Personal History Of Adenomas Research Articles

Gastrointestinal Cancer

Background and Aim: Colonoscopic surveillance is undertaken at regular intervals (typically 3 or 5 years) to reduce the incidence of colorectal cancer (CRC) in people with an elevated risk (personal or family history of neoplasia). Pathology findings at index and each surveillance colonoscopy determine recall intervals. Due to coronavirus disease 2019, hospital services around the world have been limited, resulting in some surveillance colonoscopies being delayed beyond the recommended time frames. Previous studies suggest that delays to colonoscopy might increase the incidence of advanced neoplasia (advanced adenoma/CRC). However, it is possible that this risk could be reduced by ensuring that individuals are maintained in a CRC screening program with an immunochemical fecal occult blood test (FIT) in the interval between surveillance colonoscopies. Our aim was to determine whether risk of advanced neoplasia increases if surveillance colonoscopy is delayed in people with elevated CRC risk who perform and have a negative FIT result in the interval between colonoscopies. Methods: We performed a retrospective cohort study using data from the Southern Cooperative Program for the Prevention of Colorectal Cancer on people at elevated risk because of family history or personal history of adenoma or CRC. People with at least two consecutive colonoscopies of a 3- or 5-year surveillance interval and who had at least one negative interval FIT result were included in the study. They were stratified based on a previous colonoscopy finding of advanced adenoma, non-advanced adenoma, or no neoplasia. People with early colonoscopies (3 months before the recommended due date), poor bowel preparation, previous CRC, or hereditary CRC syndromes were excluded from the study. Colonoscopy was defined as 'delayed' if it did not occur within 6 months after the recommended recall interval and was further subdivided into delays of 6-12, 12-24, and >24 months. The incidence of advanced neoplasia was calculated for all groups. The relative risk (RR) and 95% confidence intervals estimated from a robust multivariable modified Poisson regression were used to assess the association between surveillance colonoscopy delay and risk of advanced neoplasia. Results: A total of 1748 public hospital surveillance colonoscopies (in 1516 participants) were included in the analysis. More than half of the colonoscopies (56.86%, 994/1748) were delayed by at least 6 months because of system and/or patient factors. In people with delayed colonoscopies, the incidence of advanced neoplasia was higher in those with previous advanced adenoma (16.72%, 48/287) and previous non-advanced adenoma (15.23%, 37/243) compared with those with no neoplasia (6.25%, 29/464) (P < 0.001). However, relative to on-time colonoscopy, delay of surveillance colonoscopy was not associated with an increased risk of advanced neoplasia for people who had at least one negative interval FIT result, regardless of previous colonoscopy finding (previous advanced adenoma: RR, 1.01;95% CI, 0.70-1.46;non-advanced adenoma: RR, 1.41;95% CI, 0.85-2.33;and no neoplasia: RR, 0.96;95% CI, 0.55-1.66) (Table 1). Conclusion: In an elevated-risk cohort undergoing FIT screening between surveillance colonoscopies, delays to colonoscopy did not increase risk of advanced neoplasia. These results suggest that surveillance colonoscopy could be safely extended in people at elevated CRC risk by participating in FIT testing between colonoscopies within a surveillance program.

Abstract 477: Elevated EVL methylation level in the normal colon mucosa is a potential risk biomarker for developing metachronous polyps

