Clip Artifact after Closure of Large Colorectal Endoscopic Mucosal Resection Sites: Incidence and Recognition

Background Clip closure of large colorectal EMR defects sometimes results in bumpy scars that are normal on biopsy. We refer to these as “clip artifact.” If unrecognized, clip artifact can be mistaken for residual polyp, leading to thermal treatment and potential adverse events. Objective To describe the incidence of and define predictors of clip artifact. Design Review of photographs of scars from consecutive clipped EMR defects. Setting University outpatient endoscopy center. Patients A total of 284 consecutive patients with clip closure of defects after EMR of lesions 20 mm or larger and follow-up colonoscopy. Interventions EMR, clip closure. Main Outcome Measurements Incidence of clip artifact. Results A total of 303 large polyps met the inclusion criteria. On review of photographs, 96 scars (31.7%) had clip artifact. Clip artifact was associated with increased numbers of clips placed (odds ratio for each additional clip, 1.2; 95% confidence interval, 1.02-1.38) but not polyp histology, size, or location. The rate of residual polyp by histology was 8.9% (27/303), with 21 of 27 scars with residual polyp evident endoscopically. The rate of residual polyp evident only by histology in scars with clip artifact (3/93; 3.2%) was not different from the rate in scars without clip artifact (3/189; 1.6%). Limitations Retrospective design. Sites closed primarily with 1 type of clip. Single-operator assessment of endoscopic photographs. Conclusion Clip artifact occurred in the scars of approximately one-third of large clipped EMR sites and increased with number of clips placed. Clip artifact could be consistently distinguished from residual polyp by its endoscopic appearance

Recurrence rates after EMR of large sessile serrated polyps

Background Little is known regarding the recurrence rate after EMR of large (≥20 mm) sessile serrated adenoma/polyps (SSA/Ps). Objective To compare the recurrence rate among SSA/Ps and conventional adenomas in patients referred to a specialty practice for EMR. Design Retrospective cohort study. Setting Academic hospital and a satellite surgery center. Patients A total of 362 consecutive patients referred for resection of large (≥20 mm) polyps in the colorectum. Interventions All EMRs were performed with a submucosal contrast agent. All subjects had a follow-up surveillance examination (inspection and biopsy of the EMR) at our center. Main Outcome Measurements Rates of residual polyp at follow-up examination. Results Residual polyp was identified among 8.7% of SSA/Ps compared with 11.1% for conventional adenomas (P = .8). Limitations Retrospective design, procedures performed by a single experienced endoscopist, low number of serrated lesions. Conclusions The rate of recurrence after EMR of SSA/Ps is similar to the rate after EMR of conventional adenomas

A survey of patient acceptance of resect and discard for diminutive polyps

Background and Aims Resect and discard is a new paradigm for management of diminutive colon polyps. Little is known regarding whether patients would accept resect and discard. We surveyed colonoscopy patients and their drivers regarding acceptance of resect and discard. Methods This was a cross-sectional survey of colonoscopy outpatients and their drivers at two outpatient academic endoscopy centers. Results Four hundred fifteen colonoscopy patients and 293 drivers completed the survey (93.5% of all invited participants). Results for the two groups were similar. Overall, 66.3% indicated they would accept resect and discard. Participants who were younger, white, and seen at the ambulatory surgery center (vs the hospital outpatient department) were more likely to accept. Those declining resect and discard were more likely to be willing to pay some amount out-of-pocket to have diminutive polyps checked by pathology (97.1% vs 44.5%). Of those unwilling to accept resect and discard, 49.8% would require a zero chance of cancer in diminutive polyps before accepting resect and discard. Conclusions Patient acceptance of resect and discard appears promising but is quite variable. Eliciting individual patient acceptance of resect and discard will be important during initial implementation into clinical practice

The predictive value of small versus diminutive adenomas for subsequent advanced neoplasia

Background and Aims Patients with previous colorectal adenomas are at increased risk of colorectal cancer. Current guidelines for postpolypectomy surveillance intervals treat all tubular adenomas 1 to 9 mm in size with low-grade dysplasia as carrying the same level of risk. We evaluated whether 6 to 9 mm adenomas detected at colonoscopy are associated with greater risk of advanced neoplasia at follow-up compared with baseline 1 to 5 mm adenomas. Methods We retrospectively evaluated a colonoscopy database at a single U.S. academic center. Patients with baseline examinations demonstrating tubular adenomas 1 to 9 mm in size with low-grade dysplasia and no advanced adenomas were included. Follow-up colonoscopies were performed at least 200 days later and were assessed for incident advanced neoplasia (cancer, high-grade dysplasia, adenoma ≥10 mm in size, or villous elements). Results There were 2477 qualifying baseline colonoscopies. The absolute risk of metachronous advanced neoplasia increased from 3.6% in patients with 1 to 5 mm adenomas to 6.9% in patients with at least 1 adenoma of 6 to 9 mm (P = .001). Patients with 5 or more adenomas 1 of which was at least 6 to 9 mm had the highest risk of advanced neoplasia at follow-up (10.4%, P = .006). When only screening colonoscopies were considered, all baseline groups (1-2 adenomas, 3-4 adenomas, ≥5 adenomas) with adenomas 6 to 9 mm in size had an increased risk for metachronous advanced neoplasia (odds ratio [OR], 4.07; 95% confidence interval [CI], 1.50-11.04; OR, 4.91; 95% CI, 1.44-16.75; OR, 4.71; 95% CI, 1.30-17.05, respectively). Conclusions Patients with baseline small (6-9 mm) adenomas have an increased risk of advanced lesions on follow-up compared with patients with only diminutive (1-5 mm) adenomas. Postpolypectomy guidelines should consider risk stratification based on small versus diminutive adenomas

