Traditional Serrated Adenomas Research Articles

Serrated Polyps in Inflammatory Bowel Disease Indicate a Similar Risk of Metachronous Colorectal Neoplasia as in the General Population.

The risk of metachronous advanced neoplasia after diagnosing serrated polyps in patients with IBD is poorly understood. A retrospective multicenter cohort study was conducted between 2010 and 2019 at three tertiary centers in Montreal, Canada. From pathology databases, we identified 1587 consecutive patients with serrated polyps (sessile serrated lesion, traditional serrated adenoma, or serrated epithelial change). We included patients aged 45-74 and excluded patients with polyposis, colorectal cancer, or no follow-up. The primary outcome was the risk of metachronous advanced neoplasia (advanced adenoma, advanced serrated lesion, or colorectal cancer) after index serrated polyp, comparing patients with and without IBD. 477 patients with serrated polyps were eligible (mean age 61years): 37 with IBD, totaling 45 serrated polyps and 440 without IBD, totaling 586 serrated polyps. The median follow-up was 3.4years. There was no difference in metachronous advanced neoplasia (HR 0.77, 95% CI 0.32-1.84), metachronous advanced adenoma (HR 0.54, 95% CI 0.11-2.67), and metachronous advanced serrated lesion (HR 0.76, 95% CI 0.26-2.18) risk. When comparing serrated polyps in mucosa involved or uninvolved with IBD, both groups had similar intervals from IBD to serrated polyp diagnosis (p > 0.05), maximal therapies (p > 0.05), mucosal inflammation, inflammatory markers, and fecal calprotectin (p > 0.05). The risk of metachronous advanced neoplasia after serrated polyp detection was similar in patients with and without IBD. Serrated polyps in IBD occurred independently of inflammation. This helps inform surveillance intervals for patients with IBD diagnosed with serrated polyps.

A survey of current practices in post-polypectomy surveillance in Korea.

We investigated the clinical practice patterns of post-polypectomy colonoscopic surveillance among Korean endoscopists. In a web-based survey conducted between September and November 2021, participants were asked about their preferred surveillance intervals and the patient age at which surveillance was discontinued. Adherence to the recent guidelines of the U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) was also analyzed. In total, 196 endoscopists completed the survey. The most preferred first surveillance intervals were: a 5-year interval after the removal of 1-2 tubular adenomas < 10 mm; a 3-year interval after the removal of 3-10 tubular adenomas < 10 mm, adenomas ≥ 10 mm, tubulovillous or villous adenomas, ≤ 20 hyperplastic polyps < 10 mm, 1-4 sessile serrated lesions (SSLs) < 10 mm, hyperplastic polyps or SSLs ≥ 10 mm, and traditional serrated adenomas; and a 1-year interval after the removal of adenomas with highgrade dysplasia, >10 adenomas, 5-10 SSLs, and SSLs with dysplasia. In piecemeal resections of large polyps ( > 20 mm), surveillance colonoscopy was mostly preferred after 1 year for adenomas and 6 months for SSLs. The mean USMSTF guideline adherence rate was 30.7%. The largest proportion of respondents (40.8%-55.1%) discontinued the surveillance at the patient age of 80-84 years. A significant discrepancy was observed between the preferred post-polypectomy surveillance intervals and recent international guidelines. Individualized measures are required to increase adherence to the guidelines.

Predicting Risk of Colorectal Cancer After Adenoma Removal in a Large Community-Based Setting.

Colonoscopy surveillance guidelines categorize individuals as high or low risk for future colorectal cancer (CRC) based primarily on their prior polyp characteristics, but this approach is imprecise, and consideration of other risk factors may improve postpolypectomy risk stratification. Among patients who underwent a baseline colonoscopy with removal of a conventional adenoma in 2004-2016, we compared the performance for postpolypectomy CRC risk prediction (through 2020) of a comprehensive model featuring patient age, diabetes diagnosis, and baseline colonoscopy indication and prior polyp findings (i.e., adenoma with advanced histology, polyp size ≥10 mm, and sessile serrated adenoma or traditional serrated adenoma) with a polyp model featuring only polyp findings. Models were developed using Cox regression. Performance was assessed using area under the receiver operating characteristic curve (AUC) and calibration by the Hosmer-Lemeshow goodness-of-fit test. Among 95,001 patients randomly divided 70:30 into model development (n = 66,500) and internal validation cohorts (n = 28,501), 495 CRC were subsequently diagnosed; 354 in the development cohort and 141 in the validation cohort. Models demonstrated adequate calibration, and the comprehensive model demonstrated superior predictive performance to the polyp model in the development cohort (AUC 0.71, 95% confidence interval [CI] 0.68-0.74 vs AUC 0.61, 95% CI 0.58-0.64, respectively) and validation cohort (AUC 0.70, 95% CI 0.65-0.75 vs AUC 0.62, 95% CI 0.57-0.67, respectively). A comprehensive CRC risk prediction model featuring patient age, diabetes diagnosis, and baseline colonoscopy indication and polyp findings was more accurate at predicting postpolypectomy CRC diagnosis than a model based on polyp findings alone.

