Absence of MutY homologue mutation in patients with multiple sporadic adenomatous polyps in Korea

AIM： Recently, germ-line mutation in the base excision repair gene MYH has been identified to cause a novel autosomal recessive form of familial adenomatous polyposis （FAP）. Interestingly, a striking evidence for MYH mutations within different ethnic groups has been demonstrated. In this study, we screened 30 patients with multiple adenomatous polyps for MYH mutations to assess its prevalence and ethnic specificity in Korea. METHODS： Thirty patients （21 men and 9 women; mean age 62.3 years） with multiple adenomatous polyps were examined for MYH mutations. The mean number of adenomas per patient was 10.0. Sixteen exonic regions and their intronic sequences were amplified by PCR and subjected to SSCP and DNA sequencing analyses. RESULTS： None of the patients was identified to carry any truncating or sequence alterations in MYH. Our screening for the mutational regions, which were recognized from Caucasian patients or affected Indian families, also failed to detect sequence substitutions. CONCLUSION： Mutation in MYHmay be rarely involved in the pathogenesis of multiple sporadic colorectal adenomas in Korean population, although a large-scale analysis will be required to clarify the presence of specific MYH variants in a subset of patients and their role in the predisposition of multiple colorectal adenomas in Korean population.

Fecal metabolomic profiles: A comparative study of patients with colorectal cancer vs adenomatous polyps

BACKGROUND Colorectal cancer(CRC),the third most common cause of death in both males and females worldwide,shows a positive response to therapy and usually a better prognosis when detected at an early stage.However,the survival rate declines when the diagnosis is late and the tumor spreads to other organs.Currently,the measures widely used in the clinic are fecal occult blood test and evaluation of serum tumor markers,but the lack of sensitivity and specificity of these markers restricts their use for CRC diagnosis.Due to its high sensitivity and precision,colonoscopy is currently the gold-standard screening technique for CRC,but it is a costly and invasive procedure.Therefore,the implementation of custom-made methodologies including those with minimal invasiveness,protection,and reproducibility is highly desirable.With regard to other screening methods,the screening of fecal samples has several benefits,and metabolomics is a successful method to classify the metabolite shift in living systems as a reaction to pathophysiological influences,genetic modifications,and environmental factors.AIM To characterize the variation groups and potentially recognize some diagnostic markers,we compared with healthy controls(HCs)the fecal nuclear magnetic resonance(NMR)metabolomic profiles of patients with CRC or adenomatous polyposis(AP).METHODS Proton nuclear magnetic resonance spectroscopy was used in combination with multivariate and univariate statistical approaches,to define the fecal metabolic profiles of 32 CRC patients,16 AP patients,and 38 HCs well matched in age,sex,and body mass index.RESULTS NMR metabolomic analyses revealed that fecal sample profiles differed among CRC patients,AP patients,and HCs,and some discriminatory metabolites including acetate,butyrate,propionate,3-hydroxyphenylacetic acid,valine,tyrosine and leucine were identified.CONCLUSION In conclusion,we are confident that our data can be a forerunner for future studies on CRC management,especially the diagnosis and evaluation of the effectiveness of treatments.

Sex-influenced association of non-alcoholic fatty liver disease with colorectal adenomatous and hyperplastic polyps

