Risk of advanced proximal neoplasms in asymptomatic adults according to the distal colorectal findings

Modifiable endoscopic factors that influence the adenoma detection rate in colorectal cancer screening colonoscopies

BACKGROUND

Adenoma detection rate (ADR) has become the most important quality indicator for colonoscopy.

OBJECTIVE

The aim of this study was to investigate which modifiable factors, directly related to the endoscopic procedure, influenced the ADR in screening colonoscopies.

DESIGN

Observational, nested study.

SETTING

Multicenter, randomized, controlled trials.

PATIENTS

Asymptomatic people aged 50 to 69 years were eligible for a multicenter, randomized, controlled trial designed to compare colonoscopy and fecal immunochemical testing in colorectal cancer screening. A total of 4539 individuals undergoing a direct screening colonoscopy were included in this study.

INTERVENTION

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

Bowel cleansing, sedation, withdrawal time in normal colonoscopies, and cecal intubation were analyzed as possible predictors of adenoma detection by using logistic regression analysis, adjusted for age and sex.

RESULTS

In multivariate analysis, after adjustment for age and sex, factors independently related to the ADR were a mean withdrawal time longer than 8 minutes (odds ratio [OR] 1.51; 95% CI, 1.17-1.96) in normal colonoscopies and split preparation (OR 1.26; 95% CI, 1.01-1.57). For advanced adenomas, only withdrawal time maintained statistical significance in the multivariate analysis. For proximal adenomas, withdrawal time and cecal intubation maintained independent statistical significance, whereas only withdrawal time longer than 8 minutes and a <10-hour period between the end of preparation and colonoscopy showed independent associations for distal adenomas.

LIMITATIONS

Only endoscopic variables have been analyzed.

CONCLUSION

Withdrawal time was the only modifiable factor related to the ADR in colorectal cancer screening colonoscopies associated with an increased detection rate of overall, advanced, proximal, and distal adenomas.

Predictors of colorectal cancer testing using the California Health Inventory Survey

AIM: To identify key variables associated with colon cancer testing using the 2009 California Health Inventory Survey (CHIS).

METHODS: The CHIS has been conducted biennially since 2001 using a two-stage, geographically stratified random-digit-dial sample design to produce a representative sample of the entire State. For this study we used survey data from 2001-2009 inclusive. We restricted our analysis to White, Black, and Hispanic/Latinos aged 50-80 years. Weighted data was used to calculate the proportion of participants who underwent some form of colon cancer testing (colonoscopy, flexible sigmoidoscopy or fecal occult blood testing) within the previous 5 years stratified by race/ethnicity. For inferential analysis, boot-strapping with replacement was performed on the weighted sample to attain variance estimates at the 95%CI. For mean differences among categories we used t-tests and for comparisons of categorical data we used Pearson’s χ². Binary logistic regression was used to identify independent variables associated with undergoing some form of testing. Trend analysis was performed to determine rates of testing over the study period stratified by race.

RESULTS: The CHIS database for 2009 had 30 857 unique respondents corresponding to a weighted sample size of 10.6 million Californians. Overall, 63.0% (63.0-63.1) underwent a colon cancer test within the previous 5 years; with 70.5% (70.5%-70.6%) of this subset having undergone colonoscopy. That is 44.5% (44.4%-44.5%) of all individuals 50-80 underwent colonoscopy. By multivariable regression, those tested were more likely to be male (OR = 1.06; 95%CI: 1.06-1.06), Black (OR = 1.30; 95%CI: 1.30-1.31), have a family member with colon cancer (OR = 1.71; 95%CI: 1.70-1.72), and have health insurance (OR = 2.71; 95%CI: 2.70-2.72). Progressive levels above the poverty line were also associated with receiving a test (100%-199%: 1.21; 1.20-1.21), (200%-299%:1.41; 1.40-1.42), (> 300:1.69; 1.68-1.70). The strongest variable was physician recommendation (OR = 3.90; 95%CI: 3.88-3.91). For the Hispanic/Latino group, additional variables associated with testing were success of physician-patient communication (OR = 2.44; 95%CI: 2.40-2.48) and naturalized citizenship status (OR = 1.91; 95%CI: 1.89-1.93). Trend analysis demonstrated increased colon cancer testing for all racial/ethnic subgroups from 2001-2009 although the rate remained considerably lower for the Hispanic/Latino subgroup.

CONCLUSION: Using CHIS we identified California citizens most likely to undergo colon cancer testing. The strongest variable associated with testing for all groups was physician recommendation.

Nurse observation during colonoscopy increases polyp detection: a randomized prospective study

OBJECTIVES

To determine whether a second observer during colonoscopy increases adenoma detection.

METHODS

Consecutive patients undergoing screening colonoscopy were prospectively randomized to routine colonoscopy or physician and nurse observation during withdrawal.

RESULTS

Of 502 patients, 249 were randomized to routine colonoscopy, and 253 to physician plus nurse observation during withdrawal. A total of 592 polyps were detected, 40 identified by the endoscopy nurse only. With nurse observation, 1.32 polyps and 0.82 adenomas were found per colonoscopy, vs. 1.03 polyps and 0.64 adenomas in the routine group, demonstrating a 1.29-fold and a 1.28-fold increase in the average number of polyps and of adenomas detected, respectively. The overall adenoma detection rate (ADR) was 44.1%, with trends toward increased ADR and all-polyp detection rate with nurse observation.

CONCLUSIONS

Nurse observation during colonoscopy resulted in an increase in the number of polyps and adenomas found per colonoscopy, along with a trend toward improved overall ADR and all-polyp detection rate.

Role of preoperative colonoscopy in patients with gastric cancer: a case control study of the prevalence of coexisting colorectal neoplasms

BACKGROUND

We evaluated the prevalence of coexisting asymptomatic colorectal neoplasm (CRN) in patients with gastric cancer (GC).

METHODS

Preoperative colonoscopic examinations were performed in 495 patients with GC who underwent gastrectomy between January 2009 and December 2010. To compare the prevalence of CRN in these patients with that in a normal population, we selected 495 sex- and age-matched persons who underwent colonoscopies for health screening. Risk factors for CRN were evaluated by univariate and multivariate analyses.

RESULTS

The overall incidence of CRN was 41.8 % (414/990). The prevalence of overall CRN, high-risk CRN, and colorectal carcinoma (CRC) were significantly higher in the GC group than in the control group (overall CRN: 48.9 % vs. 34.7 %; high-risk CRN: 28.3 % vs. 13.5 %; CRC: 2.6 % vs. 0.2 %; all P < 0.001). The presence of GC [odds ratio (OR), 1.82; 95 % confidence interval (CI), 1.4-2.38; P < 0.001], age ≥50 years (OR, 2.58; 95 % CI, 1.75-3.81; P < 0.001), and male sex (OR, 2.28; 95 % CI, 1.72-3.02; P < 0.001) were risk factors for overall CRN. In patients with GC, age ≥40 years (OR, 3.22; 95 % CI, 1.24-8.37; P = 0.016) and male sex (OR, 3.21; 95 % CI, 2.17-4.76; P < 0.001) were risk factors for overall CRN.