Association between endoscopist adenoma detection rate and serrated polyp detection: Retrospective analysis of over 200,000 screening colonoscopies.

Background and study aims Serrated lesions have been identified as precursor lesions for 20% to 35% of colorectal cancers (CRCs) and may contribute to a significant proportion of interval-cancer. Sessile-serrated-lesions (SSLs), in particular, tend to be flat and located in the proximal colon, making their detection challenging and requiring expertise. It remains unclear whether the detection rate for serrated polyps should be considered as a quality indicator in addition to the adenoma detection rate (ADR). This study sought to assess whether the ADR has an effect on the detection rate for serrated polyps. atients and methods In this retrospective analysis, prospectively collected data from 212,668 screening colonoscopies performed between 2012 and September 2018 were included. Spearman correlation and Whitney-Mann U-test were used to assess the association of ADR and the detection rate of SSLs with (SDR) and without hyperplastic polyps (SPADRs), the sessile serrated detection rate (SSLDR) as well as the clinically relevant serrated detection rate (CRSDR), including all SSLs and traditional serrated adenoma, hyperplastic polyps (HPs) >10 mm anywhere in the colon or HPs > 5 mm proximal to the sigmoid. Results The overall mean ADR was 21.78% (standard deviation [SD] 9.27), SDR 21.08% (SD 11.44), SPADR 2.19% (SD 2.49), and CRSDR was 3.81% (3.40). Significant correlations were found between the ADR and the SDR, SPADR, SSLDR, and CRSDR (rho=0.73 vs. rho=0.51 vs. rho=0.51 vs. rho=0.63; all P <0.001). Endoscopists with a mean ADR ≥25% had significantly higher SDR, SPADR, and CRSDR than endoscopists with a mean ADR <25% (all P <0.001; Mann-Whitney U-Test). Conclusions This study shows that endoscopists with higher ADR detect significantly more serrated lesions than those with a lower ADR.

The histologic features, molecular features, detection and management of serrated polyps: a review.

The serrated pathway to colorectal cancers (CRCs) is a significant pathway encompassing five distinct types of lesions, namely hyperplastic polyps (HPs), sessile serrated lesions (SSLs), sessile serrated lesions with dysplasia (SSL-Ds), traditional serrated adenomas (TSAs), and serrated adenoma unclassified. In contrast to the conventional adenoma-carcinoma pathway, the serrated pathway primarily involves two mechanisms: BRAF/KRAS mutations and CpG island methylator phenotype (CIMP). HPs are the most prevalent non-malignant lesions, while SSLs play a crucial role as precursors to CRCs, On the other hand, traditional serrated adenomas (TSAs) are the least frequently encountered subtype, also serving as precursors to CRCs. It is crucial to differentiate these lesions based on their unique morphological characteristics observed in histology and colonoscopy, as the identification and management of these serrated lesions significantly impact colorectal cancer screening programs. The management of these lesions necessitates the crucial steps of removing premalignant lesions and implementing regular surveillance. This article provides a comprehensive summary of the epidemiology, histologic features, molecular features, and detection methods for various serrated polyps, along with recommendations for their management and surveillance.

