Morphological characteristics, classifications and difficulties in the use of diagnostic criteria for serrated lesions of the large intestine

Abstract: Introduction Colorectal carcinoma (CRC) is the most common gastrointestinal neoplasm in the world, accounting for 15% of cancer-related deaths. This condition is related to different molecular pathways, among them the recently described serrated pathway, whose characteristic entities, serrated lesions, have undergone important changes in their names and diagnostic criteria in the past thirty years. The multiplicity of denominations and criteria over the last years may be responsible for the low interobserver concordance (IOC) described in the literature. Objectives: The present study aims to describe the evolution in classification of serrated lesions, based on the last three publications of theWorld Health Organization (WHO) and the reproducibility of these criteria by pathologists, based on the evaluation of the IOC. Methods: A search was conducted in the PubMed, ResearchGate and Portal Capes databases, with the following terms: sessile serrated lesion; serrated lesions; serrated adenoma; interobserver concordance; andreproducibility.Articlespublished since 1990were researched. Results and Discussion: The classification of serrated lesions in the past thirty years showed different denominations and diagnostic criteria. The reproducibility and IOC of these criteria in the literature, based on the kappa coefficient, varied in most studies, from very poor to moderate. Conclusions: Interobserver concordance and the reproducibility of microscopic criteria may represent a limitation for the diagnosis andappropriatemanagementof these lesions. It is necessary to investigate diagnostic tools to improve the performance of the pathologist's evaluation, for better concordance, and, consequently, adequate diagnosis and treatment. (AU)

Clinicopathological features of the colorectal serrated adenoma and analysis on influencing factors of malignancy / 中华胃肠外科杂志

Objective: Serrated adenoma is recognized as a precancerous lesion of colorectal cancer, and the serrated pathway is considered as an important pathway that can independently develop into colorectal cancer. However, little is known about the related risk factors of carcinogenesis of serrated adenoma. The purpose of this study was to analyze the distribution characteristics and potential malignant factors of serrated adenoma in the colon and rectum. Methods: A retrospective case-control study was conducted to collect the clinical data of patients with serrated adenoma who underwent colonoscopy and were pathologically diagnosed in the Cancer Hospital of Chinese Academy of Medical Sciences from April 2017 to July 2019, and exclude patients with two or more pathological types of lesions. The clinical characteristics of serrated adenoma were summarized, and univariate and logistic multivariate regression analysis was conducted to explore the influencing factors for serrated adenoma to develop malignant transformation. Results: Among 28 730 patients undergoing colonoscopy, 311 (1.08%) were found with 372 serrated adenomas, among which 22 (5.9%) were sessile serrated adenomas/polyps, 84 (22.6%) were traditional serrated adenomas, and 266 (71.5%) were unclassified serrated adenomas according to WHO classification. The pathological results showed that 106 (28.5%) lesions were non-dysplasia, 228 (61.3%) lesions were low grade intraepithelial neoplasia, and 38 (10.2%) lesions were high grade intraepithelial neoplasia or cancer. There were 204 (54.8%) lesions with long-axis diameter <10 mm and 168 (45.2%) lesions with length long-axis ≥ 10 mm. 238 (64.0%) lesions were found in the left side colon and rectum and 134 (36.0%) lesions in the right side colon. Gross classification under endoscopy: 16 flat type lesions (4.3%), 174 sessile lesions (46.8%), 117 semi-pedunculated lesions (31.5%), 59 pedunculated lesions (15.9%). Narrow-band imaging international colorectal endoscopic (NICE) classification: 85 (22.8%) type I lesions, 280 (75.3%) type II lesions, 4 (1.1%) type III lesions. Univariate analysis showed that lesion size, lesion location, lesion site and different WHO classifications were associated with malignant transformation of colorectal serrated adenoma (all P<0.05). For the serrated adenomas with different NICE classifications, there were statistically significant differences in the distribution of malignant lesions among groups (P=0.001). Multivariate analysis showed that the long-axis diameter of the lesion ≥10 mm (OR=6.699, 95% CI: 2.843-15.786) and the lesion locating in the left side colorectum (OR=2.657, 95% CI: 1.042-6.775) were independent risk factors for malignant transformation. Conclusions: Serrated adenomas mainly locate in the left side colon and rectum, and are prone to malignant transformation when the lesions are ≥10 mm in long-axis diameter or left-sided.

