Prevalence Of Adenomatous Polyps Research Articles

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

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. To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients ≤ 45 years. 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. 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). 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.

Association of nonalcoholic fatty liver disease with colorectal adenomatous polyps and non-adenomatous polyps: a cross-sectional study.

This study aimed to investigate the association between non-alcoholic fatty liver disease (NAFLD) and both colorectal adenomatous polyps and non-adenomatous polyps, in order to provide evidence for the prevention of colorectal cancer (CRC) in patients with NAFLD. A retrospective, cross-sectional study was conducted at the First People's Hospital of Kunshan, Jiangsu, China. The study included 3028 adults who underwent abdominal ultrasonography and colonoscopy over a 5 year period. We compared characteristics among patients with adenomatous polyps, non-adenomatous polyps, and without colorectal polyps using descriptive statistics. Logistic regression analyses were used to detect associations between NAFLD with the prevalence of adenomatous polyps and non-adenomatous polyps. NAFLD was determined by abdominal ultrasound. Colorectal polyps were assessed by data in the colonoscopy report and pathology report. A total of 65% of patients with NAFLD had colorectal polys (52% adenomatous polyps and 13% non-adenomatous polyps), and 40% of patients without NAFLD had polyps (29% adenomatous polyps and 11% non-adenomatous polyps). After adjusting for confounding variables, NAFLD was significantly associated with the prevalence of adenomatous in males and females [odds ratio (OR) = 1.8, 95% confidence interval (CI): 1.6-2.2, P < 0.01], but was not associated with non-adenomatous polyps (OR = 1.2, 95% CI:0.9-1.5, P > 0.05). NAFLD is associated with an increased risk of colorectal adenomatous polyps compared to the absence of polyps, but not associated with an increased risk of non-adenomatous polyps. These results provide important evidence for the prevention of CRC in patients with NAFLD.

S3272 Prevalence of Colonic Adenomas in Cirrhotic Patients Undergoing Pre-Transplant Evaluation: A Meta-Analysis and Systematic Review

INTRODUCTION: Multiple studies have suggested that the risk of advanced adenomas and colorectal cancer is not only higher in liver transplant patients, but also significantly increases post transplantation, particularly due to their immunocompromised state. As it stands, CRC screening recommendations in low to moderate risk liver transplant candidates are the same for those of the general population. This study aims to analyze the literature on the prevalence of adenomas in liver cirrhosis patients undergoing colonoscopy screening as part of their pre-transplant evaluation. METHODS: A systemic review was conducted in PUBMED, Embase, PubMed Central and ScienceDirect databases from inception through May 2020. Effect estimates from the individual studies were extracted and combined using the random effect, generic inverse variance method of DerSimonian and Laird and pooled event rates were calculated. Forest plots were generated, and publication bias was assessed for using conventional techniques. RESULTS: Eleven studies with a total of 4223 patients with cirrhosis undergoing liver transplant evaluation were included in this analysis. The pooled event rate for any adenoma was 21.2% (95% CI, 16.9%–26.2%), whereas the pooled event rate for advanced adenoma was 5.6% (95% CI, 2.7%–11.4%). The pooled event rate for adenocarcinoma was 0.7% (95% CI, 0.03%–1.7%), most of which were successfully resected endoscopically. CONCLUSION: This study suggests a considerable prevalence of adenomatous polyps and advanced lesions in this high-risk patient population, and hence, colonoscopy should be performed for every transplant candidate within the frame of the current ACG recommendations. Additionally, our results call for further risk-matched prospective studies to examine the need for earlier endoscopic surveillance in this cohort of patients.Figure 1.: Forrest plot, pooled event rate of any adenoma in cirrhotic patients undergoing transplant evaluation.Figure 2.: Forrest plot, pooled event rate of advanced adenomas in cirrhotic patients undergoing transplant evaluation.Figure 3.: Forrest plot, pooled event rate of adenocarcinoma in cirrhotic patients undergoing transplant evaluation.

