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INTRODUCTION: Risk factors for serrated polyps (SPs) are not well understood. METHODS: Multivariable analyses of data from a multicenter colonoscopy-based study estimated odds ratios for having either a sessile serrated lesion or traditional serrated adenoma according to participant characteristics. RESULTS: Six thousand seventy-eighty participants were included in the analyses (565 with either a sessile serrated lesion or traditional serrated adenoma). White race was associated with a higher risk of SPs compared with Black race (adjusted odds ratio 4.64, 95% confidence interval 1.89–11.41). Obesity and current smoking were also associated with a higher risk of SPs. DISCUSSION: White race, smoking, and obesity are risk factors for precancerous SPs. [ABSTRACT FROM AUTHOR]

Introduction: We investigated coexisting lesion types in patients with invasive colorectal cancer (CRC) in a multinational study for comprehending the adenoma-carcinoma and serrated pathway about the development of CRC. Methods: We retrospectively reviewed 3,050 patients enrolled in the international randomized controlled trial (ATLAS study) to evaluate the colorectal polyp detection performance of image-enhanced endoscopy in 11 institutions in four Asian countries/regions. In the current study, as a subgroup analysis of the ATLAS study, 92 CRC patients were extracted and compared to 2,958 patients without CRC to examine the effects of age, sex, and coexisting lesion types (high-grade adenoma [HGA], low-grade adenoma with villous component [LGAV], 10 adenomas, adenoma ≥10 mm, sessile serrated lesions [SSLs], and SSLs with dysplasia [SSLD]). Additional analyses of coexisting lesion types were performed according to sex and location of CRC (right- or left-sided). Results: A multivariate analysis showed that HGA (odds ratio [95% confidence interval] 4.29 [2.16–8.18]; p < 0.01), LGAV (3.02 [1.16–7.83], p = 0.02), and age (1.04 [1.01–1.06], p = 0.01) were independently associated with CRC. According to sex, the coexisting lesion types significantly associated with CRC were LGAV (5.58 [1.94–16.0], p < 0.01) and HGA (4.46 [1.95–10.20], p < 0.01) in males and HGA (4.82 [1.47–15.80], p < 0.01) in females. Regarding the location of CRC, SSLD (21.9 [1.31–365.0], p = 0.03) was significant for right-sided CRC, and HGA (5.22 [2.39–11.4], p < 0.01) and LGAV (3.46 [1.13–10.6], p = 0.02) were significant for left-sided CRC. Conclusions: The significant coexisting lesions in CRC differed according to sex and location. These findings may contribute to comprehending the pathogenesis of CRC. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Up to 30% of colorectal cancers (CRCs) develop from sessile serrated lesions (SSLs). Within the serrated neoplasia pathway, at least two principally distinct oncogenetic routes exist generating microsatellite‐stable and microsatellite‐instable CRCs, respectively. Aberrant DNA methylation (DNAm) is found early in the serrated pathway and might play a role in both oncogenetic routes. We studied a cohort of 23 SSLs with a small focus (<10 mm) of dysplasia or cancer, 10 of which were MLH1 deficient and 13 MLH1 proficient. By comparing, for each SSL, the methylation status of (1) the region of dysplasia or cancer (SSL‐D), (2) the nondysplastic SSL (SSL), and (3) adjacent normal mucosa, differentially methylated probes (DMPs) and regions (DMRs) were assessed both genome‐wide as well as in a tumor‐suppressor gene‐focused approach. By comparing DNAm of MLH1‐deficient SSL‐Ds with their corresponding SSLs, we identified five DMRs, including those annotating for PRDM2 and, not unexpectedly, MLH1. PRDM2 gene promotor methylation was associated with MLH1 expression status, as it was largely hypermethylated in MLH1‐deficient SSL‐Ds and hypomethylated in MLH1‐proficient SSL‐Ds. Significantly increased DNAm levels of PRDM2 and MLH1, in particular at 'critical' MLH1 probe sites, were to some extent already visible in SSLs as compared to normal mucosa (p = 0.02, p = 0.01, p < 0.0001, respectively). No DMRs, nor DMPs, were identified for SSLs destined to evolve into MLH1‐proficient SSL‐Ds. Our data indicate that, within both arms of the serrated CRC pathway, the majority of the epigenetic alterations are introduced early during SSL formation. Promoter hypermethylation of PRDM2 and MLH1 on the other hand specifically initiates in SSLs destined to transform into MLH1‐deficient CRCs suggesting that the fate of SSLs may not necessarily result from a stochastic process but possibly is already imprinted and predisposed. [ABSTRACT FROM AUTHOR]

