995 Clinical Outcomes Following Incomplete Colonoscopy

Introduction Following incomplete colonoscopy (IC) it is reported that there is up to five-fold increased risk of colorectal cancer. Our aim was to determine the final clinical outcome for patients with a prior IC. Method A multi-centre retrospective observational study involving three endoscopy units. All consecutive patients having colonoscopy from over 18 months were analysed. Exclusion criteria included IC was due to obstructing cancer, follow up was not performed due to non-attendance at clinic or investigation and incomplete data set. Electronic notes were analysed to determine patient’s final clinical outcome. All patients were followed up for minimum of six months. Results Of the 8,490 colonoscopies, 733 (8.6%) were IC. 86 (11.7%) were excluded. Of the 647 included, 469 (72.4%) were females and 473 (73.1%) has further colonic investigations. Secondary investigations were: CT colonography 169 (35.7%), repeat colonoscopy 161 (34.0%), barium enema 95 (20.1%) and others 48 (10.1%). The repeat colonoscopy group achieved a complete colonoscopy in 111 (68.9%) patients. For those who had further investigations 15 (3.2%) had colorectal cancer and 12 (2.5%) has polyps ≥1cm. Conclusions There is significant risk of missing colorectal malignancy and large polyps following IC. Further colonic investigations should be carried out in this cohort of patients.

Sampling endoscopically normal large bowel mucosa from patients presenting with elevated faecal calprotectin levels is not clinically justified

Aims and methodsFaecal calprotectin (FCP) measurement is used especially to investigate for inflammatory bowel disease (IBD). To assess the utility of sampling endoscopically normal large bowel among patients first presenting with elevated FCP, this study identified 115 such patients out of 652 patients with elevated FCP from approximately 6000 primary care tests processed over 15 months.Results23 cohort patients showed histologically abnormal large bowel biopsies. Only four cases demonstrated acute inflammation and two such patients only showed scattered cryptitis and did not develop IBD. A third patient demonstrated similar histology but, following repeat colonoscopy, her elevated FCP was attributed to small intestinal inflammation. Only the fourth patient’s large bowel biopsies showed features suggesting Crohn’s disease, but this represented an IBD detection rate out of 115 sets of large bowel biopsies of 0.9%.ConclusionsSampling of endoscopically normal large bowel among patients first presenting with elevated FCP is not clinically justified.

Reducing Suboptimal Bowel Preparation

Achieving adequate bowel cleansing is essential to ensuring safe and effective colonoscopy. Yet, among hospitalized patients, suboptimal bowel preparation is a common problem leading to diagnostic delay, increased cost, and patient dissatisfaction. All patients, inpatient and outpatient, presenting with inadequate bowel preparation prior to procedure require repeat colonoscopy sooner than needed with successful bowel preparation.

Diagnostic yield of early repeat colonoscopy after suboptimal bowel preparation in a fecal immunochemical test-based screening program

Background Current guidelines regarding surveillance after screening colonoscopy assume adequate bowel preparation. However, follow-up intervals after suboptimal cleansing are highly heterogeneous. We aimed to determine the diagnostic yield of early repeat colonoscopy in patients with suboptimal bowel preparation in fecal immunochemical test (FIT)-based screening colonoscopy. Methods An observational study including patients who underwent colonoscopy with suboptimal bowel preparation after positive FIT screening and then repeat colonoscopy within 1 year. Suboptimal preparation was defined as a Boston Bowel Preparation Scale (BBPS) score of 1 in any segment. Patients with a BBPS score of 0 in any segment or incomplete examination were excluded. The adenoma detection rate (ADR), advanced ADR (AADR), and colorectal cancer rate were calculated for the index and repeat colonoscopies. Results Of the 2474 patients with FIT-positive colonoscopy at our center during this period, 314 (12.7 %) had suboptimal preparation. Of the 259 (82.5 %) patients who underwent repeat colonoscopy, suboptimal cleansing persisted in 22 (9 %). On repeat colonoscopy, the ADR was 38.7 % (95 %CI 32.6 % to 44.8 %) and the AADR was 14.9 % (95 %CI 10.5 % to 19.4 %). The per-adenoma miss rate was 27.7 % (95 %CI 24.0 % to 31.6 %), and the per-advanced adenoma miss rate was 17.6 % (95 %CI 13.3 % to 22.7 %). After repeat colonoscopy, the post-polypectomy surveillance recommendation changed from 10 to 3 years in 14.7 % of the patients with previous 10-year surveillance recommendation. Conclusions Patients with suboptimal bowel preparation on FIT-positive colonoscopy present a high rate of advanced adenomas in repeat colonoscopy, with major changes in post-polypectomy surveillance recommendations.

