Large Hyperplastic Polyps Research Articles

S5065 Co-Occurrence of Gastric Xanthoma and Numerous Large Hyperplastic Polyps as a Complication of Argon Plasma Coagulation in GAVE

S5065 Co-Occurrence of Gastric Xanthoma and Numerous Large Hyperplastic Polyps as a Complication of Argon Plasma Coagulation in GAVE

Patient and procedural factors associated with true histology rates in patients undergoing colonoscopy with computer-aided detection of polyps

Computer-aided detection (CADe) devices have been shown to increase adenoma detection rates and adenomas per colonoscopy compared to standard colonoscopies. Questions remain about whether CADe colonoscopies are mainly increasing the detection of small, nonneoplastic lesions or if they are detecting more pathologically meaningful polyps. In this analysis, we compare the true histology rate (defined as polyps with confirmation of clinically relevant histopathology) of CADe-identified polyps with polyps identified during standard colonoscopies. Using data from the SKOUT trial, we compared the true histology rate (THR) between CADe and standard colonoscopies. We also conducted a subgroup analysis by patient, procedural, and endoscopist factors. To account for multiple testing of comparisons, we used the false discovery rate. A total of 1423 participants were included (CADe, n= 714; standard, n= 709). Overall, THR was similar between the CADe and standard colonoscopy arms for adenomas, sessile serrated lesions, and large hyperplastic polyps. Higher THR with CADe colonoscopy was observed in some subgroups for adenomas. Endoscopists with 11 to 20 years of experience and procedures occurring after 12 pm had significantly higher adenoma THRs in the CADe cohort. Patients younger than 65 years, male patients, and procedures with a withdrawal time of≥8 minutes had borderline significance in the CADe device adenoma THR subgroup. CADe colonoscopies may hold the key to improving endoscopic quality measures, provided that the polyps identified by the CADe device are those of clinical relevance. Although the benefit and significance in the CADe group were demonstrated in this analysis, further research is warranted to ensure that the true histology is maintained when applied in real-world applications.

S3163 An Unusual Case of Upper GI Bleeding: Large Ulcerated Hyperplastic Gastric Polyp

S3163 An Unusual Case of Upper GI Bleeding: Large Ulcerated Hyperplastic Gastric Polyp

Local recurrence rates after resection of large colorectal serrated lesions with or without margin thermal ablation

Introduction Serrated lesions (SLs) including traditional serrated adenomas (TSA), large hyperplastic polyps (HP) and sessile serrated lesions (SSLs) are associated with high incomplete resection rates. Margin ablation combined with EMR (EMR-T) has become routine to reduce local recurrence while cold snare polypectomy (CSP) is becoming recognized as equally effective for large SLs. Our aim was to evaluate local recurrence rates (LRR) and the use of margin ablation in preventing recurrence in a retrospective cohort study. Methods Patients undergoing resection of ≥15 mm colorectal SLs from 2010-2022 were identified through a pathology database and electronic medical records search. Hereditary CRC syndromes, first follow-up > 18 months or no follow-up, surgical resection were excluded. Primary outcome was LRRs (either histologic or visual) during the first 18-month follow-up. Secondary outcomes were LRRs according to size, and resection technique. Results 191 polyps in 170 patients were resected (59.8% women; mean age, 65 years). The mean size of polyps was 22.4 mm, with 107 (56.0%) ≥20 mm. 99 polyps were resected with EMR, 39 with EMR-T, and 26 with CSP. Mean first surveillance was 8.2 mo. Overall LRR was 18.8% (36/191) (16.8% for ≥20 mm, 17.9% for ≥30 mm). LRR was significantly lower after EMR-T when compared with EMR (5.1% vs. 23.2%; p = 0.013) or CSP (5.1% vs. 23.1%; p = 0.031). There was no difference in LRR between EMR without margin ablation and CSP (p = 0.987). Conclusion The local recurrence rate for SLs ≥15 mm is high with 18.8% overall recurrence. EMR with thermal ablation of the margins is superior to both no ablation and CSP in reducing LRRs.