Downregulation of SMOC1 is associated with progression of colorectal traditional serrated adenomas

BackgroundAberrant DNA methylation is prevalent in colorectal serrated lesions. We previously reported that the CpG island of SMOC1 is frequently methylated in traditional serrated adenomas (TSAs) and colorectal cancers (CRCs) but is rarely methylated in sessile serrated lesions (SSLs). In the present study, we aimed to further characterize the expression of SMOC1 in early colorectal lesions.MethodsSMOC1 expression was analyzed immunohistochemically in a series of colorectal tumors (n = 199) and adjacent normal colonic tissues (n = 112).ResultsSMOC1 was abundantly expressed in normal colon and SSLs while it was significantly downregulated in TSAs, advanced adenomas and cancers. Mean immunohistochemistry scores were as follows: normal colon, 24.2; hyperplastic polyp (HP), 18.9; SSL, 23.8; SSL with dysplasia (SSLD)/SSL with early invasive cancer (EIC), 15.8; TSA, 5.4; TSA with high grade dysplasia (HGD)/EIC, 4.7; non-advanced adenoma, 21.4; advanced adenoma, 11.9; EIC, 10.9. Higher levels SMOC1 expression correlated positively with proximal colon locations and flat tumoral morphology, reflecting its abundant expression in SSLs. Among TSAs that contained both flat and protruding components, levels of SMOC1 expression were significantly lower in the protruding components.ConclusionOur results suggest that reduced expression of SMOC1 is associated with progression of TSAs and conventional adenomas and that SMOC1 expression may be a biomarker for diagnosis of serrated lesions and risk prediction in colorectal tumors.

Biological background of colorectal polyps and carcinomas with heterotopic ossification: A national study and literature review

The biological mechanisms and potential clinical impact of heterotopic ossification (HO) in colorectal neoplasms are not fully understood. This study investigates the clinicopathological characteristics of colorectal neoplasms associated with HO and examines the potential role of the bone morphogenetic protein (BMP) pathway in development of HO. An artificial intelligence (AI) based classification of colorectal cancers (CRC) exhibiting HO and their association with consensus molecular subtypes (CMS) is performed.The study included 77 cases via the Dutch nationwide Pathology databank. Immunohistochemistry for BMP2, SMAD4, and Osterix was performed. An AI algorithm assessed the tumour-stroma ratio to approximate the CMS. A literature search yielded 96 case reports, which were analysed and compared with our cases for clinicopathological parameters.HO was more frequently observed in our cohort in traditional serrated adenomas (25%), tubulovillous adenomas (25%) and juvenile polyps (25%), while in the literature it was most often seen in juvenile polyps (38.2%) and inflammatory polyps (29.4%). In both cohorts, carcinomas were mostly conventional (>60%) followed by mucinous and serrated adenocarcinomas. Higher expression of BMP2, SMAD4, and Osterix was observed in tumour and/or stromal cells directly surrounding bone, indicating activation of the BMP pathway. The tumour-stroma analysis appointed >50% of the cases to the mesenchymal subtype (CMS4) (59%).HO has a predilection for serrated and juvenile/inflammatory polyps, mucinous and serrated adenocarcinomas. BMP signalling is activated and seems to play a role in formation of HO in colorectal neoplasms. In line with TGFβ/BMP pathway activation associated with CMS4 CRC, HO seems associated with CMS4.

A94 PRE-RESECTION OPTICAL EVALUATION RELIABLY DIFFERENTIATES BETWEEN SERRATED AND ADENOMATOUS LARGE NON-PEDUNCULATED COLORECTAL POLYPS

Abstract Background Modality selection between cold snare resection (CSR) and endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) is largely predicated on the ability to differentiate between serrated and adenomatous histopathology. While optical evaluation has modest accuracy for diminutive polyps, performance has not been evaluated for large non-pedunculated colorectal polyps (LNPCPs). Aims To evaluate the performance of pre-resection optical evaluation to differentiate between serrated and adenomatous LNPCPs. Methods Consecutive patients ampersand:003E 18 years of age who underwent endoscopic resection for a LNPCP were enrolled in a prospective single center observation cohort study (clinicaltrials.gov ID: NCT05402696). Pre-resection optical evaluation was performed using high-definition white-light and narrow-band imaging (NBI) with or without near-focus. The Japanese NBI Expert Team (JNET) classification was used to differentiate between serrated (JNET I) vs. adenomatous (JNET IIA, IIB) LNPCPs. Traditional serrated adenomas (TSAs) and cancers were excluded from analysis. Sensitivity, specificity, and accuracy were used to evaluate optical evaluation performance. Results From 06/2022-09/2023, 266 patients underwent 282 procedures for a total of 335 LNPCPs. Median size was 30mm (IQR 20-40mm). Histopathology identified 215 (64.2%) adenomatous, 91 (27.2%) serrated, 16 (4.8%) cancerous, and 13 (3.9%) other LNPCPs; including 5 TSAs. Of the 91 serrated lesions, 90 (98.9%) were predicted as serrated; sensitivity, specificity, and accuracy were 98.90% (95% CI 94.03-99.97), 99.53% (95% CI 97.44-99.99), 99.35% (95% CI 97.66-99.92), respectively. Of the 215 adenomatous lesions, 213 (99.1%) were predicted as adenomatous; sensitivity, specificity, and accuracy were 99.07% (95% CI 96.68-99.89), 98.90% (95% CI 94.03-99.97), 99.02% (95% CI 97.16-99.80), respectively. Conclusions Optical evaluation demonstrates excellent performance characteristics to differentiate between serrated and adenomatous LNPCPs; therefore, empowering endoscopists to reliably apply a selective resection algorithm between CSR, EMR and ESD. Funding Agencies None

