Risk Factors For Adenoma Research Articles

Is Colonoscopy Necessary Following an Episode of Diverticulitis in Patients Younger than 50 Years of Age?

Purpose: Diverticular disease is the 5th most costly gastrointestinal disease. Most common complications are bleeding and diverticulitis. 10-25% of patients (pts) with diverticulosis may develop diverticulitis. In 2005, incidence of diverticulitis was 150-180/100,000 adults. During 1980s it was advised that patients with diverticulitis undergo colonoscopy after an acute attack to evaluate the colon. Our aim is to study whether doing a colonoscopy after diverticulitis is essential or not. Methods: All pts (n=509), <50 yrs of age, with clinical and radiological diagnoses of diverticulitis at Montefiore Medical Center (MMC) were examined from 01/01/05 to 12/31/10. Clinical Looking Glass software was utilized to collect this patient group. A subset of 192 pts was identified who had either a colonoscopy or pathology report (colonoscopy or resection specimens) on record and were examined to determine if colonoscopy was useful in identifying an adenoma or adenocarcinoma after diverticulitis episodes. Results: Total pts (n) = 509; age = 40.5±6.5(sd) yrs (19-49yrs); gender = 48.5% female & 51.5% male; race = 15.9% Whites, 26.7% Afro-Americans, 23.0% Multi-racial, 3.0% Hispanics, 29% others,& 2.6% Asians; BMI = 31.9±7.6(sd) [14.3 - 63.2]; comorbidity in the sample included 8.3% diabetes mellitus; 23.6% HTN; 1% CKD III-V stages and 1.2% hypothyroid. Of the 192 pts, 85 had colonoscopy at MMC and 50 had pathology reports at MMC from colonoscopy specimens collected from ambulatory centers; 72 pts had surgical resection of colon. On the colonoscopy reports, 8 pts had polyps in the diverticulitis area, 16 pts had polyps in a non-diverticulitis area, & 3 pts had polyps in both areas. On pathology reports 13 pts had adenomas in the diverticulitis area and 17 pts had adenomas in a non-diverticulitis area. One pt had invasive adenocarcinoma in the diverticulitis area. In this group regression analysis determined that gender, Afro-American race, BMI and the above-identified comorbidities were not related to the number of diverticulitis episodes and its complications. This analysis identified age to be a significant factor for adenoma or cancer in the sample. For every 1-year increase in age (>19 years), the analysis determined a 12% increased risk for adenoma or cancer (p=0.006). Conclusion: 1. Increasing age is a significant risk factor for finding adenoma or cancer - 12% increased risk for every 1 yr increase in age (>19). 2. In this sample total adenoma detection rate is 15.6% and cancer detection rate is 0.52%. 3. Age, gender, Afro-American race and individual comorbidities were not related to developing recurrent diverticulitis or its complications. 4. There is no significant relation in increased risk of finding an adenoma in the area of diverticulitis.

Nephrogenic Adenoma in the Augmented Bladder

Nephrogenic adenoma is an uncommon, benign urothelial lesion. Risk factors for nephrogenic adenoma include trauma, chronic inflammation, immunosuppression and radiation. We characterized nephrogenic adenoma in the pediatric augmented bladder. We reviewed the records of patients diagnosed with nephrogenic adenoma from January 2000 to March 2010. Those with prior bladder augmentation were studied further. Data were retrospectively obtained on pathological characteristics, cystoscopic findings, recurrence patterns and presentation. Ten patients with ileal bladder augmentation and nephrogenic adenoma were identified. The underlying pathological condition was myelodysplasia in 7 patients, sacral agenesis in 2 and bladder exstrophy in 1. Concomitant procedures were a continent channel in 9 patients, ureteroneocystostomy in 5 and bladder neck reconstruction in 7. Mean time to the discovery of nephrogenic adenoma was 9.2 years. During that time a total of 221 surveillance cystoscopies were performed in patients with bladder augmentation. The diagnosis was made by surveillance cystoscopy in 7 cases, at surgery for bladder stone in 2 and by cystoscopy for urinary incontinence in 1. Nephrogenic adenoma was identified along the floor in 5 cases, near the channel entrance in 3 and adjacent to the enteric anastomosis in 2. Six patients returned for surveillance with recurrence identified in 2. The longest recurrence free interval was 27 months. Nephrogenic adenoma is not uncommon in the augmented bladder and it is often asymptomatic. The lesions tend to develop at sites that may be prone to chronic catheterization injury. Recurrent lesions are not unusual.

