Post-polypectomy colonoscopy surveillance: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

Low detection rate of advanced neoplasia within 5 years after polypectomy of small serrated adenoma

AIM

Patients with small serrated adenomas (SAs) (<10 mm) often undergo surveillance colonoscopy before the routine recommended time. We aimed to determine the appropriate surveillance intervals following polypectomy of small SAs for symptomatic patients.

METHOD

We retrospectively reviewed the data of 638 patients, including 122 cases and 516 controls. Subjects in the case group had small SAs at baseline colonoscopy, including sessile SA/polyps and traditional SAs, while subjects in the control group had negative findings. All patients underwent at least one surveillance colonoscopy during the following 5 years.

RESULTS

There was no significant difference in the incidence rate of advanced neoplasia between the two groups over a 5-year duration (3.6% vs 2.6%, p=0.455). Moreover, both groups also showed a low prevalence of SA formation over 1-5 years (3.6% vs 1.0%, p=0.145). Patients with baseline SA tended to undergo the first surveillance colonoscopy earlier than those without adenoma (≤1 year vs 1 to ≤3 years). Seventy-one (11.1%) of the total included subjects underwent inadequate initial colonoscopy, and 30 (42.3%) underwent early surveillance of adenoma formation within 1 year. Patients with a family history of colorectal cancer (OR 4.69, 95% CI 1.48 to 14.71, p=0.017) or inadequate baseline colonoscopy (OR 3.17, 95% CI 1.202 to 8.409, p=0.035) were at a higher risk of metachronous adenoma formation during the surveillance period.

CONCLUSION

Patients with small SAs at baseline gain little benefit from follow-up of colonoscopy within 5 years after complete polypectomy.

Non-guided self-learning program for high-proficiency optical diagnosis of diminutive and small colorectal lesions: A single-endoscopist pilot study

BACKGROUND

The implementation of optical diagnosis (OD) of diminutive colorectal lesions in clinical practice has been hampered by differences in performance between community and academic settings. One possible cause is the lack of a standardized learning tool. Since the factors related to better learning are not well described, strong evidence upon which a consistent learning tool could be designed is lacking. We hypothesized that a self-designed learning program may be enough to achieve competency in OD of diminutive lesions of the colon.

AIM

To assess the accuracy of OD of diminutive lesions in real colonoscopies after application of a self-administered learning program.

METHODS

This was a single-endoscopist prospective pilot study, in which an experienced endoscopist followed a self-designed, self-administered learning program in OD of colorectal lesions. An assessment phase divided in two halves with a 6-mo period in between without performance of OD was developed in a population-based colorectal cancer screening program. The accomplishment of the Preservation and Incorporation of Valuable Endoscopic Innovations criteria and performance measures were calculated overall and in the two halves of the assessment phase, assessing their response to the 6-mo stopping period. The evolution of performance through blocks of 50 lesions was also assessed.

RESULTS

Overall, 152 patients and 522 lesions (≤ 5 mm: 399, and 6-9 mm: 123) were included. The negative predictive value for the OD of adenoma in rectosigmoid lesions diagnosed with high confidence was 91.7% [95% confidence interval (CI): 87.3-96.6]. The proportion of agreement on surveillance interval between OD and pathological diagnosis was higher than 95%. Overall accuracy for diminutive lesions diagnosed with high confidence was 89.5% (95%CI: 86.3-92.7). The overall accuracy of OD was similar in the two halves of the assessment phase [90.1 (95%CI: 85.6-94.7) vs 88.2 (95%CI: 87.9-95.9)]. All the other performance parameters were also equivalent, except for specificity. Specificity, negative predictive value and accuracy were the parameters most affected by the stopping period between the two halves. Upon analyzing trends on blocks of 50 lesions, an improvement on sensitivity (P = 0.02) was detected only in the first half and an improvement on accuracy (P = 0.01) was detected only in the second half.

CONCLUSION

A self-administered learning program is sufficient to achieve expert-level OD. To maintain performance, continuous practice is needed, with a refresher course following any long non-practice period.

Five common errors to avoid in clinical practice: the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO) Choosing Wisely Campaign

Modern medicine provides almost infinite diagnostic and therapeutic possibilities if compared to the past. As a result, patients undergo a multiplication of tests and therapies, which in turn may trigger further tests, often based on physicians' attitudes or beliefs, which are not always evidence-based. The Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO) adhered to the Choosing Wisely Campaign to promote an informed, evidence-based approach to gastroenterological problems. The aim of this article is to report the five recommendations of the AIGO Choosing Wisely Campaign, and the process used to develop them. The AIGO members' suggestions regarding inappropriate practices/interventions were collected. One hundred and twenty-one items were identified. Among these, five items were selected and five recommendations were developed. The five recommendations developed were: (1) Do not request a fecal occult blood test outside the colorectal cancer screening programme; (2) Do not repeat surveillance colonoscopy for polyps, after a quality colonoscopy, before the interval suggested by the gastroenterologist on the colonoscopy report, or based on the polyp histology report; (3) Do not repeat esophagogastroduodenoscopy in patients with reflux symptoms, with or without hiatal hernia, in the absence of different symptoms or alarm symptoms; (4) Do not repeat abdominal ultrasound in asymptomatic patients with small hepatic haemangiomas (diameter < 3 cm) once the diagnosis has been established conclusively; (5) Do not routinely prescribe proton pump inhibitors within the context of steroid use or long-term in patients with functional dyspepsia. AIGO adhered to the Choosing Wisely Campaign and developed five recommendations. Further studies are needed to assess the impact of these recommendations in clinical practice with regards to clinical outcome and cost-effectiveness.

Risk of colorectal cancer for fecal immunochemistry test-positive, average-risk patients after a colonoscopy

BACKGROUND AND AIM

Because the risk of colorectal cancer has not been well examined in fecal immunochemistry test (FIT)-positive patients who previously underwent colonoscopy, this study aimed to investigate this topic.

METHODS

This was a single-center, observational study of prospectively collected data in Japan. FIT-positive, average-risk patients who underwent colonoscopy were divided into groups as follows: those who never underwent colonoscopy in the past (no colonoscopy group), those with a history of colonoscopy between 6 months and 5 years (0.5- to 5-year colonoscopy group), and those with a history of colonoscopy more than 5 years ago (> 5-year colonoscopy group). We investigated the prevalence of advanced neoplasia and invasive cancer among these groups using multiple logistic regression analysis.

RESULTS

Detection rates of advanced neoplasia in the no colonoscopy group, 0.5- to 5-year colonoscopy group, and > 5-year colonoscopy group were 14.8% (240/1626), 3.9% (13/330), and 6.9% (17/248), respectively. Detection rates of invasive cancer in each aforementioned group were 5.7% (92/1,626), 0.3% (1/330), and 1.2% (3/248), respectively. Odds ratios of advanced neoplasia in the 0.5- to 5-year colonoscopy group and > 5-year colonoscopy were 0.23 (95% confidence interval [CI]: 0.13-0.42) and 0.40 (95% CI: 0.24-0.68), respectively, in multivariate analysis. The odds ratios of invasive cancer in each aforementioned group were 0.05 (95% CI: 0.01-0.37) and 0.19 (95% CI: 0.06-0.61), respectively.

CONCLUSION

Re-screening with the FIT should not be recommended for at least 5 years for average-risk patients after colonoscopy without high-risk neoplasms, because the risks of colorectal cancer are low in such patients.

Blue-light imaging compared with high-definition white light for real-time histology prediction of colorectal polyps less than 1 centimeter: a prospective randomized study

BACKGROUND AND AIMS

Blue-light imaging (BLI) is a new chromoendoscopy technique, potentially useful for differentiating neoplastic from nonneoplastic lesions. The present study was aimed at comparing BLI with high-definition white light (HDWL) in the real-time histology prediction of colon polyps <10 mm.

METHODS

Consecutive outpatients undergoing colonoscopy with the ELUXEO 7000 endoscopy platform and 760 series video colonoscopes (Fujifilm Co, Tokyo, Japan) who had at least 1 polyp <10 mm were randomized to BLI or HDWL for polyp characterization. The accuracy of high-confidence real-time histology prediction (adenoma vs not adenoma) by either BLI or HDWL for polyps <10 mm (primary end-point) and diminutive (≤5 mm) polyps was calculated, along with sensitivity, specificity, and positive and negative predictive values, with histopathology as the reference standard.

RESULTS

A total of 483 polyps were detected in 245 randomized patients (125 and 120 in the BLI and HDWL arms, respectively). A total of 358 were diminutive, and 283 were adenomas. Overall, 222 (85.7%) and 193 (86.1%) polyps were characterized with high confidence by BLI and HDWL, respectively (P = .887), with an overall accuracy of 92% and 84%, respectively (P = .011). The accuracy was significantly higher by BLI than HDWL, also for diminutive polyps (92% vs 83%; P = .008). When BLI was used, the negative predictive value for diminutive rectosigmoid polyps was 88%, and the post-polypectomy surveillance interval was correctly attributed in 85.7% and 93.7% of patients, respectively, according to U.S. and European guidelines.