Abstract The purpose of this study is to evaluate the use of molecular markers for more accurately predicting the individual risk of metachronous polyps or cancer during colonoscopic surveillance. Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related death in the United States. The risk of CRC varies among people; individuals who develop adenomas are at heightened risk of forming metachronous adenomas and interval cancer, compared to those without a personal history of adenoma or CRC. Yet, even in these high risk individuals, only 25-30% will develop subsequent adenomas. To date, few studies have evaluated the use of molecular markers for predicting the risk of metachronous lesions. We have demonstrated that aberrantly methylated mir342/EVL is present at a higher frequency in the normal colon of people with CRC compared to people with no colon cancer or polyps, suggesting it may indicate a field cancerization process. Further, we developed an ultra-sensitive quantitative Methylation-specific ddPCR (MS-ddPCR) assay to accurately determine the level of rare EVL methylation in the normal colon mucosa. To investigate the correlation of EVL methylation in normal mucosa and the risk of developing polyps during the follow-up colonoscopy, we conducted a retrospective cohort study (N=136 subjects) and EVL methylation status was determined in normal colon mucosa samples from these subjects. Among them, 71 subjects had polyps detected within 12 years of the index colonoscopy, and 11 subjects were polyp-free at all subsequent colonoscopic exams done within 8-16 years of the index colonoscopy (54 subjects did not meet the criteria for follow up, so were excluded from the following analysis). Applying the standard Inverse Probability Weighted Logistic Regression (IPWLR) model, we found that higher level of EVL methylation in the normal colon mucosa at the time of the index colonoscopy (which was when the tissue sample was collected) indicated an increased risk of having polyps detected within 12 years, compared to subjects with no polyps detected by colonoscopy done within 8-16 years (Odds Ratio (95% CI) = 4.35 (1.14, 16.60); p-value = 0.0317). Our results suggest that EVL methylation level in the normal colon mucosa can be used as a risk biomarker for metachronous adenomas. Citation Format: Ming Yu, Ting Wang, Kelly T. Carter, Kelsey Baker, Mary W. Redman, Kathy Vickers, Lynda Ann Dzubinski, Robert E. Schoen, William M. Grady. Elevated EVL methylation level in the normal colon mucosa is a potential risk biomarker for developing metachronous polyps [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 477.

Factors predicting the colorectal adenoma detection rate in colonoscopic screening of a Chinese population: A prospective study.

Colorectal cancer has high incidence and mortality. Early diagnosis could increase patient survival, but early diagnosis has been poor in China for the past decades. The purpose of this study is to assess the polyp detection rate (PDR) and adenoma detection rate (ADR) by colonoscopy in a Chinese population, and to determine the risk factors for adenoma.This prospective study at Sichuan Provincial People's Hospital evaluated patients who underwent colonoscopy in September 2017 to February 2018. Basic information, exact insertion and withdrawal times, PDR, and ADR were assessed. Risk factors for colorectal adenoma in the adenoma-positive and adenoma-negative groups (based on pathology) were assessed by multivariable logistic regression analysis.A total of 1058 procedures with 767 polyps were analyzed. The overall PDR and ADR were 36.96% (391/1058) and 24.67% (261/1058), respectively. Occurrence of adenoma was associated with age, gender, body mass index (BMI), family history of colon cancer, personal history of adenoma, diabetes mellitus, and tobacco use. There was a significant association between withdrawal time and ADR (P < .001). In the multivariable analysis, age (OR = 1.041, 95%CI 1.028–1.055; P < .001), insertion time (OR = 0.999, 95%CI 0.998–1.000; P = .009), withdrawal time (OR = 1.009, 95%CI 1.007–1.011; P < .001), personal history of adenoma (OR = 2.572, 95%CI 1.115–5.932; P = .027), and diabetes mellitus (OR = 2.221, 95%CI 1.084–4.549; P = .029) were risk factors for colorectal adenoma detection.In a Chinese population, ADR increases with age, withdrawal time, a personal history of adenoma, and diabetes. Age, insertion and withdrawal times, and a personal history of adenoma may independently predict colorectal adenoma detection.

Influence of Genetic Polymorphisms in Prostaglandin E2 Pathway (COX-2/HPGD/SLCO2A1/ABCC4) on the Risk for Colorectal Adenoma Development and Recurrence after Polypectomy