CONCLUSIONS

The prevalence of coexisting CRN, including CRC, was higher in patients with GC than in the normal population. Preoperative colonoscopy is strongly indicated in patients with GC who are male and/or ≥40 years of age.

Shortened surveillance intervals following suboptimal bowel preparation for colonoscopy: results of a national survey

PURPOSE

Suboptimal bowel preparation can result in decreased neoplasia detection, shortened surveillance intervals, and increased costs. We assessed bowel preparation recommendations and the relationship to self-reported proportion of suboptimal bowel preparations in practice; and evaluated the impact of suboptimal bowel preparation on colonoscopy surveillance practices. A random sample of a national organization of gastroenterologists in the U.S. was surveyed.

METHODS

Demographic and practice characteristics, bowel preparation regimens, and proportion of suboptimal bowel preparations in practice were ascertained. Recommended follow-up colonoscopy intervals were evaluated for optimal and suboptimal bowel preparation and select clinical scenarios.

RESULTS

We identified 6,777 physicians, of which 1,354 were randomly selected; 999 were eligible, and 288 completed the survey. Higher proportion of suboptimal bowel preparations/week (≥10 %) was associated with hospital/university practice, teaching hospital affiliation, >25 % Medicaid insured patients, recommendation of PEG alone and sulfate-free. Those reporting >25 % Medicare and privately insured patients, split dose recommendation, and use of MoviPrep® were associated with a <10 % suboptimal bowel preparations/week. Shorter surveillance intervals for three clinical scenarios were reported for suboptimal preparations and were shortest among participants in the Northeast who more often recommended early follow-up for normal findings and small adenomas. Those who recommended 4-l PEG alone more often advised <1 year surveillance interval for a large adenoma.

CONCLUSIONS

Our study demonstrates significantly shortened surveillance interval recommendations for suboptimal bowel preparation and that these interval recommendations vary regionally in the United States. Findings suggest an interrelationship between dietary restriction, purgative type, and practice and patient characteristics that warrant additional research.

Transparent cap colonoscopy versus standard colonoscopy to improve caecal intubation

BACKGROUND

Colonoscopy is considered the gold-standard investigation for screening and diagnosis of colorectal cancer. It is also becoming increasingly desirable for assessment, management, diagnosis and follow-up of other colorectal diseases, such as inflammatory bowel diseases and acute diverticulitis. Hence, due to the increasing demand for colonoscopy, devices to advance examination techniques are highly sought-after and the colonoscope with the transparent cap could be one of these.

OBJECTIVES

To identify and review all relevant data in order to determine whether colonoscopy with a transparent cap is a more effective diagnostic tool than colonoscopy.

SEARCH METHODS

We searched the MEDLINE, EMBASE and CINAHL databases, and the Cochrane Central Register of Controlled Trials for all randomised controlled trials (RCTs) comparing the use of colonoscopy with a transparent cap with standard colonoscopy.

SELECTION CRITERIA

Studies were included if they were randomised controlled trials which compared the use of colonoscopy with a transparent cap with standard colonoscopy.

DATA COLLECTION AND ANALYSIS

Data on study methods, participants, interventions used and outcomes measured was extracted from each study. Data was entered into the Cochrane Review Manager software (RevMan 5.0, 2008) and analysed using Cochrane MetaView.

MAIN RESULTS

In the present meta-analysis, we considered 14 randomised controlled trials so far published. The findings of our work indicate that colonoscopy with transparent cap has a faster caecal intubation time when compared with standard colonoscopy. Reviewing studies individually would also seem to favour colonoscopy with transparent cap for polyp detection rate and pain during procedure but due to lack of comparable data meta-analysis was not feasible.

AUTHORS' CONCLUSIONS

This review suggests that a transparent cap on the end of the colonoscope may give a marginally faster caecal intubation time compared with standard colonoscopy. It also suggests that there is a better polyp detection rate and less pain with the cap. However, the authors feel that further randomised controlled trials in this area would provide more clinically significant information on this adjunct to colonoscopy.

Impact of a family history of colorectal cancer on the prevalence of advanced neoplasia at colonoscopy in 4,967 asymptomatic patients

BACKGROUND AND AIMS

A family history of colorectal cancer is considered an independent risk factor for advanced neoplasia at colonoscopy. The expected outcome for screening colonoscopy in patients with a family history is not well established in all populations.

METHODS

We designed a large, prospective study of an unselected population in San Diego, California to assess the impact of a family history of colorectal cancer on the prevalence of advanced neoplasia on screening colonoscopy.

RESULTS

We evaluated 6,905 consecutive patients referred for colonoscopy between January 2005 and December 2006. Of the 4,967 who met the inclusion criteria, the mean age was 58.8 and consisted of 58.6% women. Overall 930 (18.7%) had neoplasia and 249 (5%) had advanced neoplasia, eight (0.16%) of which were cancer. The 4,967 patients were divided into 643 with and 4,324 without a family history of colorectal cancer. Of the 643 patients with a family history, 38 (5.9%) had advanced neoplasia, one of which was cancer. Of the 4,324 patients without a family history, 211 (4.9%) had advanced neoplasia including seven cancers. The relative risk for finding advanced neoplasia in patients with a single affected first degree relative was 1.21 (95% CI, 0.87-1.69; P = 0.31).

CONCLUSIONS

A family history of one first-degree relative with colorectal cancer did not predict a significantly higher prevalence of advanced neoplasia at screening colonoscopy in this Southwestern cohort.

Tailoring colorectal cancer screening by considering risk of advanced proximal neoplasia

BACKGROUND

Quantifying the risk of advanced proximal colorectal neoplasia might allow tailoring of colorectal cancer screening, with colonoscopy for those at high risk and less invasive screening for very low-risk persons.

METHODS

We analyzed findings from 10,124 consecutive adults aged≥50 years who underwent screening colonoscopy to the cecum. We quantified the risk of advanced neoplasia (tubular adenoma≥1 cm, a polyp with villous histology or high-grade dysplasia, or adenocarcinoma) both proximally (cecum to splenic flexure) and distally (descending colon to anus). The prevalence of advanced proximal neoplasia was quantified by age, gender, and distal findings.

RESULTS

The mean (standard deviation) age was 57.5 (6.0) years; 44% were women; 7835 (77%) had no neoplasia, and 1856 (18%) had 1 or more nonadvanced adenomas. Overall, 433 subjects (4.3%) had advanced neoplasia (267 distally, 196 proximally, 30 both), 33 (0.33%) of which were adenocarcinoma (18 distal, 15 proximal). The risk of advanced proximal neoplasia increased with age decade (1.13%, 2.00%, and 5.26%, respectively; P=.001) and was higher in men (relative risk [RR], 1.91; confidence interval [CI], 1.32-2.77). In women aged less than 70 years, the risk was 1.1% overall (vs 2.2% in men; RR, 1.98; CI, 1.42-2.76) and 0.86% in those with no distal neoplasia (vs 1.54% in men; RR, 1.81; CI, 1.20-2.74).