CONCLUSION

BLI was superior to HDWL for the real-time prediction of histology in polyps <10 mm. A BLI-dedicated classification might further improve the endoscopist performance. (Clinical trial registration number: NCT03274115.).

Role of Full-spectrum Endoscopy in Colorectal Cancer Screening: Randomized Trial

GOALS

The aim of this study was to compare a new, full-spectrum endoscope (Fuse; EndoChoice, Alpharetta, GA) to standard forward-viewing colonoscopy in the detection of colorectal neoplasms.

BACKGROUND

Colonoscopy, the gold standard for the detection of colorectal cancer, fails to detect 22% to 28% of polyps, increasing the risk of interval cancer. Endoscopic improvement of the adenoma detection rate decrease interval carcinomas. Full-spectrum endoscopy (FUSE) (330-degree field of view), in a tandem study, has been shown to reduce the adenoma miss rate.

STUDY

Prospective, randomized study of 249 patients in patients referred from the colorectal screening program with a positive fecal occult blood test (FOBT). Patients were randomized to standard forward-viewing colonoscopy (170 degrees) or to full-spectrum colonoscopy with the Fuse system (330 degrees). Study variables were the adenoma detection rate, the polyp detection rate, the mean number of adenomas per procedure, the lesions detected according to the location, morphology and size, cecal intubation rate, total procedure time, insertion time to the cecum, therapeutic success, and adverse events.

RESULTS

The Fuse system did not produce a significantly higher adenoma detection rate than standard forward-viewing colonoscopy (FUSE 73.1% vs. standard colonoscopy 68.1%; P=0.47) but did have a significantly longer insertion time (FUSE 6.2 min vs. standard colonoscopy 4.2 min; P< 0.001). Further analysis failed to reveal any significant difference in polyp/adenoma detection rates by lesion size or colonic section.

CONCLUSIONS

FUSE did not detect significantly more colorectal neoplasia than forward viewing colonoscopy in a medium-risk CRC screening population with positive FOBT.

Impact of a higher fecal immunochemistry test cut-off on pathology detected in subsequent rounds of a colorectal screening program

BACKGROUND AND AIMS

Fecal immunochemical test (FIT)-based colorectal cancer (CRC) screening is superior to the traditional binary fecal occult blood test. Its quantitative nature allows the investigator to choose a positivity threshold to match cost and endoscope capacity. The optimal threshold is still debated. BowelScreen, the Irish national colorectal cancer screening program, has a cut-off of 45 μg Hb/g feces, and in this study we investigated the impact of this threshold on pathology detected in round 2 in individuals who had a negative result for round 1 FIT (FIT¹).

METHODS

All individuals with a negative FIT¹ result who completed a round 2 FIT (FIT²) 2 years later were included. Pathology outcomes for individuals who had positive FIT² results were correlated with FIT¹ levels.

RESULTS

A total of 37,877 individuals had negative FIT¹ results and completed FIT². One thousand two hundred thirty (3.2%) had positive FIT² results (702 men [57%], median age 69, age range 60-70 years). Quantitative analysis showed that at an FIT¹ level <5 μg Hb/g feces, 2.3% had positive FIT² results. At a higher cut-off of 40.1 to 45 μg Hb/g feces, 15.6% of individuals had positive FIT² results. One thousand two (81.5%) underwent colonoscopy, with clinical outcomes in all cases. Three hundred fifty-one (35%) had normal colonoscopy results. The proportion of individuals with normal colonoscopy results decreased as FIT¹ levels rose. Conversely, advanced pathology (CRC + high-risk adenomas) rates rose from 7% to 50% when FIT¹ was <5 compared with 40.1 to 45 μg Hb/g feces, respectively. There were 51 screen-detected cancers in round 2 among individuals with negative FIT¹ results (22 stage I, 12 stage II, 14 stage III, 3 stage IV). All 3 stage IV individuals had FIT¹ results <20 μg Hb/g feces.

CONCLUSIONS

Varying rates of pathology are observed in round 2 of a screening program based on the quantitative level of a negative round 1 FIT result when the positivity threshold is relatively high. A CRC rate of 5.1% within this group appears acceptable. Although patients with incurable cancer were observed, the positivity threshold to capture these cases within round 1 would have been so sensitive that it would create an unsustainable endoscopy referral burden.

Diminutive Polyps With Advanced Histologic Features Do Not Increase Risk for Metachronous Advanced Colon Neoplasia

BACKGROUND & AIMS

With advances in endoscopic imaging, it is possible to differentiate adenomatous from hyperplastic diminutive (1-5 mm) polyps during endoscopy. With the optical Resect-and-Discard strategy, these polyps are then removed and discarded without histopathology assessment. However, failure to recognize adenomas (vs hyperplastic polyps), or discarding a polyp with advanced histologic features, could result in a patient being considered at low risk for metachronous advanced neoplasia, resulting in an inappropriately long surveillance interval. We collected data from international cohorts of patients undergoing colonoscopy to determine what proportion of patients are high risk because of diminutive polyps advanced histologic features and their risk for metachronous advanced neoplasia.

METHODS

We collected data from 12 cohorts (in the United States or Europe) of patients undergoing colonoscopy after a positive result from a fecal immunochemical test (FIT cohort, n = 34,221) or undergoing colonoscopies for screening, surveillance, or evaluation of symptoms (colonoscopy cohort, n = 30,123). Patients at high risk for metachronous advanced neoplasia were defined as patients with polyps that had advanced histologic features (cancer, high-grade dysplasia, ≥25% villous features), 3 or more diminutive or small (6-9 mm) nonadvanced adenomas, or an adenoma or sessile serrated lesion ≥10 mm. Using an inverse variance random effects model, we calculated the proportion of diminutive polyps with advanced histologic features; the proportion of patients classified as high risk because their diminutive polyps had advanced histologic features; and the risk of these patients for metachronous advanced neoplasia.

RESULTS

In 51,510 diminutive polyps, advanced histologic features were observed in 7.1% of polyps from the FIT cohort and 1.5% polyps from the colonoscopy cohort (P = .044); however, this difference in prevalence did not produce a significant difference in the proportions of patients assigned to high-risk status (0.8% of patients in the FIT cohort and 0.4% of patients in the colonoscopy cohort) (P = .25). The proportions of high-risk patients because of diminutive polyps with advanced histologic features who were found to have metachronous advanced neoplasia (17.6%) did not differ significantly from the proportion of low-risk patients with metachronous advanced neoplasia (14.6%) (relative risk for high-risk categorization, 1.13; 95% confidence interval 0.79-1.61).

CONCLUSION

In a pooled analysis of data from 12 international cohorts of patients undergoing colonoscopy for screening, surveillance, or evaluation of symptoms, we found that diminutive polyps with advanced histologic features do not increase risk for metachronous advanced neoplasia.

Thermal Ablation of Mucosal Defect Margins Reduces Adenoma Recurrence After Colonic Endoscopic Mucosal Resection

BACKGROUND & AIMS

Colorectal cancer (CRC) can be prevented by colonoscopy and polypectomy. Endoscopic mucosal resection (EMR) is performed to remove large laterally spreading colonic lesions that have a high risk of progression to CRC. Endoscopically invisible micro-adenomas at the margins of the EMR site might contribute to adenoma recurrence, which occurs in 15% to 30% of patients who undergo surveillance. We aimed to determine the efficacy of adjuvant thermal ablation of the EMR mucosal defect margin in reducing polyp recurrence.

METHODS

We performed a prospective study of 390 patients with large laterally spreading colonic lesions (≥ 20 mm, n = 416) referred for EMR at 4 tertiary centers in Australia. After complete lesion excision by EMR, lesions were randomly assigned to thermal ablation of the post-EMR mucosal defect margin (n = 210) or no additional treatment (controls, n = 206). We performed surveillance colonoscopies with standardized photo documentation and biopsies of the scar after 5 to 6 months. Patient, procedure, and lesion characteristics were similar between the groups. The primary endpoint was detection of lesion recurrence at first surveillance colonoscopy.

RESULTS

A significantly lower proportion of patients who received thermal ablation of the post-EMR mucosal defect margin had evidence of recurrence at first surveillance colonoscopy (10/192, 5.2%) than controls (37/176, 21.0%) (P < .001). The relative risk of recurrence in the thermal ablation group was 0.25 compared with the control group (95% confidence interval 0.13-0.48). Rates of adverse events were similar between the groups.