Objectives:Deregulation of prostaglandin E2 (PGE2) levels reported in colorectal carcinogenesis contributes to key steps of cancer development. Our aim was to evaluate the influence of the genetic variability in COX-2/HPGD/SLCO2A1/ABCC4 PGE2 pathway genes on the development and recurrence of colorectal adenomas.Methods:A case-control study was conducted gathering 480 unscreened individuals and 195 patients with personal history of adenomas. A total of 43 tagSNPs were characterized using the Sequenom platform or real-time PCR.Results:Ten tagSNPs were identified as susceptibility biomarkers for the development of adenomas. The top three most meaningful tagSNPs include the rs689466 in COX-2 (odds ratio (OR)=3.23; 95% confidence interval (CI): 1.52–6.86), rs6439448 in SLCO2A1 (OR=0.38; 95% CI: 0.22–0.65) and rs1751051 in ABCC4 genes (OR=2.75; 95% CI: 1.58–4.80). The best four-locus gene–gene interaction model included the rs1346271, rs1863642 and rs12500316 single nucleotide polymorphisms in HPGD and rs1678405 in ABCC4 genes and was associated with a 13-fold increased susceptibility (95% CI: 3.84–46.3, P<0.0001, cross-validation (CV) accuracy: 0.78 and CV consistency: 8/10). Interesting, in low-risk patients the ABCC4 rs9524821AA genotype was associated not only with a higher hazard ratio (HR=2.93; 95% CI: 1.07–8.03), but half of these patients had adenoma recurrence at 60 months, considerably higher than the 21% noticed in low-risk patients.Conclusions:Genetic polymorphisms in COX-2/PGE2 pathway appear to contribute to the development of colorectal adenomas and influence the interval time to adenomas recurrence. The definition of risk models through the inclusion of genetic biomarkers might improve the adherence and optimization of current screening and surveillance guidelines for colorectal cancer prevention.

Screening for Colorectal Cancer Is Associated With Lower Disease Stage: A Population-Based Study.

Screening for colorectal cancer (CRC) using fecal occult blood tests (FOBT) is associated with reduced CRC incidence and mortality. Population-based FOBT screening has led to identification of CRCs at earlier stages and longer patient survival times. We investigated the stage distribution of CRCs detected by colonoscopy in a large outpatient cohort. We performed a retrospective analysis of colonoscopies performed on 524,954 outpatients (age, ≥55 y) in Germany from January 2006 through December 2009. Patients with chronic inflammatory bowel diseases, and those with a personal history of adenoma or CRC, were excluded. Colonoscopy findings were categorized on the basis of the most advanced lesion found; histologic samples were obtained from all patients with suspected cancer and analyzed. Cancers were staged based on Union Internationale Contre le Cancer criteria. We analyzed absolute and relative frequencies of CRCs identified and tumor stages for patients who underwent colonoscopy for screening, evaluation of a positive FOBT, and evaluation of symptoms. Of the 6065 CRCs identified, 1750 were found in the screening group, 1075 in subjects with positive FOBT, and 3240 in patients with symptoms. Stage I CRC was detected more frequently in subjects who received screening colonoscopies (41.15%) or in those with positive FOBT (39.10%), than in individuals with symptoms (24.42%; P < .001). In contrast, the detection rates of stage IV CRC were 10.67%, 10.76%, and 18.64%, respectively (P < .001). We observed a shift toward lower T stages in the screening and FOBT work-up groups compared with the group with symptoms. Compared with subjects with symptoms, the odds of diagnosing CRC at an advanced stage were significantly lower in the screening group (odds ratio, 0.533; 95% confidence interval, 0.451-0.631) and the FOBT work-up group (odds ratio, 0.570; 95% confidence interval, 0.469-0.694). In this large population-based study, CRC detected by colonoscopies performed for screening and evaluation of positive FOBTs had a lower stage than those diagnosed by colonoscopies in symptomatic patients. These findings support the value of screening colonoscopy to reduce the burden of CRC.

Adenoma Detection Rate May Be Higher in Whites With a Personal History of Adenomas

Adenoma Detection Rate May Be Higher in Whites With a Personal History of Adenomas