The value of age and medical history for predicting colorectal cancer and adenomas in people referred for colonoscopy

BackgroundColonoscopy is an invasive and costly procedure with a risk of serious complications. It would therefore be useful to prioritise colonoscopies by identifying people at higher risk of either cancer or premalignant adenomas. The aim of this study is to assess a model that identifies people with colorectal cancer, advanced, large and small adenomas.MethodsPatients seen by gastroenterologists and colorectal surgeons between April 2004 and December 2006 completed a validated, structured self-administered questionnaire prior to colonoscopy. Information was collected on symptoms, demographics and medical history. Multinomial logistic regression was used to simultaneously assess factors associated with findings on colonoscopy of cancer, advanced adenomas and adenomas sized 6 -9 mm, and ≤ 5 mm. The area under the curve of ROC curve was used to assess the incremental gain of adding demographic variables, medical history and symptoms (in that order) to a base model that included only age.ResultsSociodemographic variables, medical history and symptoms (from 8,204 patients) jointly provide good discrimination between colorectal cancer and no abnormality (AUC 0.83), but discriminate less well between adenomas and no abnormality (AUC advanced adenoma 0.70; other adenomas 0.67). Age is the dominant risk factor for cancer and adenomas of all sizes. Having a colonoscopy within the last 10 years confers protection for cancers and advanced adenomas.ConclusionsOur models provide guidance about which factors can assist in identifying people at higher risk of disease using easily elicited information. This would allow colonoscopy to be prioritised for those for whom it would be of most benefit.

The obesity gene and colorectal cancer risk: A population study in Northern Italy

Background Representing the second cause of cancer-related death after lung cancer in men and breast cancer in women, colorectal cancer (CRC) is a major health problem in Italy. Obesity is reckoned to favor CRC; however, the underlying mechanisms are unclear. Recently, a single nucleotide polymorphism (SNP) in the fat mass and obesity associated ( FTO) gene was found to be significantly associated with obesity. Aims To establish whether the FTO SNP rs9939609 may represent a risk factor for CRC and adenoma in the Italian population. Patients and methods 1,037 subjects were enrolled in the study and divided in 3 groups: CRC (341 pts., M/F = 197/144, mean age = 65.17 ± 11.16 years), colorectal adenoma (385 pts., M/F = 247/138, mean age = 62.49 ± 13.01 years), healthy controls (311 pts., M/F = 150/161, mean age = 57.31 ± 13.84 years). DNA was extracted from whole blood, and stored frozen for rs9939609 genotyping by real-time PCR. Results The frequency of the obesity-associated mutated A allele (AA+AT) on the FTO gene was 69.77% among controls, and 71.85% and 65.71% respectively among CRC and polyp patients. Compared to control subjects the AA+AT genotype had no significant effect on the risk for either CRC (OR = 1.106; CI 95% = 0.788–1.550; p = 0.561) or colorectal adenomas (OR = 0.830; CI 95% = 0.602–1.144; p = 0.255). We did not observe any association between the AA genotype and CRC/polyp localization and age at diagnosis. As measured in a patient subset, carriership of the risk alleles did not reflect in a significantly altered BMI. Conclusion The obesity-linked FTO variants do not play a significant role in modulating the colorectal cancer risk in the Italian population.