Regional center for complex colonoscopy: yield of neoplasia in patients with prior incomplete colonoscopy

Background and Aims Incomplete colonoscopy increases the risk of incident proximal colon cancer postcolonoscopy. Incomplete colonoscopy is often followed by barium enema or CT colonography. We sought to describe the yield of completion colonoscopy in a regional center for complex colonoscopy. Methods This is a retrospective cohort study of 520 consecutive patients referred to a single colonoscopist over a 14-year period for completion colonoscopy after a previous incomplete examination. Results Colonoscopy was completed to the cecum in 506 of 520 patients (97.3%). A total of 913 conventional adenomas was removed in 277 patients (adenoma detection rate 53.3%). There were 184 adenomas ≥ 1 cm in size or with advanced pathology. There were 525 serrated-class lesions removed in 175 patients, including 54 sessile serrated polyps in 26 patients and 41 hyperplastic polyps greater than 1 cm in 26 patients. Nine colorectal cancers were found. We estimated that approximately 57% of the conventional adenomas, 58% of the sessile serrated polyps, 27% of the hyperplastic polyps, and all 9 cancers detected by the completion colonoscopy were beyond the extent of the previous examination. Conclusions The yield of completion colonoscopy in a cohort of patients with previous failed cecal intubation was substantial. Regional centers for complex colonoscopy can provide high rates of cecal intubation in cases of incomplete colonoscopy and high yields of lesions in these cases. The regional center for complex colonoscopy is an important medical service

Long-Term Assessment of the Cecal Intubation Rates in High-Performing Colonoscopists: Time for Review

Objectives: The cecal intubation rate (CIR) is one of the 3 priority indicators for quality in colonoscopy. Whether continuous measurement of CIR is useful in high performers is uncertain. Methods: At an academic center, we identified 16 physicians who performed at least 50 procedures over 6 consecutive years. We analyzed all colonoscopy procedures excluding those with poor/inadequate preparation or severe colitis for CIR trend over the years. We calculated the numbers needed to establish CIR over minimum threshold levels with 95% confidence. Results: The overall CIR was 99.4%. None of the 16 physicians had a CIR 95%. Discussion: Continuous measurement of CIR, at least in high performers, appears to be of limited value. Very high performers need to evaluate small number of cases to demonstrate that CIR is above the recommended thresholds

Structure and absolute configuration of phenanthro-perylene quinone pigments from the deep-sea crinoid Hypalocrinus naresianus

Two new water-soluble phenanthroperylene quinones, gymnochrome H (2) and monosulfated gymnochrome A (3), as well as the known compounds gymnochrome A (4) and monosulfated gymnochrome D (5) were isolated from the deep-sea crinoid Hypalocrinus naresianus, which had been collected in the deep sea of Japan. The structures of the compounds were elucidated by spectroscopic analysis including HRMS, 1D 1H and 13C NMR, and 2D NMR. The absolute configuration was determined by ECD spectroscopy, analysis of J-couplings and ROE contacts, and DFT calculations. The configuration of the axial chirality of all isolated phenanthroperylene quinones (2–5) was determined to be (P). For gymnochrome H (2) and monosulfated gymnochrome A (3), a (2′S,2″R) configuration was determined, whereas for monosulfated gymnochrome D (5) a (2′R,2″R), configuration was determined. Acetylated quinones are unusual among natural products from an echinoderm and gymnochrome H (2) together with the recently reported gymnochrome G (1) represent the first isolated acetylated phenanthroperylene quinones

Determining the adenoma detection rate and adenomas per colonoscopy by photography alone: proof-of-concept study