Post-polypectomy colonoscopy surveillance: European Society of Gastrointestinal Endoscopy (ESGE) Guideline – Update 2020

Main RecommendationsThe following recommendations for post-polypectomy colonoscopic surveillance apply to all patients who had one or more polyps that were completely removed during a high quality baseline colonoscopy. 1 ESGE recommends that patients with complete removal of 1 – 4 < 10 mm adenomas with low grade dysplasia, irrespective of villous components, or any serrated polyp < 10 mm without dysplasia, do not require endoscopic surveillance and should be returned to screening.Strong recommendation, moderate quality evidence.If organized screening is not available, repetition of colonoscopy 10 years after the index procedure is recommended.Strong recommendation, moderate quality evidence. 2 ESGE recommends surveillance colonoscopy after 3 years for patients with complete removal of at least 1 adenoma ≥ 10 mm or with high grade dysplasia, or ≥ 5 adenomas, or any serrated polyp ≥ 10 mm or with dysplasia. Strong recommendation, moderate quality evidence. 3 ESGE recommends a 3 – 6-month early repeat colonoscopy following piecemeal endoscopic resection of polyps ≥ 20 mm.Strong recommendation, moderate quality evidence. A first surveillance colonoscopy 12 months after the repeat colonoscopy is recommended to detect late recurrence.Strong recommendation, high quality evidence. 4 If no polyps requiring surveillance are detected at the first surveillance colonoscopy, ESGE suggests to perform a second surveillance colonoscopy after 5 years. Weak recommendation, low quality evidence.After that, if no polyps requiring surveillance are detected, patients can be returned to screening. 5 ESGE suggests that, if polyps requiring surveillance are detected at first or subsequent surveillance examinations, surveillance colonoscopy may be performed at 3 years. Weak recommendation, low quality evidence.A flowchart showing the recommended surveillance intervals is provided (Fig. 1).

A105 ENDOSCOPIC MUCOSAL RESECTION (EMR) OF LARGE SESSILE POLYPS: DATA FROM A MULTI-CENTER HEALTH ZONE

Background EMR is the standard of care for management of large non-invasive colonic polyps. Current guidelines recommend repeat colonoscopy within 6 months after EMR of large sessile polyps to assess the EMR site for residual adenoma. We reviewed the outcomes and compliance to these guidelines in patients at the University of Alberta Hospital (UAH) and surrounding 7 hospitals. Aims The primary outcome was the proportion of patients who received a follow up colonoscopy within 180 days. Methods Retrospective data was collected on consecutive patients who had a large polyp resection (size &gt;2cm as documented per endoscopy report) from January 1st, 2014 to January 1st, 2016. Information was collected on patients from UAH as well as seven surrounding hospitals within the Edmonton geographic zone. Data was extracted from electronic health records. Results Of 258 patients identified patients, 250 had complete data. Of these 250 patients, 151 (60.4 %) were male and median age was 67 (IQR 60 - 72). Eighty-two cases (32.8%) were performed at UAH, with 168 cases (67.2%) at other hospitals. Polyps were removed by gastroenterologists (n=215, 86.0%), surgeons (n=26, 10.4%), and others (n=9, 3.6%). Fifty-two patients (20.8%) had no formal follow up on electronic health records, while 198 patients (79.2%) had a repeat colonoscopy. 57 patients (29.1 %) had a repeat colonoscopy within 180 days. The median follow-up time was 224 days (IQR 172–365). Of the 82 cases performed at UAH, 74 (90.2%) had follow up. Out of the 168 cases at the other hospitals, 124 (73.8%) had follow up (p&lt;0.01). Sixteen (21.9%) and 41 (33.3%) cases were followed up within 180days at UAH and other hospitals, respectively (p=0.09). Of the 74 cases with follow up at UAH, 12 (15.7%) had residual tissue confirmed by pathology. Of the 124 cases at other hospitals, 26 (21.0%) had follow up (p=0.41). Median polyp size was 2.5cm (IQR 2.0cm - 3.5cm) Conclusions Only 29.1% of patients with large sessile polyp removal in the Edmonton zone had a repeat colonoscopy within 180 days. Patients with large polypectomy performed at the academic hospital were more likely to be followed up compared to non-academic hospitals. Further validation studies with larger data sets are needed. These findings highlight the need for standardized pathways to appropriately manage and survey large polyps post-EMR. Funding Agencies None

A Case of Langerhans Cell Histocytosis Masquerading as a Colon Polyp

Langerhans cell histocytosis, otherwise known as eosinophilic granuloma, is a rare neoplastic process composed of Langerhans cells and eosinophils. Most cases present during childhood, with the bones and skin being the most common organs involved. Other organs are occasionally involved, with some systemic cases involving the gastrointestinal tract. Presentations of Langerhans cell histocytosis range from single-organ involvement to systemic involvement. Fewer than five cases of isolated Langerhans cell histocytosis in the gastrointestinal system in adults have been reported. We present a case of Langerhans cell histocytosis incidentally discovered during routine colonoscopy in a 67-year-old otherwise healthy woman. Initial colonoscopy performed 7 years prior demonstrated a sessile serrated adenoma, fragments of tubular adenomas, and hyperplastic polyps. Repeat colonoscopy 3 years later demonstrated a sessile serrated adenoma and hyperplastic polyp. Upon repeat colonoscopy 4 years later, the patient had nine subcentimeter polyps. One of the ascending colon polyp fragments demonstrated a well-circumscribed, submucosal nodule of granular pink histocytes with folded to clefted and reniform nuclei. Numerous eosinophils were present in the background. These findings were consistent with Langerhans cell histocytosis. The remaining polyps were a tubular adenoma and hyperplastic polyps. A CT chest/abdomen/pelvis did not demonstrate any evidence of systemic disease. One year postdiagnosis, the patient had not had recurrence of symptoms. Unifocal Langerhans cell histocytosis rarely presents in the gastrointestinal tract of an adult and is believed to have a good prognosis with limited recurrence. The patient is being closely followed for development of systemic disease.