Risk factors for advanced adenomas amongst small and diminutive colorectal polyps: A prospective monocenter study

Background The management of colorectal polyps <10 mm in diameter is controversial. Our aim was to evaluate the rate and risk factors for advanced adenomas and high grade neoplasia amongst small (6–9 mm) and diminutive (1–5 mm) colorectal polyps. Methods Endoscopic and pathological reports of colonoscopies performed in our centre were collected prospectively. Advanced adenoma was defined by presence of a villous component and/or high grade dysplasia; high grade neoplasia by presence of high grade dysplasia and/or intramucosal carcinoma. Results 1468 patients were included (53.1% male, mean age 59.5 ± 14 years); 414 polyps <10 mm were detected, 9.9% advanced adenomas and 1.7% high grade neoplasia. Amongst small polyps, 25 (35.2%) were advanced adenomas, mainly due to villous features, and 3 (4.2%) were high grade neoplasia. Polyp size was associated with advanced adenomas (odds ratio = 8.47). Conclusion The rate of advanced adenomas amongst small polyps was 35%, mainly due to the presence of villous features. Polyp size was identified as a risk factor of advanced adenoma amongst polyps <10 mm. Given these results, we believe that polypectomy should be warranted for patients presenting with small polyps at computed tomography colonography.

Smoking and the Association of Advanced Colorectal Neoplasia in an Asymptomatic Average Risk Population: Analysis of Exposure and Anatomical Location in Men and Women

Identifying risk factors for advanced colorectal adenomas may aid in colorectal cancer (CRC) screening, especially in light of the American College of Gastroenterology's recent guidelines, emphasizing cancer prevention through identification and removal of advanced adenomas. Smoking is an important risk factor for advanced adenomas but there is little data regarding levels of exposure for genders. The aim of this study was to use an existing database to examine the genders separately with respect to exposure level and anatomic location of advanced adenomas. Our database was designed to study smoking in an asymptomatic, screening population. Data included demographics, family history of CRC, smoking exposure (pack-years and years smoked), alcohol, diabetes, medications, exercise and dietary history. We excluded patients with a first degree relative with CRC. Compared to non-smokers, female smokers had an increased risk for advanced adenomas with an exposure of 10-30 pack-years (adjusted odds ratio [AOR] = 4.11; 95% confidence interval [CI], 1.88-9.01) as well as for ≥30 pack-years (AOR = 2.54; 95% CI, 1.08-5.96) while men had an increased risk with smoking ≥30 pack-years (AOR = 3.10; 95% CI, 1.71-5.65). An increased association with smoking was observed for proximal advanced adenomas (AOR = 4.06; 95% CI, 1.62-10.19) and large hyperplastic polyps in women. Women smokers had an increased risk for advanced adenomas at a lower exposure level and had a greater risk for proximal lesions. These findings may have an impact on CRC screening for women.

Dietary Patterns and the Risk of Colorectal Adenomas: the Black Women's Health Study

Colorectal adenomas are benign lesions that may be precursors to colorectal cancer. No studies of African American women have investigated dietary patterns and the risk of developing colorectal adenomas. We examined data from the Black Women's Health Study to determine whether dietary patterns are associated with the risk of developing colorectal adenomas. This is a prospective cohort study of 59,000 participants followed biennially since 1995. During 155,414 person-years of follow-up from 1997 to 2007 among women who had had at least one screening colonoscopy, 620 incident cases of colorectal adenomas were identified. By using Cox regression models, we obtained incidence rate ratios (IRR) for colorectal adenoma in relation to quintiles of each of two dietary patterns, adjusting for other colorectal adenoma risk factors. Two dietary patterns, Western and prudent, were utilized to assess the association between dietary intake and adenoma risk. The highest quintile of prudent diet, relative to the lowest quintile, was significantly associated with 34% lower colorectal adenoma risk overall (IRR = 0.66; 95% CI, 0.50-0.88; P(trend) < 0.01). Higher scores on the Western pattern were associated with a higher risk of developing colorectal adenoma (IRR = 1.42; 95% CI, 1.09-1.85 for the highest quintile relative to the lowest; P(trend) = 0.01). Our findings suggest that African American women may be able to reduce their risk of developing colorectal adenomas by following a prudent dietary pattern and avoiding a more Western pattern. A dietary modification could have a strong impact in colorectal adenoma prevention in African American women.