CONCLUSIONS

Risk of advanced proximal neoplasia is a function of age and gender. Women aged less than 60 to 70 years have a very low risk, particularly those with no distal adenoma. Sigmoidoscopy with or without occult blood testing may be sufficient and even preferable for screening these subgroups.

Risk stratification for advanced proximal colon neoplasm and individualized endoscopic screening for colorectal cancer by a risk-scoring model

BACKGROUND

Only 30% to 40% of patients with advanced proximal neoplasms (APN) have distal colon neoplasms.

OBJECTIVE

To develop a risk score model for APN and propose an individualized screening protocol for colorectal cancer.

DESIGN

Retrospective cohort study.

SETTING

Tertiary-care center.

PATIENTS

Derivation cohort (6200 adults) and validation cohort (1389 adults).

INTERVENTION

Screening colonoscopy.

MAIN OUTCOME MEASUREMENTS

An APN risk score model was developed from the derivation cohort (6200 adults) and was tested in the validation cohort (1389 adults), who underwent screening colonoscopy.

RESULTS

Age, male sex, and smoking were clinical risk factors for APN. The presence of a distal neoplasm was a sigmoidoscopic risk factor for APN. We calculated APN risk scores (0-8) based on these variables and classified patients as low risk (0-2) or high risk (3-8). In the validation cohort, the relative risk of APN was 3.5-fold higher in the high-risk group than in the low-risk group. Our model suggests that colonoscopy should be performed as an initial screening test in patients with a high clinical risk for APN. Sigmoidoscopy should be performed initially in patients with low clinical risk for APN followed by supplementary colonoscopy in those with high APN risk scores based on both clinical and sigmoidoscopic risk factors. This protocol detected APN in 22 of 34 APN+ patients (64.7%) with little increase in the endoscopy burden, whereas only 16 of 34 APN+ patients (47.1%) would be identified by initial sigmoidoscopy followed by colonoscopy only in cases with distal neoplasms.

LIMITATIONS

Retrospective design.

CONCLUSION

Our APN risk score model provides an algorithm for efficient screening of colorectal cancer by sigmoidoscopy and colonoscopy.

Rate of serious complications of colonoscopy in Quebec

BACKGROUND

The rate of serious complications is one marker of the quality of colonoscopy services.

OBJECTIVE

To estimate the rate of serious complications of colonoscopy according to colonoscopy indication and polypectomy status.

METHODS

A prospective cohort study of patients scheduled for colonoscopy who were recruited from seven endoscopy facilities across Montreal (Quebec) was conducted. Before colonoscopy, patients completed a brief questionnaire and provided their health insurance numbers. Colonoscopy indication was based on patient-reported medical history. Polypectomy status was obtained from provincial physician billing records (Régie de l'assurance maladie du Québec). Diagnoses and procedures associated with hospitalization in the 30 days following colonoscopy were obtained from the provincial hospitalization database (MedEcho).

RESULTS

Of the 2134 patients enrolled (mean age 60.9 years, 50.1% male), 33 (1.55% [95% CI 1.06% to 2.16%]) were hospitalized within 30 days. One patient experienced bleeding following a colonoscopy that involved polypectomy and was diagnosed with carcinoma in situ of the rectum. Based on self-reported rectal bleeding in the previous six months, the colonoscopy was nonscreening. The provincial hospitalization data showed no occurrences of perforation, diverticulitis, myocardial infarction⁄stroke or death; thus, the rate of serious colonoscopy complications was 0.05% (95% CI 0.00% to 0.26%).

DISCUSSION

The rate of serious colonoscopy complications requiring hospitalization was low and comparable with what is reported in the literature. The serious complication occurred subsequent to polypectomy and in a nonscreening colonoscopy.

CONCLUSION

The findings support the relative safety of screening colonoscopy in persons without large bowel diseases and symptoms. However, future research to determine the rate of serious complications not requiring hospitalization is warranted to reassure decision makers of the safety of colonoscopy for colorectal cancer screening.

Changing epidemiology of colorectal cancer makes screening sigmoidoscopy less useful for identifying carriers of colorectal neoplasms

BACKGROUND

There is renewed interest in flexible sigmoidoscopy (FS) colorectal cancer (CRC) screening following trials showing significantly reduced CRC incidence and mortality.

AIMS

To evaluate the potential usefulness of FS screening in our population.

METHODS

We examined rectosigmoid (RS) cancer epidemiology in our Jewish population using Israel National Cancer Registry data, computed by CRC site, age groups, and gender. We also reviewed endoscopy-screening publications for prevalence of RS and proximal advanced adenomas (AAP) and having both or either.

RESULTS

During 1980-2008, there were 64,559 CRCs registered; 31.6 % were RS cancer which has now decreased to 29 % of men's and 26 % of women's CRC (both P < 0.01). In <50 year olds, RS cancer occurred in 42 % of males' and 35 % of females' CRC, and in the last 2 decades this ratio is unchanged. In 50-74 year olds, RS cancer decreased to stable levels of 32 % of males' and 29 % females' CRC (both P < 0.01). In ≥75 year olds, RS cancer progressively decreased to 24 % of males' and 22 % females' CRC (both P < 0.001). From endoscopy screening reports in 40-79 year olds, RS AAPs occurred in 2.0-5.8 %, being least in women, most in men, and not increased with aging. Some 50-57 % of screenees had both RS and proximal AAPs, least when aged 40-49 years at 25 %, women were 35 %, and with aging 40 %, but most in men at 70 %.

CONCLUSIONS

With the changing CRC epidemiology, having fewer RS neoplasms but more proximal cancer, the effectiveness of FS screening for identifying significant neoplasms decreases with screenees' age and especially in females. These make FS screening less suitable for our aging and increasingly female population.

Colorectal endoscopy, advanced adenomas, and sessile serrated polyps: implications for proximal colon cancer

OBJECTIVES

Colonoscopy is associated with a decreased risk of colorectal cancer but may be more effective in reducing the risk of distal than proximal malignancies. To gain insight into the differences between proximal and distal colon endoscopic performance, we conducted a case-control study of advanced adenomas, the primary targets of colorectal endoscopy screening, and sessile serrated polyps (SSPs), newly recognized precursor lesions for a colorectal cancer subset that occurs most often in the proximal colon.

METHODS

The Group Health-based study population included 213 advanced adenoma cases, 172 SSP cases, and 1,704 controls aged 50-79 years, who received an index colonoscopy from 1998-2007. All participants completed a structured questionnaire covering endoscopy history. Participants with polyps underwent a standard pathology review to confirm the diagnosis and reclassify a subset as advanced adenomas or SSPs. Logistic regression analyses were conducted to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between endoscopy and advanced adenomas and SSPs separately; site-specific analyses were completed.

RESULTS

Previous endoscopy was inversely associated with advanced adenomas in both the rectum/distal colon (OR=0.38; 95% CI: 0.26-0.56) and proximal colon (OR=0.31; 95% CI: 0.19-0.52), but there was no statistically significant association between previous endoscopy and SSPs (OR=0.80; 95%CI: 0.56-1.13).

CONCLUSIONS

Our results support the hypothesis that the effect of endoscopy differs between advanced adenomas and SSPs. This may have implications for proximal colon cancer prevention and be due to the failure of endoscopy to detect/remove SSPs, or the hypothesized rapid development of SSPs.