A145 UNDERWATER EMR FOR LARGE FLAT DYSPLASTIC COLORECTAL LESIONS IN PATIENTS WITH CHRONIC ULCERATIVE COLITIS

Abstract Background Patients with chronic ulcerative colitis are at increased risk of colorectal cancer, in part due to increased prevalence of dysplastic lesions. To reduce CRC risk, endoscopic resection is preferable to surgery if feasible. However, large flat lesions can be challenging to remove endoscopically. We report our experience with underwater EMR for large, flat ulcerative colitis-associated dysplastic lesions. Aims To evaluate the safety and efficacy of UEMR for treatment of flat/sessile colorectal lesions with dysplasia, without overt signs of invasive cancer. To analyze rates of complications and outcomes for patients undergoing UEMR and compare to alternative methods of treatment for similar lesions. Methods We reviewed our IBD patient database from 2021 to 2023 for ulcerative colitis patients referred for large (≥ 20 mm diameter) flat/sessile colorectal lesions without overt signs of invasive cancer, who subsequently underwent underwater EMR. The procedure was performed by an endoscopist with extensive experience in UEMR for large colorectal lesions. Results Eleven de novo lesions in 8 patients (4 female; age 58 ± 14) were successfully treated with single-session UEMR. Mean lesion size was 42 ± 22 mm (range 20 to 80 mm); all morphologically flat (Paris IIa or IIb). Three cases were resected en bloc; the remainder piecemeal. Pathology showed tubulovillous adenoma, N=4 (36%); tubular adenoma, N=5 (45%); traditional serrated adenoma, N=1 (9%); sessile serrated lesion, N=1, (9%); high-grade dysplasia, N=1 (9%). There were no cases of invasive cancer. Endoscopic follow-up available for 5 patients over 10.4 ± 2 months showed benign diminutive recurrent/residual lesions in 2 cases, both amenable to UEMR. There were no procedural complications. Conclusions In this series of large, flat dysplastic CUC-associated lesions, UEMR was safe and effective, obviating surgery and endoscopic submucosal dissection. Funding Agencies None

Risk Factors Associated with Advanced Colorectal Neoplasia in Adults Younger than Age 45.

Colorectal cancer (CRC) is rising in young adults between ages 20 to 49 years. CRC screening is endorsed for average-risk individuals beginning at ages 45 to 49 years. Targeting screening for individuals <45 years may be warranted if risk factors for advanced neoplasia can be identified. To identify factors associated with advanced colorectal neoplasia in adults aged <45 years. Individuals ages 18 to 44 years who underwent colonoscopy at Cleveland Clinic between 2011 and 2021 with ≥1 advanced neoplasm (AN) were included. Patients with inflammatory bowel disease or inherited CRC syndromes were excluded. Demographics, comorbidities, family history of CRC, and colonoscopy indication were obtained. Patients with a normal colonoscopy constituted the control group. A multivariable logistic regression model was used to investigate the relationship between clinical variables and the presence of advanced colorectal neoplasia. In all, 13,006 patients were included, of which 651 (5%) patients had AN: 404 (62%) with tubular adenoma ≥10mm, 29 (4.5%) tubular adenoma with high-grade dysplasia, 210 (32%) tubulovillous adenomas, 27 (4%) traditional serrated adenomas, 82 (13%) sessile serrated lesions ≥10mm, 7(2%) sessile serrated lesions with dysplasia, and 29 (4.4%) patients had a CRC. Factors associated with AN were older age (means 38.5 vs. 36.6y), history of smoking, diabetes, non-White race, higher body mass index (29.9 vs. 28.5kg/m2), and lower vitamin D (27.6 vs. 32.2 ng/dl), all P<0.001. In the reduced multivariable model, factors associated with AN included tobacco use (OR 2.026 (current vs. never, P<0.0001), age (OR increase by 1.06 per year, P<0.0001), male gender (OR 1.476, P<0.0001), family history of CRC (OR 3.91, P<0.0001), aspirin use (1.31, P=0.035), and diabetes (OR 2.106, P 0.001). Increasing age, male gender, exposure to tobacco, family history of CRC, diabetes, and aspirin use were independently associated with advanced neoplasia in adults younger than 45. Targeted early screening to young adults with these risk factors may be justified. Large collaborative prospective studies are needed to validate our findings.