Location and Size are Useful Features in Diagnosing Sessile Serrated Adenoma/Polyp

@#Introduction: According to the predefined 2010 World Health Organisation criteria, serrated colonic polyps (SCP) are pathologically classified into hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P) with or without cytological dysplasia and traditional serrated adenoma (TSA). Sessile serrated adenoma/polyp is acknowledged as a precursor of colorectal carcinoma through the serrated neoplastic pathway. Hyperplastic polyps display similar histological features to SSA/P, in comparison to other types of SCP. It is noteworthy to discriminate between HP and SSA/P, since only the latter has a malignant potential. Method: A total of 198 cases of SCP were identified and the slides were reexamined and reclassified accordingly. Analysis on the proportion of SSA/P among SCP and underdiagnosed cases of SSA/P was performed. The association between SSA/P and non-SSA/P with demographic data and colonoscopic findings were also studied. Results: From the 198 cases of SCP, 164, 29 and five cases were reclassified as HP, SSA/P and TSA respectively. Sixteen cases of SSA/P were underdiagnosed as HP. From among 29 cases of SSA/P, the majority were ≥ 65 years old (17; 58.6%), male (21; 72.4 %) and Chinese (17; 58.6%). Most of the SSA/P (16; 55.2 %) were located in the right colon and measured ≥ 10mm (9; 31%) in size. Location (p=0.004) and size (p=0.013) of the colonoscopic findings were significantly associated with SSA/P. Conclusion: Underdiagnosed cases of SSA/P among HP were identified most likely because of the resemblance of their histological features. The location and size of SCP may suggest the probability of SSA/P.

Clinical outcomes of surveillance colonoscopy for patients with sessile serrated adenoma

BACKGROUND/AIMS: Sessile serrated adenomas (SSAs) are known to be precursors of colorectal cancer (CRC). The proper interval of follow-up colonoscopy for SSAs is still being debated. We sought to determine the proper interval of colonoscopy surveillance in patients diagnosed with SSAs in South Korea. METHODS: We retrospectively reviewed the medical records of patients diagnosed with SSAs who received 1 or more follow-up colonoscopies. The information reviewed included patient baseline characteristics, SSA characteristics, and colonoscopy information. RESULTS: From January 2007 to December 2011, 152 SSAs and 8 synchronous adenocarcinomas were identified in 138 patients. The mean age of the patients was 62.2 years and 60.1% patients were men. SSAs were located in the right colon (i.e., from the cecum to the hepatic flexure) in 68.4% patients. At the first follow-up, 27 SSAs were identified in 138 patients (right colon, 66.7%). At the second follow-up, 6 SSAs were identified in 65 patients (right colon, 66.7%). At the 3rd and 4th follow-up, 21 and 11 patients underwent colonoscopy, respectively, and no SSAs were detected. The total mean follow-up duration was 33.9 months. The mean size of SSAs was 8.1±5.0 mm. SSAs were most commonly found in the right colon (126/185, 68.1%). During annual follow-up colonoscopy surveillance, no cancer was detected. CONCLUSIONS: Annual colonoscopy surveillance is not necessary for identifying new CRCs in all patients diagnosed with SSAs. In addition, the right colon should be examined more carefully because SSAs occur more frequently in the right colon during initial and follow-up colonoscopies.