AIM To investigate the relationship between non-alcoholic fatty liver disease(NAFLD) and colorectal adenomatous and hyperplastic polyps.METHODS A retrospective cross-sectional study was conducted on 3686 individuals undergoing health checkups(2430 males and 1256 females). All subjects underwent laboratory testing,abdominal ultrasonography,colonoscopy,and an interview to ascertain the baseline characteristics and general state of health. Multinomial logistic regression analysis was performed to examine the association between NAFLD and the prevalence of colorectal adenomatous and hyperplastic polyps.Furthermore,the relationship was analyzed in different sex groups. Subgroup analysis was performed based on number,size,and location of colorectal polyps.RESULTS The prevalence of colorectal polyps was 38.8% in males(16.2% for adenomatous polyps and 9.8% for hyperplastic polyps) and 19.3% in females(8.4% for adenomatous polyps and 3.9% for hyperplastic polyps). When adjusting for confounding variables,NAFLD was significantly associated with the prevalence of adenomatous polyps(OR = 1.28,95%CI: 1.05-1.51,P < 0.05) and hyperplastic polyps(OR = 1.35,95%CI: 1.01-1.82,P < 0.05). However,upon analyzing adenomatous and hyperplastic polyps in different sex groups,the significant association remained in males(OR = 1.53,95%CI: 1.18-2.00,P < 0.05; OR = 1.42,95%CI: 1.04-1.95,P < 0.05) but not in females(OR = 0.44,95%CI: 0.18-1.04,P > 0.05; OR = 1.18,95%CI: 0.50-2.78,P > 0.05). CONCLUSION NAFLD is specifically associated with an increased risk of colorectal adenomatous and hyperplastic polyps in men. However,NAFLD may not be a significant factor in the prevalence of colorectal polyps in women.

Study of Differential Serum Metabolites in Patients with Adenomatous Polyps of Colon and Yang-Deficiency Constitution Based on Ultra-Performance Liquid Chromatography-Mass Spectrometry

Objective:To study the differences between the serum metabolites in patients with adenomatous polyps of the colon and yang-deficiency constitution and those without colon polyps and with balanced constitution,and look for biomarkers that can be used to distinguish between the two groups.Methods:General patient information was gathered,and Chinese medicine constitutions were collected in 940 patients who underwent electronic colonoscopy.A total of 119 patients with adenomatous polyps of the colon and yang-deficiency constitution were included in the experimental group,and 150 patients without colon polyps and with balanced constitution were included in the control group.Metabolomics analysis was performed on the fasting venous blood obtained from each patient in both groups.Principal component analysis and orthogonal partial least squares discriminant analysis were performed on the detection results,potential biomarkers were screened,metabolic pathway changes were determined,and the metabolic processes involved were discussed.Results:A total of 59 differential biomarkers between the experimental group and the control group were identified.The differential metabolites were found mainly in the glycerophospholipid metabolism pathway,and the bile acid 3-oxo-4,6-choladienoic acid was the biomarker that distinguished the experimental group from the control group.Conclusions:With the help of metabolomics analysis,the differential metabolites in patients with adenomatous polyps of the colon and yang-deficiency constitution and those in patients without colon polyps and with balanced constitution could be identified.The biomarker 3-oxo-4,6-choladienoic acid may have potential diagnostic value in patients with adenomatous polyp of the colon and yang-deficiency constitution.(Trial Registration No.NCT02986308)

Cronkhite-Canada Syndrome:an unusual finding of gastro-intestinal adenomatous polyps in a syndrome characterized by hamartomatous polyps

Cronkhite-Canada syndrome is a rare,hamartomatous polyposis syndrome of unknown etiology.Hamartomatous gastrointestinal polyps,alopecia,onychodystrophy,cutaneous hyperpigmentation,abdominal pain,diarrhea,and complications of weight loss are typical of the syndrome.In this report,we describe a pathological finding of colonic adenomatous polyposis as opposed to hamartomatous polyposis.We also describe our treatment,long-term therapeutic plan,and the need for further research.

Expanding endoscopic boundaries:Endoscopic resection of large appendiceal orifice polyps with endoscopic mucosal resection and endoscopic submucosal dissection

