Race and Prevalence of Large Bowel Polyps Among the Low-Income and Uninsured in South Carolina.

BACKGROUND: Compared to whites, blacks have higher colorectal cancer incidence and mortality rates and are at greater risk for early-onset disease. The reasons for this racial disparity are poorly understood, but one contributing factor could be differences in access to high-quality screening and medical care. AIMS: The present study was carried out to assess whether a racial difference in prevalence of large bowel polyps persists within a poor and uninsured population (n = 233, 124 blacks, 91 whites, 18 other) undergoing screening colonoscopy. METHODS: Eligible patients were uninsured, asymptomatic, had no personal history of colorectal neoplasia, and were between the ages 45-64 years (blacks) or 50-64 years (whites, other). We examined the prevalence of any adenoma (conventional, serrated) and then difference in adenoma/polyp type by race and age categories. RESULTS: Prevalence for ≥1 adenoma was 37 % (95 % CI 31-43 %) for all races combined and 36 % in blacks <50 years, 38 % in blacks ≥50 years, and 35 % in whites. When stratified by race, blacks had a higher prevalence of large conventional proximal neoplasia (8 %) compared to whites (2 %) (p value = 0.06) but a lower prevalence of any serrated-like (blacks 18 %, whites 32 %; p value = 0.02) and sessile serrated adenomas/polyps (blacks 2 %, whites 8 % Chi-square p value; p = 0.05). CONCLUSIONS: Within this uninsured population, the overall prevalence of adenomas was high and nearly equal by race, but the racial differences observed between serrated and conventional polyp types emphasize the importance of taking polyp type into account in future research on this topic.

Prevalence and features of colorectal lesions among Hispanics: A hospital-based study.

AIM: To evaluate the prevalence and characteristics of colorectal adenoma and carcinoma in an inner city Hispanic population. METHODS: We reviewed the reports of 1628 Hispanic patients who underwent colonoscopy at Howard University from 2000 to 2010. Advanced adenoma was defined as adenoma ≥ 1 cm in size, adenomas with villous histology, high grade dysplasia and/or invasive cancer. Statistical analysis was performed using χ(2) statistics and t-test. RESULTS: The median age of the patients was 54 years, 64.2% were females. Polyps were observed in 489 (30.0%) of patients. Adenoma prevalence was 16.8% (n = 273), advanced adenoma 2.4% (n = 39), and colorectal cancer 0.4% (n = 7). Hyperplastic polyps were seen in 6.6% of the cohort (n = 107). Adenomas predominantly exhibited a proximal colonic distribution (53.7%, n = 144); while hyperplastic polyps were mostly located in the distal colon (70%, n = 75). Among 11.7% (n = 191) patients who underwent screening colonoscopy, the prevalence of colorectal lesions was 21.4% adenoma, 2.6% advanced adenoma; and 8.3% hyperplastic polyps. CONCLUSION: Our data showed low colorectal cancer prevalence among Hispanics in the Washington DC area. However, the pre-neoplastic pattern of colonic lesions in Hispanics likely points toward a shift in this population that needs to be monitored closely through large epidemiological studies.

Retrospective study of colorectal cancer in Zimbabwe: colonoscopic and clinical correlates.

AIM: To compare differences in the frequency of colorectal cancer at colonoscopy in Zimbabwe according to ethnicity. METHODS: All lower gastrointestinal endoscopic procedures performed between January 2006 and December 2011 at a gastroenterology clinic in Harare, Zimbabwe were reviewed. The demographic characteristics, clinical indications, differences in bowel preparation and the endoscopic and histological diagnoses were compared between different ethnic groups with emphasis on colorectal cancer. The clinical and demographic characteristics and the endoscopic findings were compared using the student t-test and the χ2 test, while the clinical indications associated with a diagnosis of colorectal cancer were determined by logistic regression. RESULTS: All colonoscopies and sigmoidoscopies performed in 1236 Caucasians, 460 black Africans and 109 Asians were analysed. Colorectal cancer was diagnosed more frequently in the black African patients compared to Caucasians or Asians (10% vs 3%, 10% vs 2%, P<0.001). However, polyps were less common among black Africans (5%) compared to both Caucasians (8%) and Asians (9%) (P=0.03). Among patients with colorectal cancer, black Africans tended to be younger than Caucasians, who were over-represented in the oldest age category; 32 % vs 2% were less than 50 years and 41% vs 78% were older than 60 years (P<0.001). Anaemia and weight loss were associated with colorectal cancer in both black African [odds ratio (OR): 2.73 (95%CI: 1.33-5.61) and 3.09 (1.35-7.07)] and Caucasian patients [OR: 6.65 (95%CI: 2.93-15.09) and 3.47 (1.52-7.94)]. CONCLUSION: The likelihood of diagnosing colorectal cancer in patients referred for colonoscopy in Zimbabwe is at least as likely among black Africans as it is among Caucasians.