Endoscopic Features of Mucous Cap Polyps: A Way to Predict Serrated Polyps

BACKGROUND/AIMS: The aims of the study were to identify whether a mucous-cap predicts the presence of serrated polyps, and to determine whether additional endoscopic findings predict the presence of a sessile serrated adenomas/polyp (SSA/P). METHODS: We analyzed 147 mucous-capped polyps with corresponding histology, during 2011–2014. Eight endoscopic features (presence of borders, elevation, rim of debris, location in the colon, size ≥10 mm, varicose vessels, nodularity, and alteration in mucosal folds) of mucous-capped polyps were examined to see if they can predict SSA/Ps. RESULTS: A total of 86% (n=126) of mucous-capped polyps were from the right sided serrated pathway (right-sided hyperplastic [n=83], SSA/Ps [n=43], traditional serrated adenoma [n=1]), 10% (n=15) were left-sided hyperplastic polyps, and 3% (n=5) were from the adenoma-carcinoma sequence. The presence of a mucous cap combined with varicose vessels was the only significant predictor for SSA/Ps. The other seven characteristics were not found to be statistically significant for SSA/Ps, although location in the colon and the presence of nodularity trended towards significance. CONCLUSIONS: Our study suggests that mucous-capped polyps have high predictability for being a part of the serrated pathway. Gastroenterologists should be alert for a mucous-capped polyp with varicose veins, as these lesions have a higher risk of SSA/P.

Endoscopic and pathological features of advanced colorectal serrated adenoma / 中华消化内镜杂志

Objective To analyze the clinical and pathological features of advanced colorectal serrated adenoma(ACSA). Methods The endoscopic and pathological features of 156 cases of ACSA and 121 cases of non-ACSA diagnosed in General Hospital, Tianjin Medical University from January 2010 to March 2016 were retrospectively analyzed and compared.Results ACSA and non-ACSA cases accounted for 56.3%(156/277)and 43.7%(121/277)of all patients with colorectal serrated lesions,respectively. The mean age of ACSA patients was 57.79±13.65 years and 89(57.1%)of these patients were male. There was no significant difference in age and gender between ACSA and non-ACSA patients. A total of 161 ACSA lesions were diagnosed,including 71 sessile serrated adenoma/polyps and 90 traditional serrated adenomas. Among the 161 ACSA lesions,there were 29(18.0%)lesions whose diameter≥10 mm, and 84(52.2%) lesions located in the proximal colon, which were more than non-ACSA(84/161 VS 49/134,P=0.007). ACSA was classified under endoscopy into pedunculated type(20/161),sub-pedunculated type(35/161), sessile type(24/161),flat type(79/161)and laterally spreading tumor(3/161), and the distribution of lesion type was significantly different from non-ACSA(P<0.001). One hundred and sixty(99.4%)ACSA lesions were diagnosed as dysplasia, including 158 low degree dysplasia and 2 high degree dysplasia.Moreover,16 ACSA patients were accompanied with synchronous advanced colorectal neoplasia(sACN), and large serrated polyps(diameter≥10 mm)might have a strong association with sACN(OR=4.35, 95%CI:1.467-12.894, P<0.05). Conclusion ACSA is more common in proximal colon and sub-pedunculated type,sessile type and flat type. ACSA diameter≥10 mm is significantly associated with sACN.

Diagnostic value of white light endoscopy and narrow band imaging for colorectal sessile serrated adenoma and hyperplastic polyp / 中华消化内镜杂志

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.

Morphological features of colorectal sessile serrated adenoma/polyp under white light endoscopy and narrow band imaging / 中国内镜杂志

Objective To investigate the morphological features of colorectal sessile serrated adenoma/polyp (SSA/P) by white light endoscopy (WLE) and narrow band imaging (NBI). Methods A retrospective analysis was made on the morphological characteristics of SSA/P from January 2014 to March 2017, and compared with HP. Results There were 50 cases of SSA/P from 41 patients and 50 cases of HP from 43 patients. SSA/P located in the right colon was more than HP, but the difference was no statistical significance (16 cases vs 14 cases,P > 0.05). SSA/P have 11 cases of Type Is, 21 cases of Type IIa, 16 cases of Type IIb, 2 cases of Type LST, HP have 17 cases of Type Is, 25 cases of Type IIa, 8 cases of Type IIb, there was no significant difference (P > 0.05); SSA/P has more mucus than HP (37 cases vs 11 cases, P < 0.05). In NBI: The proportion of SSA/P with a red mucus cap, indistinctive borders, irregular shape, black dots inside the crypts, Cloud-like surface, Type II-O pit pattern and varicose microvascular vessels were higher than that of HP (P < 0.05). In the differential prediction of SSA/P and HP: Black dots inside the crypts (OR