BACKGROUND Large appendiceal orifice polyps are traditionally treated surgically.Recently,endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)have been utilized as alternative resection techniques.AIM To evaluate the efficacy and safety of endoscopic resection techniques for the management of large appendiceal orifice polyps.METHODS This was a retrospective observational study conducted to assess the feasibility and safety of EMR and ESD for large appendiceal orifice polyps.This project was approved by the Baylor College of Medicine Institutional Review Board.Patients who underwent endoscopic resection of appendiceal orifice polyps≥1 cm from 2015 to 2022 at a tertiary referral endoscopy center in the United States were enrolled.The main outcomes of this study included en bloc resection,R0 resection,post resection adverse events,and polyp recurrence.RESULTS A total of 19 patients were identified.Most patients were female(53%)and Caucasian(95%).The mean age was 63.3±10.8 years,and the average body mass index was 28.8±6.4.The mean polyp size was 25.5±14.2 mm.74%of polyps were localized to the appendix(at or inside the appendiceal orifice)and the remaining extended into the cecum.68%of polyps occupied≥50%of the appendiceal orifice circumference.The mean procedure duration was 61.6±37.9 minutes.Polyps were resected via endoscopic mucosal resection,endoscopic submucosal dissection,and hybrid procedures in 5,6,and 8 patients,respectively.Final pathology was remarkable for tubular adenoma(n=10)[one with high grade dysplasia],sessile serrated adenoma(n=7),and tubulovillous adenoma(n=2)[two with high grade dysplasia].En bloc resection was achieved in 84%with an 88%R0 resection rate.Despite the large polyp sizes and challenging procedures,89%(n=17)of patients were discharged on the same day as their procedure.Two patients were admitted for post-procedure observation for conservative pain management.Eight patients underwent repeat colonoscopy without evidence of residual or recurrent adenomatous polyps.CONCLUSION Our study highlights how endoscopic mucosal resection,endoscopic submucosal dissection,and hybrid procedures are all appropriate techniques with minimal adverse effects,further validating the utility of endoscopic procedures in the management of large appendiceal polyps.

Should we perform sigmoidoscopy for colorectal cancer screening in people under 45 years?

BACKGROUND The strategy for preventing colorectal cancer is screening by colonoscopy,which offers a direct way for detection and removal of adenomatous polyps(APs).American College of Gastroenterology guidelines recommend that people aged≥45 years should undergo colonoscopy;however,how to deal with people aged≤45 years is still unknown.AIM To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients≤45 years.METHODS A retrospective observational study was conducted at a single tertiary III hospital in China.This study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January 2021.The number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were evaluated.RESULTS A total of 3053 cases were included.The prevalence of APs in the left and right colon was 55.0%and 41.6%,respectively(OR 1.7,95%CI 1.6-2.4;P<0.05).For APs with high-grade neoplasia,the prevalence was 2.7%and 0.9%,respectively(OR 3.0,95%CI 2.0-4.6;P<0.05).Therefore,the prevalence of APs and high-grade neoplasia in the left colon was significantly higher than in the right colon in patients aged≤45 years.There were 327 patients who voluntarily participated in post-polypectomy surveillance in following 1-3 years,and APs were found in 216 cases(66.1%);170 cases had 1-3 polyps(52.0%)and 46 cases had>3 polyps(14.1%;OR 0.3,95%CI 0.1-0.6;P<0.05).CONCLUSION This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged≤45 years and would be a more cost-effective and safe strategy.

Role of high definition colonoscopy in colorectal adenomatous polyp detection

AIM:To investigate the rates of polyp detection in a mixed risk population using standard definition (SDC) vs high definition colonoscopes (HDC).METHODS:This was a retrospective cohort comparative study of 3 colonoscopists who each consecutively performed 150 SDC (307,200 pixel) and 150 HDC (792,576 pixels) in a community teaching hospital.RESULTS:A total of 900 colonoscopies were evaluated (mean age 56,46.8% men),450 with each resolution.Polyps of any type were detected in 46.0% of patients using SDC and 43.3% with HDC (P=0.42).There was no significant difference between the overall number of polyps,HDC (397) and SDC (410),detected among all patients examined,(P=0.73).One or more adenomatous polyps were detected in 24.2% of patients with HDC and 24.9% of patients with SDC colonoscopy (P=0.82).There was no significant difference between HDC (M=0.41) and SDC (M=0.42) regarding adenomatous polyp (P=0.88) or advanced adenoma (P=0.56) detection rate among all patients examined.CONCLUSION:HDC did not improve yield of adenomatous polyp,advanced adenoma or overall polyp detection in a population of individuals with mixed risk for colorectal cancer.