Abstract 1925: Dietary patterns and the risk of colorectal adenomas: The Black Women's Health Study

Abstract Background: Colorectal adenomas are benign lesions that may be precursors to colorectal cancer. No studies of African American women have investigated dietary patterns and the risk of colorectal adenomas. Objective: We examined data from the Black Women's Health Study (BWHS) to determine whether dietary patterns are associated with the risk of colorectal adenomas. Methods: This is a prospective cohort study of 59,000 participants followed biennially since 1995. During 155,414 person-years of follow-up from 1997 to 2007 among women who had had at least one screening colonoscopy, 620 incident cases of colorectal adenomas were identified. Using Cox regression models, we obtained incident rate ratios (IRR) for colorectal adenoma in relation to quintiles of each of two dietary patterns, adjusting for other colorectal adenoma risk factors. Results: Two dietary patterns, Western and prudent, were utilized to assess the association between dietary intake and adenoma risk. The highest quintile of prudent diet, relative to the lowest quintile, was significantly associated with 34% reduced colorectal adenoma risk overall (incidence rate ratio, IRR=0.66; 95% CI, 0.50-0.87; p for trend, &amp;lt; 0.01). Higher scores on the Western pattern were associated with higher risk of colorectal adenoma (IRR = 1.42, 95% CI 1.09-1.85 for the highest quintile relative to the lowest; p trend, 0.01). Conclusion: Our findings suggest that African American women may be able to reduce their risk of developing colorectal adenomas by following a prudent dietary pattern and avoiding a more Western pattern. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1925. doi:10.1158/1538-7445.AM2011-1925

Systematic literature review and pooled analyses of risk factors for finding adenomas at surveillance colonoscopy

Colorectal cancer (CRC) screening guidelines recommend surveillance after polypectomy. There is variation in the surveillance intervals that are being advised. This variation also affects adherence. Surveillance intervals need to be based on risk factors at index. We therefore aimed to systematically review risk factors of adenoma findings at surveillance colonoscopy. A systematic literature search was performed up to September 2009. Studies that reported on follow-up colonoscopy findings with stratification for index characteristics were included. Pooled relative risks (RR) were calculated using random effects models, and heterogeneity was determined by means of the I2-statistic. A total of 27 studies met the inclusion criteria. The most important risk factors for adenoma findings were the presence on index colonoscopy of the following: advanced adenomas (RR: 1.81), ≥ 3 adenomas (RR: 1.64), size ≥ 10 mm (RR: 1.66), and age ≥ 60 years (RR: 1.65). The presence of villous adenomas, high grade dysplasia, proximal adenomas, and male gender were associated with less profound increases in RR. Marked variation in study design and substantial heterogeneity between studies was observed. Convincing evidence exists that patients with advanced adenomas, ≥ 3 adenomas, adenomas ≥ 10 mm, or age ≥ 60 years have an increased risk of adenoma recurrence. The evidence for other baseline findings for an increased risk of adenoma recurrence is inconclusive. Marked variation and consistently lower RRs in studies of medium or low quality emphasize the necessity for well performed and well reported studies. Given the high impact of surveillance on patients and service providers, there is need for further assessment of the risk(s) of adenoma recurrence.

