaths (including 5 EC deaths) were identified, and 47% (standardized incidence ratio = 0.53, 95% confidence interval (CI): 0.33, 0.87) and 66% (standardized mortality ratio = 0.34, 95% CI: 0.14, 0.81) reductions in cumulative EC incidence and mortality were found. For upper GI cancers, incidence and mortality were lowered by 43% (standardized incidence ratio = 0.57, 95% CI: 0.38, 0.86) and 53% (standardized mortality ratio = 0.47, 95% CI: 0.25, 0.88), respectively. This study showed that upper GI tract endoscopy is an effective population-level screening test for EC in high-risk regions.

The contribution of endoscopy quality measures to the development of interval colorectal cancers in the screening population: a systematic review

BACKGROUND

Colon cancer is the second most common cause of cancer-related death and an important cause of morbidity. The natural history of carcinogenesis, via the adenoma-carcinoma sequence, permits screening, which reduces the relative risk of mortality by up to 16%. The efficacy of a screening programme is limited by the growth of interval colorectal cancers between screening examinations. Quantifying the rate of interval cancers and delineating contributing endoscopic factors are crucial to maximise the benefit of a screening program.

METHODS

A systematic review was performed in accordance with PRISMA principles. Electronic databases were interrogated with a considered search strategy, and reference lists of retrieved papers were surveyed. For inclusion, studies included the rate of interval cancer (stated or calculated) and reported at least one of a predefined list of endoscopy characteristics. The primary outcome was to establish the rate of interval cancers. The secondary outcome was to determine the association between endoscopy quality measures and interval cancers.

RESULTS

The search yielded 2067 papers. Seventy-six full text papers were reviewed. Fifteen papers met the inclusion criteria. In total, there were 117,793 colon cancers, 7281 of which were interval lesions, giving an overall rate of 6.2%. The adenoma detection rate (ADR) of the endoscopist performing the index operation was the most consistent endoscopy factor associated with development of interval cancers. The impact of setting, volume and bowel preparation varied between papers.

CONCLUSION

Interval cancers reduce the efficacy of colorectal screening programmes. Ensuring the quality of the endoscopy process, specifically by increasing the ADR of practitioners, is crucial to the reduction of the rate of interval cancers.

Interval colorectal cancer after colonoscopy

INTRODUCTION AND AIMS

Interval colorectal cancer (iCRC) can occur due to missed lesions or to a newly developed lesion. The present study aimed to assess the iCRC rate and its characteristics in our population and find possible explanations.

MATERIALS AND METHODS

A retrospective study was conducted on patients with colorectal cancer (CRC) diagnosed between January 2011 and January 2015 at our department. Demographics, endoscopic data, and tumor characteristics (location, histology, staging) were collected. We identified patients diagnosed with CCR who underwent colonoscopy at our department in the previous 10years and presented the disease (iCRC) before the date of their next recommended exam. The cases of iCRC were characterized and compared with other CRC cases. Possible explanations for the appearance of iCRC were analyzed.

RESULTS

A total of 266 patients presented with CRC, 61.7% were men, and mean patient age was 70.7years. We identified 10 patients with iCRC: 6 were men, and mean patient age was 71.1years. Mean time for iCRC diagnosis after index colonoscopy was 3.5±1.84years. Tumor was located in the right colon in 50% of the patients with iCRC and in 24.5% of the patients without iCRC (P=.091). More patients with iCRC had a family history of CRC (50%) than the patients with reference CRC (3.1%) (P=.000).

CONCLUSIONS

In our case series, 3.76% of all CRC were iCRC. There were no statistically significant differences between patients with or without iCRC, with the exception of family history of CRC.