Adenoma Detection Rates in Patients in the 40-49 Year Age Group Across Different Ethnicities: Presidential Poster Award

Introduction: Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the third leading cause of cancer related deaths in United States. Recent guidelines from the American Cancer Society (ACS) recommend starting CRC screening at 45 years in average-risk patient population in United States. Previous studies have shown an increase in incidence of CRC in African Americans less than 50 years of age. Despite this, there is limited evidence about prevalence of adenomatous polyps in this age group. We aimed to examine the prevalence of adenomas in 40 to 49 years old patients without any family history (FH) of CRC or polyps across different races. Methods: A retrospective cross sectional study was performed using our electronic endoscopy database. Study subjects included all 40 to 49-year-old patients without any FH of CRC undergoing their index colonoscopy at our tertiary care academic institution from January 1, 2010 to September 30, 2017. Exclusion criteria included patients who underwent colonoscopy for overt gastrointestinal bleeding, inflammatory bowel disease, patients who had previous colonoscopies, a history of familial adenomatous polyposis, hereditary non polyposis CRC. Results: A total of 1856 patients were included in the study. Of these 53.6 % were Caucasian, 26.9% African Americans, and 19.4 % were Hispanics. Mean age of these patients was 44.7 yrs (S.D 2.6) and 57.6 % were males. Adenoma detection rate (ADR) was 22.1 % in Caucasians, 16.0 % in African Americans, 23.3% in Hispanics (Table 1). On multivariate analysis while adjusting for possible confounding factors, African Americans had lower ADR as compared to Caucasians (adjusted Odds Ratio: 0.6, 95% CI: 0.4-0.8, P-value=0.001). Conclusion: The ADR across all races in the 40-49 year age group is lower than the previously recommended ADR in patients with average risk undergoing their screening colonoscopy at 50 years of age (i.e. 25%). With the advent of new guidelines from the ACS, new benchmarks for quality indicators in colonoscopy regarding ADR will be needed. The lower ADR in African Americans suggests that further studies are needed to look for factors beyond the traditional adenoma-carcinoma pathway to understand the increasing incidence of CRC in African Americans in the younger age group.478 Figure 1 No Caption available.

Predicting the presence of adenomatous polyps during colonoscopy with National Cancer Institute Colorectal Cancer Risk-Assessment Tool.

AIMTo evaluate the National Cancer Institute (NCI) Colorectal Cancer (CRC) Risk Assessment Tool as a predictor for the presence of adenomatous polyps (AP) found during screening or surveillance colonoscopy.METHODSThis is a retrospective single center observational study. We collected data of adenomatous polyps in each colonoscopy and then evaluated the lifetime CRC risk. We calculated the AP prevalence across risk score quintiles, odds ratios of the prevalence of AP across risk score quintiles, area under curves (AUCs) and Youden’s indexes to assess the optimal risk score cut off value for AP prevalence status.RESULTSThe prevalence of AP gradually increased throughout the five risk score quintiles: i.e., 27.63% in the first and 51.35% in the fifth quintile. The odd ratios of AP prevalence in the fifth quintile compared to the first and second quintile were 2.76 [confidence interval (CI): 1.71-4.47] and 2.09 (CI: 1.32-3.30). The AUC for all patients was 0.62 (CI: 0.58-0.66). Youden’s Index indicated the optimal risk score cutoff value discriminating AP prevalence status was 3.60.CONCLUSIONPatients with the higher NCI risk score have higher risk of AP and subsequent CRC; therefore, measures to increase the effectiveness of CRC detection in these patients include longer withdrawal time, early surveillance colonoscopy, and choosing flexible colonoscopy over other CRC screening modalities.