Comparisons of Gut Microbiota Among Healthy Control, Patients With Conventional Adenoma, Sessile Serrated Adenoma, and Colorectal Cancer

BACKGROUND: Studies on gut microbiota regarding colorectal carcinogenesis, including sessile serrated adenoma (SSA), have been scarce. The aim of this study is to investigate the role of mucosa-associated gut microbiota in the colorectal carcinogenesis. METHODS: We collected biopsy samples of normal rectal mucosa during colonoscopy from healthy control and patients with conventional adenoma, SSA, and colorectal cancer (CRC), respectively (n = 6). Pyrosequencing for 16S rRNA gene of bacteria was performed to compare gut microbiota. RESULTS: The most abundant phylum in total samples was Proteobacteria (55.6%), followed by Firmicutes (27.4%) and Bacteroidetes (11.6%). There was no significant difference in relative abundance of the phylum level among the four groups. Fusobacterium nucleatum, known to be frequently detected during colorectal carcinogenesis, was found in only one sample of patient with SSA. The rarefaction curves showed that the diversity of mucosal communities of patients with CRC is the lowest among the four groups and the diversity of mucosal communities of patients with SSA is higher than that of healthy control. Among the four groups, Shannon's and Simpson's index for diversity was the lowest and the highest in the patients with CRC, respectively; it did not reach statistical significance. The proportion of genus Pseudomonas was very high in the samples of patients with stage II–IV CRC compared with those with stage I CRC (59.3% vs. 0.3%, P = 0.064). CONCLUSIONS: Our study suggests no significant role of mucosa-associated gut microbiota in the colorectal carcinogenesis. Further study for many samples or using fecal material could be helpful.

Sessile Serrated Adenomas: How to Detect, Characterize and Resect

Serrated polyps are important contributors to the burden of colorectal cancers (CRC). These lesions were once considered to have no malignant potential, but currently up to 30% of all CRC are recognized to arise from the serrated neoplasia pathway. The primary premalignant lesions are sessile serrated adenomas/polyps (SSA/Ps), although traditional serrated adenomas are relatively uncommon. Compared to conventional adenomas, SSA/Ps are morphologically subtle with indistinct borders, may be difficult to detect endoscopically, are more prevalent than previously thought, are associated with synchronous and metachronous advanced neoplasia, and have a higher risk of incomplete resection. Although many lesions remain “dormant,” progressive disease is associated with the development of dysplasia and more rapid progression to CRC. As a result, SSA/Ps are strongly implicated in the development of interval cancers. These factors represent unique challenges that require a meticulous approach to their management. In this review, we summarize the contemporary literature on the characterization, detection and resection of SSA/Ps.

Clinical characteristics of patients with serrated polyposis syndrome in Korea: comparison with Western patients

BACKGROUND/AIMS: Serrated polyposis syndrome (SPS) has been shown to increase the risk of colorectal cancer (CRC). However, little is known about the characteristics of Asian patients with SPS. This study aimed to identify the clinicopathological features and risk of CRC in Korean patients with SPS as well as the differences between Korean and Western patients based on a literature review. METHODS: This retrospective study included 30 patients with SPS as defined by World Health Organization classification treated at Samsung Medical Center, Korea, between March 1999 and May 2011. RESULTS: Twenty patients (67%) were male. The median patient age at diagnosis was 56 years (range, 39–76 years). A total of 702 polyps were identified during a median follow-up of 43 months (range, 0–149 months). Serrated polyps were noted more frequently in the distal colon (298/702, 55%). However, large serrated polyps and serrated adenomas were mainly distributed throughout the proximal colon (75% vs. 25% and 81% vs. 19%, respectively); 73.3% had synchronous adenomatous polyps. The incidence of CRC was 10% (3/30 patients), but no interval CRC was detected. A total of 87% of the patients underwent esophagogastroduodenoscopy and 19.2% had significant lesions. CONCLUSIONS: The phenotype of SPS in Korean patients is different from that of Western patients. In Korean patients, SPS is more common in men, there were fewer total numbers of serrated adenoma/polyps, and the incidence of CRC was lower than that in Western patients. Korean patients tend to more frequently have abnormal gastric lesions. However, the prevalence of synchronous adenomatous polyps is high in both Western and Korean patients.