Abstract Up to 30% of colorectal cancers (CRCs) develop from sessile serrated lesions (SSLs). Within the serrated neoplasia pathway, at least two principally distinct oncogenetic routes exist generating microsatellite‐stable and microsatellite‐instable CRCs, respectively. Aberrant DNA methylation (DNAm) is found early in the serrated pathway and might play a role in both oncogenetic routes. We studied a cohort of 23 SSLs with a small focus (

Background/Aims Some sessile serrated lesions (SSLs) progress into dysplasia and colorectal cancer, however, the clinical and endoscopic characteristics of SSLs with dysplasia remain to be determined. In this study, we elucidated these characteristics in SSLs with dysplasia/carcinoma, compared with those of SSLs without dysplasia. Methods We retrospectively collected the clinical, endoscopic, and pathological data of 254 SSLs from 216 patients endoscopically resected between January 2009 and December 2020. Results All SSLs included 179 without dysplasia and 75 with dysplasia/carcinoma, including 55 with low-grade dysplasia, 10 with high-grade dysplasia, and 10 with submucosal cancer. In clinical characteristics, SSLs with dysplasia/carcinoma were significantly associated with advanced age, metabolic diseases, and high-risk adenomas. In endoscopic characteristics, SSLs with dysplasia/carcinoma were significantly associated with the distal colon, large size, polypoid morphology, surface-changes, no mucus cap, and narrow-band imaging international colorectal endoscopic classification (NICE) type 2/3. In the multivariate analysis, high-risk adenomas (odds ratio [OR], 2.98; p = 0.01), large size (OR, 1.18; p < 0.01), depression (OR, 11.74; p = 0.03), and NICE type 2/3 (OR, 14.97; p < 0.01) were significantly associated with SSLs with dysplasia/carcinoma. Conclusions SSLs had a higher risk of dysplasia in the distal colon than in the proximal colon. SSLs with large size, depression, and adenomatous surface-patterns, as well as those in patients with high-risk adenomas, increased the risk of dysplasia/carcinoma. This suggests that the clinical and endoscopic characteristics can aid in the diagnosis and management of SSLs with dysplasia/carcinoma.

Objectives The histopathologic diagnosis of colorectal sessile serrated lesions (SSLs) and hyperplastic polyps (HPs) is of low consistency among pathologists. This study aimed to develop and validate a deep learning (DL)–based logical anthropomorphic pathology diagnostic system (LA-SSLD) for the differential diagnosis of colorectal SSL and HP. Methods The diagnosis framework of the LA-SSLD system was constructed according to the current guidelines and consisted of 4 DL models. Deep convolutional neural network (DCNN) 1 was the mucosal layer segmentation model, DCNN 2 was the muscularis mucosa segmentation model, DCNN 3 was the glandular lumen segmentation model, and DCNN 4 was the glandular lumen classification (aberrant or regular) model. A total of 175 HP and 127 SSL sections were collected from Renmin Hospital of Wuhan University during November 2016 to November 2022. The performance of the LA-SSLD system was compared to 11 pathologists with different qualifications through the human-machine contest. Results The Dice scores of DCNNs 1, 2, and 3 were 93.66%, 58.38%, and 74.04%, respectively. The accuracy of DCNN 4 was 92.72%. In the human-machine contest, the accuracy, sensitivity, and specificity of the LA-SSLD system were 85.71%, 86.36%, and 85.00%, respectively. In comparison with experts (pathologist D: accuracy 83.33%, sensitivity 90.91%, specificity 75.00%; pathologist E: accuracy 85.71%, sensitivity 90.91%, specificity 80.00%), LA-SSLD achieved expert-level accuracy and outperformed all the senior and junior pathologists. Conclusions This study proposed a logical anthropomorphic diagnostic system for the differential diagnosis of colorectal SSL and HP. The diagnostic performance of the system is comparable to that of experts and has the potential to become a powerful diagnostic tool for SSL in the future. It is worth mentioning that a logical anthropomorphic system can achieve expert-level accuracy with fewer samples, providing potential ideas for the development of other artificial intelligence models. [ABSTRACT FROM AUTHOR]