Screening Colonoscopies in Patients With HIV: A Retrospective Comparative Study Assessing Rate of Adenomatous Polyps

Introduction: Colon cancer screening strategy in patients with HIV remains controversial. With no sufficient data exist on rates of adenomatous polyps by screening colonoscopies in >50-year-old patients with HIV in the United States. The aim of this study was to obtain such data. Methods: A retrospective chart review of 234 asymptomatic HIV subjects >50 years of age and 396 asymptomatic uninfected control subjects matched for age and sex, who underwent screening colonoscopy. We looked into all adenomatous polyps detected regardless of size, villous histology, left-sided findings versus right-sided findings, or adenocarcinoma. Individuals who had diagnostic colonoscopies or for whom a colonoscopy was performed as a diagnostic procedure were excluded. Results: The prevalence of adenomatous polyps were higher in HIV-infected subjects than in the control subjects but it was not statically significant (35.9% vs. 32.0%: P=0.24). When sub-analyzed, patients with HIV had higher malignant polyps detected than in control group (5 cases vs 0, p =0.003). Graph 1 shows the percentage of polyps detected based on type of polyp. Among patients with HIV, average CD4 counts was 509 in adenomatous polyp group vs 517 in normal mucosal group (P=0.8). Conclusion: We here show a significantly higher malignancy detection rate on screening colonoscopy in patients with HIV when compared to general population. We also show a higher incidence of overall polyp detected in patients with HIV but it was not statically significant. There was no difference between CD4 count and incidence of polyps. Our findings suggest that patients with HIV should be considered in a high-risk group and screened accordingly. The age of initiation and the optimal frequency of screening require further study.Figure

Low frequency of polyps in colonic regions with diverticulosis.

Conflicting evidence exists regarding any association between diverticulosis and adenomatous polyps. We evaluated the prevalence of polyps and cancer in colonic regions containing diverticula. Six hundred consecutive colonoscopy reports from a single endoscopist were reviewed to determine prevalence and location of diverticulosis and polyps. Additionally, pathology reports of 88 colon cancer resection specimens were reviewed for the presence of diverticulosis, and compared with expected prevalence of diverticulosis in that colonic region based on the collected colonoscopy data. Overall, rates of detected polyps were comparable between patients with and without diverticulosis. However, analyzing the data by colonic segment containing diverticulosis, the prevalence of adenomatous polyps was reduced in regions of diverticulosis compared to the same colonic segment unaffected by diverticulosis (7 vs. 17% for rectosigmoid (p=0.005); 5 vs. 18% for descending (p<0.0001); and 17 vs. 27% for ascending colon (p=0.0495)). Among colon cancer resection specimens, the prevalence of diverticulosis was significantly reduced in the rectosigmoid and ascending colon, compared with expected rates of diverticulosis in those regions. (13 vs. 42% in rectosigmoid (p=0.0006); 3 vs. 17% in ascending colon (p=0.043)). Despite similar overall frequency of polyps in patients with and without diverticulosis, polyps were significantly less likely in the colonic segment affected by diverticulosis. Additionally, the frequency of diverticulosis in areas of cancer in the rectosigmoid and ascending colon was significantly lower than expected compared with the expected frequency of diverticulosis for those colonic regions. These observations suggest a true negative association between colonic neoplasia and diverticulosis.

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

AIMTo investigate the relationship between non-alcoholic fatty liver disease (NAFLD) and colorectal adenomatous and hyperplastic polyps.METHODSA 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.RESULTSThe 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).CONCLUSIONNAFLD 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.

High Body Mass Index (BMI) and Smoking as Potential Risk Factors Associated with Adenomatous Polyp Detection in Young Patients

Introduction: Adenomatous polyps (AP) are the most common precursor lesions for colon cancer. Colonoscopy can effectively detect and remove these lesions justifying it an irreplaceable cancer prevention method. The prevalence of AP is variable and an older age is a major risk factor. In fact, AP in young patients (under 40 years old) is quite rare, particularly in individuals without any known genetic syndromes associated with a possible risk of colon cancer. To study associated factors (comorbidities and risk behaviors) in such young patients may help to identify potential new risks factors for colon cancer development. Methods: Thirty-four patients were identified who were under 40 years old and had AP including sessile serrated polyp/adenoma (SSP/A) detected by colonoscopy during the years of 2013 to 2015. Patients age, sex, colonic pathology and location of polyp, and bmi were reviewed. To obtain this information, the review was done in the electronic medical record through review of epic patients' charts and endoscopy reports through Provation Results: Forty- seven percent (16/34) patients were female, sixty percent (18/34) were male. Thirty-two percent of patients (11/34) had polyp sizes less than 5 mm. Forty-seven percent of patients (16/34) had polyp sizes between 5 mm and 10 mm. Twenty-one percent of patients (7/34) had polyp sizes over 10 mm. Twelve percent of patients (4/34) had a BMI less than 24.9. Forty-one percent of patients (14/34) had a BMI between25 and 29.9 classified as overweight. Forty-seven percent of patients (16/34) had a BMI over 30 classified as obese. Fifty three percent of patients (18/34) reported a positive smoking history or were a current smoker. The majority of polyps (56%) (19/34) were detected in the sigmoid colon. Conclusion: Based on this retrospective chart review, in a young patient population (age range between 30-49), a BMI over 25 and a positive smoking history or being a current smoker was associated with a higher likelihood of detection of tubular adenoma on colonscopy. Follow-up surveillance colonscopy intervals were variable, with the most common follow-up interval being approximately 5 years.