Characteristics and outcomes of endoscopically resected colorectal cancers that arose from sessile serrated adenomas and traditional serrated adenomas

BACKGROUND/AIMS: The efficacy and safety of endoscopic resection of colorectal cancer derived from sessile serrated adenomas or traditional serrated adenomas are still unknown. The aims of this study were to verify the characteristics and outcomes of endoscopically resected early colorectal cancers developed from serrated polyps. METHODS: Among patients who received endoscopic resection of early colorectal cancers from 2008 to 2011, cancers with documented pre-existing lesions were included. They were classified as adenoma, sessile serrated adenoma, or traditional serrated adenoma according to the baseline lesions. Clinical characteristics, pathologic diagnosis, and outcomes were reviewed. RESULTS: Overall, 208 colorectal cancers detected from 198 patients were included: 198 with adenoma, five with sessile serrated adenoma, and five with traditional serrated adenoma. The sessile serrated adenoma group had a higher prevalence of high-grade dysplasia (40.0% vs. 25.8%, P<0.001) than the adenoma group. During follow-up, local recurrence did not occur after endoscopic resection of early colorectal cancers developed from serrated polyps. In contrast, two cases of metachronous recurrence were detected within a short follow-up period. CONCLUSIONS: Cautious observation and early endoscopic resection are recommended when colorectal cancer from serrated polyp is suspected. Colorectal cancers from serrated polyp can be treated successfully with endoscopy.

Serrated Adenoma with Adenocarcinoma of Stomach Treated by Endoscopic Submucosal Dissection

Since the first case of gastric serrated adenoma found in 2001, 35 additional cases have been reported. Among these cases, 26 cases were associated with invasive adenocarcinoma within the serrated adenoma. Gastric serrated adenoma when compared with traditional adenoma has close correlation with invasive carcinoma. Serrated colorectal polyps are classified as hyperplastic polyps, sessile serrated adenoma/polyps, and tranditional serrated adenoma (TSA) depending on histological features. Two distinct phenotypes of TSA in the colon and rectum are reported. Those are unlocked serrated crypts (US-TSA) and ectopic crypt formations (ECFs). All gastric serrated adenoma are TSA in historical aspect and ECFs on phenotype. Whereas gastric adenomas are reported with high frequency in the antrum, gastric serrated adenomas are founded in the body and cardia. We report a case of a 60-year-old woman receiving endoscopic submucosal dissection for gastric serrated adenoma with adenocarcinoma discovered during routine screening.

Endoscopic and pathological features of colorectal serrated adenoma: comparison with traditional adenoma / 中华消化内镜杂志

Objective To analyze the differences in endoscopic and pathological features between colorectal serrated adenoma (SA) and colorectal traditional adenoma.Methods The endoscopic and pathological features of 80 cases of SA and 160 cases of traditional adenoma diagnosed from June 2008 to October 2013 were retrospectively analyzed.Results The SA patients were younger than the traditional adenoma patients (57.5 VS 62.3,P =0.003 8).The lesions of SA were mostly located in rectosigmoid colon (60％),while the traditional adenoma could be found in rectosigmoid colon (45％),ascending colon (20％) and descending colon (19％).There were significant differences in the lesion's location between two kinds of adenoma (P ＜ 0.05).There were no differences in gender,the size of lesion or endoscopic classification.In terms of the pathological features,SA had the serrated structure,whereas tubular,tubulovillous and villous structure were found in traditional adenoma.Cancer could be found in 1.9％ of SA,which was lower than that of traditional adenoma (P ＜ 0.05).Conclusion Serrated adenoma is different from traditional adenoma on the patient's age,lesion's location and pathological features.It is an unique kind of adenoma with potential malignancy,which should be emphasized in clinical practice.