CONCLUSIONS

In a multicenter randomized trial, thermal ablation of the post-EMR mucosal defect margin significantly reduced polyp recurrence at first surveillance colonoscopy, compared with no additional treatment. Routine implementation of this simple and safe technique could increase the utility of EMR, decrease surveillance burdens, and reduce morbidity and mortality from CRC. ClinicalTrials.gov no: NCT01789749.

Impact of high-volume, intermediate-volume and low-volume bowel preparation on colonoscopy quality and patient satisfaction: An observational study

Background

Although optimal bowel preparation is essential for high-quality screening colonoscopy, documentation of preparation quality, patient satisfaction and adherence is scarce.

Aim

The aim of this article is to compare low-volume (LV, 300 ml sodium picosulfate), intermediate-volume (IV, 2 l polyethylene glycol, PEG + ascorbic acid and sodium ascorbate), and high-volume (HV, 4 l PEG) purgatives.

Results

A total of 5000 individuals (50.5% women) were enrolled between March 2015 and July 2017 (LV:IV:HV = 3.61:1.54:1). Overall sex- and age-adjusted adenoma detection rate was 25.4% (LV 23.8%, IV 25.4%, HV 29.8%), median age was 59.6 years, and cleansing was successful in 96.8%. Success rates of bowel cleansing were highest with HV (97.6%), followed by LV (97.2%) and IV (95.3%) with OR 2.04 (CI 95% 1.20-3.45, p = 0.008) and OR 1.79 (CI 95% 1.27-2.50, p = 0.001), respectively, compared to IV. A total of 93.5% of the LV group would use the same purgative in the future, 73.2% of IV and 69.4% of HV. A total of 84.4% would prefer overnight preparation, 12.1% same-day preparation.

Conclusion

All purgatives investigated showed good bowel cleansing quality results, patient satisfaction and compliance. Improvement in patient information might lead to even higher participation rates in screening colonoscopy since one in five patients stated that bowel preparation worried him or her most prior to colonoscopy.

Quality measures improving endoscopic screening of colorectal cancer: a review of the literature

INTRODUCTION

Colorectal cancer (CRC) is a major health-care problem all over the world and CRC screening is effective in reducing mortality and increasing the 5-year survival. Colonoscopy has a central role in CRC screening. It can be performed as a primary test, as a recall policy after a positive result of another screening test, and for surveillance. Since effectiveness of endoscopic screening depends on adequate detection and removal of colonic polyps, consistent quality measures, which are useful in enhancing the diagnostic yield of examination, are essential. Areas covered: The aim of this review is to analyze current evidence from literature supporting quality measures able to refine endoscopic screening of colorectal cancer. Expert commentary: Quality measures namely a) time slot allotted to colonoscopy, b) assessment of indication, c) bowel preparation, d) Cecal intubation, e) withdrawal time, f) adenoma detection rate, g) proper management of lesions (polypectomy technique, polyps retrieval rate and tattooing of resection sites), and h) adequate follow-up intervals play a key role in identifying malignant and at-risk lesions and improving the outcome of screening. Adherence to these quality measures is critical to maximize the effectiveness of CRC screening, as well as, a proper technique of colonoscopy and a quality report of the procedure. Among all recommended measures, adenoma detection rate is the most important and must be kept above the recommended quality threshold by all physicians practicing in the setting of screening.

Serrated Lesions of the Colon-Rectum: A Focus on New Diagnostic Tools and Current Management

Prompt diagnosis and correct management of the so called "serrated lesions" (SLs) of the colon-rectum are generally considered of crucial importance in the past years, mainly due to their histological heterogeneity and peculiar clinical and molecular patterns; sometimes, they are missed at conventional endoscopy and are possibly implicated in the genesis of interval cancers. The aim of this review is to focus on the diagnostic challenges of serrated lesions, underlying the role of both conventional endoscopy and novel technologies. We will show how an accurate and precise diagnosis should immediately prompt the most appropriate therapy other than defining a proper follow-up program. It will be emphasized how novel endoscopic techniques may provide better visualization of mucosal microsurface structures other than enhancing the microvascular architecture, in order to better define and characterize specific patterns of mucosal lesions of the gastrointestinal tract. Standard therapy of SLs of the colon-rectum is still very debated, also due to the relatively lack of studies focusing on treatment issues. The high risk of incomplete resection, together with the high rate of postcolonoscopy interval cancers, suggests the need of an extra care when facing this kind of lesions. Given this background, we will outline useful technical tips and tricks in the resection of SLs, taking aspects such as the size and location of the lesions, as well as novel available techniques and technologies, other than future perspectives, including confocal laser endomicroscopy into consideration. Follow-up of SLs is another hot topic, also considering that their clinical impact has been misunderstood for a long time. The incidence of the so called interval colorectal cancer underlines how some weaknesses exist in current screening and follow-up programs. Considering the lack of wide consensus for the management of some SLs, we will try to summarize and clarify the best strategies for their optimal management.

Cost-effectiveness analysis of postpolypectomy colonoscopy surveillance using Japanese data

OBJECTIVE

Recommendations vary on postpolypectomy surveillance, and no consensus has been reached even regarding the necessity of risk stratification based on polyp characteristics for surveillance. We examined an optimal postpolypectomy surveillance program by performing a cost-effectiveness analysis.

METHODS

We performed a Markov model analysis using parameters based on Japanese data and evaluated four postpolypectomy surveillance programs with respect to their effectiveness in terms of quality-adjusted life-years (QALYs), cost-effectiveness and required number of colonoscopies. Two were non-risk-stratified programs with 1-year (program 1) and 3-year (program 2) postpolypectomy surveillance colonoscopy, and the other two were risk-stratified programs. In program 3, surveillance colonoscopy was performed 3, 10 and 10 years after resection of advanced adenomas, low-risk adenomatous polyps, and no polyps, respectively. In program 4, those intervals were shortened to 1, 3 and 5 years, respectively.

RESULTS

Risk-stratified programs (3 and 4) yielded higher QALYs with lower costs than non-risk-stratified programs (1 and 2). Program 4 yielded higher QALYs (23.046) and lower required cost (107,717 JPY) than program 3. The required number of colonoscopies for program 4 was 1.2, 1.5 and 1.6 times that for programs 1, 2 and 3, respectively. A probabilistic sensitivity analysis showed that the probability of program 4 being chosen as the most cost-effective was highest.

CONCLUSIONS

After polypectomy, risk-stratified colonoscopy surveillance based on the polyp characteristics should be considered. A risk-stratified program with relatively short examination intervals could be effective and cost-effective in Japan, although further investigation and consideration of colonoscopy capacity are required.

Molecular profiling of longitudinally observed small colorectal polyps: A cohort study

BACKGROUND

Knowledge of the natural history of colorectal adenomas is limited because these lesions are removed upon detection. The few studies in which small adenomas have been left in situ for a limited period of time, have shown that most lesions remain stable or even completely regress. Specific DNA copy number changes ('cancer associated events' or CAEs) are associated with progression of adenomas to cancer. In this study we evaluated whether molecular features of progression correlated with growth of small polyps.

METHODS

Small (6-9 mm) colorectal precursor lesions detected on CT-colonography (CTC) were left in situ and re-evaluated with CTC after three years. Based on volumetric change, polyps were classified as either grown, stable or regressed. Surveillance CTC was followed by colonoscopy, during which all lesions were resected. Using DNA isolated from FFPE polyp tissues, low-coverage whole genome sequencing was performed to determine DNA copy number profiles, as well as target enrichment mutation analysis and CpG island methylation phenotype (CIMP) analysis. Expression of DNA mismatch repair (MMR) proteins was determined by immunohistochemistry. Samples were marked as MMR proficient if all MMR proteins were expressed.

FINDINGS

Out of 68 polyps resected at colonoscopy, for 65 (96%) material was available. Of these, 31 (48%) had grown, 27 (41%) remained stable and 7 (11%) regressed. Polyps with at least one CAE had higher growth rates compared to polyps without CAEs (difference 91% growth (95% CI 13-169), p = .023). CAEs were absent in lesions that had partially regressed. Mutations occurred in 94% of the polyps, with higher growth rates being associated with polyps having ≥2 mutations compared to lesions with only 0-1 mutations (difference 99% growth (95% CI 9-189), p = .032). All samples were MMR proficient. No relation between growth and CIMP was observed.

INTERPRETATION

Molecular alterations associated with colorectal cancer, correlated with growth of small polyps and were absent in polyps that regressed. Therefore, this longitudinal study provides in vivo support in the human setting for the functional role of these molecular alterations, that have mostly been identified by cross sectional observations in tissue samples of colorectal adenomas and cancers. FUND: Alpe d'Huzes- Dutch Cancer Society (project number NKI2013-6338).

High prevalence of advanced colorectal neoplasia and serrated polyposis syndrome in Hodgkin lymphoma survivors

Background

Hodgkin lymphoma (HL) survivors treated with abdominal radiotherapy and/or alkylating chemotherapy have an increased risk of colorectal cancer (CRC). This study was aimed at evaluating the prevalence of colorectal neoplasia in HL survivors.