Concerns and challenges in flexible sigmoidoscopy screening

In 1992, two well-conducted case-control studies used data from two different health maintenance organizations and demonstrated a 59-79% reduction in mortality from colorectal cancer (CRC) following exposure to sigmoidoscopy. These studies highlight the possibility of reducing mortality from CRC using population-based endoscopic screening. The development of fiber optics improved the technology, and the ease of performing flexible sigmoidoscopy (FS) with widespread adoption of this screening modality. To date, FS is the only endoscopic screening modality that has been shown to reduce mortality in randomized clinical trials. This article reviews the development of sigmoidoscopy, its use in CRC screening and the current reduced role of this proven screening modality, and explores new frontiers for population-based FS screening.

Colonoscopy screening markedly reduces the occurrence of colon carcinomas and carcinoma-related death: a closed cohort study

BACKGROUND

Colonoscopy with a possible polypectomy is an efficient and preferred screening method to reduce the incidence of colorectal cancer (CRC). However, critics argue that, to date, a reduction of incidence and mortality from CRC has not been demonstrated in a population-based setting.

OBJECTIVE

To compare the incidence of and mortality from CRC among individuals screened by colonoscopy and non-screened individuals.

DESIGN

A closed cohort study.

SETTING

Population-based setting in a precisely defined area with a low level of population migration.

PATIENTS

This study involved 1912 screened and 20,774 control participants.

INTERVENTION

CRC cases in this closed cohort study were prospectively collected during the screening period of 1 year and the follow-up period of 6 years.

MAIN OUTCOME MEASUREMENTS

Follow-up data were corrected for negligible migration balance in the area. Tumor characteristics and risk or protective factors, age and sex, participation in general health screening examinations, history of CRC in a first-degree relative, smoking status, body mass index, frequency of sports activity, eating habits, and patients' professions were recorded.

RESULTS

Overall cancer incidence was significantly lower in the screened group compared with the non-screened group (adjusted odds ratio [OR] 0.31; 95% confidence interval [CI], 0.16-0.59; P < .001). Colon cancer-associated mortality also was clearly lower (adjusted OR 0.12; 95% CI, 0.01-0.93; P = .04). Risk factors such as lifestyle, smoking, and body mass index as well as family history were similar in both groups. Blue-collar workers had a higher incidence of CRC compared with professionals. The risk factors for CRC were a positive family history and smoking.

LIMITATIONS

Number and ethnicity of the participants, non-randomized study.

CONCLUSION

Colonoscopy with polypectomy significantly reduces CRC incidence and cancer-related mortality in the general population.

The Your Disease Risk Index for colorectal cancer is an inaccurate risk stratification tool for advanced colorectal neoplasia at screening colonoscopy

Tailoring the use of screening colonoscopy based on the risk of advanced colorectal neoplasia (ACN) could optimize the cost-effectiveness of colorectal cancer (CRC) screening. Our goal was to assess the accuracy of the Your Disease Risk (YDR) CRC risk index for stratifying average risk patients into low- versus intermediate/high-risk categories for ACN. The YDR risk assessment tool was administered to 3,317 asymptomatic average risk patients 50 to 79 years of age just before their screening colonoscopy. Associations between YDR-derived relative risk (RR) scores and ACN prevalence were examined using logistic regression and χ(2) analyses. ACN was defined as a tubular adenoma ≥1 cm, tubulovillous or villous adenoma of any size, and the presence of high-grade dysplasia or cancer. The overall prevalence of ACN was 5.6%. Although YDR-derived RR scores were linearly associated with ACN after adjusting for age and gender (P = 0.033), the index was unable to discriminate "below average" from "above/average" risk patients [OR, 1.01; 95% confidence interval (CI), 0.75-1.37]. Considerable overlap in rates of ACN was also observed between the different YDR risk categories in our age- and gender-stratified analyses. The YDR index lacks accuracy for stratifying average risk patients into low- versus intermediate/high-risk categories for ACN.

Effect of comorbid conditions on adherence to colorectal cancer screening

Potential barriers to colorectal cancer (CRC) screening include preexisting medical conditions (comorbidities), physician recommendation, psychosocial factors, and screening preparedness. This study's purpose was to investigate the impact of comorbid conditions on CRC screening among African Americans. A stage-matched randomized clinical trial was performed. Asymptomatic African Americans over age 50, with a primary care physician, and eligible for CRC screening were recruited at The Mount Sinai Hospital from 2005 to 2008. One hundred sixty-one patients were assessed for referral for, and completion of, CRC screening, comorbid conditions, "readiness to change," and number of physician visits within the observation period. Data was compared to a pretrial index to predict the likely effect of comorbid conditions on CRC screening. One hundred fifty-nine patients completed the study; 108 (68.9%) were referred for and 34 (21.2%) completed CRC screening. No demographic characteristics were associated with CRC screening completion. CRC screening referrals were similar for all patients, regardless of comorbidities or clinical visits. Comorbidities rated as having extreme influence on CRC screening showed a trend toward lower screening rates. There was a significant increase in screening rates among participants in advanced stages of readiness at enrollment. These data suggest that while comorbidities did not predict colonoscopy completion, they may play a role in concert with other factors. This is the only study to assess the effect of screening colonoscopy in an African American primary care setting. We must continue to explore interventions to narrow the disparate gap in screening and mortality rates.

Efficacy of a nationwide screening colonoscopy program for colorectal cancer

BACKGROUND & AIMS

Screening colonoscopy examinations for colorectal cancer are offered in the United States and some European countries. Data on results and adverse effects of screening colonoscopy are limited. In autumn 2002, colonoscopy was introduced as part of a nationwide cancer screening program in Germany; it was offered to the general population for individuals 55 years of age or older. We collected and analyzed data from this program.

METHODS

We performed a prospective cross-sectional study, collecting results from 2,821,392 screening colonoscopies performed at more than 2100 practices by highly qualified endoscopists in Germany from January 2003 to December 2008. Data on participation, colorectal adenoma and cancer detection, and complications were collected using standardized documentation forms. The data generated were centrally processed and evaluated.

RESULTS

The cumulative participation rate was 17.2% of eligible women and 15.5% of eligible men 55-74 years old. The adenoma detection rate (ADR) was 19.4%, with a higher rate in men (25.8% vs 16.7% in women). Advanced adenomas were found in 6.4% of patients. Carcinomas were detected in 25,893 subjects (0.9%); most were of an early UICC stage (I, 47.3%; II, 22.3%; III, 20.7%; IV, 9.6%). The ADRs for gastroenterologists and nongastroenterologists were 25.1% and 22.3%, respectively (adjusted odds ratio, 1.18; 95% confidence interval, 1.16-1.21). The overall complication rate was 2.8/1000 colonoscopies, and the rate of serious complications was 0.58/1000 colonoscopies.

CONCLUSIONS

A nationwide colonoscopy screening program that uses highly qualified endoscopists can detect a significant number of adenomas and early-stage carcinomas. The ADR for gastroenterologists was higher than for nongastroenterologists.