Linkage disequilibrium and haplotype analysis of COX-2 and risk of colorectal adenoma development.

Single nucleotide polymorphisms (SNPs) in the promoter and untranslated region of cyclooxygenase (COX)-2, an inducible enzyme responsible for the synthesis of prostaglandins, have been reported to modulate the risk for many human cancers. We performed comprehensive linkage disequilibrium (LD) and haplotype analyses of 13 single nucleotide polymorphisms of the COX-2 gene and examined its susceptibility to adenoma development in 72 African American cases and 142 controls. Results revealed significant variation in LD patterns with consequence for adenoma development. Two distinct haplotype blocks were identified; one block covered the coding regions of exon 1, introns and a section of the 3'-unstranslated region (3'-UTR), whereas the second block resided solely in the 3'-UTR region. A haplotype in block 1 increased the risk of adenoma development by threefold (odds ratio [OR]= 2.9, confidence interval [CI]= 1.8-3.7, P= 0.002). Regression analysis showed, increase in copies of minor alleles of 6,064(T>C) polymorphism associated with increased odds of adenoma development by 80% (OR = 1.80, CI = 1.09-3.21, P= 0.034), 10,848(G>A) by 84% (OR = 1.84, CI = 1.05-3.23, P= 0.034) and 10,935(A>G) by 32% (OR = 1.32, CI = 1.12-3.69, P= 0.036). These results support the hypothesis that COX-2 gene might play a role in the etiology of colon cancer and warrant further investigation in other cancers. Besides, these variations should be taken into account for disease-based association studies in which the COX-2 polymorphism is considered as a candidate gene. Clin Trans Sci 2012; Volume 5: 60-64.

Colorectal neoplasms in relation to non-alcoholic fatty liver disease in Korean women: a retrospective cohort study.

BACKGROUND AND AIM: Metabolic syndrome has been associated with an increased risk for colorectal cancer. Non-alcoholic fatty liver disease (NAFLD) is regarded as a hepatic manifestation of metabolic syndrome. We investigated whether NAFLD is associated with colorectal neoplasms in Korean women. METHODS: This retrospective cohort study included data from 5517 women, aged 35-80 years, who underwent life insurance company health examinations between July 2002 and June 2006. Fatty liver disease was assessed by abdominal ultrasound, with NAFLD defined as fatty liver disease in the absence of alcohol use of > 40 g/week or other secondary causes. The incidence of colorectal neoplasms through December 2008 was obtained through medical certificate codes for insurance claims. The association between NAFLD and the risk of colorectal neoplasms was estimated using standard Cox proportional hazards models. RESULTS: Of the study population, 15.1% were diagnosed with NAFLD. During follow-up, 65 women were verified as having adenomatous polyps and 15 as having colorectal cancer. Adjusted relative risks (95% confidence interval [CI]) for adenomatous polyps by age, low high-density lipoprotein-cholesterol, and NAFLD were 1.12 (95% CI 1.09-1.15), 2.56 (95% CI 1.53-4.28) and 1.94 (95% CI 1.11-3.40). Adjusted relative risks (95% CI) for colorectal cancer by age and NAFLD were 1.23 (95% CI 1.17-1.29) and 3.08 (95% CI 1.02-9.34). CONCLUSIONS: Our findings demonstrate a significant relationship between NAFLD and colorectal neoplasms. Among the various manifestations of metabolic syndrome, NAFLD may predict the development of colorectal neoplasms in Korean women.

The association of glycemic load and carbohydrate intake with colorectal cancer risk in the Multiethnic Cohort Study.

BACKGROUND: High-glycemic-load diets may increase colorectal cancer risk through hyperinsulinemic effects. OBJECTIVE: We analyzed data for 191,004 participants in the Multiethnic Cohort Study to determine the risk of colorectal cancer associated with glycemic load (GL), carbohydrate, and sucrose and to ascertain whether this risk was modified by sex and ethnicity. DESIGN: During 8 y of follow-up, 2379 incident cases of colorectal adenocarcinoma occurred. We used baseline quantitative food-frequency questionnaire data to assess usual dietary intake over the preceding year. Using Cox regression, we calculated adjusted relative risks (RRs) and 95% CIs for colorectal cancer associated with quintiles of GL, carbohydrate, and sucrose. RESULTS: For both men and women in this cohort, white rice was the major contributor to GL. In multivariate models, RRs for colorectal cancer decreased significantly with increasing GL in women (RR for the highest quintile versus the lowest: 0.75; 95% CI: 0.57, 0.97; P for trend = 0.02) but not in men (RR: 1.15; 95% CI: 0.89, 1.48; P for trend = 0.19). Results for carbohydrate and sucrose were similar. The inverse association with GL was found in women of all ethnic groups (P for interaction = 0.58). In men, an interaction was found between ethnicity and GL (P < 0.01): white men had a positive association with increasing GL (RR: 1.69; 95% CI: 0.98, 2.92; P for trend < 0.01), but men of other ethnic groups did not. CONCLUSION: GL and carbohydrate intake appear to protect against colorectal cancer in women in the Multiethnic Cohort, perhaps because a major source of GL is white rice.