Elevated risk of colorectal adenoma with Helicobacter pylori‐related chronic gastritis: A population‐based case‐control study

This study investigated correlations between Helicobacter pylori infection or chronic atrophic gastritis (CAG) and risk of colorectal adenoma in a population-based case-control study. Subjects comprised asymptomatic, middle-aged, male Japanese factory workers who participated in an annual health check-up program, including cancer screening with colonoscopy. We selected 239 colorectal adenoma cases based on histological evaluation and 239 age-matched adenoma-free controls, and evaluated colorectal adenoma risk according to stage of H. pylori-related chronic gastritis as determined by serum tests for H. pylori antibody titer and pepsinogen. Subjects with colorectal adenoma were more likely to be smokers and have hypercholesterolemia. H. pylori infection was a risk factor for adenoma as a whole (crude odds ratio [OR]: 2.26, 95% confidence interval [CI]: 1.44-3.55). Analysis of distal adenoma cases showed that adenoma risk was significantly increased in the presence of H. pylori infection, but there was no further increase in risk with CAG. In contrast, proximal adenoma risk increased stepwise with the presence and progression of H. pylori-related chronic gastritis and showed a maximal and significant increase with CAG (crude OR: 4.51, 95% CI: 1.43-14.2). Subjects with more extensive and severe gastritis showed still higher risk not only for proximal but also for distal adenoma. H. pylori-related chronic gastritis is likely to be involved in the development of colorectal neoplasms, and its progression appears to increase the risk, particularly for proximal adenomas. Knowing the H. pylori-related chronic gastritis stage will probably be useful for evaluation of risk for colorectal neoplasia.

Prevalence of colonic adenomas in patients with nonalcoholic fatty liver disease

Epidemiologic data suggest that colonic adenomas have an increased tendency to occur in patients who are obese, African American, or have a positive family history of colon cancer, or diabetes mellitus. Recent data suggest that impaired glucose tolerance, dyslipidemia, and metabolic syndrome are associated with a higher risk for colonic adenomas. Patients with nonalcoholic fatty liver disease (NAFLD) often share several of the aforementioned risk factors for colonic adenomas. However, data are lacking about the relationship between NAFLD and colonic adenomas. The aim of this study was to systematically evaluate whether NAFLD is an independent risk factor for colonic adenomas. We performed a retrospective cohort observational study on 233 patients who underwent screening colonoscopies at Brooke Army Medical Center from November 2007 to March 2010 to assess for the association between NAFLD and colonic adenomas. Patients who had previously been found to have biopsy-proven simple steatosis (n = 65) or nonalcoholic steatohepatitis (NASH) (n = 29) were compared with a control group without fatty liver disease on sonographic imaging (n = 139). Patients were stratified based on gender, race, body mass index (BMI), and family history and adjusted for variables previously known to be associated with increased adenoma risk. The mean age was 54.7 ± 6.0 years (48.5% women). Racial demographics were: 62.7% White, 18.5% Hispanic, 13.7%, African American, and 5.2% other. The mean BMI was 29.7 ± 5.8. The prevalence of colonic adenomas was 25.1% in the control group and 24.4% in the NAFLD group to include simple steatosis and NASH (p = 1.00). Furthermore, when adjusting for known confounders to include race, BMI, and family history no significant differences were found (p = 0.33). However, the ultrasound-negative patients ranked lower in the number of adenomas per person (p = 0.016). There was no difference in the prevalence of colonic adenomas when comparing the NAFLD group who had undergone colonoscopy with a group of control patients without NAFLD who had undergone colonoscopy. However, patients with negative ultrasounds appeared to have a lower polyp burden.

A Prospective Evaluation of C-reactive Protein Levels and Colorectal Adenoma Development

Inflammation is hypothesized to play a role in colorectal tumorigenesis. Circulating levels of C-reactive protein (CRP), a serologic marker of the inflammatory response, have been positively associated with colorectal cancer development in some studies; however, there are limited data on the relation of CRP with colorectal adenomas, established precursors of colorectal cancer. A nested case-control investigation of CRP levels and incident colorectal adenoma was conducted in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, a randomized trial of 154,942 individuals designed to test the efficacy of flexible sigmoidoscopy on colorectal cancer mortality when performed once, and then repeated 3 to 5 years later. Serum CRP levels were measured in baseline blood specimens from participants who were free of polyps in the left-sided colorectum at the baseline screening procedure, but who were found at the subsequent screen to have at least one colorectal adenoma (n=356), and in a set of polyp-free, frequency-matched controls (n=396). In a multivariable logistic regression model that included established colorectal adenoma risk factors, a 1-unit increase in log CRP level was associated with a 15% reduction in risk of developing colorectal adenoma (OR=0.85, 95% CI, 0.75-0.98, Ptrend=0.01). This association did not differ according to body size, smoking behavior, gender, use of nonsteroidal antiinflammatory drugs, or adenoma location. High circulating CRP levels may be protective against colorectal adenoma development. Though at contrast with mechanistic data on inflammation and colorectal tumorigenesis, this finding is not inconsistent with prior results on CRP and colorectal adenoma and warrants further investigation.