Background and Aim: Serrated polyps have been recognized as a premalignant lesion accounting for a significant proportion of colorectal cancer. Limited data are available regarding the risk factors for colorectal sessile serrated lesions (SSLs). We aimed to investigate clinical risk factors of SSLs and compared them with colorectal adenomas in a study population of Chinese individuals. Methods: A retrospective case–control study was performed in an academic tertiary‐referral center in Hong Kong. Subjects with SSLs and adenomas were identified from the hospital pathology database from January 2010 to December 2020, and additional clinical data were retrieved from the electronic patient record system. We compared clinical features and risk factors of SSL patients with those without these lesions. Results: A total of 2295 subjects were included in the study, including 459 subjects with SSLs, 918 subjects with adenomas, and 918 subjects with normal colonoscopy. By multivariable logistic regression, compared with normal subjects, patients with SSLs only were significantly more likely to have dyslipidemia (adjusted OR: 1.431, 95% CI 1.008–2.030) and diabetes mellitus (adjusted OR: 2.119, 95% CI 1.439–3.122). Conclusions: Dyslipidemia and diabetes were independent risk factors for SSLs. Our findings suggest these metabolic factors may be important for the risk of SSLs. The findings may improve our understanding of SSLs and shed light on patient selection for screening and risk stratification. [ABSTRACT FROM AUTHOR]

Introduction: Sessile serrated lesions (SSLs) have malignant potential for colorectal cancer in the serrated pathway. Selective endoscopic resection of SSLs would reduce medical costs and procedure-related accidents, but the accurate endoscopic differentiation of SSLs from hyperplastic polyps (HPs) is challenging. To explore the differential diagnostic performance of magnifying colonoscopy in distinguishing SSLs from HPs, we conducted a multicenter prospective validation study in clinical practice. Methods: Considering the rarity of diminutive SSLs, all lesions ≥6 mm that were detected during colonoscopy and diagnosed as type 1 based on the Japan narrow-band imaging expert team (JNET) classification were included in this study. Twenty expert endoscopists were asked to differentiate between SSLs and HPs with high or low confidence level after conventional and magnifying NBI observation. To examine the validity of selective endoscopic resection of SSLs using magnifying colonoscopy in clinical practice, we calculated the sensitivity of endoscopic diagnosis of SSLs with histopathological findings as comparable reference. Results: A total of 217 JNET type 1 lesions from 162 patients were analyzed, and 114 lesions were diagnosed with high confidence. The sensitivity of magnifying colonoscopy in detecting SSLs was 79.8% (95% confidence interval [CI]: 74.7–84.4%) overall, and 82.4% (95% CI: 76.1–87.7%) in the high-confidence group. These results showed that the sensitivity of this study was not high enough, even limited in the high-confidence group. Conclusions: Accurate differential diagnosis of SSLs and HPs using magnifying colonoscopy was challenging even for experts. JNET type 1 lesions ≥6 mm are recommended to be resected because selective endoscopic resection has a disadvantage of leaving approximately 20% of SSLs on site. [ABSTRACT FROM AUTHOR]

Background: Sessile serrated lesions (SSLs) are precursors of colon cancer, especially in cases of large, right colon. However, they are difficult to not only detect, but only clarify the margin of the lesion, which can lead to the poor endoscopic treatment outcomes. Aims: This study evaluated the usefulness of acetic acid spray with narrow-band imaging (A-NBI) for the better visualization of the margin of SSLs. Methods: From January 2013 to March 2022, patients with superficial elevated polyps suspected of being SSLs ≥ 10 mm with an endoscopic diagnosis that had been endoscopically resected at Hiroshima City Hiroshima Citizens Hospital were enrolled. Endoscopic images with white-light imaging (WLI), narrow-band imaging (NBI), indigo-carmine (IC), and A-NBI were recorded in each lesion and were randomly arranged and assessed by 10 endoscopists. We compared the visibility score (1 to 4) and color differences (ΔE) between inside and outside of the lesions among WLI, NBI, IC, and A-NBI. Results: Forty-one lesions in 33 cases were included, and a total of 164 images were evaluated. As for the visibility score, most of the lesions were scored as 1 or 2 on WLI, whereas most were scored 4 on A-NBI. The median ΔE of A-NBI was also significantly higher than that of WLI, NBI, or IC (20.5 vs. 8.3 vs. 8.2 vs. 12.3, P < 0.01). A significant correlation was observed between the color difference and visibility score (r = 0.53, P < 0.01). Conclusions: A-NBI may be a useful modality for identifying the margin of SSLs. [ABSTRACT FROM AUTHOR]