A72 LOCAL RECURRENCE RATES AFTER RESECTION OF LARGE COLORECTAL SERRATED LESIONS WITH OR WITHOUT MARGIN ABLATION

Abstract Background Endoscopic mucosal resection (EMR) has become the mainstay of therapy with regard to larger polyps. Serrated lesions (SLs) including traditional serrated adenomas (TSA), large hyperplastic polyps (HP) and sessile serrated lesions (SSLs) have been associated with high rates of incomplete resection. There has been an increasing role of margin ablation combined to EMR to reduce local recurrence. Purpose Our aim was to evaluate local recurrence rates (LRR) after resection of large colorectal SLs and the use of margin ablation in preventing recurrence Method Adult patients who underwent resection colorectal SSL, TSA, or HP polyps ≥ 15 mm from 2010-2019 with a colonoscopy follow-up within 18 months were identified through pathology database and electronic medical records search. Hereditary CRC syndromes, follow-ups longer than 18 months or no follow-up, surgical resection were excluded. The primary outcome was LRRs (either histologic or visual) during the first 18-month follow-up. Secondary outcomes were LRRs for polyps 15-19 mm and ≥20 mm, LRR after margin ablation for polyps ≥20mm. Result(s) Polyp resection was performed on 125 polyps in 112 patients (54.1 %women; mean age, 62.9 years). The mean size of polyps was 22.9 mm, with 58.4% ≥20mm. 76.0% of polyps were resected via EMR and 33.3% of polyps ≥20 mm received margin ablation. First surveillance colonoscopy was on average 8.4 months later and the resection scar was seen in 54.4% of lesions. Overall LRR for the first 18-months was 16% [95% confidence interval (CI) 10.5-23.6] (13% for polyps 15-19mm, 18% for ≥20mm, 22% for ≥30 mm). LRR for ≥20mm SLs was significantly lower after margin ablation (5.0% vs 24.0%; p=0.048). Conclusion(s) The local recurrence rate for SLs ≥15 mm is high with 16% overall recurrence, and increases with polyp size. Thermal ablation of the margins is superior to no ablation in reducing LRRs for ≥ 20mm SSLs. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

Prevalence of Metachronous Advanced Colorectal Neoplasia in Black and White Patients at a Safety Net Hospital.

Current postpolypectomy surveillance guidelines are based primarily on data from non-Hispanic Whites (NHWs); thus, generalizability to non-Hispanic Blacks (NHBs) remains unknown. Hence, the primary objective of this study was to assess the validity of these guidelines for NHBs by comparing the prevalence of metachronous advanced colorectal neoplasia (ACN) between NHWs and NHBs undergoing surveillance colonoscopy. This was a retrospective cross-sectional study of NHWs (N= 1500) and NHBs (N= 1260) aged 40-75 years who underwent surveillance colonoscopy at an academic safety net hospital between 2007 and 2017. The primary outcome measure was the prevalence of metachronous ACN, defined as an advanced adenoma, advanced sessile polyp, or invasive cancer. Multivariate logistic regression was used to measure associations between race/ethnicity and ACN prevalence after adjustment for potential confounding factors. Overall, the prevalence of metachronous ACN was similar for NHBs and NHWs (6.8% vs 7.4%, respectively; P= .60). The prevalence of metachronous cancers (0.2% vs 0.1%;P= .48), advanced adenomas (2.8% vs 3.8%; P= .14), advanced serrated polyps (3.5% vs 3.3%; P= .82), and large hyperplastic polyps ≥10mm (0.2% vs 0.6%, P= .24) were also similar between the 2 groups. Moreover, race was not a determinant of metachronous ACN after adjustment for age, sex, education, type of insurance, indication (screen/surveillance) for baseline colonoscopy, surveillance interval, and findings at baseline colonoscopy (adjusted odds ratio, 0.96; 95% confidence interval, 0.70-1.30; P= .78). Our study finds no significant difference in the prevalence of metachronous ACN between NHWs and NHBs undergoing appropriate postpolypectomy surveillance at an urban safety net hospital, suggesting that current guidelines are appropriate for both NHWs and NHBs.