Clinical predictors of colorectal polyps and carcinoma in a low prevalence region: Results of a colonoscopy based study

AIM: To estimate the prevalence of colorectal cancer (CRC) in patients with long lasting colonic symptoms undergoing total colonoscopy; and to establish clinical features predicting its occurrence. METHODS: This prospective study was carried out in Imam Hospital, Tabriz University of medical sciences, Iran. Continuous patients with long lasting lower gastrointestinal tract symptoms who had the criteria of a colonoscopy were included. The endoscopist visualized the caecum documented by a photo and/or a specimen from terminal ileum. RESULTS: Four hundred and eighty consecutive symptomatic patients [mean age (SD): 42.73 (16.21)] were included. The prevalence of colorectal neoplasia was 15.3% (34 subjects) and 37.7% (181 subjects) had a completely normal colon. Adenomatous polyps were detected in 56 (11.7%) patients, in 12.3% of men and 10.9% of women. The mean age of the patients with a polyp was significantly higher than the others (49.53 ± 14.16 vs 41.85 ± 16.26, P = 0.001). Most of the adenomatous polyps were left sided and tubular; only 22.5% of polyps were more than 10 mm. Cancer was detected in 16 (3.6%) of our study population, which was mostly right sided (57.2%). The mean age of patients with cancer was significantly higher than the others (60.25 ± 8.26 vs 42.13 ± 16.08, P < 0.005) and higher than patients with polyps [60.25 (8.26) vs 49.53 (1.91) (P < 0.0005)]. None of the symptoms (diarrhea, abdominal pain, rectal bleeding, constipation, altering diarrhea and constipation, history of cancer, known irritable bowel disease, history of polyp and fissure or family history of cancer) were predictors for cancer or polyps, but the age of the patient and unexplainedanemia independently predicted cancer. CONCLUSION: Less advanced patterns and smaller sizes of adenomas in Iran is compatible with other data from Asia and the Middle East, but in contrast to western countries. Prevalence of colonic neoplasia in our community seems to be lower than that in western population. Colonic symptoms are not predictors for polyps or cancer but unexplained anemia and elder age can predict CRC.

Colorectal cancer disparities: Issues, controversies and solutions

Colorectal cancer(CRC)is the second leading cause of cancer related deaths in the United States.There are significant differences in CRC incidence and mortality by race with the highest burden occurring among blacks.The underlying factors contributing to CRC disparities are multiple and complex.Studies have suggested that a higher prevalence of putative risk factors for CRC,limited access to healthcare services,lower utilization of healthcare resources and increased biological susceptibilities contribute to this disparity by race.This article reviews the factors associated with the disproportionally higher burden of CRC among blacks;addresses the controversies regarding the age to begin CRC screening and the screening modality to use for blacks;and proffers solutions to eliminate CRC disparity by race.

Screening colonoscopy:The present and the future

In the United States,colorectal cancer(CRC)is the second leading cause of mortality in men and women.We are now seeing an increasing number of patients with advanced-stage diagnosis and mortality from colorectal cancer before 50 years of age,which requires earlier screening.With the increasing need for CRC screening through colonoscopy,and thus endoscopists,easier and simpler techniques are needed to train proficient endoscopists.The most widely used approach by endoscopists is air insufflation colonoscopy,where air distends the colon to allow visualization of the colonic mucosa.This technique is uncomfortable for patients and requires an anesthetist to administer sedation.In addition,patients commonly complain about discomfort post-op as air escapes into the small bowel and cannot be adequately removed.Current research into the use of water insufflation colonoscopies has proved promising in reducing the need for sedation,decreasing discomfort,and increasing the visibility of the colonic mucosa.Future direction into water insufflation colonoscopies which have shown to be simpler and easier to teach may increase the number of proficient endoscopists in training to serve our aging population.

Incidence of colorectal neoplasms among male pilots

AIM: To assess the prevalence of colorectal neoplasms (adenomas, advanced adenomas and colorectal cancers) among Israeli military and commercial airline pilots.