Risk factors for advanced lesions undetected at prior colonoscopy: not always poor preparation

Colonoscopy is regarded as the gold standard for diagnosis of colonic lesions. However, adenoma miss rates in tandem colonoscopy studies vary from 2 % to 26 %. We aimed to investigate the rates of advanced neoplasia in patients with a prior normal colonoscopy in an outpatient endoscopy unit. Review of reports for colonoscopies performed in our Endoscopy Unit from 2000 to 2005. Undetected lesions were defined as advanced adenoma or colorectal cancer (CRC) not reported in a colonoscopy performed in the previous 2 or 3 years, respectively. Patients with hereditary nonpolyposis CRC (HNPCC) and familial adenomatous polyposis (FAP) were excluded. Between 2002 and 2005, 795 patients were diagnosed with at least one advanced adenoma and 386 with CRC. Among these, 107/795 patients (13.5 %) had advanced adenoma that had been undetected in a previous colonoscopy (39 % [53/135 lesions] in the right colon); 92/107 (86 %) had an undetected advanced adenoma ≥ 10 mm. Previously undetected CRCs were found in 27/386 patients (6.7 %), located in the left colon in 21/27 (78 %); in 7 the area had not been reached in the previous colonoscopy. Risk factors for undetected advanced adenoma were advanced age, male gender, the presence of another advanced adenoma at first colonoscopy, and history of advanced neoplasia. Failure to detect advanced neoplasia is common in a community-based endoscopy facility. Previously undetected advanced lesions are more frequently found in the left colon and rectum. Risk factors for non-detection of advanced adenoma are similar to those for advanced neoplasia recurrence. Lowering non-detection rates is crucial for correct follow-up recommendations. Patients should be aware of rates of detection of advanced neoplasia after previous normal colonoscopic findings.

The comparison of the clinical manifestations and risk factors of colorectal cancer and adenomas: results from a colonoscopy-based study in southern Chinese

Colorectal cancer (CRC) is one of the most common gastrointestinal tumors in the world. This study aimed to compare the clinical manifestations and risk factors of CRC and adenomas in native patients of Guangzhou. Patients who underwent colonoscopy for the first time at Nanfang Hospital between July 2008 and July 2009 were recruited. Data on demographic information, main clinical manifestations, results of endoscopies and pathology, and possible risk factors of colorectal tumor were collected. Chi-square test and logistic regression were used to compare the clinical characteristics and risk factors for CRC and adenomas. Hematochezia and body weight loss were more frequent in proximal and distal CRC groups, respectively (P ≤ 0.05). Older age [odds ratio (OR), 1.079; 95% confidence interval (CI), 1.065-1.093], smoking status (OR, 1.712; 95% CI, 1.158-2.531), BMI =18.5-24.9 and ≥ 25.0 (OR, 2.384; 95% CI, 1.250-4.549; OR, 2.162; 95% CI, 1.044-4.478, respectively) were significant risk factors for advanced adenoma, while female (OR, 0.638; 95% CI, 0.429-0.949) and using aspirin (OR, 0.188; 95% CI, 0.042-0.845) were significant protective factors. Hyperlipemia (OR, 0.109; 95% CI, 0.013-0.886) was identified as a protective factor for proximal CRC. Smoking (OR, 1.717; 95% CI, 1.093-2.696), drinking (OR, 1.817; 95% CI, 1.145-2.883), DM history (OR, 2.204; 95% CI, 1.044-4.652) were identified as independent risk factors for distal CRC, and using aspirin (OR, 0.190; 95% CI, 0.043-0.840) was a protective factor. Drinking (OR, 3.288; 95% CI, 1.546-6.994; OR, 1.862; 95% CI, 1.037-3.343, respectively) was an independent risk factor for both poorly to moderately differentiated CRC and well-differentiated CRC. Besides, DM (OR, 3.761; 95% CI, 1.615-8.762) and hypertension (OR, 0.384; 95% CI, 0.178-0.828) were identified as independent risk factor and protective factor for well-differentiated CRC, respectively. Hematochezia and body weight loss were representative manifestations for distal and proximal CRC, respectively. For southern Chinese the most important influential factors for colorectal tumor are age, smoking, drinking, nutritional state, DM, hypertension, and the use of aspirin.