Colonoscopic withdrawal time and adenoma detection in the right colon

Shorter colonoscopic withdrawal time (CWT) has been associated with lower adenoma detection rate (ADR), which can increase the risk of interval colorectal cancer (ICC) that commonly arises in the right colon (RC). Therefore, a better ADR in the RC could decrease the incidence of ICC. We analyzed the relationship between CWT and ADR in the RC and entire colon.We retrospectively reviewed the patients who had undergone screening colonoscopy at Chungnam National University Hospital between March 2015 and February 2016. We enrolled 5370 patients in whom colonoscopies were performed by 7 gastroenterologists. We categorized patients into 4 groups in the RC and 6 groups in the entire colon by CWT. Multivariable analysis was used for detection of adenoma in the RC and entire colon.In the RC, the odds ratio (OR) of CWT longer than 3 minutes was 3.70, compared to CWT of <2 minutes [3.06-4.85, 95% confidence interval (CI), P < .001]. In the entire colon, the OR of CWT between 9 to 10 minutes and longer than 10 minutes was 3.34 [2.61-4.27, 95% CI, P < .001] and 3.49 [2.80-4.33, 95% CI, P < .001] compared to CWT of <6 minutes.Based on our result, we suggest that the optimum CWT in the RC should exceed 3 minutes, and considering the "ceiling effect," the optimum CWT in the entire colon should exceed 9 minutes.

Interval colorectal cancer: a challenging field in colorectal cancer

Accumulated evidence has shown that colonoscopy may not be a perfect tool in screening and reducing the incidence of the colorectal cancer (CRC), because interval CRC (I-CRC), a specific subgroup of CRCs, has been challenging the traditional detection technology in recent years. I-CRC is accounting for an increasing proportion in CRCs. However, the effective procedures to prevent and supervise I-CRC need to be explored. In this review, we summarized the incidence, causes, risk factors, characteristics and management of I-CRC. It would promote the awareness of the special value in the education and training for the gastroenterologists, which plays an important role in conquering CRC.

Right Versus Left Colon Cancer: Resectable and Metastatic Disease

OPINION STATEMENT

Colorectal cancer does not represent a single anatomic entity and side of origin has a key impact on prognosis and response to different systemic therapies. Compared to tumours arising in left colon, right colorectal cancers rely on the activation of different molecular pathways (e.g. BRAF mutation and MSI status). From a clinical point of view, this results in a different response to anti-EGFR agents. Current guidelines suggest the use of cetuximab or panitumumab in RAS wild-type disease and left colon cancer especially for cytoreduction/conversion purposes, since the expected benefit in right colon cancer is absent or clinically modest. The prognostic role of microbiota in colorectal cancer disease deserves more clarification before being considered in common clinical practice. Screening policies could also be affected by these new acquisitions. At the moment, sidedness should be considered as a strong prognostic variable and a surrogate predictor of different activity of anti-EGFR agents in the metastatic setting. Its role in early stages of resected disease is still uncertain.

Tumor Side as Model of Integrative Molecular Classification of Colorectal Cancer

It has long since been recognized that colorectal cancer is molecularly heterogeneous and its clinical behavior differs if the primary tumor was located in the right or left side of the colon. Recent studies have shown that part of this heterogeneity is captured by the anatomic location of the tumor. Clin Cancer Res; 24(5); 989-90. ©2017 AACRSee related article by Loree et al., p. 1062.

Polyp missing rate and its associated risk factors of referring hospitals for endoscopic resection of advanced colorectal neoplasia

Missed polyps are frequently observed in surveillance colonoscopy or referral resection. We evaluated the polyp missing rate and its associated risk factors in patients who were referred to a tertiary hospital for endoscopic resection of advanced colorectal neoplasia.A total of 388 patients with advanced neoplasia who underwent colonoscopy in their referring hospitals and only endoscopic resection without total colonoscopy in Pusan National University Yangsan Hospital from 2009 to 2014 and who underwent surveillance colonoscopy within 6 to 12 months were retrospectively analyzed.The per-patient missing rate for polyps, adenomas, and advanced neoplasia in referring hospital were 58.2% (226 cases), 47.2% (183 cases), and 5.7% (22 cases), respectively. The advanced neoplasia in surveillance colonoscopy comprised the following: ≥1 cm lesions (11 cases, 50%), high-grade dysplasia (4 cases, 18.2%), villous adenoma (4 cases, 18.2%), and invasive cancer (3 cases, 13.6%). Risk factors for missed adenomas in multivariate analysis were ≥60 years (P = .004), male (P <.001), and no usage of the cap-assisted colonoscopy (P = .015). Missed polyps/adenomas were most frequent in the ascending colon (P <.001).The missing rate for polyps/adenomas of referring hospitals was higher than expected. Especially, patients with old age or male, or no usage of cap-assisted colonoscopy on initial colonoscopy were at increased risk of missed adenoma. Careful complete colonoscopy during referral resection or early surveillance colonoscopy is mandatory in the patients with advanced colorectal neoplasia and unknown-quality index colonoscopy.