Association between BMI and metabolic syndrome and adenomatous colonic polyps in Korean men.

Obesity and insulin resistance are associated with the risk of colon cancer. Adenomatous colonic polyps are precancerous lesions of colon cancer. We investigated whether BMI and the metabolic syndrome are associated with the presence of adenomatous colonic polyps in Korean men. Anthropometric measurements, metabolic risk factors, and colonoscopic pathologic findings were assessed in 1,898 men who underwent routine colonoscopy at the Health Promotion Center of Asan Medical Center in 2005. The modified National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) and International Diabetes Federation (IDF) criteria were used for the definition of the metabolic syndrome. Multiple logistic regression analysis was used to evaluate the association between BMI and the metabolic syndrome and adenomatous polyps. Compared with men in the 1st quintile of the BMI, the adjusted odds ratio (OR) and 95% confidence interval (CI) for adenomatous polyps in men in the 2nd, 3rd, 4th, and 5th quintiles of the BMI were 1.55 (1.10-2.19), 1.57 (1.10-2.24), 1.94 (1.34-2.81), and 1.99 (1.31-3.01), respectively (P for trend <0.0001). Men with triglycerides (TGs) > or = 150 mg/dl were significantly more likely to have adenomatous polyps than were men with TG <150 mg/dl (OR 1.29; 95% CI 1.03-1.62). As a function of the number of metabolic risk factors, the ORs for adenomatous polyps were 1.41 (1.03-1.93), 1.52 (1.08-2.12), 1.46 (1.01-2.12), and 1.77 (1.08-2.90) for 1, 2, 3, and > or = 4 risk factors, respectively (P for trend <0.05). Adenomatous colonic polyps were significantly associated with increased BMI levels. Subjects with even one component of the metabolic syndrome had a significantly higher risk for developing adenomatous polyps compared to those subjects without any component in Korean men.

Change in body size and the risk of colorectal adenomas.

Adiposity has been recognized as a risk factor for colorectal adenoma, but the influence of weight gain, adipose tissue distribution, and possible differences between ethnic/racial and gender groups remains unanswered. The aim of this prospective study was to examine the association between adiposity and weight change and colorectal adenoma risk. Over approximately 10-year period, anthropometric measures and other risk factors were measured at three time points in the multicenter multiethnic Insulin Resistance Atherosclerosis Study cohort. Colonoscopies were then conducted on 600 cohort participants regardless of symptoms whose mean age at colonoscopy was 64 years. Multivariate logistic regression analyses were used to assess the association between colorectal adenomas and measures of adiposity and weight change over the approximately 10-year period before colonoscopy. Obesity was positively associated with risk of colorectal adenomas at the time of colonoscopy [adjusted odds ratio (OR(adj)), 2.16; 95% confidence interval (95% CI), 1.13-4.14] and was stronger in women (OR(adj), 4.42; 95% CI, 1.53-12.78) than in men (OR(adj), 1.26; 95% CI, 0.52-3.07). The risk of adenomas increased among participants who gained weight compared with those who maintained weight over the approximately 5 years (OR(adj), 2.30; 95% CI, 1.25-4.22) and approximately 10 years (OR(adj), 2.12; 95% CI, 1.25-3.62). These associations were similar for both advanced and nonadvanced adenomas. These results suggest a positive association between obesity, weight gain, and colorectal adenoma risk. Stronger associations were observed when obesity was measured at the time of colonoscopy, suggesting that obesity may be a promoting factor in the growth of colorectal adenomas.

Choice of screening modality in a colorectal cancer education and screening program for the uninsured.

BACKGROUND: Starting in 2001, the state of Maryland established a carefully planned and executed multicomponent intervention to reduce mortality and disparities in colorectal cancer. METHODS: In the most populous county, uninsured participants received education and a choice of free screening by fecal occult blood testing (FOBT) or colonoscopy or both. RESULTS: Over 2 years, a group of 1,672 uninsured individuals, of whom 90% were minorities, registered with the program. Overall, screening uptake was 41% with colonoscopy, 10% with FOBT, and 10% with both FOBT and colonoscopy. CONCLUSION: The choices of colorectal cancer screening modalities by a diverse uninsured population demonstrates the importance of maintaining screening options.