S2937 Hyperplastic Gastric Polyps, “Size Matters”

INTRODUCTION: Hyperplastic gastric polyps are common incidental finding during EGD. They are usually asymptomatic but can present with iron deficiency anemia, gastric outlet obstruction and dysplasia especially when larger than one centimeter. CASE DESCRIPTION/METHODS: A 57-year old man without significant medical history was referred for iron deficiency anemia and occasional rectal bleeding for 1 year. His physical examination was unremarkable and family history was negative for malignancy or polyposis. Colonoscopy was normal. EGD revealed numerous large pedunculated polyps, as in Figures 1 and 2. They measured approximately 2 to 4 cm and stretched across the gastric lumen with a stalactite-like appearance. Some of the polyps were erythematous with small erosions and stigmata of recent bleeding. The polyps were removed with a hot snare over several endoscopy sessions. Pathology revealed hyperplastic polyps without dysplasia and negative stain for H. pylori. DISCUSSION: Hyperplastic polyps are equally common in men and women and typically occur in the sixth and seventh decades. They are usually found in the antrum and often are multiple. Large hyperplastic polyps often become lobulated and pedunculated, and the surface epithelium typically is eroded, which may result in chronic blood loss and iron deficiency anemia. The classic association of gastric hyperplastic polyps has been with mucosal atrophy, whether caused by H pylori infection or autoimmune gastritis. However, in recent years these polyps have increasingly been found in the background of a normal or reactive gastric mucosa without evidence of current or prior H pylori infection. Between 1% and 20% of hyperplastic polyps have been reported to harbor foci of dysplasia. Mutations of the p53 gene, chromosomal aberrations, and microsatellite instability all have been detected in these polyps. The overall prevalence of carcinoma in hyperplastic polyps is less than 2%, and it is more frequent in polyps larger than 2 cm. In view of the potential cancer risk, all hyperplastic polyps larger than 1 cm should be excised completely. Additionally, random biopsies from the intervening non-polypoid mucosa should be obtained. If present, H pylori should be eradicated and an endoscopic follow-up evaluation should be scheduled between 3 and 6 months after therapy to confirm successful eradication. The best intervals for such surveillance are unclear (e.g. annual, bi-annual, or some other interval) as is the number of years for which it should be continued.Figure 1Figure 2

Regression of a Large Hyperplastic Polyp after Helicobacter pylori Eradication Treatment

Regression of a Large Hyperplastic Polyp after Helicobacter pylori Eradication Treatment

Outcomes of Endoscopic Management of Large Gastric Hyperplastic Polyps

Risk factors for gastric hyperplastic polyps (GHPs) include chronic Helicobacter pylori infection, chronic atrophic gastritis, and cirrhosis. Despite

Risk of neoplastic change in large gastric hyperplastic polyps and recurrence after endoscopic resection.

Gastric hyperplastic polyps (GHPs) have a risk of neoplastic transformation reaching 5 %. Current endoscopic resection techniques appear suboptimal with a high risk of local recurrence. This study assessed the outcomes of endoscopic resection for GHPs and identified risk factors for recurrence and neoplastic transformation. This retrospective, multicenter, European study included adult patients with at least one GHP ≥ 10 mm who underwent endoscopic resection and at least one follow-up endoscopy. Patients with recurrent GHPs or hereditary gastric polyposis were excluded. All data were retrieved from the endoscopy, pathology, and hospitalization reports. From June 2007 to August 2018, 145 GHPs in 108 patients were included. Recurrence after endoscopic resection was 51.0 % (74 /145) in 55 patients. R0 resection or en bloc resection did not impact the risk of polyp recurrence. In multivariate analysis, cirrhosis was the only risk factor for recurrence (odds ratio [OR] 4.82, 95 % confidence interval [CI] 1.33 - 17.46; P = 0.02). Overall, 15 GHPs (10.4 %) showed neoplastic transformation, with size > 25 mm (OR 10.24, 95 %CI 2.71 - 38.69; P < 0.001) and presence of intestinal metaplasia (OR 5.93, 95 %CI 1.56 - 22.47; P = 0.01) being associated with an increased risk of neoplastic transformation in multivariate analysis. Results confirmed the risk of recurrence and neoplastic transformation of large GHPs. The risk of neoplastic change was significantly increased for lesions > 25 mm, with a risk of high grade dysplasia appearing in polyps ≥ 50 mm. The risk of recurrence was high, particularly in cirrhosis patients, and long-term follow-up is recommended in such patients.