Serum DNA methylome of the colorectal cancer serrated pathway enables non-invasive detection.

The clinical relevance of the colorectal cancer serrated pathway is evident, but the screening of serrated lesions remains challenging. We aimed to characterize the serum methylome of the serrated pathway and to evaluate circulating cell-free DNA (cfDNA) methylomes as a potential source of biomarkers for the non-invasive detection of serrated lesions. We collected serum samples from individuals with serrated adenocarcinoma (SAC), traditional serrated adenomas, sessile serrated lesions, hyperplastic polyps and individuals with no colorectal findings. First, we quantified cfDNA methylation with the MethylationEPIC array. Then, we compared the methylation profiles with tissue and serum datasets. Finally, we evaluated the utility of serum cfDNA methylation biomarkers. We identified a differential methylation profile able to distinguish high-risk serrated lesions from no serrated neoplasia, showing concordance with tissue methylation from SAC and sessile serrated lesions. Serum methylation profiles are pathway-specific, clearly separating serrated lesions from conventional adenomas. The combination of ninjurin 2 (NINJ2) and glutamate-rich 1 (ERICH1) methylation discriminated high-risk serrated lesions and SAC with 91.4% sensitivity (64.4% specificity), while zinc finger protein 718 (ZNF718) methylation reported 100% sensitivity for the detection of SAC (96% specificity). This is the first study exploring the serum methylome of serrated lesions. Differential methylation of cfDNA can be used for the non-invasive detection of colorectal serrated lesions.

A Clinical-morphological Study of Colorectal Polyps with Emphasis on Serrated Lesions

Abstract Background: The World Health Organization introduced the entities of sessile serrated adenoma and traditional serrated adenoma, and hyperplastic polyps (HPs) under the serrated lesions category in 2010. Indian studies on demographic, clinical, and histopathological characteristics of colorectal polyps, especially on serrated lesions, are limited. Our study aimed to study the morphology of the colorectal polyps and estimate the percentage of serrated lesions in the polyps studied. Methodology: A cross-sectional hospital-based study was conducted on colorectal polyps received for routine histopathological examination from July 2013 to August 2015. The polyps were classified according to the WHO 2010 colon and rectum tumors classification. Data were compiled and analyzed using IBM SPSS statistics version 20.0. The interpretation was done in frequencies and percentages. Results: We studied a total of 200 colorectal polyps. The polyps were mostly seen in the descending colon (41%). Histologically, the majority of the colorectal polyps were adenomatous in nature (59%). The serrated lesions accounted for 29% of all colorectal polyps. The polyps were mostly seen in patients who were more than 40 years old. Conclusion: Adenomas were the most prevalent type of colorectal polyps, seen more in males, at a higher age, and distally located. Serrated lesions predominantly included HPs, mostly &lt;1 cm in size.