Methods

This multicenter cohort study assessed the diagnostic yield of advanced colorectal neoplasia detected by a first surveillance colonoscopy among HL survivors treated with abdominal radiotherapy and/or procarbazine. Advanced colorectal neoplasia included advanced adenomas (high‐grade dysplasia, ≥25% villous component, or ≥10‐mm diameter), advanced serrated lesions (dysplasia or ≥10‐mm diameter), and CRC. The results were compared with those for a Dutch general population cohort that underwent a primary screening colonoscopy (1426 asymptomatic individuals 50‐75 years old). This study demonstrated the results of a predefined interim analysis.

Results

A colonoscopy was performed in 101 HL survivors, who were significantly younger (median, 51 years; interquartile range [IQR], 45‐57 years) than the general population controls (median, 60 years; IQR, 55‐65 years; P < .001). The prevalence of advanced neoplasia was higher in HL survivors than controls (25 of 101 [25%] vs 171 of 1426 [12%]; P < .001). Advanced adenomas were detected in 14 of 101 HL survivors (14%) and in 124 of 1426 controls (9%; P = .08). The prevalence of advanced serrated lesions was higher in HL survivors than controls (12 of 101 [12%] vs 55 of 1426 [4%]; P < .001). Serrated polyposis syndrome was present in 6% of HL survivors and absent in controls (P < .001).

Conclusions

HL survivors treated with abdominal radiotherapy and/or procarbazine have a high prevalence of advanced colorectal neoplasia. The implementation of a colonoscopy surveillance program should be considered.

Hodgkin lymphoma survivors treated with abdominal radiotherapy and/or procarbazine have a high prevalence of advanced colorectal neoplasia. The implementation of a colonoscopy surveillance program should be considered.

Management of local recurrence after endoscopic resection of neoplastic colonic polyps

A proportion of neoplastic polyps are incompletely resected, resulting in local recurrence, especially after resection of large polyps or piecemeal resection. Local recurrences that develop after endoscopic resection of intramucosal neoplasms that lacked risk factors for lymph node metastasis or positive vertical margins are usually treated endoscopically. Endoscopic submucosal dissection (ESD) is indicated for local residual or recurrent early carcinomas after endoscopic resection. However, ESD for such recurrent lesions is technically difficult and is typically a lengthy procedure. Underwater endoscopic mucosal resection (UEMR), which was developed in 2012, is suitable for recurrent or residual lesions and reportedly achieves superior en bloc resection rates and endoscopic complete resection rates than conventional EMR. However, a large recurrent lesion is a negative independent predictor of successful en bloc resection and of complete endoscopic removal. We therefore perform UEMR for relatively small (≤ 10-15 mm) recurrent lesions and ESD for larger lesions.

Risk of Metachronous Advanced Neoplasia in Patients With Multiple Diminutive Adenomas

OBJECTIVES

Individuals with advanced adenomas or three or more adenomas have a higher risk of metachronous advanced neoplasia (AN) and are recommended to undergo surveillance colonoscopy at shorter intervals. However, it is questionable whether patients with multiple (three or more) non-advanced diminutive adenomas should be considered as high-risk.

METHODS

We analyzed 5482 patients diagnosed with one or more adenomas during their first colonoscopy screening and who underwent a follow-up colonoscopy. Patients were categorized into four groups based on adenoma characteristics at baseline: Group 1, 1-2 non-advanced adenomas; Group 2, ≥3 non-advanced, diminutive (1 to 5 mm) adenomas; Group 3, ≥3 non-advanced, small (6-9 mm) adenomas; and Group 4, advanced adenomas.

RESULTS

During a median follow-up of 38 months, the incidence of metachronous AN at surveillance colonoscopy was 5.6%. The incidence of AN was 3.9% in group 1, 5.9% in group 2, 10.6% in group 3, and 22.1% in group 4. The adjusted hazard ratios (HRs) [95% confidence intervals (CIs)] for metachronous AN between group 2, group 3, and group 4, and low risk group 1 were 1.71 (0.99-2.94), 2.76 (1.72-4.44), and 5.23 (3.57-7.68), respectively. Compared with group 4, the adjusted HRs (95% CIs) for group 1, group 2, and group 3 were 0.19 (0.13-0.28), 0.32 (0.18-0.59), and 0.52 (0.31-0.89), respectively.

CONCLUSIONS

We found that patients with three or more non-advanced diminutive adenomas had a borderline increased risk of metachronous AN compared with patients with low risk adenomas.

Association between Cardiovascular Risk and Diabetes with Colorectal Neoplasia: A Site-Specific Analysis

Several studies have shown site-specific differences in colorectal cancer (CRC) with respect to the risk factors. CRC was shown to be associated with cardiovascular risk (CVR) factors, but site-specific variations have not been investigated so far. This study aimed to assess the associations between the prevalence and subsite-specific differences of colorectal neoplasia and established CVR scores or known coronary artery disease (CAD) in a large asymptomatic European screening cohort (N = 2098). Participants underwent simultaneous screening colonoscopy and CVR evaluation, using the Framingham Risk Score and Heart Score. Lesions found in the colonoscopy were classified by location (proximal/distal colon or rectum). More neoplasias were found in the proximal versus the distal colon (p < 0.001). The Framingham Risk Score and Heart Score showed incremental risk for colorectal adenoma, across the tertiles in the proximal and the distal colon (p < 0.001). The prevalence of adenomas in the rectum was much lower, but also here, incremental risk could be shown for the Framingham Risk but not the Heart Risk Score tertiles. Prevalence of adenomas in the proximal colon was higher in subjects with type 2 diabetes (T2DM) (p = 0.006), but no association was found between adenomas and T2DM in the distal colon (p = 0.618) and the rectum (p = 0.071). Males had a higher CVR and more findings, in the screening colonoscopy, as compared to females, however, no site-specific differences were noted. Patients with known CAD and high CVR have an increased risk of colorectal neoplasia in both the proximal and distal colon. Patients with T2DM have a higher risk for neoplasia in the proximal colon.

Genetic susceptibility in the development of colorectal adenomas according to family history of colorectal cancer

Our study aimed to evaluate the relevance of genetic susceptibility in the development of colorectal adenomas (CRA) and its relationship with the presence of family history of colorectal cancer (CRC). Genomic DNA from 750 cases (first degree relatives of patients with CRC) and 750 controls (subjects with no family history of CRC) was genotyped for 99 single nucleotide polymorphisms (SNPs) previously associated with CRC/CRA risk by GWAS and candidate gene studies by using the MassArray™ (Sequenom) platform. Cases and controls were matched by gender, age and histological lesion. Eight hundred and fifty‐eight patients showed no neoplastic lesions, whereas 288 patients showed low‐risk adenomas, and 354 patients presented high‐risk adenomas. Two SNPs (rs10505477, rs6983267) in the CASC8 gene were associated with a reduced risk of CRA in controls (log‐additive models, OR: 0.67, 95%CI:0.54–0.83, and OR:0.66, 95%CI:0.54–0.84, respectively). Stratified analysis by histological lesion revealed the association of rs10505477 and rs6983267 variants with reduced risk of low‐ and high‐risk adenomas in controls, being this effect stronger in low‐risk adenomas (log‐additive models, OR:0.63, 95%CI:0.47–0.84 and OR:0.64, 95%CI:0.47–0.86, respectively). Moreover, 2 SNPs (rs10795668, rs11255841) in the noncoding LINC00709 gene were significantly associated with a reduced risk of low‐risk adenomas in cases (recessive models, OR:0.22, 95%CI:0.06–0.72, and OR:0.08, 95%CI:0.03–0.61) and controls (dominant models, OR:0.50, 95%CI:0.34–0.75, and OR:0.52, 95%CI:0.35–0.78, respectively). In conclusion, some variants associated with CRC risk (rs10505477, rs6983267, rs10795668 and rs11255841) are also involved in the susceptibility to CRA and specific subtypes. These associations are influenced by the presence of family history of CRC.

What's new?

While numerous candidate gene variants have been associated with colorectal cancer, little is known about the relevance of genetic susceptibility or influence of family history in the development of precancerous colorectal adenomas. In the present study, certain genetic variants previously associated with colorectal cancer risk, including two variants in the CASC8 gene and two in the lnc‐RNA LINC00709 gene, were found to be also involved in susceptibility to colorectal adenomas. The associations were modified by family history of colorectal cancer. The results could have implications for colorectal cancer screening and the identification of individuals at increased risk of colorectal adenoma.