Screening for colorectal cancer: what fits best?

Colorectal cancer (CRC) screening has been shown to be effective in reducing CRC incidence and mortality. There are currently a number of screening modalities available for implementation into a population-based CRC screening program. Each screening method offers different strengths but also possesses its own limitations as a population-based screening strategy. We review the current evidence base for accepted CRC screening tools and evaluate their merits alongside their challenges in fulfilling their role in the detection of CRC. We also aim to provide an outlook on the demands of a low-risk population-based CRC screening program with a view to providing insight as to which modality would best suit current and future needs.

Stool DNA screening for colorectal neoplasia: biological and technical basis for high detection rates

Colorectal cancer (CRC), the second most common cause of cancer-related mortality worldwide, is preventable with effective screening and removal of precursor lesions. Yet, screening efforts have been hampered by low participation rates and by performance limitations of the screening tools themselves. Stool DNA testing has emerged as a biologically rational and user-friendly strategy for the non-invasive detection of both CRC and critical precursor lesions. Unlike most conventional screening tools, stool DNA testing detects proximal and distal colorectal neoplasms equally well. Several key technical advances have led to increasingly accurate approaches for stool DNA testing including use of a DNA preservative buffer with stool collection, efficient target capture and amplification methods, broadly informative marker panels, and automated assay components. Based on recent studies, advanced multi-marker stool DNA tests including methylated markers, mutation markers and an assessment of faecal haemoglobin have been shown to detect CRC at sensitivities of 85% and higher and adenomas >1 cm at 60% and higher in a case-control environment. If the high accuracy of multi-marker stool tests is corroborated in multicentre screening studies on average-risk persons currently underway, then these stool tests could influence our CRC screening paradigm.This review discusses the biological basis, key technical advances, and recent clinical performance validation of stool DNA testing.

Novel molecular screening approaches in colorectal cancer

Traditional methods for colorectal cancer (CRC) screening have reduced rates of malignancy and death; however, low compliance and morbidities associated with invasive techniques have encouraged efforts for establishing equally effective, less invasive novel screening approaches. We review the current state of novel screening approaches in CRC to include CT colonography, fecal DNA, DNA methylation, micro-RNA, and protein and molecular markers.

Association between bacteremia due to Streptococcus gallolyticus subsp. gallolyticus (Streptococcus bovis I) and colorectal neoplasia: a case-control study

BACKGROUND

The association between bacteremia by Streptococcus gallolyticus subsp. gallolyticus (SGG) and colorectal neoplasia (CRN) is well established but the frequency of the association varies widely in different studies. We conducted a case-control study to assess the association between SGG bacteremia and CRN.

METHODS

An analysis of all SGG bacteremias was performed during the period 1988-2011. The frequency of CRN in patients with SGG bacteremia was compared with the frequency of CRN in a symptomatic control group of patients matched at a 1:2 ratio for gender and age (±3 years) without S. bovis bacteremia and personal history of CRN and with increased risk of CRN (by the presence of symptoms, signs, or test suspicious of colonic pathology or by family history of CRN).

RESULTS

One hundred nine cases of SGG bacteremia were detected (mean age, 66 years; 87% male). Colonoscopy was performed in 98 cases, diagnosing 69 cases of CRN: 57 adenomas (39 advanced adenomas) and 12 invasive carcinomas. Only 4 cases had suspected CRN before the blood culture. The prevalence of CRN was higher in patients with SGG bacteremia than in the 196 control patients (70% vs 32%; odds ratio [OR], 5.1; 95% confidence interval [CI], 3.0-8.6). This difference was not significant when comparing nonadvanced adenomas (19% vs 12%), but we found significant differences in advanced adenomas (40% vs 16%; OR, 3.5; 95% CI, 2.0-6.1) and invasive carcinomas (12% vs 5%; OR, 2.9; 95% CI, 1.2-6.9).

CONCLUSIONS

The frequency of CRN among SGG infected patients is significantly increased compared with symptomatic age-matched controls, indicating that SGG infection is a strong indicator for underlying occult malignancy.

Transparent-cap-fitted colonoscopy shows higher performance with cecal intubation time in difficult cases

AIM: To investigate the efficacy of cap-fitted colonoscopy (CFC) with regard to cecal intubation time.

METHODS: Two hundred and ninety-five patients undergoing screening colonoscopy at Gospel Hospital, Kosin University College of Medicine were enrolled in this randomized controlled trial between January and December 2010. Colonoscopies were conducted by a single endoscopist. Patient characteristics including age, sex, body mass index, history of abdominal surgery, quality of preparation, and the presence of diverticulosis were recorded.

RESULTS: One hundred and fifty patients were allocated into a CFC group and 145 into a non-CFC (NCF) group. Cecal intubations were achieved in all patients. Cecal intubation time in the CFC group was significantly shorter than in the NCF group for specific conditions: age ≥ 60 years, prior abdominal surgery, and poor bowel preparation. The number of detected adenomas was higher in the CFC group than in the NCF group (P = 0.040).

CONCLUSION: CFC facilitated shortening of the cecal intubation time in difficult cases, and was more sensitive for detecting adenomas than was NCF.

The relationship between distal and proximal colonic neoplasia: a meta-analysis

OBJECTIVES

To investigate the association between proximal colonic neoplasia and distal lesions as a function of the lesion type. The extent to which health, demographic, and study characteristics moderate this association was also examined.

DATA SOURCES

Google Scholar, Web of Science, Scopus, and PubMed.

STUDY ELIGIBILITY CRITERIA

Studies allowing the calculation of OR of proximal neoplasia (PN) and proximal advanced neoplasia (PAN) for distal hyperplastic polyps (HP), nonadvanced adenomas (NAA), adenomas (AD), and advanced neoplasia (AN); also, studies for which the proportions of subjects with isolated (i.e., not accompanied by distal lesions) PN (IPN) and PAN (IPAN) over the total number of subjects with PN or PAN could be calculated.

STUDY APPRAISAL AND SYNTHESIS METHODS

Thirty-two studies were included for calculating OR between proximal neoplasia and distal lesions and 40 studies for proportions of IPN and IPAN. Subgroup analyses were conducted for presence of symptoms, prevalence of PN and PAN, age, proportion of males, geographic region, study design, and demarcation point.

RESULTS

The association between distal lesions and proximal neoplasia increased with the severity of the distal lesions. Odds of PN were higher in subjects with HP compared to subjects with a normal distal colon. Odds of PN and PAN were higher in subjects with NAA, AD, and AN than in subjects with a normal distal colon. PAN were more strongly associated with distal lesions in asymptomatic populations, in young populations, and in populations with a low prevalence of PAN. In approximately 60% of the subjects with PN and PAN, these neoplasia were isolated.

LIMITATIONS

The present results may be affected by publication bias and dichotomization in the subgroup analyses. Limitations related to the individual studies include self-selection, lesion misclassification and misses, and technological advances leading to changes in the detection of lesions during the time span of the included studies.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

All types of distal lesions are predictive of PN. All types of distal neoplasia are predictive of PAN. The association between distal lesions and proximal neoplasia increases with the severity of the distal lesion. The association between distal lesions and proximal advanced neoplasia is stronger in low-risk groups as compared to high-risk groups.