T1050 Impact of Family History of Polyps on Prevalence and Risk Factors for Adenomas in 40-49 Year Old Individuals

T1050 Impact of Family History of Polyps on Prevalence and Risk Factors for Adenomas in 40-49 Year Old Individuals

Jejunal Cancer in Patients With Familial Adenomatous Polyposis

Familial adenomatous polyposis (FAP) is an inherited disease affecting approximately 1:10,000 newborns, characterized by the formation of numerous adenomas in the digestive tract. Surveillance and prophylactic treatment of colonic and duodenal manifestations of this disease have much influenced disease course and survival. In more recent years, it has become clear that adenoma formation in FAP patients is not restricted to the colon and duodenum. Accordingly, these adenomas might have malignant potential, although the actual risk is unknown. We report 3 cases of jejunal carcinoma in FAP patients and review data on incidence, prognosis, and risk factors of jejunoileal adenoma and carcinoma development in FAP. Three patients with FAP aged 71, 57, and 59 years developed advanced duodenal adenomatosis and a jejunal carcinoma, which was associated with poor prognosis in 2 patients. Jejunal adenomas in FAP patients are reported occasionally and can progress into adenocarcinoma with a poor prognosis. In the future a subset of FAP patients benefitting from jejunal surveillance should be identified.

Abstract 1867: DNA repair gene polymorphisms and tobacco smoking and the risk of colorectal adenoma

Abstract Genetic variants of DNA repair genes may contribute to their altered capacity to repair endogenous and exogenous DNA damage. Although rare mutations in mismatch repair genes are known to lead to hereditary non-polyposis colorectal cancer, to date studies investigating common single nucleotide polymorphisms (SNPs) in DNA repair genes and colorectal cancer or adenoma risk have only examined a small number of variants in a limited number of genes. We conducted a comprehensive analysis of DNA repair gene polymorphisms and colorectal adenoma risk using a nested case-control study in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Effect modification by smoking, which is a known risk factor for adenoma, was also explored. A total of 1,338 advanced, left-sided colorectal adenoma cases and 1,503 frequency-matched controls without evidence of a left-sided polyp on sigmoidoscopy were included in the current study. Using DNA extracted from blood specimens, 3,401 tag SNPs in 153 DNA repair genes were genotyped. Logistic regression was used to estimate the odds ratios (OR) and 95% confidence intervals (CI) for the associations between genetic variants and adenoma risk assuming a log-additive model for the genotype. Among Caucasians, 30 SNPs were associated with adenoma risk at p&amp;lt;0.01. The most significant finding was for a non-synonymous SNP in EXO1 (rs9350), which was predicted to be deleterious using the SIFT and PolyPhen databases. The C allele at EXO1 rs9350 was associated with a 1.30-fold increased risk (95% CI=1.11-1.51, P=0.001). The association appeared to be limited to smokers (OR=1.54, 95% CI=1.26-1.89) with the strongest risk for current smokers (OR=2.15, 95% CI=1.27-3.65), and an intermediate risk for former smokers (OR=1.45, 95% CI=1.14-1.82), compared to never smokers (OR=0.98, 95% CI=0.76-1.25) that exhibited no increased risk (Pinteraction=0.002). Among the top findings, a SNP (rs17503908) in ATM with an overall OR of 0.75 (95% CI=0.63-0.91) was also modified by smoking (Pinteraction=0.006); the T allele at ATM rs17503908 was protective among never smokers (OR=0.55, 95% CI=0.40-0.76) but not among smokers (OR=0.89, 95% CI=0.70-1.13). The study suggests that polymorphisms in EXO1 and ATM may be associated with risk of advanced colorectal adenoma with the effects modified by tobacco smoking status. Our findings warrant extended investigations of these associations for colorectal cancer risk. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1867.