Legume intake and reduced colorectal adenoma risk in African-Americans.

Colorectal adenomas are known precursors for colorectal cancer. Several studies have shown that dietary factors can influence adenoma formation and growth. This study was conducted using African-American men and women who were undergoing colonoscopies in order to examine the relationship between selected dietary factors and the risk for colon polyps. In a case-control design, 186 men and women with a mean of 58 years of age were studied. A multiple logistic regression model was used to adjust for potential confounding variables and to determine which factors influence colorectal adenoma risk. Study results revealed that consumption of legumes such as dried beans, split peas, or lentils was negatively associated with risk (OR = 0.19; 95% CI: 0.04-0.91). Legumes are a good source of dietary fiber and of phytochemical compounds that may play a role in reducing adenoma formation or growth, thereby decreasing the risk of colorectal cancer. Nurses working with African-Americans should encourage consumption of these foods to decrease this risk.

APC I1307K increases risk of transition from polyp to colorectal carcinoma in Ashkenazi Jews.

BACKGROUND & AIMS: The I1307K allele of the APC gene has been shown to confer a modestly elevated risk of colorectal cancer in the Ashkenazi Jewish population (relative risk, 1.5-1.7). However, it is unclear whether the alteration predisposes to adenomas and whether the genetic information can be used in clinical practice. To further address the pathogenic significance of I1307K, we offered both a genetic test and a screening program to individuals considered to be at increased risk for colorectal cancer. We compared the prevalence of polyps and their characteristics between carriers and noncarriers. METHODS: Invitations to participate in a DNA and colonoscopy screening program were mailed, together with a family questionnaire, to 3540 households forming the Jewish Community in Ottawa. The I1307K variant was analyzed in 242 eligible respondents who were selected because they had a personal or family history of colon cancer. Nearly 80% of these respondents (n = 189; age range, 32-83 years) consented to undergo a single colonoscopic examination. RESULTS: The overall carrier frequency of I1307K in the study group was 10.3%. A higher proportion of heterozygous gene carriers was found in the subgroup of colon cancer survivors (27%) than among asymptomatic individuals (8%, P < 0.02). A total of 59 polyps were identified in 44 subjects. Histologically confirmed adenomatous polyps were diagnosed in 11.8% of carriers and 12.8% of noncarriers (P > 0.5). No significant differences in polyp size, multiplicity, location, degree of villosity, or age-dependent prevalence were found between the 2 groups of participants. CONCLUSIONS: The high frequency of I1307K colorectal cancer patients found in the Ashkenazi Jewish community of Ottawa and the equivalent proportion of carriers and noncarriers who developed adenomatous polyps suggest that in this community, I1307K is associated with a significant predisposition to carcinoma but not adenoma.

Hereditary nonpolyposis colon cancer: analysis of linkage to 2p15-16 places the COCA1 locus telomeric to D2S123 and reveals genetic heterogeneity in seven Canadian families.

Hereditary nonpolyposis colon cancer (HNPCC) is an autosomal dominant trait responsible for approximately 6% of colorectal cancers. Linkage of the HNPCC trait to the D2S123 locus on 2p15-16 has previously been reported in two families. This HNPCC locus is now designated "COCA1." We have tested seven Canadian HNPCC families, who have a variety of clinical presentations, for linkage to a panel of microsatellite polymorphisms in the vicinity of D2S123. One family was clearly linked to the COCA1 locus (LOD = 4.21), and a second family is likely to be linked (LOD = 0.92). In three families linkage was excluded. In the remaining two families the data were inconclusive. In the linked family, individuals with cancer of the endometrium or ureter share a common haplotype with 12 family members with colorectal cancer. This supports the suspected association between these extracolonic neoplasms and the HNPCC syndrome. In addition, five of the six individuals with adenomatous polyps (but no colorectal cancer) have the same haplotype as the affected individuals, while the sixth carries a recombination. One individual with colorectal cancer carries a recombination that places the COCA1 locus telomeric to D2S123. This study localizes the COCA1 gene to an 8-cM region that is consistent with the location of the hMSH2 gene. We also confirm that families presently classified as HNPCC are genetically heterogeneous.

Ethnic differences in the recurrence of adenomatous polyps after colonoscopic polypectomy.

A retrospective study was done of polyp recurrence rates following an initial clearing colonoscopy for adenomatous polyps. The intent of the study was to identify risk factors that would predict a greater risk for recurrence in Hawaii's ethnically diverse population. When the initial exam detected multiple polyps, a higher recurrence rate was found in Caucasian patients.