Rarity of adenomatous polyps in ulcerative colitis and its implications for colonic carcinogenesis.

Despite ample research on the dysplasia to carcinoma risk in ulcerative colitis, there are scant data on the prevalence of adenomatous polyps in this population. The number and histology of all polyps detected at colonoscopies of ulcerative colitis patients aged > 50 during 2006 - 2012 were compared with similarly aged controls undergoing screening colonoscopy. There were 206 patients with ulcerative colitis and 624 controls included in the study (mean age 61.7 ± 8.7 vs. 60.8 ± 6.1, respectively; P = 0.15). Adenomatous polyps were detected in only 13/206 colonoscopies for ulcerative colitis compared with 162 /624 controls (6.3 % vs. 25.9 %, respectively; odds ratio [OR] 0.19, 95 % confidence interval [CI] 0.1 - 0.34; P < 0.0001). When also considering all prior colonoscopies performed over 7.7 ± 4.6 years of follow-up (mean 4.1 ± 2.9 colonoscopies/patient, range 1 - 15, total 832 colonoscopies), the risk of ever finding an adenoma in ulcerative colitis patients was still significantly lower compared with controls (14.1 % vs. 25.9 %, respectively; OR 0.47, 95 %CI 0.3 - 0.72; P = 0.0005). On multivariable analysis, adenomas were positively associated with advanced age (OR 1.07/year, 95 %CI 1.03 - 1.1; P < 0.0001) and with increasing body mass index (BMI; OR 1.06/kg/m(2), 95 %CI 1.01 - 1.1; P = 0.01) and negatively associated with having ulcerative colitis (OR 0.15, 95 %CI 0.09 - 0.44; P = 0.0005). Among 115 Crohn's disease patients aged > 50 years, the rate of ever-adenomas in small-bowel Crohn's disease was similar to the controls (P = 0.8) and not influenced by 5-aminosalicylic acid use, whereas patients with colonic Crohn's disease had a significantly lower rate of adenomas compared with the controls (3.9 % vs. 25.9 %; P = 0.002). Unlike patients with small-bowel Crohn's disease, patients with ulcerative colitis or with colonic Crohn's disease seldom develop sporadic adenomatous polyps. These data may provide novel clues to a possible role for colonic immune activation in restricting the adenoma to carcinoma sequence while propagating the dysplasia to carcinoma pathway.

PTH-029 Should patients with rectal bleeding having a flexible sigmoidoscopy come fully prepared for a colonoscopy?: Abstract PTH-029 Table 1