Sessile serrated lesions (SSLs) and microvesicular hyperplastic polyps (MVHPs) are colorectal lesions displaying gastric differentiation. Griffonia simplicifolia‐II (GS‐II) is a lectin specific to terminal α/βGlcNAc residues. Here, we assessed GS‐II binding and performed immunostaining for HIK1083 (specific to terminal αGlcNAc residues), MUC5AC, MUC6, and special AT‐rich sequence binding protein 2 (SATB2) in SSLs, MVHPs, and tubular adenomas (TAs). We observed MUC5AC positivity in 28 of 30 SSLs, but in only three of 23 TAs. Moreover, 24 of 30 SSLs were MUC6‐positive, while none of the 23 TAs were MUC6‐positive. None of the 30 SSLs or 23 TAs showed HIK1083 positivity. All 30 SSLs and 26 MVHPs were GS‐II‐positive, while only seven of 23 were in TAs. GS‐II staining was mainly distributed in the Golgi region, but SSLs and MVHPs showed goblet cell distribution, in 20 of 30 and 19 of 26 cases, respectively. All SSLs, MVHPs, and TAs were SATB2‐positive, but 21 of 30 SSLs and 12 of 26 MVHPs showed decreased staining intensity relative to adjacent mucosa, a decrease seen in only two of 23 in TAs. These results indicate overall that increased terminal βGlcNAc and decreased SATB2 expression are characteristics of SSLs and MVHPs. [ABSTRACT FROM AUTHOR]

Background: It is essential to accurately distinguish small benign hyperplastic colon polyps (HP) from sessile serrated lesions (SSL) or adenomatous polyps (TA) based on endoscopic appearances. Our objective was to determine the accuracy and inter-observer agreements for the endoscopic diagnosis of small polyps. Methods: High-quality endoscopic images of 30 small HPs, SSLs, and TAs were used randomly to create two-timed PowerPoint slide sets—one with and another one without information on polyp size and location. Seven endoscopists viewed the slides on two separate occasions 90 days apart, identified the polyp type, and graded their confidence level. Overall and polyp-specific accuracies were assessed for the group and individual endoscopists. Chi-square tests and Kappa (κ) statistics were used to compare differences as appropriate. Results: When polyp size and location were provided, overall accuracy was 67.1% for TAs, 50.0% for SSLs, and 41.4% for HPs; the corresponding accuracies were 60%, 44.3%, and 34.3% when polyp size and location were withheld (p <.001). Inter-observer agreement was moderate for TAs (κ = 0.50) and fair for SSLs (κ = 0.26) and HPs (κ = 0.29); the corresponding inter-observer agreements were 0.44, 0.31, and 0.17 with polyp size and location withheld. Accuracy was not affected by knowledge of polyp size, location, or confidence level. Endoscopists with ≥ 10 years (vs. < 10 years) of colonoscopy experience had marginally higher (56% vs. 40%, p = 0.05) accuracy for SSL diagnosis. Conclusions: The ability to distinguish between small TAs, SSLs, and HPs on their endoscopic appearance is poor regardless of the endoscopists' knowledge of polyp size and location. [ABSTRACT FROM AUTHOR]

Background and Aim: Sessile serrated lesions (SSLs) act as precursors to colorectal cancer, sometimes harbor carcinomas, and are sometimes incompletely resected. We aimed to evaluate local recurrence after endoscopic resection of SSL ≥10 mm. Methods: This prospective, single‐arm, observational study was performed at eight Japanese tertiary institutions. Colorectal lesions ≥10 mm were resected endoscopically, and the pathological diagnosis was either an SSL or hyperplastic polyp (HP). Follow‐up colonoscopy was performed 1 year later, and the local recurrence was evaluated by biopsy. Results: From October 2018 to September 2021, 104 cases with 123 lesions were registered. Among the pathologically diagnosed 105 SSLs and 18 HPs, 95 and 7 lesions were diagnosed as SSLs and HPs, respectively, by central pathological review. Among the 104 endoscopically diagnosed SSLs, 86 were diagnosed as SSLs, whereas among the 11 endoscopically diagnosed HPs, two were diagnosed as HPs by central pathological review (the rest were SSLs). Among the 95 patients with 113 lesions who underwent follow‐up colonoscopy, resection scars were identified in 95 (84%) lesions. Three (3.1%; 95% confidence interval 0.6–8.7%) local recurrences were diagnosed pathologically among 98 pathologically diagnosed SSLs. Two (6%) local recurrences were diagnosed in patients with SSLs ≥20 mm. Conclusions: The local recurrence rate after endoscopic resection of SSLs ≥10 mm was 3.1%. Careful follow‐up is recommended after endoscopic resection of large SSLs. Endoscopically diagnosed HPs ≥10 mm were sometimes pathologically diagnosed as SSL and should be considered for resection. [ABSTRACT FROM AUTHOR]