Regular colonoscopy could prevent 40% of colorectal cancers

CancerVolume 120, Issue 2 p. 156-157 CancerScopeFree Access Regular colonoscopy could prevent 40% of colorectal cancers Carrie Printz, Carrie PrintzSearch for more papers by this author Carrie Printz, Carrie PrintzSearch for more papers by this author First published: 07 January 2014 https://doi.org/10.1002/cncr.28541AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Researchers at the Harvard School of Public Health (HSPH) in Boston, Massachusetts, found that 40% of all colorectal cancers could be prevented if people underwent regular colonoscopy screening. Their results, from a large long-term study, support current guidelines that recommend people of average risk for the disease undergo colonoscopy every 10 years.1 Co-senior author Shuji Ogino, MD, PhD, an associate professor in the department of epidemiology at HSPH, says that previously insufficient evidence existed regarding how much colonoscopy reduces colorectal cancer incidence and mortality, particularly among patients in whom the cancer originates in the proximal part of the colon. Evidence from this study demonstrates that colonoscopy is effective in preventing cancer in both the distal and proximal regions of the colorectum, whereas sigmoidoscopy alone is insufficient for preventing proximal disease, he adds. Dr. Ogino and his colleagues reviewed data from 88,902 participants in both the Nurses' Health Study and Health Professionals Follow-Up Study. Participants completed questionnaires every 2 years between 1998 and 2008, and researchers documented 1815 cases of colorectal cancer and 474 deaths from the disease. They found that colonoscopy and sigmoidoscopy were linked to a decreased risk of either developing colorectal cancer or dying of it. Although colonoscopy was found to lessen the risk of cancers originating in the proximal colon, it was more effective against those arising in the distal colon. The procedure's decreased effectiveness in reducing the risk of tumors developing in the proximal colon may be attributed to molecular and biological differences between the 2 cancers, researchers say. Additional findings include: If all study participants had undergone colonoscopies, an estimated 40% of colorectal cancers, would have been prevented. Individuals who undergo colonoscopies and are cleared of any problems have a significantly reduced risk of colorectal cancer for up to 15 years after the procedure; however, those with a personal history of adenoma or a family history of colorectal cancer should be screened more often. Colorectal cancers diagnosed within 5 years of a colonoscopy had different molecular characteristics compared with those diagnosed more than 5 years after the procedure. They also may be harder to detect and fully remove. Reference 1 Nishihara R, Wu K, Lochhead P, et al. Long-term colorectal-cancer incidence and mortality after lower endoscopy. N Engl J Med. 2013; 369: 1095– 1105. CrossrefCASPubMedWeb of Science®Google Scholar Volume120, Issue215 January 2014Pages 156-157 This article also appears in:CancerScope Archive 2014-2019 ReferencesRelatedInformation

Early colon cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

Early colon cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

FADS genotype affects change in fatty acid levels after a Mediterranean dietary intervention

A Mediterranean diet increases intake of n‐3 and n‐9 fatty acids and lowers intake of n‐6 fatty acids. Limiting n‐6 fatty acid levels is expected to decrease levels of pro‐inflammatory eicosanoids such as prostaglandin E2 (PGE2) that increase colon cancer risk. This study evaluated whether polymorphisms in fatty acid desaturases (FADS1 and FADS2) genes may identify subgroups that have a greater response to dietary changes. A total of 107 individuals with a personal history of adenomas or colon cancer were randomized to either a Mediterranean diet or a Healthy diet. Fatty acids were measured in both serum and colonic mucosa at baseline and at 6 months. Each individual was genotyped for 4 SNPs in the FADS1/FADS2 cluster. Genetic variation in the FADS cluster was strongly associated with baseline serum arachidonic acid (p&lt;0.0001) but less evidence was present for serum and colonic mucosa n3 fatty acids. Minor allele carriers had lower 20:4, n6 levels at baseline than major allele carriers. Both diets led to slightly but not significantly lower 20:4, n6 levels at 6 months. The Mediterranean diet intervention increased long chain n3 fatty acids in the colonic mucosa. There was a significant interaction of diet and FADS genotype on changes in fatty acid levels after intervention indicating that a Mediterranean intervention may have a relatively larger impact in specific subgroups.

Short- and long-term risk of colorectal adenoma recurrence among whites and blacks