Colorectal and interval cancers of the Colorectal Cancer Screening Program in the Basque Country (Spain)

AIM

To assess proportions, related conditions and survival of interval cancer (IC).

METHODS

The programme has a linkage with different clinical databases and cancer registers to allow suitable evaluation. This evaluation involves the detection of ICs after a negative faecal inmunochemical test (FIT), interval cancer FIT (IC-FIT) prior to a subsequent invitation, and the detection of ICs after a positive FIT and confirmatory diagnosis without colorectal cancer (CRC) detected and before the following recommended colonoscopy, IC-colonoscopy. We conducted a retrospective observational study analyzing from January 2009 to December 2015 1193602 invited people onto the Programme (participation rate of 68.6%).

RESULTS

Two thousand five hundred and eighteen cancers were diagnosed through the programme, 18 cases of IC-colonoscopy were found before the recommended follow-up (43542 colonoscopies performed) and 186 IC-FIT were identified before the following invitation of the 769200 negative FITs. There was no statistically significant relation between the predictor variables of ICs with sex, age and deprivation index, but there was relation between location and stage. Additionally, it was observed that there was less risk when the location was distal rather than proximal (OR = 0.28, 95%CI: 0.20-0.40, P < 0.0001), with no statistical significance when the location was in the rectum as opposed to proximal. When comparing the screen-detected cancers (SCs) with ICs, significant differences in survival were found (P < 0.001); being the 5-years survival for SCs 91.6% and IC-FIT 77.8%.

CONCLUSION

These findings in a Population Based CRC Screening Programme indicate the need of population-based studies that continue analyzing related factors to improve their detection and reducing harm.

Use of the Endocuff during routine colonoscopy examination improves adenoma detection: A meta-analysis

AIM

To perform meta-analysis of the use of Endocuff during average risk screening colonoscopy.

METHODS

Scopus, Cochrane databases, MEDLINE/PubMed, and CINAHL were searched in April 2016. Abstracts from Digestive Disease Week, United European Gastroenterology, and the American College of Gastroenterology meeting were also searched from 2004-2015. Studies comparing EC-assisted colonoscopy (EAC) to standard colonoscopy, for any indication, were included in the analysis. The analysis was conducted by using the Mantel-Haenszel or DerSimonian and Laird models with the odds ratio (OR) to assess adenoma detection, cecal intubation rate, and complications performed.

RESULTS

Nine studies (n = 5624 patients) were included in the analysis. Compared to standard colonoscopy, procedures performed with EC had higher frequencies for adenoma (OR = 1.49, 95%CI: 1.23-1.80; P = 0.03), and sessile serrated adenomas detection (OR = 2.34 95%CI: 1.63-3.36; P < 0.001). There was no significant difference in cecal intubation rates between the EAC group and standard colonoscopy (OR = 1.26, 95%CI: 0.70-2.27, I2 = 0%; P = 0.44). EAC was associated with a higher risk of complications, most commonly being superficial mucosal injury without higher frequency for perforation.

CONCLUSION

The use of an EC on colonoscopy appears to improve pre-cancerous polyp detection without any difference in cecal intubation rates compared to standard colonoscopy.

Detection of early primary colorectal cancer with upconversion luminescent NP-based molecular probes

Early detection and diagnosis of cancers is extremely beneficial for improving the survival rate of cancer patients and molecular imaging techniques are believed to be relevant for offering clinical solutions. Towards early cancer detection, we developed a primary animal colorectal cancer model and constructed a tumor-specific imaging probe by using biocompatible NaGdF4:Yb,Er@NaGdF4 upconversion luminescent NPs for establishing a sensitive early tumor imaging method. The primary animal tumor model, which can better mimic the human colorectal cancer, was built upon continual administration of 1,2-dimethylhydrazine in Kunming mice and the tumor development was carefully monitored through histopathological and immunohistochemical analyses to reveal the pathophysiological processes and molecular features of the cancer microenvironment. The upconversion imaging probe was constructed through covalent coupling of PEGylated core-shell NPs with folic acid whose receptor is highly expressed in the primary tumors. Upon 980 nm laser excitation, the primary colorectal tumors in the complex abdominal environment were sensitively imaged owing to the ultralow background of the upconversion luminescence and the high tumor-targeting specificity of the nanoprobe. We believe that the current studies provide a highly effective and potential approach for early colorectal cancer diagnosis and tumor surgical navigation.