<h3>Introduction</h3> The vast majority of patients referred for investigation of rectal bleeding have benign anal disease or proctitis. Flexible sigmoidoscopy (FS) has been widely used for the investigation of patients with rectal bleeding with same day single phospho-soda enema preparation prior to the examination. However, conversion to full colonoscopy is warranted if adenomatous polyps or colon cancer is detected to exclude synchronous lesions. We hypothesise that as the patients age at presentation of rectal bleeding increases, the prevalence of adenomatous polyps and colon cancer increases and thereby the requirement for evaluation of the entire colon. If this is established then we should recommend that patients undergoing FS for rectal bleeding should be scoped with full bowel preparation and converted to a colonoscopy if polyp or cancer is detected at the time of FS. The aim of the study was to assess the diagnostic yield of FS in detecting colon cancer/polyp in patients of different ages presenting with rectal bleeding. <h3>Method</h3> A single centre, retrospective analysis of patients with rectal bleeding investigated with FS in a district general hospital from north London was performed. The patients were identified using the Unisoft Endoscopy reporting software over a period from June 2006 to March 2014. Data obtained during the study period was scrutinised for diagnosis and whether further full colonic imaging was indicated as judged by diagnosis of colon cancer or adenomatous polyp. <h3>Results</h3> 1406 FS were performed in the study period. The table below demonstrates the findings at FS in patients with rectal bleeding according to age category. 25% of patients over 45 years of age have a cancer or polyp diagnosed that requires further full colonic imaging. <h3>Conclusion</h3> 25% of patients over 45 years of age undergoing FS for rectal bleeding have a colon cancer or polyp diagnosed that require further colonic imaging. Preparing all patients for a full colonoscopy at the time of attendance for FS and conversion to colonoscopy if a polyp or cancer is detected would save reattendance in 25% of patients over the age of 45 for rectal bleeding. The prevalence of polyps and cancer however is low in patients under 45 years of age and these patients could continue to have FS with enema preparation just prior to the procedure. <h3>Disclosure of interest</h3> None Declared.

Open-access flexible sigmoidoscopy frequently leads to additional colonoscopy in symptomatic patients over 50 years.

General practitioners (GPs) in the Netherlands have open access to flexible sigmoidoscopy (FS) for patients with lower gastrointestinal symptoms, but not to colonoscopy. This study was performed to investigate the yield of FS in GP-referred patients, to evaluate the proportion of patients in whom additional colonoscopy was performed and to investigate whether there was a subgroup of patients referred for symptoms with a low risk of detecting significant findings. All patients undergoing FS in 2008 and 2009 who were referred by GPs were analyzed. Indications for additional colonoscopy were the presence of polyps and/or colorectal cancer (CRC), polyp screening or surveillance, incomplete FS or other reasons. In total, 916 patients underwent FS. A cause for the symptoms was found in 44.2% of patients. In patients aged 50 years or older, additional colonoscopy was more frequently performed than in younger patients (27.5% vs. 9.6%, OR=3.6 [95% CI 2.4-5.4]), mainly due to a higher prevalence of adenomatous polyps (29.9% vs. 10.5%, OR=3.6 [95% CI 2.4-5.4]) and CRC (7.5% vs. 1.3%, OR=6.2 [95% CI 2.2-17.5]) during FS. In 7.8% patients undergoing FS for abdominal pain as the presenting symptom, a probable cause for the symptoms was found, mainly diverticular disease. Due to the high prevalence of polyps and CRC in symptomatic patients aged 50 years or older undergoing FS, an additional colonoscopy is performed frequently. In patients referred with abdominal pain, FS is unlikely to reveal a relevant cause for the symptoms.

Tu1518 Total Colonoscopy for Positive Fecal Occult Blood Test: Could It Be Replaced With Sigmoidoscopy?

(9) (pZ0.06; OR, 1.8; 95%CI 1-3.3). IBD was most likely to be diagnosed in patients younger than 40 years, 83.3% (10) vs. 16.3% (2) (pZ0.003; OR, 3.6; 95%CI 1.1-12.8). CRC was more frequent over 40; 72% (10) vs. 28% (4) (pZ0.6; OR, 1.3; 95%CI, 0.8-2.9), as well as adenomatous polyps who were also more common in this age group; 70.4% (69) vs. 29.6% (28) (pZ0.0.2; OR, 1.8; 95%CI: 1.1-2.9). Conclusion: We found a high prevalence of significant lesions (20.8%), especially adenomatous polyps and CRC, who combined for 18.8% (16.4% and 2.4% respectively). These lesions were more common in patients older than 40 years, mainly distal to the splenic flexure. This would suggest that these lesions could have been diagnosed by a sigmoidoscopy. Despite this and given the high prevalence of adenomatous polyps and CRC found in patients over 40, is that we believe that colonoscopy should be recommended in this age group. Table 1. Lesions found on colonoscopy