It is unclear whether the higher burden from colorectal cancer among blacks is due to an increased biological susceptibility. To determine whether non-Hispanic blacks (blacks) have a higher risk of adenoma recurrence than non-Hispanic whites (whites) after removal of colorectal adenoma. Secondary analysis of the Polyp Prevention Trial (PPT) data. United States. Patients were 1668 self-identified whites and 153 blacks who completed the 4-year trial. Of these, 688 whites and 55 blacks enrolled in a posttrial, passive Polyp Prevention Trial Continued Follow-up Study (PPT-CFS) and underwent another colonoscopy. Recurrence and location of the adenoma and advanced adenoma by race-ethnicity during PPT and cumulative recurrence over a mean follow-up of 8.3 years (range, 4.9-12.4 years) among PPT-CFS enrollees. Blacks had similar risk of recurrence of adenoma (39.2% vs 39.4%; incidence risk ratio [RR] = .98; 95% CI, .80-1.20) and advanced adenoma (8.5% vs 6.4%; RR = 1.18; 95% CI, .68-2.05) as whites at the end of PPT. Recurrence risk did not differ by colon subsite. Among PPT-CFS enrollees, the cumulative recurrence rate over a maximal follow-up period of 12 years was similar for blacks and whites for adenoma (67.3% vs 67.0%; RR = 1.01; 95% CI, .84-1.21) and advanced adenoma (14.5% vs 16.9%; RR = 1.03; 95% CI, .60-1.79). There were few blacks in the long-term follow-up study. Adenoma and advanced adenoma recurrence did not differ by race. Our study does not support more frequent surveillance colonoscopies for blacks with a personal history of adenoma as an intervention to reduce colorectal cancer disparity.

Pyogenic Granuloma of Gastrointestinal Tract: A Large Case Series and Review of Literature

Purpose: To report all available cases of PG of intestinal tract, diagnosed at our hospital in the last 10 years and to review previously reported cases in the literature. Methods: A retrospective review of the pathology database was performed on all gastrointestinal biopsies in the last 10 years using diagnostic and pathology codes searching for PG of the gastrointestinal tract. Results: A total of 23 cases of pathologically proven PG were diagnosed over a 10 year period. The median age of patients was 64 (±9) years with 47.8% men and 52.2 % women. The most common location of the PG was the colon - 19 (82.6%) cases (14 cases in sigmoid colon, 3 cases in transverse colon and 1 case in splenic flexure) followed by esophagus - 4 cases (17.4%) and rectum - 1 case (4.3%). PG presented as a polyp in 16 patients (69.6%) and as an erythematous inflamed edematous mucosa in 6 patients (26%). The polyp was Sessile in most cases - 13 patients (81.3%) and pedunculated in the rest - 3 patients (18.7%). The size of polyp was <1 cm in 8 patients and >1 cm in the rest. Endoscopically, most lesions appeared as inflammatory pseudopolyps without features suggestive of adenoma. The most common indication for endoscopy was screening/surveillance colonoscopy (82.6% cases) with a family history of colon cancer or polyp in a first degree relative in 5 patients, a personal history of adenoma in the past in 4 cases and colorectal cancer in 3 cases. Other indications for endoscopy were melena in 4 cases (17.4%), iron deficiency anemia in 2 cases (8.7%) and acute flare of ulcerative colitis in 1 patient (4.3%). Conclusion: PG of gastrointestinal tract is rare. To date, only about 15-20 cases have been reported in the literature mainly from Japan and Korea. To our knowledge this is the largest case series (23 cases) of this rare pathological lesion of gastrointestinal tract. In our series, most cases of PG were incidental findings in an asymptomatic patient who had an endoscopy done for an unrelated reason, unlike previously reported cases which were mostly associated with gastrointestinal bleeding. In summary, PG is a rare pathological lesion in GI tract excluding the oral cavity and can present in various ways ranging from an asymptomatic polyp to a life threatening GI bleeding.

Su1043 Prognostic Significance of Socio-Economic Deprivation in Upper Gastrointestinal Cancer