Impact of Colonoscopy Insertion Techniques on Adenoma Detection

BACKGROUND

Low adenoma detection rate (ADR) predicts development of interval cancers, found mainly in the right (cecum-ascending) colon, where poor bowel preparation is an associated factor. Single-site studies reported increased detection of adenomas in the proximal colon segments by water exchange (WE). Data about colon cleansing revealed that WE had the greatest impact in the right colon.

AIMS

To test the hypothesis that WE had the greatest impact on ADR in colon segments with the most favorable bowel cleanliness scores, namely the right colon.

METHODS

We pooled right colon and overall ADR data of three similarly designed colonoscopy trials that compared WE, water immersion (WI) and insufflation of air or carbon dioxide (AICD) in a mixed gender European population.

RESULTS

In this study, 1200 (704 males) subjects and were included. 288 were screening cases. Demographic and procedural data were comparable. Water exchange achieved significantly higher right colon <10 mm ADR (11.9 %, vs WI 6.9 %, p = 0.016; vs AICD 7.2 %, p = 0.025). Water exchange achieved the lowest proportions of poor bowel preparation and the highest right colon and overall Boston bowel preparation scale scores (p range 0.003, <0.0005). In patients with right colon excellent bowel cleanliness, water exchange was the only method significantly associated with right colon adenoma detection. One of the limitations is unblinded colonoscopists.

CONCLUSIONS

In a mixed gender European population, water exchange is confirmed to be a superior insertion technique showing a significant increase in <10 mm right colon adenoma detection, achieving the cleanest colon and lowest proportions of poor bowel preparation requiring repeat procedures. CLINICALTRIALS.

GOV NO

NCT01781650, 01954862, 01780818.

Insertion water exchange increases right colon adenoma and hyperplastic polyp detection rates during withdrawal

BACKGROUND

Single site studies in male Veterans in the U.S. reported increased detection of presumptive cancer precursors (adenomas, hyperplastic polyps) in the proximal colon (cecum-splenic flexure) by water exchange.

AIMS

Assess the reproducibility of the observation.

METHODS

Analysis of secondary outcomes collected prospectively in 3 similarly designed randomized controlled trials using water exchange, water immersion and insufflation (air or carbon dioxide).

MAIN OUTCOME

detection rates of adenomas and hyperplastic polyps in proximal, transverse and right colon (cecum-ascending).

RESULTS

704 males (173 screening) were evaluated. In the proximal colon, WE showed increased detection of small adenomas (p=0.009) and adenomas plus hyperplastic polyps (p=0.015) (vs insufflation); increased detection of adenomas plus hyperplastic polyps of any size (p=0.045) and of small size (p=0.04) (vs water immersion). In the right colon water exchange increased detection of small adenomas (19% vs 12.1%, p=0.04) (vs insufflation); small adenomas (19% vs 12%, p=0.038), adenomas plus hyperplastic polyps of any size (25% vs 16.7%, p=0.028) and of small size (23.7% vs 14.6%, p=0.012) (vs water immersion). Water exchange significantly improved bowel cleanliness. Sedation had no impact on lesion detection.

CONCLUSIONS

Water exchange is a superior insertion technique for detection of adenomas and hyperplastic polyps primarily in the right colon, especially those of small size.

Interval colorectal carcinoma: An unsolved debate

Colorectal carcinoma (CRC), as the third most common new cancer diagnosis, poses a significant health risk to the population. Interval CRCs are those that appear after a negative screening test or examination. The development of interval CRCs has been shown to be multifactorial: location of exam-academic institution versus community hospital, experience of the endoscopist, quality of the procedure, age of the patient, flat versus polypoid neoplasia, genetics, hereditary gastrointestinal neoplasia, and most significantly missed or incompletely excised lesions. The rate of interval CRCs has decreased in the last decade, which has been ascribed to an increased understanding of interval disease and technological advances in the screening of high risk individuals. In this article, we aim to review the literature with regard to the multifactorial nature of interval CRCs and provide the most recent developments regarding this important gastrointestinal entity.