Background/aims: Growing recognition identifies sessile serrated lesions (SSL) as colorectal cancer (CRC) precursors. However, the SSL detection rate remains debatable and lacks a definitive consensus. Additionally, understanding the influencing factors in SSL development is limited. We aim to retrospectively analyze the true prevalence and risk factors of SSL in China., Materials and Methods: This retrospective study collected medical data from patients who underwent colonoscopy at the Endoscopy Center of Shanghai East Hospital affiliated with Tongji University between March 1, 2019 and February 28, 2022. Data were sourced through the electronic medical record system and included information such as age, sex, lesion location, number, and pathology. This study predominantly focused on the detection rate and the clinical and endoscopic features of SSL., Results: Of 72 287 colonoscopies in 3 years, 3905 cases were histologically confirmed as SSL. Among them, 2290 (58.6%) were male, and 1615 (41.4%) were female. The overall SSL detection rate was 5.40%, slightly surpassing Asian/Chinese averages but lower than Western rates. Males had a higher SSL detection rate (6.1%) than females (4.6%). Univariate analysis revealed a significant association between SSL with dysplasia/adenocarcinoma (SSL-D/AD) and obesity (Body Mass Index, BMI ≥ 24), CRC family history, and hypertension. After multivariable logistic regression, only obesity (BMI ≥ 24) remained a statistically significant independent risk factor for SSL-D/AD., Conclusions: The SSL detection rate at our center is 5.4% and increases with age. Males have a significantly higher detection rate than females. Our findings suggest that endoscopists should consider risk factors for SSL-D/AD, such as obesity, CRC family history, and hypertension.

Over the last decade, our knowledge of colorectal serrated polyps and lesions has significantly improved due to numerous studies on this group of precursor lesions. Serrated lesions were misleading as benign before 2010, but they are currently reclassified as precancerous lesions that contribute to 30% of colorectal cancer through the serrated neoplasia pathway. The World Health Organization updated the classification for serrated lesions and polyps of the colon and rectum in 2019, which is more concise and applicable in daily practice. The responsible authors prescribe that "colorectal serrated lesions and polyps are characterized by a serrated (sawtooth or stellate) architecture of the epithelium." From a clinical standpoint, sessile serrated lesion (SSL) and SSL with dysplasia (SSLD) are the two most significant entities. Despite these advancements, the precise diagnosis of SSL and SSLD based mainly on histopathology remains challenging due to various difficulties. This review describes the nomenclature and the terminology of colorectal serrated polyps and lesions and highlights the diagnostic criteria and obstacles encountered in the histopathological diagnosis of SSL and SSLD., Competing Interests: Conflict-of-interest statement: The authors have disclosed that they have no significant relationships with or financial interest in any commercial companies mentioned in this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background and Aim: The reported prevalence and risk factors for sessile serrated lesions (SSLs) show significant variation. We aimed to specifically study the prevalence and potential risk factors of SSLs in an average risk colorectal cancer (CRC) screening population of Chinese subjects. Methods: This is a case–control study of prospectively collected data from a territory‐wide colorectal screening program in Hong Kong. Information on risk factors was obtained from questionnaires completed prior to screening colonoscopy. We compared subjects with SSLs against controls without these lesions to identify potential risk factors using multivariable logistic regression. Results: Of 12 039 asymptomatic screening subjects, 6011 subjects received a screening colonoscopy with 2214 subjects (36.8%) having conventional adenomas, 486 subjects (8.1%) having hyperplastic polyps, and 85 subjects (1.4%) having SSLs only. Of these subjects, three had synchronous advanced adenomas and were excluded from the analysis. More than 60% of these lesions were in the proximal colon. We compared these 82 subjects with SSLs only and 3226 controls without any polyps. After multivariable logistic regression, age ≥ 66 years, smoking, and diabetes mellitus (DM) were significant independent risk factors for SSLs. Conclusion: In this study, we report the prevalence of SSLs to be 1.4%. Age ≥ 66 years, smoking, and DM were independent risk factors for these lesions. Our findings provide relevant new data that should be taken into consideration when designing region‐specific surveillance programs for SSLs with the ultimate goal of reducing the risk of CRC. [ABSTRACT FROM AUTHOR]

Since the 19905, the incidence of Sessile Serrated Adenomas (SSA) and Colorectal Cancer (CRC) in people vounger than 50 years old has dramatically increased; why is this? Anecdotally, a simple linear connection between 5SA and CRC rcould be present, given thai serrated neoplasia accounts for about one-third of all colorectal cancers (Nalankilli et al., 2019). However, serrated adenomas generally affect the proximal colon while colorectal cancers in theyoung, predominantly reside in the distal colon and rectum. Speculation could point to unhealthy changes in diet, sedentary and other lifestyle factors: or perhaps rprent reclassification of our understandingof SSA and the CRC pathways resulting in increased diagnoses; or even changes to ourscreening and surveillance practices, This paper aims to provide an overview of SSA and CRC in individuals younger than 50 years, contributing diet and lifestyle factors, hurdles in diagnosis and prevention, and how they potentially contribute to these growing incidences. [ABSTRACT FROM AUTHOR]