Background and study aims: The adenoma detection rate (ADR) and adenomas detected per colonoscopy (APC) are measures of the quality of mucosal inspection during colonoscopy. In a resect and discard policy, pathologic assessment for calculation of ADR and APC would not be available. The aim of this study was to determine whether ADR and APC calculation based on photography alone is adequate compared with the pathology-based gold standard. Patients and methods: A prospective, observational, proof-of-concept study was performed in an academic endoscopy unit. High definition photographs of consecutive polyps were taken, and pathology was estimated by the colonoscopist. Among 121 consecutive patients aged ≥ 50 years who underwent colonoscopy, 268 polyps were removed from 97 patients. Photographs of consecutive polyps were reviewed by a second endoscopist. Results: The resect and discard policy applied to lesions that were ≤ 5 mm in size. When only photographs of lesions that were ultimately proven to be adenomas were included, the reviewer assessed ADR and APC to be lower than that determined by pathology (absolute reductions of 6.6 % and 0.17, and relative reductions of 12.6 % and 13.1 % in ADR and APC, respectively). When all photographs were included for calculation of ADR and APC, the reviewer determined the ADR to be 3.3 % lower (absolute reduction) and the APC to be the same as the rates determined by pathology. Conclusions: In a simulated resect and discard strategy, a high-level detector can document adequate ADR and APC by photography alone

Findings in the Distal Colorectum are not associated with Proximal Advanced Serrated Lesions

Background & Aims Serrated lesions are an important contributor to colorectal cancer (CRC), notably in the proximal colon. Findings in the distal colorectum are markers of advanced proximal adenomatous neoplasia. However, it is not known whether they affect the odds of advanced proximal serrated lesions. Methods We performed a retrospective cross-sectional study of data from 1910 patients (59.3 ± 8.0 years, 53.8% female) who underwent an average-risk screening colonoscopy from August 2005 through April 2012 at Indiana University Hospital and an associated ambulatory surgery center. Colonoscopies were performed by an endoscopist with high rates of detection of adenomas and serrated polyps. Tissue samples of all serrated polyps (hyperplastic, sessile serrated adenoma/polyp [SSA/P], or traditional serrated adenoma) proximal to the sigmoid colon and serrated polyps >5 mm in the rectum or sigmoid colon were reviewed by a gastrointestinal pathologist and reclassified on the basis of World Health Organization criteria. Advanced serrated lesion (ASL) was defined as SSA/P with cytologic dysplasia, SSA/P ≥10 mm, or traditional serrated adenoma. Advanced conventional adenomatous neoplasia (ACN) was defined as tubular adenoma ≥10 mm, villous histology, high-grade dysplasia, or cancer. The prevalence of proximal ASL and ACN was calculated on the basis of distal colorectal findings. Multivariable logistic regression analysis was performed to determine the age-adjusted and sex-adjusted odds of advanced proximal adenomatous and serrated lesions. Secondary analyses were performed to examine the effect of variable ASL definitions. Results Fifty-two patients (2.7%) had proximal ASL, and 99 (5.2%) had proximal ACN. Of the 52 patients with proximal ASL, 27 (52%) had no distal polyps. Of the 99 patients with proximal ACN, 40 (40%) had no distal polyps. Age and type of distal adenomas were significantly associated with proximal ACN. There were no significant associations between distal polyp type and proximal ASL. In secondary analyses, distal SSA/Ps (P = .008) but not distal hyperplastic polyps or conventional adenomas were associated with any proximal SSA/P. Conclusions The findings at flexible sigmoidoscopy that traditionally serve as indications for colonoscopy (conventional adenomas) are likely to be ineffective for detection of proximal ASL. This finding, plus the observation that most patients with proximal ASL have no distal polyps, favors screening colonoscopy over sigmoidoscopy, especially in the elderly. The observation that non-advanced distal SSA/Ps are associated with any proximal SSA/P warrants further study

Colorectal EMR outcomes in octogenarians versus younger patients referred for removal of large (≥20 mm) nonpedunculated polyps

Background and Aims Data are limited on safety and outcomes of colorectal EMR in octogenarians (≥80 years old). We sought to review outcome data for patients aged ≥80 in a prospectively collected database of patients referred for large polyp removal. Methods We retrospectively evaluated a database of patients referred for large (≥20 mm) nonpedunculated polyp removal. From 2000 to 2019, we compared the rates of follow-up, recurrence, adverse events, and synchronous neoplasia detection between younger patients and patients aged ≥80. Results There were 167 patients aged ≥80 years and 1686 <80 years. Patients in the elderly group returned for surveillance less often (67.1% vs 75.1%, P = .024), had greater first follow-up recurrence rates (27.5% vs 13.8%, P < .001), but had similar adverse event rates (1.8% vs 2.8%, P = .619) compared with younger patients. Rates of synchronous neoplasia were similar and high in both groups. Conclusions EMR is safe and well tolerated for large polyp removal in patients over 80 years old. Patients aged ≥80 years are less likely to present for follow-up after EMR. They had a higher recurrence rate and a similarly high prevalence of synchronous precancerous lesions. Follow-up after EMR should be encouraged in the elderly, and an attempt to clear the colon of synchronous disease at the time of the initial EMR may be warranted