3141 Large Gastric Hyperplastic Polyp as a Rare Cause of Iron Deficiency Anemia

INTRODUCTION: Gastric polyps are encountered in approximately 6% of endoscopic procedures. Most of the patients are asymptomatic, some of them can present with complications. We present a rare case of a large hyperplastic polyp resulting in iron deficiency anemia. CASE DESCRIPTION/METHODS: A 57 year-old man with past medical history of diabetes mellitus came in with complaints of 1 week history of dizziness, dyspnea on exertion and fatigue. Associated symptoms included persistent nausea and few episodes of non-bilious, non-bloody emesis. Patient denied melena or hematochezia. He endorsed weight loss of 8 lbs in 4 months. Vitals were grossly stable. Labs significant for Hb 6.7, Hct 23.8, and MCV 62. Patient was subsequently transfused with blood. Iron panel revealed severe iron deficiency with serum Iron 10, TIBC 443, Ferritin 4.6, Transferrin saturation 10. Colonoscopy was unremarkable however EGD revealed a large ulcerated polypoid mass, measuring about 10 to 15 cm in antrum concerning for early carcinoma. Pathology returned positive for hyperplastic polyp with no signs of dysplasia. Based on the large size of polyp, partial gastrectomy was done. On follow up, Hb increased and pt reported clinical improvement. DISCUSSION: Hyperplastic polyps constitute 75% of all the gastric polyps encountered. Hyperplastic polyps result from hyperplasia of epithelium secondary to chronic gastritis. Usually they range from 0.5 to 2 cm. About 1.4% of these polyps can reach a size large enough to cause iron deficiency anemia secondary to chronic bleeding. The risk of malignancy increases with size &gt;1 cm and require surgical resection. Yun et al reported a rare case of 1.5 cm hyperplastic polyp which was a cause of iron deficiency anemia. We describe a case of a large 10-15 cm hyperplastic polyp causing GI bleeding subsequently resulting in iron deficiency anemia. We recommend that physicians should be aware of this rare complication as polypectomy will benefit therapeutically in preventing future complications such as chronic bleeding.

1954 Hyperplastic Polyp: A Rare Case of Recurrent Iron Deficiency Anemia

INTRODUCTION: Hyperplastic polyps are the most common polyps accounting for 17% of all the gastric polyps. Most polyps are asymptomatic but may present with anemia, bleeding or gastric outlet obstruction. Here, we are reporting a case of large benign hyperplastic polyp presenting with iron deficiency anemia. CASE DESCRIPTION/METHODS: A 69-year-old male with a history of chronic back and neck pain and GERD was evaluated for chronic iron-deficiency anemia, treated multiple times with oral and IV iron supplements. The patient had been taking NSAIDs for chronic pain. On labs, patient hemoglobin of 9 with a low iron profile. The patient was scheduled for screening colonoscopy and EGD to further investigate anemia. On EGD patient had a large polypoid lesion about 25 mm in size in the prepyloric antrum extending into the duodenal bulb, likely cause of iron-deficiency anemia. There was also a small superficial clean-based ulcer on the antral lesion. Colonoscopy showed small internal hemorrhoids. Patient was discharged home on PPI and counseled to stop NSAIDs. Pathology report of the biopsies showed fragments of a benign hyperplastic polyp, negative for H pylori. The patient was afterward referred to interventional endoscopist for EUS and polyp excision. DISCUSSION: A hyperplastic gastric polyp is usually an incidental finding on upper endoscopy. With a prevalence of 6.35%, they are seen equally in elderly males and females in their 60s–70s. Hyperplastic polyps are believed to occur as a result of the reactive and inflammatory hyperproliferation of gastric foveolar cells, and Helicobacter pylori are believed to be the precursor. Diagnosis is usually made based on the results of endoscopy and subsequent biopsy of the suspicious area for the histological exam. On endoscopy, they appear as an area of hyperemia with a smooth dome-shaped surface, mostly in the antral area. As the size increases, they become pedunculated and the surface gets eroded resulting in chronic blood loss and anemia. Rarely, gastric outlet obstruction occurs when the large polyps prolapse though the pylorus. Since large polyps (&gt;2 cm) are associated with carcinoma in 0.6%–2% cases, it is important for the pathologist to look carefully for any dysplastic foci and carcinomatous changes in the tissue specimen. Once the diagnosis of hyperplastic polyp is confirmed, treatment consists of endoscopic resection of any polyp measuring &gt;1 cm in size and eradication of H.pylori, when present.