Background: Blacks suffer a disproportionately higher incidence of and mortality from colorectal cancer in the United States. It is unclear if this public health problem is due to an increased biological susceptibility. No prospective study has evaluated differences in postpolypectomy recurrence risk by race. Aim: To examine the prevalence, recurrence and the location of colorectal neoplasia by race during a four-year follow-up in the Polyp Prevention Trial (PPT). Methods: The PPT was a 4-year, multicenter, randomized controlled trial which evaluated the effect of a low fat, high fiber, fruits and vegetable diet on the risk of colorectal adenoma recurrence. A total of 1,821 participants, which included 1,668 (91.6%) whites and 153 (8.4%) blacks, had information on location of colorectal adenoma at baseline and underwent end-of-trial colonoscopy 4 years later. We used Poisson regression models to evaluate the association between race and advanced adenoma (defined as an adenoma that is 1 cm or more in size, or with villous component or high grade dysplasia) at baseline and recurrent adenoma and advanced adenoma at 4 years. Results: Black and white participants did not differ on mean age (60.8 versus 61.3 years; P value = 0.53) or sex (66.7% versus 64.0% male; P value = 0.52). At baseline, blacks had higher prevalence of any advanced adenoma compared to whites (44.4% versus 37.0%; P value = 0.07) and proximal advanced adenoma (14.4% versus 8.8%; P value = 0.02); but not distal advanced adenoma (32.0% versus 29.9%, P value = 0.58). At the year 4 examination, 717 (39.4%) had adenoma recurrence and 120 (6.6%) had advanced adenoma recurrence. Blacks were as likely as whites to have any adenoma and advanced adenoma recurrence after adjusting for age, sex, body mass index, use of non steroidal anti-inflammatory drugs, smoking and family history of colorectal cancer (Table). There was no difference in adenoma recurrence by location. Conclusions: Despite higher prevalence of advanced adenoma at baseline, blacks have similar colorectal neoplasia recurrence risk as whites. Our study does not provide any evidence to support more frequent surveillance for blacks with personal history of adenoma as an intervention to reduce colorectal cancer disparity. The risk of adenoma and advanced adenoma recurrence by race

Colorectal cancer screening in patients at moderately increased risk due to family history

Patients with a positive family history have an increased risk of colorectal cancer (CRC) and, in many countries, more intensive screening regimens, sometimes involving the use of colonoscopy as opposed to sigmoidoscopy or fecal occult blood testing, are recommended. This review discusses current screening guidelines in the United States and other countries, data on the magnitude of CRC risk in the presence of a family history and the efficacy of recommended screening programs, as well as ancillary issues such as compliance, cost-effectiveness and accuracy of family history ascertainment. We focus on the relatively common "sporadic" family histories of CRC, which typically imparts a mild to moderate elevation in the risk for CRC development in the proband. Defined familial syndromes associated with extremely high risks of CRC, such as hereditary non-polyposis colorectal syndrome or familial adenomatous polyposis, require specialized management approaches and are beyond the scope of this article. We will also not discuss colonoscopic surveillance in patients with a personal history of adenomas or CRC.

The community uptake of an online CRC risk assessment and its utility to assess for a potential hereditary colon cancer syndrome

Purpose The identification of individuals with Hereditary Non Polyposis Colorectal Cancer (HNPCC) in the population is suboptimal. Causes include lack of physician recognition or failure to take an accurate family history. While colorectal cancer (CRC) in HNPCC is preventable by annual colonoscopy it is underutilized in part by lack of physician recommendation or poor understanding of personal risk of disease. We developed an online CRC risk assessment (http://www.clevelandclinic.org/score) incorporating family and personal history of adenomas and CRC which generated a pedigree, risk category and screening recommendations based on ACG guidelines. Modifiable lifestyle factors were also assessed and personalized recommendations were provided to minimize neoplasia due to those factors. We assessed the feasibility and online uptake of this tool and determined the proportion of high risk individuals who meet criteria suspicious for HNPCC. Methods The assessment included questions on demographics, use of previous CRC screening, and family and personal history of adenomas and CRC in 3 generations. Height, weight, age > or < 50, race, smoking exposure, physical activity, and dietary habits assessed. Risk categories included average, low, medium, and high.

Prevention by Aspirin of Colorectal Adenoma Recurrence: Some Advances and Latest Results of the APACC Trial