Introduction. Polypectomy has been shown to reduce the incidence of colorectal cancer. The ESGE guidelines from 2017 recommends that cold snare polypectomy should be used for removal of the diminutive polyps, smaller than 5 mm and also for sessile polyps 6 - 9 mm in size. This recommendation is based on lower complication rates and higher complete resections. Objectives. The goal of the study is to establish if the cold snare polypectomy is safe in removing the polyps smaller than 1 cm. Methods. The patients with polyps detected at colonoscopy between 2020-2022 years in the Gastroenterology Clinic from the Emergency Hospital, Targu-Mures entered this study. Results. From the total number of the polyps (753), 623 (82,73%) were adenoma and 130 (17,26%) were sessile. From the last group 83 were hyperplastic polyps, 35 sessile serrated lesions (SSL) and 12 traditional serrated adenomas (TSA). The hyperplastic polyps and 75% of the SSA were resected with cold snare, being less than 1cm. There were no bleedings and no complications. The rest of the SSL were resected by hot snare, with no complications either. Conclusions. Cold snare polypectomy is safe in serrated lesions less than 1 cm. There are recently published studies that demonstrated that cold snare polypectomy is safe also in SSA larger than 1 cm, however this has to be further established in the future guidelines. [ABSTRACT FROM AUTHOR]

Background: Sessile serrated lesions (SSLs) are often missed on colonoscopy, and studies have shown this to be an essential cause of interstitial colorectal cancer. The SSLs with dysplasia (SSL-D + ), in particular, have a faster rate of carcinogenesis than conventional tubular adenomas. Therefore, there is a clinical need for some endoscopic features with independent diagnostic value for SSL-D + s to assist endoscopists in making immediate diagnoses, thus improving the quality of endoscopic examination and treatment., Aim: To compare the characteristics of SSLs, including those with and without dysplasia (SSL-D + and SSL-D - ), based on white light and image-enhanced endoscopy, to achieve an immediate differential diagnosis for endoscopists., Methods: From January 2017 to February 2023, cases of colorectal SSLs confirmed by colonoscopy and histopathology at the Gastrointestinal Endoscopy Center of Beijing Tsinghua Changgung Hospital were collected. The general, endoscopic, and histopathological data were reviewed and analyzed to determine the diagnostic utility. Univariate analysis was used to find potential diagnostic factors, and then multivariate regression analysis was performed to derive endoscopic features with independent diagnostic values for the SSL-D + ., Results: A total of 228 patients with 253 lesions were collected as a result. There were 225 cases of colorectal SSL-D - s and 28 cases of SSL-D + s. Compared to the colorectal SSL-D - , the SSL-D + was more common in the right colon ( P = 0.027) with complex patterns of depression, nodule, and elevation based on cloud-like surfaces ( P = 0.003), reddish ( P < 0.001), microvascular varicose ( P < 0.001), and mixed type (Pit II, II-O, IIIL, IV) of crypt opening based on Pit II-O ( P < 0.001). Multifactorial logistic regression analysis indicated that lesions had a reddish color [odds ratio (OR) = 18.705, 95% confidence interval (CI): 3.684-94.974], microvascular varicose (OR = 6.768, 95%CI: 1.717-26.677), and mixed pattern of crypt opening (OR = 20.704, 95%CI: 2.955-145.086) as the independent predictors for SSL-D + s., Conclusion: The endoscopic feature that has independent diagnostic value for SSL-D + is a reddish color, microvascular varicose, and mixed pattern of crypt openings., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Transfer RNA (tRNA)-derived small RNAs (tsRNAs) are small fragments that form when tRNAs severe. tRNA halves (tiRNAs), a subcategory of tsRNA, are involved in the oncogenic processes of many tumors. However, their specific role in sessile serrated lesions (SSLs), a precancerous lesion often observed in the colon, has not yet been elucidated., Aim: To identify SSL-related tiRNAs and their potential role in the development of SSLs and serrated pathway of colorectal cancer (CRC)., Methods: Small-RNA sequencing was conducted in paired SSLs and their adjacent normal control (NC) tissues. The expression levels of five SSL-related tiRNAs were validated by q-polymerase chain reaction. Cell counting kit-8 and wound healing assays were performed to detect cell proliferation and migration. The target genes and sites of tiRNA-1:33-Pro-TGG-1 (5'tiRNA-Pro-TGG) were predicted by TargetScan and miRanda algorithms. Metabolism-associated and immune-related pathways were analyzed by single-sample gene set enrichment analysis. Functional analyses were performed to establish the roles of 5'tiRNA-Pro-TGG based on the target genes., Results: In total, we found 52 upregulated tsRNAs and 28 downregulated tsRNAs in SSLs compared to NC. The expression levels of tiRNA-1:33-Gly-CCC-2, tiRNA-1:33-Pro-TGG-1, and tiRNA-1:34-Thr-TGT-4-M2 5'tiRNAs were higher in SSLs than those in NC, while that of 5'tiRNA-Pro-TGG was associated with the size of SSLs. It was demonstrated that 5'tiRNA-Pro-TGG promoted cell proliferation and migration of RKO cell in vitro . Then, heparanase 2 ( HPSE2 ) was identified as a potential target gene of 5'tiRNA-Pro-TGG. Its lower expression was associated with a worse prognosis in CRC. Further, lower expression of HPSE2 was observed in SSLs compared to normal controls or conventional adenomas and in BRAF -mutant CRC compared to BRAF -wild CRC. Bioinformatics analyses revealed that its low expression was associated with a low interferon γ response and also with many metabolic pathways such as riboflavin, retinol, and cytochrome p450 drug metabolism pathways., Conclusion: tiRNAs may profoundly impact the development of SSLs. 5'tiRNA-Pro-TGG potentially promotes the progression of serrated pathway CRC through metabolic and immune pathways by interacting with HPSE2 and regulating its expression in SSLs and BRAF -mutant CRC. In the future, it may be possible to use tiRNAs as novel biomarkers for early diagnosis of SSLs and as potential therapeutic targets in serrated pathway of CRC., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