Screening colonoscopy in the initial workup of bariatric surgery patients: guidelines are needed

Cancer is one of the most common causes of death among morbidly obese individuals. Obese individuals have a well-documented increased risk of colon cancer. No guidelines are available for the workup of bariatric surgery patients in relation to colon cancer. The indications for screening colonoscopy at the Bariatric and Metabolic Institute Abu Dhabi (BMI Abu Dhabi) include all patients older than 50 years [40 years if patients are United Arab Emirates (UAE) nationals] with unexplained abdominal symptoms, anemia of unknown cause, or a family or personal history of colonic pathology. This study retrospectively reviewed the charts of all the patients who had colonoscopy during the period January 2009 to January 2013. The patients were divided into two groups: group A [patients with a body mass index (BMI) > 30 kg/m(2)] and group B (patients with a BMI < 30 kg/m(2)). The demographics and the prevalence of polyps and cancer in the two groups were compared. During the study period, 341 colonoscopies were performed: 137 for patients with a BMI higher than 30 kg/m(2) (mean age, 44 years) and 204 for patients with a BMI lower than 30 kg/m(2) (mean age, 46 years) (P > 0.05). The overall prevalence of adenomatous polyps was 6.74 % and that of cancer was 1.75 %. Further analysis showed that the prevalences of adenomatous polyps and cancer were respectively 12.4 and 2.1 % for the patients with a BMI higher than 30 kg/m(2), whereas the prevalences were respectively 2.9 and 0.9 % for the patients with BMI lower than 30 kg/m(2) (P < 0.001). The risk for the development of colonic adenomatous polyps and cancer is high among young obese individuals in the Middle East. Guidelines are needed to establish criteria for screening in this group of individuals.

Su1075 Colorectal Neoplasia Risk in Inflammatory Bowel Disease Accompanying Primary Sclerosing Cholangitis Depends on Disease Presentation

Background: Multiple large colonoscopy screening trials in North America and Europe have shown 25-30% overall prevalence of adenomatous polyps and 3-10% prevalence of advanced neoplasia [AN= adenoma≥1cm, presence of villous histology, high grade dysplasia or cancer] in individuals ≥50 years. Corresponding prospective data in an average-risk Middle Eastern population has not been reported. Aims: To determine the prevalence of AN at screening colonoscopy in a prospective Lebanese population, and to develop a risk prediction rule based on AN predictor risk factors. Methods: Nine-hundred eighty average-risk individuals were prospectively enrolled at time of screening colonoscopy. Comprehensive data collection included demographics, diet details, medications, tobacco and alcohol use, risk factors and pathology findings. Multivariate binary logistic regression was used to determine predictors of AN, and the model coefficients were used to calculate %Risk of (AN) in nomogram format. Results: The adenoma detection rate was 36.6%. AN was identified in 50 patients (5.1%) including 8 cancers (0.8%). Multivariate predictors of AN were age [Odds Ratio (95% confidence interval)= 1.036(1.00-1.07); p=0.048], increased body habitus category [overweight : 2.21 (0.98-5.00); obese ( ≥30 kg/m2): 3.54(1.48-8.50); p=0.018] relative to normal (≤25 kg/m2) BMI, tobacco [,40 pack-years: 2.01(1.01-4.01); ≥40 pack-years: 3.96(1.86-8.42); p=0.002], and daily red meat consumption [2.02(0.92-4.42)]. Nomograms of the predicted, incremental AN risk with daily red meat and tobacco use categories are shown in terms of age separately for normal, overweight and obese individuals [Figure]. Conclusions: Prevalence of adenomatous polyps and advanced neoplasia in an average-risk Lebanese population are similar to those reported from other parts of the world. Increasing age, cumulative heavy tobacco use, and body habitus are important risk factors for advanced neoplasia, with obesity being a particularly powerful predictor. A targeted approach to screening those at higher risk by colonoscopy may prove highly cost-effective in the prevention of colorectal cancer.