[The Alliance for the Prevention of Colorectal Cancer in Spain. A civil commitment to society]

Colorectal cancer (CRC) is the most common malignant tumor in Spain, when men and women are considered together, and the second leading cause of cancer death. Every week in Spain over 500 cases of CRC are diagnosed, and nearly 260 people die from the disease. Epidemiologic estimations for the coming years show a significant increase in the number of annual cases. CRC is a perfectly preventable tumor and can be cured in 90% of cases if detected in the early stages. Population-based screening programs have been shown to reduce the incidence of CRC and mortality from the disease. Unless early detection programs are established in Spain, it is estimated that in the coming years, 1 out of 20 men and 1 out of 30 women will develop CRC before the age of 75. The Alliance for the Prevention of Colorectal Cancer in Spain is an independent and non-profit organization created in 2008 that integrates patients' associations, altruistic non-governmental organizations and scientific societies. Its main objective is to raise awareness and disseminate information on the social and healthcare importance of CRC in Spain and to promote screening measures, early detection and prevention programs. Health professionals, scientific societies, healthcare institutions and civil society should be sensitized to this highly important health problem that requires the participation of all sectors of society. The early detection of CRC is an issue that affects the whole of society and therefore it is imperative for all sectors to work together.

Flexible sigmoidoscopy in the randomized prostate, lung, colorectal, and ovarian (PLCO) cancer screening trial: added yield from a second screening examination

BACKGROUND

Among randomized trials evaluating flexible sigmoidoscopy (FSG) for its effect on colorectal cancer mortality, only the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial screened its participants more than one time. We report outcomes from the PLCO screening FSG program and evaluate the increased yield produced by a second FSG.

METHODS

Participants were screened by 60-cm FSG in 10 regional screening centers at study entry and 3 or 5 years later, depending on the time of random assignment. Results from subsequent diagnostic intervention were tracked and recorded in a standardized fashion, and outcomes were compared according to sex and age. The protocol discouraged repeat FSG in persons with colorectal cancer or adenoma diagnosed after the initial FSG.

RESULTS

Of 77 447 enrollees, 67 073 (86.6%) had at least one FSG and 39 443 (50.9%) had two FSGs. Diagnostic intervention occurred in 74.9% after a positive first FSG and in 78.7% after a positive repeat FSG. The second FSG increased the screening yield by 32%: Colorectal cancer or advanced adenoma was detected in 37.8 per 1000 persons after first screening and in 49.8 per 1000 persons after all screenings. The second FSG increased the yield of cancer or advanced adenoma by 26% in women and by 34% in men. Of 223 subjects who received a diagnosis of colorectal carcinoma within 1 year of a positive FSG, 64.6% had stage I and 17.5% had stage II disease.

CONCLUSIONS

Repeat FSG increased the detection of colorectal cancer or advanced adenoma in women by one-fourth and in men by one-third. Screen-detected carcinomas were early stage (stage I or II) in greater than 80% of screened persons. Colorectal cancer mortality data from the PLCO, as the definitive endpoint, will follow in later publications.

Assessment of quality in screening colonoscopy for colorectal cancer

INTRODUCTION

The effectiveness of screening colonoscopy in decreasing the incidence of colorectal cancer (CRC) is largely dependent on the detection of polyps and the quality of the procedure. Several key quality measures have been proposed to improve the effectiveness of screening colonoscopies.

AIM

To evaluate quality indicators of screening colonoscopy in a tertiary hospital.

METHODS

All CRC screening colonoscopies performed between 2005 and 2009 in a single tertiary center were reviewed for internationally accepted quality measures.

RESULTS

Of the 1545 individuals who underwent first-time screening colonoscopy 38% were male and 62% were female. The mean age of the patients was 60.4 years and the mean difference in ages was ± 10.3 years. Cecal intubation rate was 91% (1336), however ileocecal valve photo documentation was performed in only 81% (1248) colonoscopies. The quality of bowel preparation was classified as: good 76% (1171), reasonable 11% (174), and poor 13% (200). Polyp detection rate (PDR) was 33% (503). The prevalence of polyps ≥1 cm in size was 5% (82). PDR was significantly higher in men than in women (44% [260] vs 25% [243], P = 0.0001). Other factors significantly influencing PDR were quality of bowel preparation (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 0.9-1.6) and age over 50 (OR: 1.9, 95% CI: 1.3-2.9). Left colonic polyps were associated with a risk ratio of 2.3 (95% CI: 1.8-2.9) of lesions in the other colonic segments compared to no polyps in the left colon. None of the colonoscopists reported withdrawal time.

CONCLUSION

Cecal intubation rate and quality of bowel preparation were suboptimal. The polyp detection rate compares favorably to accepted standards and its main determinants are male sex, age >50 years, quality of bowel preparation, and the presence of left colonic polyps.

Usefulness of an intensive bowel cleansing strategy for repeat colonoscopy after preparation failure

BACKGROUND

No consensus exists regarding the optimal bowel preparation regimen for patients with poor bowel cleansing at a previous colonoscopy.

OBJECTIVE

We investigated the usefulness of an intensive cleansing regimen for repeat colonoscopy after previous failure of bowel preparation.

DESIGN AND SETTING

A prospective observational study was performed in patients undergoing colonoscopy at a university-based, tertiary referral hospital.

PATIENTS AND INTERVENTION

Outpatients with inadequate preparation at an index colonoscopy were offered a repeat colonoscopy and instructed to follow an intensive preparation regimen consisting of a low-fiber diet for 72 hours, liquid diet for 24 hours, bisacodyl (10 mg) in the evening of the day before the colonoscopy, and a split dose of polyethylene glycol (1.5 L in the evening before and 1.5 L in the morning on the day of the colonoscopy).

MAIN OUTCOME MEASURES

The adequacy of bowel cleansing was assessed according to the Boston Bowel Preparation Scale (0 or 1 on any colon segment = inadequate bowel preparation). Procedural variables, detection rates for polyps and adenomas, compliance, and tolerability of the regimen were assessed. Satisfaction with the regimen was assessed with a 10-point visual analog scale.

RESULTS

Of 83 patients with inadequate bowel preparation at colonoscopy, 51 underwent a second colonoscopy and were analyzed; 46 patients (90.2%) had adequate bowel cleansing at the second colonoscopy, with a mean (SD) total Boston Bowel Preparation Scale score of 7.43 (1.5) and scores of 2.31 (0.6) for the right colon, 2.49 (0.6) for the transverse colon, and 2.63 (0.6) for the left colon. Polyps, flat lesions, or flat lesions proximal to the splenic flexure were found in significantly more patients at the second colonoscopy than at the index colonoscopy. The global satisfaction score was 6.6 (2.7).

LIMITATIONS

The study was limited because of its open observational design, possible patient learning effect for bowel preparation at the repeat colonoscopy, and the inclusion of only outpatients.

CONCLUSIONS

An intensive regimen consisting of a low-fiber diet, bisacodyl, and a split dose of polyethylene glycol can achieve good colon preparation with an improved detection rate for polyps and adenomas in most patients who have had poor bowel cleansing at a previous colonoscopy.