Quality indicators in colonoscopy. The colonoscopy procedure

The aim of the project this paper is part of was to propose quality and safety procedures and indicators to facilitate quality improvement in digestive endoscopy units. In this second issue, procedures and indicators are suggested regarding colonoscopy. First, a diagram charting the previous and subsequent steps of colonoscopy was designed. A group of experts in health care quality and/or endoscopy, under the auspices of the Sociedad Española de Patología Digestiva (SEPD), performed a qualitative review of the literature regarding colonoscopy-related quality indicators. Subsequently, using a paired-analysis method, the aforementioned literature was selected and analyzed. A total of 13 specific indicators were found aside of the common markers elsewhere described, ten of which are process-related (one pre-procedure, seven procedure, and two post-procedure markers) while the remaining three are outcome-related. Quality of evidence was assessed for each one of them using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) classification.

An evaluation of the SENTiFIT 270 analyser for quantitation of faecal haemoglobin in the investigation of patients with suspected colorectal cancer

BACKGROUND

An evaluation of SENTiFIT® 270 (Sentinel Diagnostics, Italy; Sysmex, Spain) analyser for the quantitation of faecal haemoglobin (f-Hb) was performed.

METHODS

The analytical imprecision, linearity, carry over and f-Hb stability were determined. Evaluation of the diagnostic accuracy was performed on 487 patients.

RESULTS

Within-run and between-run imprecision ranged 1.7%-5.1% and 3.8%-6.2%, respectively. Linearity studies revealed a mean recovery of 101.1% (standard deviation, 6.7%) for all dilutions. No carry over was detected below 7650 μg Hb/g faeces. Decay of f-Hb in refrigerated samples ranged 0.2%-0.5% per day. f-Hb in patients with advanced colorectal neoplasia (ACRN) (colorectal cancer [CRC] plus advanced adenoma [AA]) were significantly higher than from those with a normal colonoscopy. Sensitivity for ACRN at f-Hb cutoffs from 10 to 60 μg Hb/g faeces ranged from 28.9% (95% confidence interval [CI], 21.7%-37.2%) to 46.5% (95% CI, 38.1%-55%), the specificity ranged from 85% (95% CI, 82.3%-87.3%) to 93.2% (95% CI, 91.2%-94.8%), positive predictive values for detecting CRC and AA ranged from 11.6% (95% CI, 7.6%-17.2%) to 20.6% (95% CI, 13.3%-30.3%) and from 34.7% (95% CI, 28.1%-42%) to 42.3% (95% CI, 32.4%-52.7%), respectively, and the negative predictive value for ACRN ranged from 90.2% (95% CI, 87.9%-92.2%) to 88.4% (95% CI, 86%-90.4%). Using two samples per patient sensitivity increased with a slight decrease in specificity.

CONCLUSIONS

The analytical and clinical performances of SENTiFIT assay demonstrate a specific and accurate test for detecting ACRN in symptomatic patients and those undergoing surveillance.

Guideline Adherence to Colonoscopic Surveillance Intervals after Polypectomy in Korea: Results from a Nationwide Survey

Background/Aims

People around the world are increasingly choosing to undergo colorectal cancer screening via colonoscopy. As a result, guideline adherence to postpolypectomy colonoscopy surveillance has drawn increasing attention. The present study was performed to assess recognition and adherence to guidelines among primary care physicians and gastroenterologists and to identify characteristics associated with compliance.

Methods

A nationwide sample of primary care physicians employed at cancer screening facilities and registered members of the Korean Society of Gastrointestinal Endoscopy were recruited. Participants were asked to complete a survey of six hypothetical clinical scenarios designed to assess their potential course of action in response to screening or follow-up colonoscopy results. Frequencies and odds ratios and 95% confidence intervals for guideline adherence were estimated.

Results

The proportions of doctors recommending shortened colonoscopy surveillance intervals for low- and high-risk adenomas were greater than 90% among primary physicians and were much lower among gastroenterologists. Guideline adherence was relatively good among groups of doctors who were young, had a specialty in gastroenterology, worked at tertiary hospitals, and cared for an appropriate number of patients.

Conclusions

The present study reveals a remaining discrepancy between practitioner recommendations and current guidelines for postpolypectomy surveillance. Several factors were shown to be related to guideline adherence, suggesting a need for appropriate control and continuing education or training programs among particular groups of practitioners.

New-generation full-spectrum endoscopy versus standard forward-viewing colonoscopy: a multicenter, randomized, tandem colonoscopy trial (J-FUSE Study)

BACKGROUND AND AIMS

Although colonoscopy is the criterion standard for detection of colorectal adenomas, some adenomas are missed. Full-spectrum endoscopy (FUSE) allows for observation with a 330-degree angle of view, which is expected to decrease the miss rate. However, no consensus has been reached regarding the superiority of FUSE over standard forward-viewing colonoscopy (SFVC) for detection of adenomas; we therefore compared new-generation FUSE and SFVC regarding colorectal adenoma miss rate (AMR) in this, the first reported randomized control trial using new-generation FUSE.

METHODS

We enrolled individuals aged 40 to 75 years who had been referred for screening, surveillance, fecal occult blood test positivity, or symptoms in a prospective randomized trial of tandem colonoscopy in 8 institutions. Patients were randomly assigned (1:1) via computer-generated stratified randomization. Neither the endoscopists nor patients were blinded to the allocation. The primary endpoint was AMR per patient (AMR-PP).

RESULTS

We enrolled 345 patients and included 319 in the per-protocol analyses. AMR-PP was significantly lower with FUSE (11.7%; 95% confidence interval [CI], 8.0%-15.4%) than with SFVC (22.9%; 95% CI, 17.5%-28.3%; P < .001). AMR-PP for lesions ≤5 mm in size was significantly lower with FUSE (10.4%; 95% CI, 6.5%-14.3%) than with SFVC (20.0%; 95% CI, 14.4%-25.6%; P = .0057). Furthermore, AMR-PP in the ascending colon was significantly lower with FUSE (4.3%; 95% CI, 1.4%-7.2%) than with SFVC (10.6%; 95% CI, 6.1%-15.1%; P = .0212).

CONCLUSIONS

FUSE is superior to SFVC regarding both AMR-PP and AMR; additionally, AMR-PP is both significantly lower with FUSE than SFVC for lesions ≤5 mm in size and in the ascending colon. (Clinical trial registration number: UMIN000020448.).

Factors related to colorectal cancer in advanced adenomas and serrated polyps: a further step toward individualized surveillance

AIM

The risk of presenting synchronous or metachronous neoplasm, either adenoma or carcinoma, increases after an initial colonic lesion develops. It is known as tumor multicentricity and constitutes the rationale for surveillance programs. This study was designed to identify the clinical, pathologic, and molecular features related to previous or synchronous colorectal cancer (CRC) in patients with advanced adenomas (AA) or serrated polyps (SP).

PATIENTS AND METHODS

We carried out a prospective analysis of 4143 colonoscopies performed at our medical department between 1 September 2014 and 30 September 2015. Patients with AA/SP associated with previous or synchronous CRC are compared with patients with solitary AA/SP. We also performed immunohistochemical for the mismatch repair proteins in 120 AA or SP, 60 of them related to CRC.

RESULTS

Three-hundred and seventy-nine AA or SP were removed. Among these, 66 (17.3%) were associated with a previous (n=31) or synchronous CRC (n=35). Age older than or equal to 65 years (odds ratio: 1.15, 95% confidence interval: 1.05-1.26, P=0.002) and male sex (odds ratio: 2.13, 95% confidence interval: 1.3-3.49, P=0.003) were found to be independent predictive factors for CRC in patients with AA/SP by multivariate analysis. Only one of the 120 AA/SP available for immunohistochemical testing showed loss of staining and it was not related to CRC.

CONCLUSION

In patients with AA or SP, it is possible to identify a subgroup that is more likely to be associated with CRC and then prone to tumor multicentricity. These results have potential implications for establishing criteria for a more targeted surveillance.

Colonoscopy quality requisites for selecting surveillance intervals: A World Endoscopy Organization Delphi Recommendation

BACKGROUND AND AIMS

Different post-polypectomy guidelines underscore the need for high-quality baseline colonoscopy before appropriate surveillance recommendations can be made. Standards for colonoscopy practice have been advocated by gastrointestinal societies. Our aims were to define standards for the procedural practice of colonoscopy in this particular setting of surveillance and to generate a colonoscopy procedural quality checklist that could be implemented in clinical practice.

METHODS

This study was based on the Delphi process methodology. The baseline questionnaire included 12 domains and 56 individual statements. A total of three rounds were carried out between September 2015 and March 2016 until consensus or lack of consensus was reached.

RESULTS

In total, consensus was reached on 27 statements in nine domains. High levels of agreement and consensus were reached that: (i) colonoscopy should be considered complete only if the whole cecum has been inspected, including the ileocecal valve and the appendiceal orifice (agreement score 4.63; degree of consensus 82%); (ii) quality of the bowel preparation should always be reported (agreement score 4.9, degree of consensus 94%); and (iii) it is preferable to use a segmental validated scale (agreement score 4.36, degree of consensus 86%). Consensus was also reached regarding multiple statements related to documentation of polyps and their resection. Finally, a colonoscopy quality checklist was drafted.