Along with the discovery and refinement of serrated pathways, the World Health Organization amended the classification of digestive system tumors in 2019, recommending the renaming of sessile serrated adenomas/polyps to sessile serrated lesions (SSLs). Given the particularity of the endoscopic appearance of SSLs, it could easily be overlooked and missed in colonoscopy screening, which is crucial for the occurrence of interval colorectal cancer. Existing literature has found that adequate bowel preparation, reasonable withdrawal time, and awareness of colorectal SSLs have improved the quality and accuracy of detection. More particularly, with the continuous advancement and development of endoscopy technology, equipment, and accessories, a potent auxiliary tool is provided for accurate observation and immediate diagnosis of SSLs. High-definition white light endoscopy, chromoendoscopy, and magnifying endoscopy have distinct roles in the detection of colorectal SSLs and are valuable in identifying the size, shape, character, risk degree, and potential malignant tendency. This article delves into the relevant factors influencing the detection rate of colorectal SSLs, reviews its characteristics under various endoscopic techniques, and expects to attract the attention of colonoscopists., Competing Interests: Conflict-of-interest statement: All authors declare that there is no conflict-of-interest., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Although the risk of colorectal cancer increases with advancing age, there remains a lack of guidelines for surveillance colonoscopy in the octogenarian and older population. Our objective is to document the diagnostic yield of surveillance colonoscopies, and to analyze adenoma characteristics, complications, and short-term survival in asymptomatic octogenarian and older patients undergoing adenoma surveillance colonoscopy., Methods: Surveillance colonoscopies performed at a tertiary level hospital colorectal surgery department between January 2010 and September 2018 were queried from a prospectively maintained institutional colonoscopy database. Patients 80 years old or older undergoing routine surveillance colonoscopy after having had an adenoma or advanced adenoma diagnosed on a prior exam were included in the study., Results: 604 patients were included in the study with a median age of 82 and 43% were female. Median follow-up was 52 months (range 2-110), with 511(85%) patients alive at their last available follow-up. Overall, 292 patients had at least one had adenomatous lesion and 105 (17.4%) patients had advanced adenomas. Increasing age was not associated with increased rate of sessile serrated lesions (p = 0.2) however, there was an association between increasing age and advanced adenoma rates (p = 0.01). Advanced adenomas were more commonly found to be right-sided (p = 0.02). Four asymptomatic patients were diagnosed with cancer at surveillance (0.6%)., Conclusions: Patients 80 years of age or older with a previous history of colorectal adenoma(s) may have a high risk of future advanced lesions and can be considered to undergo surveillance colonoscopy., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Serrated polyp associated colorectal cancer (CRC) develops from an alternative mechanism of colorectal carcinogenesis and accounts for 10-15% of all CRC. Serrated polyposis syndrome (SPS) occurs infrequently and is characterized by the occurrence of multiple serrated polyps (hyperplastic polyps, sessile serrated lesions and traditional serrated adenomas) throughout the colon and/or rectum and has been strongly associated with development of CRC. However, SPS is frequently unrecognized, due to application failure of the WHO criteria regarding diagnosis and/or missed serrated polyps during endoscopy. The management of SPS requires surveillance at regular intervals and removal of large serrated polyps. Endoscopic resection suitability and technique depends on lesion size and the endoscopist's experience. In this manuscript, we present an update regarding SPS epidemiology, molecular characteristics, management, surveillance strategies and endoscopic resection techniques., Competing Interests: None., (AJTR Copyright © 2021.)