Pathogenesis and Management of Serrated Polyps: Current Status and Future Directions

Hyperplastic or serrated polyps were once believed to have little to no clinical significance. A subset of these polyps are now considered to be precursors to colorectal cancers (CRC) in the serrated pathway that may account for at least 15% of all tumors. The serrated pathway is distinct from the two other CRC pathways and involves an epigenetic hypermethylation mechanism of CpG islands within promoter regions of tumor suppressor genes. This process results in the formation of CpG island methylator phenotype tumors. Serrated polyps are divided into hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas (TSAs). The SSA/P and the TSA have the potential for dysplasia and subsequent malignant transformation. The SSA/Ps are more common and are more likely to be flat than TSAs. Their flat morphology may make them difficult to detect and thus explain the variation in detection rates among endoscopists. Challenges for endoscopists also include the difficulty in pathological interpretation as well surveillance of these lesions. Furthermore, serrated polyps may be inadequately resected by endoscopists. Thus, it is not surprising that the serrated pathway has been linked with interval cancers. This review will provide the physician or clinician with the knowledge to manage patients with serrated polyps.

Comparison of telomerase, p53 and Ki-67 expression on colorectal serrated adenoma, traditional adenoma and colorectal cancer / 中国癌症杂志

Background and purpose:Colorectal serrated adenoma (SA) was ofifcially named in 2000 by the WHO as a separate disease, with unique properties compared with traditional adenoma (TA), and its relationship with colorectal cancer (CRC) is very concerned. This study was to analyze and compare the telomerase, p53 and Ki-67 immunohistochemical expression on the tissues of SA, TA and CRC. Methods:Immunohistochemistry was adopted to analyze the expression of telomerase, p53, and Ki-67 in 37 cases of SA, 36 cases of TA and 34 cases of CRC. Results:The p53-positive percentage of SA was signiifcantly lower than that of TA (P<0.01), and the p53-positive percentage of TA was signiifcantly lower than that of CRC (P<0.01). No signiifcant difference of Ki-67 expression was found between SA and TA, and the Ki-67-positive percentage of SA and TA was lower than that of CRC (P<0.01). The telomerase-positive percentage of TA was signiifcantly lower than that of SA (P<0.01), and the telomerase-positive percentage of SA was signiifcantly lower than that of CRC (P<0.05). Conclusion:Telomerase, P53, and Ki-67 immunohisto chemical analysis indicated that SA is a kind of proliferative adenoma, and telomerase activation may play a role in the cancer process.

Cronkhite-Canada Syndrome Associated with Serrated Adenoma and Malignant Polyp: A Case Report and a Literature Review of 13 Cronkhite-Canada Syndrome Cases in Korea

Cronkhite-Canada syndrome (CCS) is a rare nonfamilial polyposis syndrome characterized by epithelial disturbances both in the gastrointestinal tract and in the epidermis. The pathologic finding of the polyp is usually a hamartomatous polyp of the juvenile type; however, the possibility of serrated adenoma associated malignant neoplasm was reported in some Japanese cases. Up till now in South Korea, 13 CCS cases have been reported, but there was no case accompanied by the colon cancer. We report the first case of CCS associated with malignant colon polyp and serrated adenoma in Korea. A 72-year-old male patient who complained of diarrhea and weight loss was presented with both hands and feet nail dystrophy, hyperpigmentation, and alopecia. Endoscopic examination showed numerous hamartomatous polyps from the stomach to the colon. The pathologic results confirmed colon cancer and serrated adenoma. Helicobacter pylori eradication and prednisolone was used. Thus, the authors report this case along with a literature review.