CONCLUSION

Consensus on different statements regarding quality of colonoscopy has been reached. Based on this consensus, we propose a colonoscopy quality checklist that would be helpful for post-polypectomy surveillance recommendations.

Endoscopic submucosal dissection of 301 large colorectal neoplasias: outcome and learning curve from a specialized center in Europe

Background and study aims  Endoscopic submucosal dissection (ESD) allows en bloc resection of large colorectal lesions but ESD experience is limited outside Asia. This study evaluated implementation of ESD in the treatment of colorectal neoplasia in a Western center. Patients and methods  Three hundred and one cases of colorectal ESD (173 rectal and 128 colonic lesions) were retrospectively evaluated in terms of outcome, learning curve and complications. Results  Median size was 4 cm (range 1 - 12.5). En bloc resection was achieved in 241 cases amounting to an en bloc resection rate of 80 %. R0 resection was accomplished in 207 cases (69 %), RX and R1 were attained in 83 (27 %) and 11 (4 %) cases, respectively. Median time was 98 min (range 10 - 588) and median proficiency was 7.2 cm ² /h. Complications occurred in 24 patients (8 %) divided into 12 immediate perforations, five delayed perforations, one immediate bleeding and six delayed bleedings. Six patients (2 %), all with proximal lesions, had emergency surgery. Two hundred and four patients were followed up endoscopically and median follow-up time was 13 months (range 3 - 53) revealing seven recurrences (3 %). En bloc rate improved gradually from 60 % during the first period to 98 % during the last period. ESD proficiency significantly improved between the first study period (3.6 cm ² /h) and the last study period (10.8 cm ² /h). Conclusions  This study represents the largest material on colorectal ESD in the west and shows that colorectal ESD can be implemented in clinical routine in western countries after appropriate training and achieve a high rate of en bloc and R0 resection with a concomitant low incidence of complications. ESD of proximal colonic lesions should be attempted with caution during the learning curve because of higher risk of complications.

Clinical significance of colorectal polyp detection on colonoscopy insertion

Background

Colorectal lesions are generally evaluated during the withdrawal phase of colonoscopy. Minimising the risk of missed lesions is crucial to determine an appropriate future surveillance colonoscopy interval.

Objective

This study aimed to evaluate the clinical significance of detecting sigmoid colon lesions during the insertion phase.

Methods

This retrospective study included 172 consecutive patients undergoing colonoscopy between October 2017 and April 2018. The total number of detected polyps, mean polyps per procedure, mean polyps per positive procedure, and histological and clinical characteristics of detected lesions were recorded. The primary endpoint was the difference in sigmoid colon polyp detection rates during insertion and withdrawal.

Results

A total of 172 colonoscopies were performed for each patient and 322 lesions were detected. Sixty-two (19%) polyps were detected during insertion, 312 (97%) during withdrawal, and 52 (16%) during both insertion and withdrawal. Although all polyps except for those in the sigmoid colon could be detected during withdrawal, 10 of 87 (11%) polyps in the sigmoid colon could only be detected during insertion.

Conclusions

In this study, attempts to detect polyps, even in the insertion phase, showed the clinical significance to decrease the risk of missed adenomatous polyps in the sigmoid colon.

Self-Formation Assessed by Cumulative Summation Test Does Not Reach Recommended Thresholds for Optical Diagnosis of Colorectal Polyps ≤ 7 mm

BACKGROUND AND AIMS

Accurate optical diagnosis of diminutive polyps would allow implementing a resect and discard strategy. We evaluated the learning curve of a single training session followed by self-education in subjects with no endoscopic experience.

METHODS

Learning curves were evaluated in 38 subjects employing learning curve-cumulative summation (LC-CUSUM) tests, with each participant attending one training session regarding narrow band imaging and optical diagnosis and then individually assessing 100 lesions, receiving feedback after each diagnosis. Diagnostic accuracy was subsequently evaluated in 180 patients with lesions ≤ 7 mm. Evaluators predicted each polyp's histology and recommended a surveillance interval. Determinants of accuracy were explored using regression analysis.

RESULTS

According to the LC-CUSUM curve, 20 evaluators (52.6%) reached diagnostic competence after 57 lesions (IQR 55-76.5). During the diagnostic performance assessment, 11,666 diagnoses and 6840 follow-up recommendations were generated. Considering high confidence diagnoses, accuracy was 81.3% (80.5-82.1%), negative predictive value (NPV) for rectosigmoid adenomas 78.6% (76.4-80.6%), and sensitivity for adenomas 86.6% (85.8-87.4%). Two (5.3%) evaluators reached a ≥ 90% accuracy, 3 (7.9%) presented a NPV for rectosigmoid adenomas ≥ 90%, and 18 (47.4%) a sensitivity for adenomas ≥ 90%. Multivariable logistic regression showed high confidence and size ≥ 5 mm as the strongest predictors of accuracy. Fifteen (39.5%) evaluators recommended a correct or reduced follow-up interval in over 90% of subjects.

CONCLUSIONS

Self-formation after a single training session did not allow most evaluators to reach the required accuracy. LC-CUSUM tests did not identify competent evaluators. Despite these results, 86.7% of follow-up intervals would have been corrected or reduced.

Incidence and risk factors of advanced neoplasia after endoscopic mucosal resection of colonic laterally spreading lesions

PURPOSE

To investigate advanced neoplasia (AN) after endoscopic mucosal resection (EMR) of colonic laterally spreading lesions (LSLs).

METHODS

A retrospective study of patients who underwent injection-assisted EMR of colonic LSLs ≥ 10 mm was performed. Primary outcome was overall rate of AN at initial surveillance colonoscopy. Secondary outcomes were the rates of residual AN (rAN) at the EMR site and metachronous AN (mAN), and analysis of risk factors for AN, including effect of surveillance guidance.

RESULTS

Three hundred seventy-four patients underwent successful EMR for 388 LSLs. AN occurred in 66/374 (17.6%) patients on initial surveillance colonoscopy at median follow-up of 364.5 days. Two patients had both rAN and mAN, for a total of 68 instances of AN, including 30/374 (8.0%) cases of rAN and 38/374 (10.2%) cases of mAN. On multivariate analysis, use of piecemeal resection was associated with increased likelihood of residual AN (P = 0.003, OR 9.2, 95% CI 2.1-33.3). Twenty-nine out of thirty cases (96.7%) of rAN were successfully endoscopically managed at surveillance colonoscopy.

CONCLUSIONS

AN occurred in 17.6% of all patients at initial surveillance colonoscopy at a median of 1 year after EMR. Roughly half of the instances of AN were metachronous lesions. Our data support a 1-year surveillance interval after EMR of LSLs ≥ 10 mm with careful inspection of the entire colon, not just the prior resection site.

How long does it take until the effects of endoscopic screening on colorectal cancer mortality are fully disclosed?: a Markov model study

A recent randomized trial has suggested persisting protection from colorectal cancer (CRC) incidence and mortality of a single flexible sigmoidoscopy for up to 17 years and possibly beyond. We performed a simulation study to explore the time course and magnitude of protection provided by screening colonoscopy against CRC death over 25 years. Using data from the German national screening colonoscopy registry, a multistate Markov model was set up based on the adenoma-carcinoma pathway to estimate cumulative CRC mortality when different proportions of the population have a single screening colonoscopy at age 55, or two screening colonoscopies at ages 55 and 65. Cumulative CRC mortality continuously increased with age and reached 2.6 and 1.7% at age 80 in the absence of screening for men and women, respectively. A single colonoscopy at age 55, even with limited uptake, would lead to much lower cumulative mortality (0.7% for men and 0.5% for women at age 80 under 100% uptake). Relative mortality reduction continued to increase over more than 10 years and reached the maximum around 12-13 years after screening. Absolute risk reduction steadily increased throughout follow-up and more than half of the total risk reduction would occur between 15-25 years. A repeat colonoscopy 10 years later further enhanced the effects and cumulative mortality remained at 0.1-0.2% under 100% uptake. Even a single (once-only) screening colonoscopy has the potential to prevent most of CRC mortalities. Protective effects are expected to be long-lasting and to become fully manifest after more than two decades from screening.

Predicting the presence of adenomatous polyps during colonoscopy with National Cancer Institute Colorectal Cancer Risk-Assessment Tool

AIM

To evaluate the National Cancer Institute (NCI) Colorectal Cancer (CRC) Risk Assessment Tool as a predictor for the presence of adenomatous polyps (AP) found during screening or surveillance colonoscopy.