In a randomized controlled trial (RCT), 272 patients were assigned to lysine acetylsalicylate 160 mg/day (n = 73) or 300 mg/day (n = 67) or placebo (n = 132). The primary end points were adenoma recurrence and adenomatous polyp burden (APB) at year 1 or 4 (last colonoscopy) and at year 4. At last colonoscopy, APB tended to be lower under aspirin 160 mg or at either dose compared with placebo (P = 0.06 and 0.07, respectively). At year 4, 55 patients had received aspirin 160 mg/d, 47,300 mg/d, and 83 placebo. APB and proportions of patients with at least one recurrent adenoma were similar in both groups. A personal history of adenomas and an initial APB higher than 10 mm predicted recurrence. Among 219 adenomas from 136 patients, 128 adenomas (58%) from 59 patients strongly expressed COX-2 assessed by immunohistochemistry, mainly adenomas larger than 10 mm (84/129 vs 44/90; P = 0.02) and adenomas showing high-grade dysplasia (22/29 vs 104/188; P = 0.04). Deep stromal initial expression of COX-2 predicted recurrence (P = 0.04). Protection by aspirin was mainly observed in patients in whom COX-2 initial expression was low (RR: 0.59; 95% CI = 0.39–0.90; P = 0.02). Aspirin decreased adenoma recurrence significantly at 1 year, marginally at year 1 or 4, and not at year 4, possibly due to attrition but also to a differential effect according to polyp natural history. In a recent patient-level meta-analysis including the four published RCTs, aspirin significantly decreased adenoma risk by 17% and risk of advanced lesions by 28%.

Diagnostic Accuracy of Computed Tomographic Colonography for the Detection of Advanced Neoplasia in Individuals at Increased Risk of Colorectal Cancer

Computed tomographic (CT) colonography has been recognized as an alternative for colorectal cancer (CRC) screening in average-risk individuals, but less information is available on its performance in individuals at increased risk of CRC. To assess the accuracy of CT colonography in detecting advanced colorectal neoplasia in asymptomatic individuals at increased risk of CRC using unblinded colonoscopy as the reference standard. This was a multicenter, cross-sectional study. Individuals at increased risk of CRC due to either family history of advanced neoplasia in first-degree relatives, personal history of colorectal adenomas, or positive results from fecal occult blood tests (FOBTs) were recruited in 11 Italian centers and 1 Belgian center between December 2004 and May 2007. Each participant underwent CT colonography followed by colonoscopy on the same day. Sensitivity and specificity of CT colonography in detecting individuals with advanced neoplasia (ie, advanced adenoma or CRC) 6 mm or larger. Of 1103 participants, 937 were included in the final analysis: 373 cases in the family-history group, 343 in the group with personal history of adenomas, and 221 in the FOBT-positive group. Overall, CT colonography identified 151 of 177 participants with advanced neoplasia 6 mm or larger (sensitivity, 85.3%; 95% confidence interval [CI], 79.0%-90.0%) and correctly classified results as negative for 667 of 760 participants without such lesions (specificity, 87.8%; 95% CI, 85.2%-90.0%). The positive and negative predictive values were 61.9% (95% CI, 55.4%-68.0%) and 96.3% (95% CI, 94.6%-97.5%), respectively; after group stratification, a significantly lower negative predictive value was found for the FOBT-positive group (84.9%; 95% CI, 76.2%-91.3%; P < .001). In a group of persons at increased risk for CRC, CT colonography compared with colonoscopy resulted in a negative predictive value of 96.3% overall. When limited to FOBT-positive persons, the negative predictive value was 84.9%.

CT Colonography in Patients at Elevated Risk for Colorectal Cancer

Computed tomographic (CT) colonography to screen for colorectal cancer has been studied primarily in average-risk populations. In this European study, 937 people at higher risk (family history of colorectal cancer, personal history of adenomas, or positive fecal occult blood testing [FOBT]) were recruited to undergo CT colonography followed by …

Abstract B135: A Mediterranean dietary intervention for reducing colon cancer risk