Prevalence of adenomas and sessile serrated adenomas in Chinese compared with Caucasians

Colonic adenomas and sessile serrated adenomas (SSA) are the most common premalignant polyps identified at colonoscopy. This study compares the prevalence of neoplastic polyps in Chinese and Caucasians in a general gastroenterology outpatient practice in Australia. This study included consecutive unselected colonoscopies performed for standard clinical indications by a single endoscopist (JMH). All polyps detected were measured, resected, and sent for histopathology. The prevalence of adenomas, advanced adenomas, SSA, and cancer in the Chinese and Caucasian cohorts were compared. Advanced adenomas were defined as adenomas > 10 mm, villous histology, or high-grade dysplasia. The study included 346 Chinese and 654 Caucasians. There was no significant difference in the baseline characteristics including age, gender, and indications of colonoscopy, although Chinese were more likely to present with rectal bleeding (22.8% vs 15.9%, P = 0.01). The prevalence of adenomatous polyps was similar in both Caucasians (34.3%) and Chinese (35.3%). However, advanced adenomas were more significantly common in Caucasians (11.3%) compared with Chinese (4.6%) (P < 0.001). SSA was rare in Chinese (2%) but present more frequently in Caucasians (7%) (P = 0.001). Multivariate analysis showed that Caucasian ethnicity (odds ratio 2.4, 95% confidence interval 1.6-3.6) and the presence of SSA (odds ratio 4.4, 95% confidence interval 2.3-8.6) were independent predictors for the detection of an advanced adenoma. The prevalence of significant colorectal lesions, including advanced adenomas, large adenomas, and SSA, were lower in Chinese compared with Caucasians. These findings may influence the guidelines for colonic cancer screening in Chinese populations.

APC and KRAS mutations in distal colorectal polyps are related to smoking habits in men: results of a cross-sectional study

The purpose of this study was (a) to evaluate the association between cigarette smoking and the prevalence of distal colorectal polyps and adenocarcinoma and (b) to analyse genetic alterations representing different molecular pathways of the colorectal carcinogenesis. A total of 623 asymptomatic male (mean age: 53 years; 50-65) car factory workers were included. Information on smoking habits and other lifestyle factors were collected followed by a 60 cm colonoscopy. APC and KRAS mutations and microsatellite status were determined in colorectal lesions (colorectal carcinoma (CRC), hyperplastic (HP) and adenomatous polyps (AP)). Data were analysed using unconditional multiple logistic regression models. Smokers had a higher prevalence of AP (OR 2.1; 95% CI 1.2-3.6; p<0.05) and HP (OR 5.4; 95% CI 2.6- 11.1; p<0.05). No differences in CRC were observed. There was a dose-response relationship with the number of cigarettes smoked. The risk of developing AP or HP decreased after smoking cessation, even among heavy smokers (≥20 packs/year). KRAS mutations were more prevalent among smokers AP (OR 5.6; 95% CI 1.6-20.4; p=0.007). There was a trend of positive association with APC mutations (OR 3.5; 95% CI 0.9-4.4; p=0.096). APC and KRAS mutations were found in 36% and 61% of the HP of smokers, but were absent in non-smokers (p=0.89 and 0.78, respectively). There were no differences in MSI between smokers and non-smokers. Cigarette smoking is associated with a higher risk of developing both HP and AP and a higher prevalence of mutations in APC and KRAS.

A Previous Cholecystectomy Increases the Risk of Developing Advanced Adenomas of the Colon