Short term outcome of patients with hematochezia and normal initial colonoscopic findings: do they really need further screening?

BACKGROUND

In a significant number of the patients with hematochezia, colonoscopy turns out to be normal and therefore is unable to determine the cause of bleeding. This study investigates outcomes and possible necessity for further work up in cases of hematochezia with normal colonoscopy.

METHODS

Ninety-seven patients with normal colonoscopy were followed for at least one year from the time of colonoscopy by regular visits and phone calls. Mortality and recurrent bleeding were recorded as primary end points. Those with recurrent or continued hematochezia were invited for a new visit and further work up.

RESULTS

Among the ninety seven patients, nine cases (9.3%) were lost at follow ups, 10 experienced rebleeding (10.3 %), and the remaining 78 (80.4 %) were apparently healthy and had no further complaints. There were two mortalities during the follow up, one due to gastric cancer and the other due to cerebrovascular accident.

CONCLUSION

It is unusual for the cases of hematochezia with a normal initial colonoscopy to have recurrent bleeding as a result of a significant missed lesion in the colon.

Test performance of immunologic fecal occult blood testing and sigmoidoscopy compared with primary colonoscopy screening for colorectal advanced adenomas

Given the current increase in colorectal cancer screening, information on performance of screening tests is needed, especially in groups with a presumed lower test performance. We compared test performance of immunologic fecal occult blood testing (FIT) and pseudosigmoidoscopy with colonoscopy for detection of advanced adenomas in an average risk screening population. In addition, we explored the influence of gender, age, and location on test performance. FIT was collected prior to colonoscopy with a 50 ng/mL cutoff point. FIT results and complete colonoscopy findings were available from 329 subjects (mean age: 54.6 ± 3.7 years, 58.4% women). Advanced adenomas were detected in 38 (11.6%) of 329 subjects. Sensitivity for advanced adenomas of FIT and sigmoidoscopy were 15.8% (95% CI: 6.0-31.3) and 73.7% (95% CI: 56.9-86.6), respectively. No sensitivity improvement was obtained using the combination of sigmoidoscopy and FIT. Mean fecal hemoglobin in FIT positives was significantly lower for participants with only proximal adenomas versus those with distal ones (P = 0.008), for women versus men (P = 0.023), and for younger (<55 years) versus older (≥55 years) subjects (P = 0.029). Sensitivities of FIT were 0.0% (95% CI: 0.0-30.9) in subjects with only proximal versus 21.4% (95% CI: 8.3-41.0) in those with distal nonadvanced adenomas; 5.3% (95% CI: 0.0-26.0) in women versus 26.3% (95% CI: 9.2-51.2) in men; 9.5% (95% CI: 1.2-30.4) in younger versus 23.5% (95% CI: 6.8-49.9) in older subjects. Sigmoidoscopy had a significantly higher sensitivity for advanced adenomas than FIT. A single FIT showed very low sensitivity, especially in subjects with only proximal nonadvanced adenomas, in women, and in younger subjects. This points to the existence of "low" FIT performance in subgroups and the need for more tailored screening strategies.

Epidemiological study of colorectal adenoma and cancer in symptomatic patients in China between 1990 and 2009

OBJECTIVE

The best cure for colorectal cancer (CRC) lies on its early diagnosis and treatment. We aimed to provide the epidemiological features of advanced colorectal adenoma (A-CRA) and CRC in symptomatic patients and to determine whether the incidences of A-CRA and CRC increased simultaneously in China between 1990 and 2009.

METHODS

A total of 157,943 patients who had undergone a colonoscopy from 1990 to 2009 were enrolled, of which 6,777 patients had A-CRA and 3,503 had CRC. They were compared with controls in a stratified analysis. The detection rates of A-CRA and CRC in the 1990s and 2000s were also compared.

RESULTS

The detection rate of A-CRA increased 1.88-fold over the two decades, while that of CRC increased 0.66-fold. The percentages of patients with A-CRA and CRC who were elder than 50 years were significantly higher in the 2000s than those in the 1990s (P = 0.000). The changes of location of A-CRA and CRC during the two decades indicated a shift of lesions from the distal colon to proximal colon.

CONCLUSION

There was a significant increase in detection rate of A-CRA in the 2000s, but CRC did not increase at a similar speed. Our results indicated that the early detection and removal of colorectal adenoma in symptomatic patients might decrease the incidence of CRC.

Recommendations for post-polypectomy surveillance in community practice

BACKGROUND

After colon cancer screening, large numbers of persons discovered with colon polyps may receive post-polypectomy surveillance with multiple colonoscopy examinations over time. Decisions about surveillance interval are based in part on polyp size, histology, and number.

AIMS

To learn physicians' recommendations for post-polypectomy surveillance from physicians' office charts.

METHODS

Among 322 physicians performing colonoscopy in 126 practices in N. Carolina, offices of 152 physicians in 55 practices were visited to extract chart data, for each physician, on 125 consecutive persons having colonoscopy in 2003. Subjects included persons with first-time colonoscopy and no positive family history or other indication beyond colonoscopy findings that might affect post-polypectomy surveillance recommendations. Data were extracted about demographics, reason for colonoscopy, family history, symptoms, bowel prep, extent of examination, and features of each polyp including location, size, histology. Recommendations for post-polypectomy surveillance were noted.

RESULTS

Among 10,089 first-time colonoscopy examinations, hyperplastic polyps were found in 4.5% of subjects, in whom follow-up by 4-6 years was recommended in 24%, sooner than recommended in guidelines. Of the 6.6% of persons with only small adenomas, 35% were recommended to return in 1-3 years (sooner than recommended in some guidelines) and 77% by 6 years. Surveillance interval tended to be shorter if colon prep was less than "excellent." Prep quality was not reported for 32% of examinations.

CONCLUSIONS

Surveillance intervals after polypectomy of low-risk polyps may be more aggressive than guidelines recommend. The quality of post-polypectomy surveillance might be improved by increased attention to guidelines, bowel prep, and reporting.

Once-only sigmoidoscopy in colorectal cancer screening: follow-up findings of the Italian Randomized Controlled Trial--SCORE

BACKGROUND

A single flexible sigmoidoscopy at around the age of 60 years has been proposed as an effective strategy for colorectal cancer (CRC) screening.

METHODS

We conducted a randomized controlled trial to evaluate the effect of flexible sigmoidoscopy screening on CRC incidence and mortality. A questionnaire to assess the eligibility and interest in screening was mailed to 236,568 men and women, aged 55-64 years, who were randomly selected from six trial centers in Italy. Of the 56,532 respondents, interested and eligible subjects were randomly assigned to the intervention group (invitation for flexible sigmoidoscopy; n = 17,148) or the control group (no further contact; n = 17,144), between June 14, 1995, and May 10, 1999. Flexible sigmoidoscopy was performed on 9911 subjects. Intention-to-treat and per-protocol analyses were performed to compare the CRC incidence and mortality rates in the intervention and control groups. Per-protocol analysis was adjusted for noncompliance.