S1550: Prevalence and Risk Factors for Adenomas in 40-49 Year Old Individuals With a Family History of Colon Cancer

S1550: Prevalence and Risk Factors for Adenomas in 40-49 Year Old Individuals With a Family History of Colon Cancer

Prevalence and risk of colorectal adenoma in asymptomatic Koreans aged 40–49 years undergoing screening colonoscopy

Colorectal cancer screening is recommended for average-risk persons beginning at age 50. However, information about the incidence and risk factors of precursor adenoma in preceding decades is limited. The aim of this study was to determine the prevalence and risk factors of colorectal adenoma in persons aged 40-49 years and to compare the data with those aged 30-39 years and 50-59 years. A cross-sectional study of 5254 asymptomatic subjects who underwent screening colonoscopy was conducted. Data were stratified by age into three groups: 608 aged 30-39 years, 1930 aged 40-49 years, and 2716 aged 50-59 years. Prevalence of overall adenomas was 10.4% in the 30-39 years age group, 22.2% in the 40-49 years age group, and 32.8% in the 50-59 years age group. Advanced adenoma was found in 0.7% of the 30-39 years age group, 2.7% of the 40-49 years age group, and 4.1% of the 50-59 years age group. In the 40-49 years age group, male sex and current smoking habits showed associations with low-risk adenoma after multiple adjustments. Moreover, male sex (odds ratio [OR] = 1.55, 95% confidence interval [CI]: 1.02-3.23), current smoking (OR = 1.58, 95%CI: 1.06-3.50), and family history of colorectal cancer (OR = 2.54, 95%CI: 1.16-5.56) were independent predictors of advanced adenoma in this age group. Prevalence of adenoma in subjects aged 40-49 years was higher than in previous studies. Male sex and current smoking habits along with a family history of colorectal cancer were associated with advanced adenoma in this age group.

Colonoscopy screening for individuals aged 40–49 years with a family history of stomach cancer in Korea

For asymptomatic individuals aged 40-49 years, screening for colorectal cancer is recommended only if individuals are at an increased risk. A family history of colon cancer (FHCRC) is considered to increase risk, however, whether family history of stomach cancer (FHSC) increases the risk of adenoma is not well known. We aimed to see whether FHSC increases the risk in asymptomatic individuals aged 40-49 years in Korea. Among asymptomatic individual aged 40-49 years who underwent colonoscopy screening, risk of adenoma was assessed according to FHCRC or FHSC. Of 3,160 individuals, male comprised 1,602 individuals (50.7%). FHCRC and FHSC was noticed in 163 (5.2%) and 227 (7.0%) individuals, respectively. Prevalence of adenoma was 31.9 %, 28.8%, and 22.3% for individuals with FHCRC, individuals with FHSC, and individuals without family history of cancer, respectively. FHSC was an independent risk factor for adenoma (odds ratio, 1.38; 95% confidence interval, 1.02-1.87, P = 0.039) in asymptomatic individuals aged 40-49 years. Compared with individuals with FHCRC, individuals with FHSC showed no difference in risk for adenoma (P = 0.347). As with individuals with FHCRC, individuals with FHSC might need to be considered as an individual with increased risk for adenoma. Therefore, earlier screening might be needed for asymptomatic individuals aged 40-49 years with FHSC in Korea.