There is limited data assessing the relationship between cholecystectomy and colorectal adenomatous polyps (AP). Our aim was to determine if cholecystectomy was associated with an increased prevalence of advanced AP in male veterans. The relationship of whether prior cholecystectomy modified the natural history of AP was investigated in a retrospective study. The patients were divided into two groups: 1) those with AP and a history of cholecystectomy, and 2) those with AP, but without a history of cholecystectomy. Factors in each group associated with advanced AP were examined by univariate analysis (UA) and stepwise logistic regression analysis to determine independent predictors of aggressive clinical characteristics of polyps. Statistical significance was determined at a P < or = 0.05. We identified a total of 1234 patients with AP (cases = 127, controls = 1107). The mean age of patients was 64.1 +/- 1.9 (standard deviation) years. By UA, those with a prior cholecystectomy had a greater mean number of AP (4.2 vs. 3.5; P = 0.04) and more advanced polyps (P = 0.037) than those without a cholecystectomy. By logistic regression, prior cholecystectomy was associated with more advanced AP (OR = 1.5 [1.0-2.2]; P = 0.04). Patients who had a cholecystectomy were 51% more likely to have advanced AP. There appeared to be a trend towards increased time from cholecystectomy being associated with advanced polyps (9.69 years vs. 8.99 years, P = 0.056). A prior cholecystectomy was independently associated with an increased risk of developing advanced AP. Also, there appeared to be a trend toward a greater prevalence of advanced lesions as postcholecystectomy time increased.

Prevalence of Adenomas and Colorectal Cancer in Average Risk Individuals: A Systematic Review and Meta-analysis

There is an extensive yet inconsistent body of literature reporting on the prevalence of adenomatous polyps (adenomas) and colorectal cancer among average risk individuals. The objectives of our study were to determine the pooled prevalence of adenomas and colorectal cancer, as well as nonadvanced and advanced adenomas, among average risk North Americans. Articles were obtained by searching electronic databases (MEDLINE: 1950 through March 2008 and EMBASE: 1980 through March 2008), bibliographies, major journals, and conference proceedings, with no language restrictions. Two reviewers independently selected cross-sectional studies reporting adenoma and colorectal cancer prevalence rates in average risk individuals and assessed studies for inclusion and quality, and extracted the data for analysis. Pooled adenoma and colorectal cancer prevalence rates were estimated using fixed and random effects models. Stratification and metaregression was used to assess heterogeneity. Based on 18 included studies, the pooled prevalence of adenomas, colorectal cancer, nonadvanced adenomas, and advanced adenomas was 30.2%, 0.3%, 17.7%, and 5.7%, respectively. Heterogeneity was observed in the pooled prevalence rates for overall adenomas, advanced adenomas, and colorectal cancer and was explained by the mean age (> or = 65 years vs < 65 years) with older cohorts reporting higher prevalence rates. None of the study quality indicators was found to be significant predictors of heterogeneity. The high prevalence of advanced adenomas and colorectal cancer, especially among older screen-eligible individuals, provides impetus for expanding colorectal cancer screening programs. Furthermore, the pooled prevalence estimates can be used as quality indicators for established programs.

Obesity Is Associated with an Increased Prevalence of Advanced Adenomatous Colon Polyps in a Male Veteran Population

Obesity has been associated with an increased risk for colonic adenomatous polyps (APs) and colorectal cancers, but the influence of obesity on the development of advanced APs is not clear. The purpose of this study is to determine the influence of obesity on the prevalence of advanced APs in a male veteran population. We performed a retrospective study of patients (n = 2,903) with histologically confirmed APs on an index colonoscopy. APs were evaluated for advanced features (size > or = 1 cm in diameter and/or a villous component and/or high grade dysplasia). Patients were categorized as: normal weight (BMI > 18.5 and < 25), overweight (BMI > or = 25 and < 30), and obese (BMI > or = 30). An association between clinical factors and advanced APs was sought by Kruskal-Wallis test and Pearson Chi-square. Multiple logistic regression analysis was used to determine independent predictors for advanced APs. We identified 2,903 male patients with APs (mean age 64 + 1.1(SE) years; 770 (27%) normal weight, 1,029 (35%) overweight, 1,104 (38%) obese. By univariate analysis, obese patients had a greater prevalence of advanced APs than the overweight and normal weight patients (28 vs. 23 vs. 24%, p = 0.025). Multiple logistic regression analysis confirmed the association of obesity and advanced APs (OR = 1.01, CI = 1-1.02, p = 0.04). For every one-unit increase in BMI above 30, there was a corresponding 1% increase in the frequency of finding advanced APs. Obesity in male veteran patients is associated with the finding of advanced APs on colonoscopy. We speculate that obesity may increase the risk for CRC by promoting the development of advanced APs.