METHODS

This is a retrospective single center observational study. We collected data of adenomatous polyps in each colonoscopy and then evaluated the lifetime CRC risk. We calculated the AP prevalence across risk score quintiles, odds ratios of the prevalence of AP across risk score quintiles, area under curves (AUCs) and Youden’s indexes to assess the optimal risk score cut off value for AP prevalence status.

RESULTS

The prevalence of AP gradually increased throughout the five risk score quintiles: i.e., 27.63% in the first and 51.35% in the fifth quintile. The odd ratios of AP prevalence in the fifth quintile compared to the first and second quintile were 2.76 [confidence interval (CI): 1.71-4.47] and 2.09 (CI: 1.32-3.30). The AUC for all patients was 0.62 (CI: 0.58-0.66). Youden’s Index indicated the optimal risk score cutoff value discriminating AP prevalence status was 3.60.

CONCLUSION

Patients with the higher NCI risk score have higher risk of AP and subsequent CRC; therefore, measures to increase the effectiveness of CRC detection in these patients include longer withdrawal time, early surveillance colonoscopy, and choosing flexible colonoscopy over other CRC screening modalities.

Colorectal cancer screening program using FIT: quality of colonoscopy varies according to hospital type

Background and study aims  To compare the quality of colonoscopy in a population-based coordinated program of colorectal cancer screening according to type of hospital (academic or non-academic). Patients and methods  Consecutive patients undergoing colonoscopy after positive FIT (≥ 20 ug Hb/g feces) between January 2009 and September 2016 were prospectively included at five academic and seven non-academic public hospitals. Screening colonoscopy quality indicators considered were adenoma detection rate, cecal intubation rate, complications and bowel preparation quality. Results  A total of 48,759 patients underwent colonoscopy, 34,616 (80 %) in academic hospitals and 14,143 in non-academic hospitals. Among these cases, 19,942 (37.1 %) advanced adenomas and 2,607 (5.3 %) colorectal cancers (CRCs) were detected, representing a total of 22,549 (46.2 %) cases of advanced neoplasia. The adenoma detection rate was 64 %, 63.1 % in academic hospitals and 66.4 % in non-academic hospitals ( P  < 0.001). Rates of advanced adenoma detection, cecal intubation and adequate colonic preparation were 45.8 %, 96.2 % and 88.3 %, respectively, and in all cases were lower (implying worse quality care) in academic hospitals (45.3 % vs 48.7 %; odds ratio [OR] 0.87, 95 % confidence interval [CI] 0.84 - 0.91; 95.9 % vs 97 %; OR 0.48, 95 % CI 0.38 - 0.69; and 86.4 % vs 93 %; OR 0.48, 95 % CI 0.45 - 0.5; respectively; P  < 0.001 in all cases). In 13 patients, all in the academic hospital group, CRC was diagnosed after colonoscopy (0.26 cases × 1000 colonoscopies). Rates of CRC treated by endoscopy were similar in both types of hospital (30 %). The rate of severe complication was 1.2 % (602 patients), with no significant differences by hospital type: bleeding occurred in 1/147 colonoscopies and perforation in 1/329. One patient died within 30 days after screening colonoscopy. Conclusions  The quality of colonoscopy was better in non-academic hospitals. The rate of detection of advanced neoplasia was higher in non-academic hospitals and correlated with the rate of post-colonoscopy CRC.

World Endoscopy Organization Consensus Statements on Post-Colonoscopy and Post-Imaging Colorectal Cancer

BACKGROUND & AIMS

Colonoscopy examination does not always detect colorectal cancer (CRC)- some patients develop CRC after negative findings from an examination. When this occurs before the next recommended examination, it is called interval cancer. From a colonoscopy quality assurance perspective, that term is too restrictive, so the term post-colonoscopy colorectal cancer (PCCRC) was created in 2010. However, PCCRC definitions and methods for calculating rates vary among studies, making it impossible to compare results. We aimed to standardize the terminology, identification, analysis, and reporting of PCCRCs and CRCs detected after other whole-colon imaging evaluations (post-imaging colorectal cancers [PICRCs]).

METHODS

A 20-member international team of gastroenterologists, pathologists, and epidemiologists; a radiologist; and a non-medical professional met to formulate a series of recommendations, standardize definitions and categories (to align with interval cancer terminology), develop an algorithm to determine most-plausible etiologies, and develop standardized methodology to calculate rates of PCCRC and PICRC. The team followed the Appraisal of Guidelines for Research and Evaluation II tool. A literature review provided 401 articles to support proposed statements; evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. The statements were voted on anonymously by team members, using a modified Delphi approach.

RESULTS

The team produced 21 statements that provide comprehensive guidance on PCCRCs and PICRCs. The statements present standardized definitions and terms, as well as methods for qualitative review, determination of etiology, calculation of PCCRC rates, and non-colonoscopic imaging of the colon.

CONCLUSIONS

A 20-member international team has provided standardized methods for analysis of etiologies of PCCRCs and PICRCs and defines its use as a quality indicator. The team provides recommendations for clinicians, organizations, researchers, policy makers, and patients.

Variation between Pathological Measurement and Endoscopically Estimated Size of Colonic Polyps

Background and Aims

Accurate determination of colonic polyp size is vital to an appropriate surveillance. The main aim of this study was to evaluate variation between the polyp size reported by the endoscopist and its pathological measurement.

Methods

A retrospective analysis of all colonic adenomatous polyps resected in a 12-month period was performed at our center. Endoscopic and pathological size for each polyp were compared, and overestimation rates, underestimation rates, and endoscopic-pathological variation (EPV) were calculated.

Results

Among the 573 polyps that were included, the mean endoscopic and pathological sizes were 8.00 and 6.66 mm, respectively. The most frequent error, in 62.1%, was overestimation by the colonoscopist. Overestimation and EPV were associated with resection technique (higher in endoscopic mucosal resection and smaller with biopsy forceps) and colonoscopist. They were not associated with years of experience in colonoscopy. Overestimation was more frequent in larger polyps.

Conclusions

Our study shows significant discordance between endoscopic and pathological size of colonic polyps with a clear tendency for endoscopic overestimation. Larger polyps are more difficult to accurately assess than smaller ones. This propensity for error was not related to colonoscopist's years of experience and seems to be an individual tendency.

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.

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

BACKGROUND

The clinical significance of diminutive or small adenomas remains ill defined.

AIMS

We evaluated the clinical impact of diminutive or small adenomas at baseline on the risk of developing metachronous advanced colorectal neoplasia (CRN).

METHODS

This 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.

RESULTS

In 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.

CONCLUSIONS

Multiplicity of diminutive TAs, without advanced lesions, showed no clinical significance for risk of developing metachronous advanced CRN.

Clinical and endoscopic evaluations of sessile serrated adenoma/polyps with cytological dysplasia

BACKGROUND AND AIM

Although sessile serrated adenoma/polyps (SSA/Ps) are considered to be premalignant lesions and rapidly progress to carcinomas after they develop cytological dysplasia (CD), a treatment strategy for SSA/Ps in Asian countries is still being debated and has not yet been established. The present study aimed to propose a treatment strategy for SSA/Ps.

METHODS

Histopathological data of patients, who underwent colonoscopy at our center between January 2011 and December 2016, were reviewed. Data of patients with ≥ 1 SSA/P were retrieved, and clinicopathological characteristics were retrospectively analyzed.

RESULTS

A total of 281 patients with 326 SSA/Ps, including 258 patients who had 300 SSA/Ps without CD (SSA/Ps-CD[-]) and 23 patients who had 26 SSA/Ps with CD (SSA/Ps-CD[+]), were evaluated in this study. Although SSA/Ps-CD(+) were often found in older female patients and in the proximal colon, there were no significant differences between SSA/Ps-CD(-) and SSA/Ps-CD(+). Endoscopic morphological findings, such as large or small nodules on the surface and partial protrusion of the lesions, were significantly more common in SSA/Ps-CD(+) than in SSA/Ps-CD(-). Although the diagnostic ability of nodule/protrusion in lesions to predict CD within SSA/Ps was very high with an accuracy of 93.9% and a negative predictive value of 95.4%, sensitivity was low at 46.2%. SSA/Ps-CD(+) were significantly larger than SSA/Ps-CD(-), and the rate of CD within SSA/Ps significantly increased with lesion size (≤ 5 mm, 0%; 6-9 mm, 6.0%; ≥ 10 mm, 13.6%).

CONCLUSION

The study proposes removing all SSA/Ps ≥ 6 mm in order to remove high-risk SSA/Ps-CD(+), with high sensitivity.