Immunohistochemical Expression of p53, Bcl-2, and Ki-67 Proteins in Traditional Serrated Adenomas of Colon / 대한소화기학회지

BACKGROUND/AIMS: Serrated adenomas of the colon show mixed characteristics of both hyperplastic and adenomatous polyps. Serrated adenomas are known to progress via the serrated pathway than the adenoma-carcinoma pathway. The aim of this study was to evaluate the characteristics of traditional serrated adenomas compared to hyperplastic polyps and tubular adenomas by using immunohistochemical staining for p53, Bcl-2, and Ki-67. METHODS: Age, sex, location, size and the immunoexpression of p53, Bcl-2, and Ki-67 were retrospectively analyzed in 20 traditional serrated adenomas, 20 hyperplastic polyps, and 20 tubular adenomas from January 2007 to December 2012 at The Catholic University of Korea, Yeouido St. Mary's Hospital. RESULTS: There was no difference in Bcl-2 and p53 expression between traditional serrated adenomas and hyperplastic polyps. Ki-67 Expression of traditional serrated adenomas was higher than that of hyperplastic polyps (p=0.001). Ki-67 and p53 expression was similar between traditional serrated and tubular adenomas. Bcl-2 expression of traditional serrated adenomas was lower than that of tubular adenomas (p=0.001). Regarding the expression of p53, Bcl-2, and Ki-67 in traditional serrated adenomas, there were no statistical differences among age, sex, location, and size. CONCLUSIONS: Our study suggested that Ki-67 may be helpful in distinguishing traditional serrated adenomas from hyperplastic polyps, and p53 expression may be ineffective in distinguishing between traditional serrated and tubular adenomas. From Bcl-2 expression, it is suggested that the tumorigenesis of traditional serrated adenomas is lower than that of tubular adenomas.

Immunohistochemical Expression of p53, Bcl-2, and Ki-67 Proteins in Traditional Serrated Adenomas of Colon / 대한소화기학회지

BACKGROUND/AIMS: Serrated adenomas of the colon show mixed characteristics of both hyperplastic and adenomatous polyps. Serrated adenomas are known to progress via the serrated pathway than the adenoma-carcinoma pathway. The aim of this study was to evaluate the characteristics of traditional serrated adenomas compared to hyperplastic polyps and tubular adenomas by using immunohistochemical staining for p53, Bcl-2, and Ki-67. METHODS: Age, sex, location, size and the immunoexpression of p53, Bcl-2, and Ki-67 were retrospectively analyzed in 20 traditional serrated adenomas, 20 hyperplastic polyps, and 20 tubular adenomas from January 2007 to December 2012 at The Catholic University of Korea, Yeouido St. Mary's Hospital. RESULTS: There was no difference in Bcl-2 and p53 expression between traditional serrated adenomas and hyperplastic polyps. Ki-67 Expression of traditional serrated adenomas was higher than that of hyperplastic polyps (p=0.001). Ki-67 and p53 expression was similar between traditional serrated and tubular adenomas. Bcl-2 expression of traditional serrated adenomas was lower than that of tubular adenomas (p=0.001). Regarding the expression of p53, Bcl-2, and Ki-67 in traditional serrated adenomas, there were no statistical differences among age, sex, location, and size. CONCLUSIONS: Our study suggested that Ki-67 may be helpful in distinguishing traditional serrated adenomas from hyperplastic polyps, and p53 expression may be ineffective in distinguishing between traditional serrated and tubular adenomas. From Bcl-2 expression, it is suggested that the tumorigenesis of traditional serrated adenomas is lower than that of tubular adenomas.

Sessile Serrated Adenoma with High-grade Dysplasia / 이화의대지

Until recently, colorectal polyps were classified predominantly as hyperplastic or adenomatous. While adenomatous polyps are well-characterized precursor lesions of adenocarcinomas, hyperplastic polyps have been considered as benign lesion. However, some hyperplastic polyps with serrated morphology of the crypts have been recognized to have distinctive features and these polyps were termed 'serrated adenomas'. Recent data show that sessile serrated adenomas (SSA) might be the precursors of serrated colonic cancers, underlining the necessity of identifying them. SSA is approximately 3% of all polyps, commonly appears as flat or sessile and yellowish due to mucus production. In the pathogenesis of SSA, progression to high grade dysplasia or early invasive carcinoma may be associated with serrated neoplasia pathway different from adenoma-carcinoma sequence. We report a case with a colon polyp diagnosed as sessile serrated adenoma with high grade dysplasia after endoscopic submucosal dissection.