Serrated Polyposis Syndrome: A Literature Review

AbstractSerrated polyposis syndrome is considered the most prevalent colonic polyposis syndrome in the world. Its importance has been increasingly discussed due to the significant increase in the risk of developing colorectal cancer in its affected individuals, similarly to other well-known polyposis syndromes, such as familial adenomatous polyposis.Serrated lesions of the colon play a major role in this syndrome represented by hyperplastic polyps, serrated sessile lesions and traditional serrated adenomas. Among these lesions, the sessile serrated lesion stands out, considered the main precursor lesion of the serrated pathway of colon carcinogenesis.Diagnosis of serrated polyposis syndrome is given through colonoscopy examination. Diagnostic criteria are: 1) 5 or more serrated lesions proximal to the rectum, all &gt;4mm in size, with at least two &gt;9mm in size; or 2) 20 serrated lesions of any size located anywhere in the large intestine, with &gt;4 lesions proximal to the rectum.The ideal treatment is removal of all relevant serrated lesions by colonoscopy. In case of failure of endoscopic therapy, surgery is indicated. This manuscript is based on two case reports and a literature review and aims to broaden the discussion about the subject.

Strategy for post-polypectomy colonoscopy surveillance: focus on the revised Korean guidelines

Background: The risk of metachronous advanced neoplasia is linked to the presence of polyps on initial colonoscopy. Consequently, it is crucial to establish an appropriate colonoscopy surveillance period post-polypectomy.Current Concepts: The US Multi-Society Task Force, the European Society of Gastrointestinal Endoscopy, and the British Society of Gastroenterology revised their respective foreign guidelines in the 2020s. In Korea, a revised edition of post-polypectomy colonoscopic surveillance was announced in 2022, with the following risk factors: (1) adenoma ≥10 mm in size; (2) 3 to 5 (or more) adenomas; (3) tubulovillous or villous adenoma; (4) adenoma containing high-grade dysplasia; (5) traditional serrated adenoma; (6) sessile serrated lesions containing any grade of dysplasia; (7) serrated polyps of at least 10 mm in size; and (8) 3 to 5 (or more) sessile serrated lesions. In these guidelines, suitable surveillance periods are suggested for each risk factor.Discussion and Conclusion: The evidence supporting the best practices for post-polypectomy colonoscopy surveillance has strengthened, helping to support both close follow-up for some populations and less intense follow-up for others.

Compound traditional serrated adenoma and superficially serrated adenoma: a lesion of the rectum

Compound traditional serrated adenoma and superficially serrated adenoma: a lesion of the rectum

Endoscopic features with associated histological and molecular alterations in serrated polyps with dysplasia: Retrospective analysis of a tertiary case series

BackgroundSerrated polyps are incompletely understood lesions and include serrated sessile lesion (SSL) without or with dysplasia and traditional serrated adenoma (TSA). AimsWe investigated prevalence and characteristics of serrated lesions, especially SSL with dysplasia (mixed polyps). MethodsThis retrospective study analyzed data from consecutive patients referred for colonoscopy at a tertiary care center. Endoscopic and histopathological characteristics of identified lesions were studied. SSLs with dysplasia were molecularly analyzed for mutations and microsatellite instability. ResultsAmong 1147 patients, a total of 436 polyps were found, including 288 adenomas (66.1 %) and 114 serrated lesions (SLDR 26.2 %). PDR was 34.5 % and ADR was of 30.2 %. Serrated lesions included 75 hyperplastic polyps (17.2 %), 24 SSLs without dysplasia (5.5 %), 6 SSLs with dysplasia (mixed polyps) (1.4 %) and 9 TSA (2.1 %). The mixed polyps were evaluated molecularly: these analyses found no KRAS mutation, a single NRAS mutation in one lesion, the Val600Glu BRAF mutation in four lesions in both their serrated non-dysplastic and dysplastic areas, and microsatellite instability in four lesions, limited to the dysplastic areas. ConclusionOur single-center experience confirms the high prevalence of serrated lesions, a part of which are SSL with dysplasia. These lesions seem to carry specific molecular alterations.

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.

Morphological characteristics and diagnostic criteria of traditional serrated adenoma