Background and Aim: Cold snare polypectomy (CSP) is growing in popularity due to its safety and convenience. Its indication is benign tumours such as adenoma and sessile serrated lesions (SSLs) <10 mm in size. CSP for SSLs ≥10 mm in size has not been well examined. In this study, we aimed the feasibility of this treatment regarding therapeutic results and local recurrence., Methods: This was a single-centre retrospective cohort study. We reviewed SSLs with or without dysplasia of 10-20 mm that were resected by CSP from 2014 to 2020. All tumours were diagnosed endoscopically as SSLs without dysplasia before CSP with the help of magnifying narrow band imaging or blue laser imaging. We analysed the lesion characteristics, en bloc resection, histopathological diagnosis, adverse events and local recurrence. We analysed risk factors for recurrence, comparing recurrent lesions to non-recurrent lesions. We also compared risk factors for lesions 10-14 mm in size to those for lesions 15-20 mm in size., Results: We analysed 160 lesions in 100 patients (M age  ± SD = 67.7 ± 10.1 years). The polyp size (M ± SD) was 11.8 ± 2.8 mm, and the en bloc resection rate was 60.0% (96 cases). The rates of massive perioperative haemorrhage, postoperative haemorrhage and perforation were 1.3%, 0% and 0%, respectively. Regarding histopathological diagnosis, two (1.2%) cases showed SSLs with high-grade dysplasia. The recurrence rate in 101 lesions with a median follow-up period of 18 months (interquartile range 12-24 months) was 5.0%. There were no significant risk factors such as tumour size, location, morphology and so on in terms of recurrence. All recurrent cases could be resected by repeat CSP. The recurrence rates of lesions 10-14 mm in size and 15-20 mm in size were 4.7% and 6.3%, respectively (p = 0.713)., Conclusion: CSP of SSLs ≥10 mm in size according to magnifying endoscopic diagnosis was safe and promising, but the rate of recurrence was slightly high, meaning that close follow-up is required., (© 2020 The Authors. United European Gastroenterology Journal published by Wiley Periodicals LLC. on behalf of United European Gastroenterology.)

In the last two decades, the vision of a unique carcinogenesis model for colorectal carcinoma (CRC) has completely changed. In addition to the adenoma to carcinoma transition, colorectal carcinogenesis can also occur via the serrated pathway. Small non-coding RNA, known as microRNAs (miRNAs), were also shown to be involved in progression towards malignancy. Furthermore, increased expression of certain miRNAs in premalignant sessile serrated lesions (SSLs) was found, emphasizing their role in the serrated pathway progression towards colon cancer. Since miRNAs function as post-transcriptional gene regulators, they have enormous potential to be used as useful biomarkers for CRC and screening in patients with SSLs particularly. In this review, we have summarized the most relevant information about the specific role of miRNAs and their relevant signaling pathways among different serrated lesions and polyps as well as in serrated adenocarcinoma. Additional focus is put on the correlation between gut immunity and miRNA expression in the serrated pathway, which remains unstudied., Competing Interests: Conflict-of-interest statement: Authors declare no conflict of interests for this article., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: A low adenoma detection rate (ADR) increases risks of interval cancers (ICs). Proximal colon flat polyps, e.g. serrated lesions (SLs), are difficult to find. Missed proximal colon flat lesions likely contribute to IC., Aims: We compared chromoendoscopy with water exchange (CWE), water exchange (WE) and air insufflation (AI) in detecting adenomas in screening colonoscopy., Methods: After split-dose preparation, 480 veterans were randomized to AI, WE and CWE., Results: Primary outcome of proximal ADR (55.6% vs 53.4% vs 52.2%, respectively) were similar in all groups. Adenoma per colonoscopy (APC) and adenoma per positive colonoscopy (APPC) were comparable. Detection rate of proximal colon SLs was significantly higher for CWE and WE than AI (26.3%, 23.6% and 11.3%, respectively, p  = 0.002). Limitations: single operator; SLs only surrogate markers of but not IC., Conclusions: When an endoscopist achieves high-quality AI examinations with overall ADR twice (61.6%) the recommended standard (30%), use of WE and CWE does not produce further improvement in proximal or overall ADR. Comparable APC and APPC confirm equivalent withdrawal inspection techniques. WE alone is sufficient to significantly improve detection of proximal SLs. The impact of increased detection of proximal SLs by WE on prevention of IC deserves to be studied. This study is registered at ClinicalTrial.gov (NCT#01607255).