Diagnostic value of white light endoscopy and narrow band imaging for colorectal sessile serrated adenoma and hyperplastic polyp

Objective To differentiate colorectal sessile serrated adenoma (SSA) and large hyperplastic polyp (HP) with white light endoscopy and narrow band imaging. Methods Retrospective analysis was performed on the clinical data of 953 patients who underwent endoscopic screening for colorectal cancer at digestive endoscopy center of Peking Union Medical College Hospital from January 2015 to December 2015.Endoscopic features were compared with white light endoscopy and narrow band imaging between SSA and large HP in location, size, Paris classification, surface mucus, NICE classification and varicose microvascular vessel (VMV). Results A total of 28(2.9%) SSAs and 25(2.6%) HPs of diameter not less than 0.5 cm were detected in the total of 953 patients. Statistically significant difference was found in right hemi-colon, diameter not less than 1.0 cm and VMV in two groups(P<0.05). The sensitivities of the above three markers for SSA were 89.3%, 67.9% and 46.4% respectively. The specificities were 64.0%, 76.0% and 84.0% respectively. Diagnostic accuracies were 77.4%, 71.7% and 64.2% respectively. And the sensitivity, specificity and accuracy of three markers combined (at least two markers) were 75.0%, 88.0% and 81.1%, respectively. Conclusion SSA and large HP could be differentiated with a systemic consideration of lesion location, size, and surface of microvessels by using white light endoscopy and image-enhanced technique. Key words: Colonic polyps; Colonoscopy; Narrow band imaging; Sessile serrated adenoma; Hyperplastic polyp

Immunohistochemical and Molecular Features of Gastric Hyperplastic Polyps

1.1.Context:Gastric hyperplastic polyps are generally considered to be inflammatory lesions that develop in association with gastritis. Large polyps may contain foci of dysplasia, suggesting that they represent neoplasms, although molecular data regarding their pathogenesis are lacking. 1.2.Objective:To describe the clinical, pathologic, and molecular features of large (>1 cm) gastric hyperplastic polyps and compare them to those of small (≤1 cm) hyperplastic polyps and gastric adenomas. 1.3.Design:15 large hyperplastic polyps (>1 cm), including 4 with dysplastic foci, 10 small hyperplastic polyps (≤1 cm), and 9 gastric adenomas were evaluated for immunohistochemical expression of MGMT, MLH-1, β-catenin, p27, p16, and p53. Polyps with dysplasia or abnormal β-cateninexpression were assessed for APC and β-catenin (CTNNB1) mutations. Large hyperplastic polyps and adenomas were analyzed for KRAS and BRAF mutations. 1.4.Results:Complete loss of MGMT expression was significantly more frequent in large hyperplastic polyps (47%), often in combination with loss of p27 (47%), compared to adenomas (0% and 0%, p=0.02, respectively) and smaller lesions [0% (p=0.02) and 10% (p=0.09), respectively]. All non-dysplastic hyperplastic polyps showed preserved MLH1 and lacked nuclear β-catenin staining, but 3 with dysplasia had APC or β-catenin mutations. KRAS or BRAF mutations were detected in 20% of large hyperplastic polyps and 11% of adenomas. Most polyps were entirely negative for p16, although 6 (40%) large hyperplastic polyps and 3 (33%) adenomas showed expression in 10% p53 expression in the epithelium. Conclusion:Small gastric hyperplastic polyps are likely non-neoplastic, reparative lesions, but large polyps often show immunohistochemical and molecular abnormalities such as concomitant loss of MGMT with p27 staining, APC or β-cateninmutations in areas of dysplasia, and KRAS or BRAF mutations. These findings raise the possibility that some large hyperplastic polyps of the gastric mucosa represent early neoplasms.

Successful Treatment of a Rare Presentation of a Common Disease: Intense Proton Pump Inhibitor Therapy Regressed a Gastric Mass Due to Peptic Ulcer Disease