Traditional serrated adenomas (TSAs) are extremely rare polyps from the group of serrated polyps of the colon. TSAs is no more than 5 % of all colon polyps. A relatively small number of studies have been devoted to this histological variant, at the same time, some aspects of the morphological diagnosis of TSA still remain undisclosed. Purpose: to conduct a clinical and morphological analysis of cases of TSAs.Materials and methods. The study included 57 cases of TSAs diagnosed in the period from 2021 to 2023. In the cases detected during this period, the results of histological and endoscopic studies were analyzed.Results. The age of patients ranged from 44 to 78 years and averaged 61.7 years. The ratio of men and women is 1:1.8. Most TSAs were found in the rectum (n = 28) and sigmoid colon (n = 20). In 8 cases, the tumor was localized in the descending part and the splenic flexure of the colon. In 1 observation, a tumor was found in the cecum. The sizes of the polyps ranged from 0.5 cm to 3.5 cm. In 22 cases, the composition of the polyp included tubulovillous adenomas (16 cases) and hyperplastic polyps (6 cases) in addition to TSAs. In 5 cases, foci of highly differentiated adenocarcinoma were detected in the TSAs material.Conclusion. TSAs has characteristic morphological features with a serrated exophytic growth pattern, cytoplasmic eosinophilia and the presence of ectopic crypts. Due to the difficulties of morphological diagnosis, TSAs in some cases remains undiagnosed. At the same time, due to the increased malignant potential, TSAs requires special vigilance on the part of pathologists and clinicians.

Clinical and endoscopic characteristics and management of 220 cases with serrated polyps

BackgroundSerrated polyps are considered the precursor lesions of colorectal cancer through the serrated pathway. In the present study, we aimed to evaluate and discuss the clinical and endoscopic characteristics and management of serrated polyps. MethodsThe data of 220 cases with serrated polyps between September 2018 and November 2021 in Shenzhen People's Hospital were retrospectively analyzed. ResultsOf all these cases, 32 were hyperplastic polyps, 36 were traditional serrated adenomas, 126 were sessile serrated lesions, 25 were SSLs with dysplasia, and one was an unclassified serrated adenoma. Although most patients were males aged ≥50 years and most serrated polyps were located in the distal colon and rectum with a size of 6–10 mm and the shape of type 0-Is, there was no significant difference (P > 0.05). Serrated polyps of ≤5 mm in size and type 0-IIa were mostly removed by cold biopsy forceps. Cold snare polypectomy was primarily used for those of 6–10 mm in size. Endoscopic mucosal resection was used for those of 6–20 mm, and endoscopic submucosal dissection was used for those of ≥20 mm (P < 0.05). All complications occurred in SSL patients with or without dysplasia (P < 0.05). ConclusionsClinical and endoscopic characteristics were beneficial for distinguishing and diagnosing serrated polyps. In addition, management options were crucial to prevent recurrence and progression. However, the detection rate of serrated polyps was relatively low. Therefore, prospective multicenter studies with large samples are necessary to better assess colorectal serrated polyps.

Impact of Clinical and Endoscopic Features on the Development of Metachronous Colorectal Advanced Serrated Lesions

High-risk adenomas predict metachronous advanced adenomatous neoplasia. Limited data exist on predictors of metachronous advanced serrated lesions (mASLs). We analyzed clinical and endoscopic predictors of mASLs. In this retrospective cohort study, adults with >1 outpatient colonoscopy between 2008 and 2019 at a tertiary center were included. Serrated lesions (SLs) included sessile SLs (SSLs), traditional serrated adenomas (TSAs), and hyperplastic polyps (HPs). Patient and endoscopic characteristics were obtained using electronic medical records. Five-year cumulative incidence of mASL (HP ≥10 mm, SSL ≥10 mm or with dysplasia, any TSA) and factors associated with mASL were evaluated using Kaplan-Meier estimates and Cox proportional hazards models. A total of 4990 patients were included and 45.4% were women. Mean age was 60.9 ± 9.2 years and median follow-up time was 3.7 years. Female sex and active smoking were associated with mASL. Endoscopically, any SSL and TSA were associated with mASL. The 5-year cumulative incidence for mASL was 26% (95% confidence interval [CI], 18%-32%) for SSL ≥10 mm, 17% (95% CI, 3.5%-29%) for HP ≥10 mm, 21% (95% CI, 0%-42%) for 3-4 SSLs <10 mm, 18% (95% CI, 0%-38%) for TSA, and 27% (95% CI, 3.6%-45%) for SSL with low-grade dysplasia. Baseline synchronous nonadvanced SL and nonadvanced adenoma were not associated with mASL. Our data support current recommendations for a 3-year surveillance interval in patients with baseline SSL ≥10 mm, SSL with dysplasia, and TSA. A 3-year interval may be more appropriate than 3-5 years for patients with baseline HP ≥10 mm or 3-4 SSLs <10 mm. Patients with synchronous nonadvanced SLs and adenomas do not appear to be at increased risk of mASL.