Serrated neoplasia pathway as an alternative route of colorectal cancer carcinogenesis

In the past two decades, besides conventional adenoma pathway, a subset of colonic lesions, including hyperplastic polyps, sessile serrated adenoma/polyps, and traditional serrated adenomas have been suggested as precancerous lesions via the alternative serrated neoplasia pathway. Major molecular alterations of sessile serrated neoplasia include BRAF mutation, high CpG island methylator phenotype, and escape of cellular senescence and progression via methylation of tumor suppressor genes or mismatch repair genes. With increasing information of the morphologic and molecular features of serrated lesions, one major challenge is how to reflect this knowledge in clinical practice, such as pathologic and endoscopic diagnosis, and guidelines for treatment and surveillance.

Polypectomy techniques among gastroenterologists in Norway - a nationwide survey

BACKGROUND AND STUDY AIMS

 Incomplete polyp removal has been estimated to cause 27 % of all colorectal cancers detected soon after colonoscopy. There is limited information regarding polypectomy techniques among endoscopists. The article is a nationwide survey of polypectomy techniques among Norwegian endoscopists.

MATERIALS AND METHODS

 We invited all board-certified gastroenterologists in Norway to complete a web-based questionnaire about their polypectomy technique. Inadequate polypectomy techniques were defined as using biopsy forceps for polyps larger than 3 mm in diameter, using hot biopsy forceps for polypectomy, and using the same electrocautery output irrespective of polyp size and morphology.

RESULTS

Twenty-six of 30 Norwegian gastroenterology departments participated in the study. A total of 119 endoscopists received the survey, and 70 (59 %) responded. Mean duration of endoscopy practice was 11.5 years, and 95 % had performed more than 1,000 colonoscopies during their career. Twenty-eight endoscopists (40 %) used one or more inadequate polypectomy techniques: 10 (14.3 %) used biopsy forceps for removal of polyps larger than 3 mm in diameter, five (7.1 %) used hot biopsy for polypectomy, and 17 (24 %) used the same electrocautery output for all polypectomies. Five (7 %) endoscopists reported that they did not remove polyps smaller than 4 mm.

CONCLUSION

 A substantial number of Norwegian endoscopists use inadequate polypectomy techniques. Improved training and certification of endoscopists is warranted.

Sessile Serrated Adenomas: How to Detect, Characterize and Resect

Serrated polyps are important contributors to the burden of colorectal cancers (CRC). These lesions were once considered to have no malignant potential, but currently up to 30% of all CRC are recognized to arise from the serrated neoplasia pathway. The primary premalignant lesions are sessile serrated adenomas/polyps (SSA/Ps), although traditional serrated adenomas are relatively uncommon. Compared to conventional adenomas, SSA/Ps are morphologically subtle with indistinct borders, may be difficult to detect endoscopically, are more prevalent than previously thought, are associated with synchronous and metachronous advanced neoplasia, and have a higher risk of incomplete resection. Although many lesions remain “dormant,” progressive disease is associated with the development of dysplasia and more rapid progression to CRC. As a result, SSA/Ps are strongly implicated in the development of interval cancers. These factors represent unique challenges that require a meticulous approach to their management. In this review, we summarize the contemporary literature on the characterization, detection and resection of SSA/Ps.

Serum vitamin D levels correlate with the presence and histological grading of colorectal adenomas in peri and postmenopausal women

BACKGROUND & AIMS

Vitamin D is known to modulate immune function and proliferation. Higher vitamin D [25(OH)D₃] serum levels have been reported to have protective effects on adenoma detection and colorectal cancer (CRC) development and survival.

METHODS

This retrospective cohort study included 315 peri and post-menopausal women submitted to opportunistic colorectal and osteoporosis screening at the gynaecology outpatient clinic of a tertiary medical centre between 2004 and 2015. Colonoscopy findings were correlated with 25(OH)D₃ and PTH serum levels, and subsequently adjusted in a multivariate logistic regression model. Confounding factors included demographic and colorectal risk factors, pharmacological therapies and bone densitometry metrics.

RESULTS

A total of 77 lesions were identified in 66 patients. Vitamin D insufficiency (<30 ng/mL) and deficiency (<20 ng/mL) were identified in 79.4% and 35.2% of patients, respectively. In univariate analysis, lower levels of 25(OH)D₃ were associated with polyp, adenoma and advanced adenoma detection. After adjusting for confounders, an association with polyps could not be observed, but a trend towards a negative correlation with adenoma detection was found (adjusted OR: 0.96; 95% CI 0.92-1.00; p = 0.083). Regarding advanced adenoma detection, 25(OH)D₃ (adjusted OR: 0.86; 95% CI 0.77-0.97; p = 0.013) proved to be an independent predictive factor. No association was found between 25(OH)D₃ levels and lesion detection site.

CONCLUSION

The association of 25(OH)D₃ serum levels with colorectal lesions seems to be restricted to adenomatous lesions and is influenced by histological grading. Vitamin D may be a valuable biomarker for optimization of risk stratification in group-specific CRC screening protocols.

Back-to-back colon capsule endoscopy and optical colonoscopy in colorectal cancer screening individuals

AIM

The aim was to determine the polyp detection rate and per-patient sensitivity for polyps > 9 mm of colon capsule endoscopy (CCE) compared with colonoscopy as well as the diagnostic accuracy of CCE.

METHOD

Individuals who had a positive immunochemical faecal occult blood test during screening had investigator blinded CCE and colonoscopy. Participants underwent repeat endoscopy if significant lesions detected by CCE were considered to have been missed by colonoscopy.

RESULTS

There were 253 participants. The polyp detection rate was significantly higher in CCE compared with colonoscopy (P = 0.02). The per-patient sensitivity for > 9 mm polyps for CCE and colonoscopy was 87% (95% CI: 83-91%) and 88% (95% CI: 84-92%) respectively. In participants with complete CCE and colonoscopy examinations (N = 126), per-patient sensitivity of > 9 mm polyps in CCE (97%; 95% CI: 94-100%) was superior to colonoscopy (89%; 95% CI: 84-94%). A complete capsule endoscopy examination (N = 134) could detect patients with intermediate or greater risk (according to the European guidelines) with an accuracy, sensitivity, specificity and positivity rate of 79%, 93%, 69% and 58% respectively, using a cut-off of at least one polyp > 10 mm or more than two polyps.

CONCLUSION

CCE is superior to colonoscopy in polyp detection rate and per-patient sensitivity to > 9 mm polyps, but only in complete CCE examinations. The rate of incomplete CCE examinations must be improved.

Effects of Training and Feedback on Accuracy of Predicting Rectosigmoid Neoplastic Lesions and Selection of Surveillance Intervals by Endoscopists Performing Optical Diagnosis of Diminutive Polyps

BACKGROUND & AIMS

Real-time differentiation of diminutive polyps (1-5 mm) during endoscopy could replace histopathology analysis. According to guidelines, implementation of optical diagnosis into routine practice would require it to identify rectosigmoid neoplastic lesions with a negative predictive value (NPV) of more than 90%, using histologic findings as a reference, and agreement with histology-based surveillance intervals for more than 90% of cases.

METHODS

We performed a prospective study with 39 endoscopists accredited to perform colonoscopies on participants with positive results from fecal immunochemical tests in the Bowel Cancer Screening Program at 13 centers in the Netherlands. Endoscopists were trained in optical diagnosis using a validated module (Workgroup serrAted polypS and Polyposis). After meeting predefined performance thresholds in the training program, the endoscopists started a 1-year program (continuation phase) in which they performed narrow band imaging analyses during colonoscopies of participants in the screening program and predicted histological findings with confidence levels. The endoscopists were randomly assigned to groups that received feedback or no feedback on the accuracy of their predictions. Primary outcome measures were endoscopists' abilities to identify rectosigmoid neoplastic lesions (using histology as a reference) with NPVs of 90% or more, and selecting surveillance intervals that agreed with those determined by histology for at least 90% of cases.

RESULTS

Of 39 endoscopists initially trained, 27 (69%) completed the training program. During the continuation phase, these 27 endoscopists performed 3144 colonoscopies in which 4504 diminutive polyps were removed. The endoscopists identified neoplastic lesions with a pooled NPV of 90.8% (95% confidence interval 88.6-92.6); their proposed surveillance intervals agreed with those determined by histologic analysis for 95.4% of cases (95% confidence interval 94.0-96.6). Findings did not differ between the group that did vs did not receive feedback. Sixteen endoscopists (59%) identified rectosigmoid neoplastic lesions with NPVs greater than 90% and selected surveillance intervals in agreement with those determined from histology for more than 90% of patients.

CONCLUSIONS

In a prospective study following a validated training module, we found that a selected group of endoscopists identified rectosigmoid neoplastic lesions with pooled NPVs greater than 90% and accurately selected surveillance intervals for more than 90% of patients over the course of 1 year. Providing regular interim feedback on the accuracy of neoplastic lesion prediction and surveillance interval selection did not lead to differences in those endpoints. Monitoring is suggested, as individual performance varied. ClinicalTrials.gov no: NCT02516748; Netherland Trial Register: NTR4635.