The worldwide annual incidence and prevalence of Peptic Ulcer Disease (PUD) has been reported to be 0.10-0.19% for both and causes dyspepsia in 10% of patients. The majority of PUD is caused by H. Pylori and NSAID use. It can be complicated by bleeding, perforation, penetration, and obstruction. Due to proton pump inhibitor (PPI) use and H. Pylori eradication, the prevalence of lesions seen in the gastroduodenal area has started to change. Gastric polyps have been reported in 4.8% of patients who had endoscopy. An 85-year-old female with a past medical history significant for hypertension, hyperlipidemia and diabetes who initially was admitted for headache, nausea and vomiting. Work-up with a CT head and MRI brain were negative. CT abdomen and pelvis showed a diffusely thickened stomach at the gastric body. Endoscopy showed a 4 by 7 cm antral and pre-pyloric mass that was excavated. The pylorus appeared deformed and was difficult to traverse with the endoscope. Upper GI series with small bowel follow through also revealed the mass in the gastric antrum along the greater curvature. Subsequently, she underwent an EUS that showed a large polypoid ulcerated mass extending from the greater curvature of the gastric body to the proximal duodenal bulb. The mass had irregular borders with invasion into the muscularis propria. It had 1.7 cm intramural thickness with endosonographic staging of T3N0Mx. Biopsies showed gastric mucosa with reactive and hyperplastic changes, negative for H. Pylori. She refused further intervention and opted for conservative management with Pantoprazole 40 mg two times a day. Repeat endoscopy in 3 months only showed a clean based 6 by 10 mm gastric ulcer in the stomach. Biopsies from ulcer edge showed hyperplastic foveolar epithelium with mild chronic inflammation. This patient presented with a gastric hyperplastic inflammatory mass in the setting of PUD. Hyperplastic polyps are seen in less than 20% of gastric polyps and classically are associated with H. Pylori, however, there has been increase in proportion of such polyps without concomitant H. Pylori infection. The prevalence of carcinoma is less than 2% among hyperplastic polyps which is more frequent in those larger than 2 cm. Common practice is to excise hyperplastic polyps larger than 1 cm. Studies have shown regression of small hyperplastic polyps after H. Pylori eradication. This case demonstrates a success story of treating a large gastric hyperplastic polyp with PPI.Figure 1Figure 2Figure 3

High Recurrence Rate of Large Hyperplastic Polyps After Endoscopic Resection

High Recurrence Rate of Large Hyperplastic Polyps After Endoscopic Resection

Gastric and Colonic Polyposis in a Patient Without Genetic or Hereditary Predisposition Presenting as Iron Deficiency Anemia

A 44 year-old female with no medical history presented with a 3-week history of melena. Labs revealed hemoglobin 8.5 g/dL, iron 16 ug/dL, and ferritin 5.3 ng/mL. Imaging noted large soft tissue densities of the stomach and multiple lesions in the right colon. EGD revealed a large (>15 cm), polypoid lesion extending from the fundus into the body and several large polyps in the cardia and antrum. Colonoscopy revealed large polyps at the cecum (5 cm), transverse (8 cm), and small (< 1 cm) polyps in the rectosigmoid. Gastric histology demonstrated hyperplastic polyps (HPP), and colonic biopsies revealed tubulovillous adenomas without dysplasia or malignancy. EUS of the gastric lesion showed areas of submucosal involvement without invasion of the muscularis propria, capsule endoscopy was negative for small bowel lesions. Genetic testing for polyposis syndromes was negative. Attempts at endoscopic debulking were unsuccessful, and a total gastrectomy and right hemicolectomy were performed. This case of diffuse gastric hyperplastic and colonic adenomatous polyposis represents a rare cause of iron deficiency anemia in a young patient. Few cases detailing both gastric and colonic polyposis in an individual with no hereditary predisposition are reported. HPP are the most common gastric polyps encountered. Reports demonstrate large HPP may have malignant potential similar to adenomas. HPP greater than 1 cm in size may indicate the presence of premalignant or neoplastic changes. In cases of diffuse gastric involvement, gastrectomy may be warranted as biopsies may be insufficient in detecting cancer. An association between gastric hyperplastic polyposis, carcinomas, and colonic neoplasms has been described. Hypergastrinemia has been postulated as a possible link between gastric polyposis and colorectal neoplasms due to the role of gastrin as a growth-promoting tumoral agent. Gastric adenomatous polyps increase the risk of colorectal neoplasia, however, information is limited regarding HPP and their risk. A recent study investigated the association of sporadic gastric HPP with colorectal neoplasia and found the risk of colorectal adenomas increased in patients with sporadic gastric hyperplastic polyposis. In our case, gastrectomy histology was consistent with hyperplastic polyps and colectomy histology showed foci of invasive adenocarcinoma. This case supports the notion for consideration of surveillance colonoscopy in patients with large or multiple gastric HPP.Figure 1Figure 2Figure 3

Risk of Metachronous Polyps in Individuals With Serrated Polyps.