Abstract B135 Epidemiological and animal studies indicate that the major components of the traditional Cretan-Mediterranean diet have great promise for the prevention of colon cancer while improving overall health. We designed an exchange-list diet that would target 1) an increase in amount and variety of fruits and vegetables, 2) an increase in whole grains and 3) a decrease in n-6 fatty acids with increased n-3 and n-9 fatty acids. The exchange list approach provided flexibility in food choices for meeting nutrient goals. In this ongoing study we are recruiting study participants at increased risk for colon cancer. Subjects are being randomized to a modified Mediterranean diet or a Healthy People 2010 diet for 6 months, each of which involves intensive dietary counseling. Dietary intake data, blood samples and biopsies of normal colonic mucosa from flexible sigmoidoscopy are being collected and analyzed. Thus far 45 subjects have been enrolled with a mean age of 52 years, mean BMI of 28 kg/m2 and 67% were female. Two thirds of the subjects had a family history of colon cancer and the remainder had a personal history of adenomas. Dietary intakes of mono-unsaturated fats increased by about 70% and fruit and vegetables intakes doubled, but caloric intake did not change appreciably in the Mediterranean arm. This indicates that the exchange list diet was an effective tool. HPLC-MS-MS methods were developed to profile prostaglandins and leukotrienes in granulocytes and colonic mucosa using a single chromatographic run. Thus far granulocyte samples from 23 subjects have been analyzed there was a trend for decreases in several eicosanoids in samples from the Mediterranean arm while changes in the Healthy Eating arm were more variable. These preliminary data indicate that subjects can make large dietary changes and that this may impact on inflammation. Effects on biomarkers in the colonic mucosa are ongoing and will be important to evaluate the potential preventive effects of a Mediterranean type of diet. Supported by NIH grant 1RO1CA120381. Citation Information: Cancer Prev Res 2008;1(7 Suppl):B135.

The Detection of Flat and Depressed Colorectal Lesions: Which Endoscopic Imaging Approach?

The secondary prevention of colorectal cancer (CRC) assumes that early detection and resection of precursor lesions disrupts the adenoma– carcinoma sequence and halts progression to invasive neoplastic disease. The adenoma– carcinoma sequence has until now formed the rationale for endoscopic therapies directed at reducing the incidence of CRC. The fact that snare polypectomy of exophytic lesions fails to prevent progression to carcinoma in up to 24% of cases has prompted reevaluation of the prevalence and clinicopathologic significance of flat and depressed colorectal lesions in Western population cohorts. Such lesions, although well-described in the Japanese literature, have only recently been reported in Western population cohorts. Debate has continued regarding their prevalence, anatomic localization, histopathologic characteristics, and proposed imaging modality of choice. Within this perspective, we summarize the key data pertinent to recently described endoscopic diagnostic modalities and detail their clinical applicability both for the detection of flat neoplastic lesions occurring in the “sporadic” patient cohort, familial polyposis syndromes, and chronic ulcerative colitis.

Impact of Wide-Angle, High-Definition Endoscopy in the Diagnosis of Colorectal Neoplasia: A Randomized Controlled Trial

It is essential to optimize standard colonoscopy technique to be able to increase polyp detection. We sought to compare the performance of colonoscopy using a high-definition, wide-angle endoscope (HDE) versus a standard colonoscope (SC) for the detection of colorectal neoplasia. All consecutive consenting adult patients referred from primary care centers were included and randomly assigned at a 1:1 ratio to undergo HDE or SC. Times to reach and withdraw from the cecum were measured. Morphology, size, location, and pathologic diagnosis of each polyp were recorded. Sample size calculation resulted in a total of 682 patients needed. A total of 693 consecutive patients fulfilled all inclusion criteria (73 excluded owing to insufficient bowel preparation). Each arm included 310 patients with no baseline characteristic differences. Time to reach the cecum was slightly superior for SC (8.9 +/- 4.8 minutes vs 8.2 +/- 4.5 minutes; P = .055). Pathology examination was feasible in 418 lesions (272 adenomas, 109 hyperplastic polyps, and 37 inflammatory lesions). Both techniques detected a similar number and type of lesions, and there were no differences in the distribution along the colon, in the degree of dysplasia, or morphology of adenomas. The per-patient basis analyses demonstrated that there were no differences between the 2 arms of the study in the detection rates of polyps (SC, 0.84 +/- 1.59; HDE, 0.83 +/- 1.30), adenomas (0.45 +/- 1.07 vs 0.43 +/- 0.87), small adenomas (0.22 +/- 0.71 vs 0.28 +/- 0.78), flat adenomas (0.30 +/- 0.91 vs 0.21 +/- 0.63), or hyperplastic polyps (0.16 +/- 0.50 vs 0.18 +/- 0.54). HDE did not detect significantly more colorectal neoplasia than SC.