Surveillance colonoscopy is recommended for patients with serrated polyps, but the risk of metachronous polyps is not well established. The aim of this study was to determine the risk of metachronous polyps in patients with serrated polyps and assess the relationship of coexistent adenomas in polyp recurrence. This prospective cohort study was conducted in a single tertiary center in the United States. Patients were included if they had a hyperplastic polyp ≥10 mm a sessile serrated polyp or a traditional serrated adenoma with or without coexistent adenomas, or only adenomas at baseline colonoscopy : The cumulative incidence of advanced adenomas and advanced serrated polyps was the primary outcome measured. The incidence of metachronous advanced adenomas was highest in patients with baseline advanced adenoma (40%) and 10% in those with serrated polyps only. The coexistence of serrated polyps and adenomas did not increase the risk of metachronous advanced adenoma (27% in serrated polyps + advanced adenoma and 7% in serrated polyps + nonadvanced adenoma). Metachronous serrated polyps ≥10 mm were seen exclusively in patients with baseline serrated polyps (serrated polyps only, 7%; serrated polyps + nonadvanced adenoma, 11%; serrated polyps +advanced adenoma, 9%) and not in patients with only adenomas at baseline. The small cohort and the data collected retrospectively were limitations of this study. Patients with baseline large hyperplastic polyps, sessile serrated polyps with or without dysplasia, or traditional serrated adenoma have a low risk of metachronous advanced adenoma, but were the sole group with recurrent large serrated polyps. No effect of coexistent serrated polyps and adenomas was seen for the recurrence of advanced adenoma.

Tu1731 Safe Definitive Endoscopic Management of High-Risk Polypoid Lesions of the Foregut Using Combined Volume Reduction and the Loop and Leave Technique

Large hyperplastic foregut polyps typically arise from chronically inflamed mucosa, present with bleeding or pain from prolapse, and have a <2% malignant potential. When malignancy is present, neoplasia is usually focal and lymph node involvement and metastases are rare. Due to the highly vascular nature of these polyps and low risk for malignancy, removal for histology is both dangerous and unnecessary in most cases, especially in those with comorbidities. Challenges include inability to fully encircle lesions to secure the stalks even with large snares, presence of thick stalks that cannot be clipped, and difficult positioning.

Multi-center colonoscopy quality measurement utilizing natural language processing.

An accurate system for tracking of colonoscopy quality and surveillance intervals could improve the effectiveness and cost-effectiveness of colorectal cancer (CRC) screening and surveillance. The purpose of this study was to create and test such a system across multiple institutions utilizing natural language processing (NLP). From 42,569 colonoscopies with pathology records from 13 centers, we randomly sampled 750 paired reports. We trained (n=250) and tested (n=500) an NLP-based program with 19 measurements that encompass colonoscopy quality measures and surveillance interval determination, using blinded, paired, annotated expert manual review as the reference standard. The remaining 41,819 nonannotated documents were processed through the NLP system without manual review to assess performance consistency. The primary outcome was system accuracy across the 19 measures. A total of 176 (23.5%) documents with 252 (1.8%) discrepant content points resulted from paired annotation. Error rate within the 500 test documents was 31.2% for NLP and 25.4% for the paired annotators (P=0.001). At the content point level within the test set, the error rate was 3.5% for NLP and 1.9% for the paired annotators (P=0.04). When eight vaguely worded documents were removed, 125 of 492 (25.4%) were incorrect by NLP and 104 of 492 (21.1%) by the initial annotator (P=0.07). Rates of pathologic findings calculated from NLP were similar to those calculated by annotation for the majority of measurements. Test set accuracy was 99.6% for CRC, 95% for advanced adenoma, 94.6% for nonadvanced adenoma, 99.8% for advanced sessile serrated polyps, 99.2% for nonadvanced sessile serrated polyps, 96.8% for large hyperplastic polyps, and 96.0% for small hyperplastic polyps. Lesion location showed high accuracy (87.0-99.8%). Accuracy for number of adenomas was 92%. NLP can accurately report adenoma detection rate and the components for determining guideline-adherent colonoscopy surveillance intervals across multiple sites that utilize different methods for reporting colonoscopy findings.