RESULTS

A total of 34,272 subjects (17,136 in each group) were included in the follow-up analysis. The median follow-up period was 10.5 years for incidence and 11.4 years for mortality; 251 subjects were diagnosed with CRC in the intervention group and 306 in the control group. Overall incidence rates in the intervention and control groups were 144.11 and 176.43, respectively, per 100,000 person-years. CRC-related death was noted in 65 subjects in the intervention group and 83 subjects in the control group. Mortality rates in the intervention and control groups were 34.66 and 44.45, respectively, per 100,000 person-years. In the intention-to-treat analysis, the rate of CRC incidence was statistically significantly reduced in the intervention group by 18% (rate ratio [RR] = 0.82, 95% confidence interval [CI] = 0.69 to 0.96), and the mortality rate was non-statistically significantly reduced by 22% (RR = 0.78; 95% CI = 0.56 to 1.08) compared with the control group. In the per-protocol analysis, both CRC incidence and mortality rates were statistically significantly reduced among the screened subjects; CRC incidence was reduced by 31% (RR = 0.69; 95% CI = 0.56 to 0.86) and mortality was reduced by 38% (RR = 0.62; 95% CI = 0.40 to 0.96) compared with the control group.

CONCLUSION

A single flexible sigmoidoscopy screening between ages 55 and 64 years was associated with a substantial reduction of CRC incidence and mortality.

Prevalence of advanced adenomas in small and diminutive colon polyps using direct measurement of size

BACKGROUND AND AIMS

Most studies reporting polyp size use visual estimates. Determining the prevalence of advanced histology based on direct measurement of polyp size may help guide the management of polyps found at optical colonoscopy (OC) and CT colonography (CTC).

METHODS

We designed a large, prospective study to assess the prevalence of advanced adenomas based on direct measurement of polyp size by a certified pathologists' assistant as reported in the pathology report. Patients between 40 and 89 years of age who presented for screening colonoscopy were included in our study. Advanced adenomas were defined as ≥10 mm or ≥25% villous features, high grade dysplasia or cancer. Polyps were divided by size into three groups: diminutive (≤5 mm), small (6-9 mm) and large (≥10 mm). If more than one adenoma was present, the most advanced was used for analysis.

RESULTS

We evaluated 6,905 consecutive patients referred for colonoscopy between January 2005 and December 2006. Of the 4,967 who met the inclusion criteria, the mean age was 58.8 and consisted of 59% women. Overall, 930 (18.7%) had an adenoma; 248 (5%) were advanced adenomas including 8 (0.16%) cancers. Of 89 polyps≥10 mm, 76 (85%) had advanced histology; of 247 polyps 6-9 mm, 67 (27%) were advanced; of 1,025 polyps ≤5 mm, 105 (10%) were advanced. Thus, 172 of 248 (69%) patients with advanced adenomas had small or diminutive adenomas.

CONCLUSIONS

Our data indicate the majority (69%) of advanced adenomas are <10 mm. Even among polyps≤5 mm, there was an appreciable prevalence of advanced adenomas (10%). These findings may help guide the management of sub-centimeter colon polyps found by OC or CTC.

Push enteroscopy has a 96% cecal intubation rate in colonoscopies that failed because of redundant colons

BACKGROUND

Performing a complete colonoscopy to the cecum is important for ruling out malignancy and other lesions, but failure rates are significant with a standard colonoscope. A previous study using a push enteroscope for failed colonoscopies had a completion rate of 68.7%.

OBJECTIVE

To improve the cecal intubation rate by using a newer version of a push enteroscope.

DESIGN

Retrospective study at first, then a prospective study.

SETTING

Single-center veterans health care system.

PATIENTS

A total of 47 patients in whom the cecum was not reached with a regular adult colonoscope between January 2007 and December 2010 were included. Those with poor bowel preparation were excluded.

INTERVENTIONS

Repeat colonoscopy using a new version of a push enteroscope.

MAIN OUTCOME MEASUREMENTS

The rate of cecal intubation and additional pathological findings.

RESULTS

The cecum or terminal ileum was reached in 45 patients (96%). Additional significant pathological findings in the previously unexamined colon were seen in 18 patients (38%).

LIMITATIONS

Small sample size, lack of comparison with other endoscopes.

CONCLUSIONS

Colonoscopy with a push enteroscope could be advanced to either the terminal ileum or cecum in 96% of patients, which is one of the highest known completion rates in patients in whom colonoscopy failed. Clinical management changed in all patients with additional findings.

Colorectal cancer screening

Colorectal cancer (CRC) is the third most common cause of cancer death worldwide and a major health problem. In this review, the different approaches for CRC screening will be outlined with emphasis on evidence-based medicine. Evidence from randomized trials on the effectiveness of CRC screening is summarized. Several screening tools for CRC are available. They can be categorized according to their mode of action: early detection tools such as the faecal occult blood test (FOBT) and cancer prevention tools such as flexible sigmoidoscopy and colonoscopy. Meta-analyses of randomized trials show that FOBT screening reduces CRC mortality by 16% (risk ratio 0.84; 95% confidence interval (CI) 0.78-0.9) compared with 30% (risk ratio 0.7; 95% CI 0.6-0.81) for flexible sigmoidoscopy screening. FOBT screening is cheap and noninvasive, but results in large numbers of false-positive tests and needs to be repeated frequently. Flexible sigmoidoscopy is more invasive, but is effective for once-only screening. Although colonoscopy screening is used in some countries, no randomized trials have been conducted to estimate its benefit, and therefore, it should not be recommended at the present time. Faecal occult blood test and flexible sigmoidoscopy are the two CRC screening tools that can be recommended as they have been proven to reduce CRC mortality. Colonoscopy has the potential to be superior to FOBT and flexible sigmoidoscopy, but needs to be evaluated in randomized trials before any recommendation can be provided.

Colorectal cancer screening and prevention in women

Colorectal cancer (CRC) is the third most common cause of cancer in women. Screening for CRC increases early detection of cancer and premalignant polyps and decreases morbidity from this disease. However, adherence to the screening guidelines continues to remain inadequate both at the physician and patient levels. Several factors are of special importance to women. Presence of prior gynecological malignancies may increase the risk of CRC in women. Furthermore, new studies have shown other factors such as obesity and smoking to increase the risk of CRC in women. This article highlights issues unique to women with regards to CRC and outlines special considerations for determining screening intervals in women, identifies factors that make screening more difficult in women, and reviews studies that identify preventative strategies which, together with screening, may reduce the burden of CRC.

Screening for colorectal carcinoma

Colorectal carcinoma is the second most common cause of death in Canada. Because there is a precursor lesion (that is, the polyp), screening is critically important to prevent the disease through polyp removal-and failing that, to detect colorectal carcinoma at an early stage, when it can be cured. Several screening modalities are available, but colonoscopy is considered the best. People should avail themselves of such examinations, and physicians should encourage them to do so.

Risk of proximal colonic neoplasms in asymptomatic adults older than 50 years found to have distal hyperplastic polyps on routine colorectal cancer screening

PURPOSE

A retrospective case-control study was conducted to evaluate whether hyperplastic polyps (HPs) found in the lower 50 cm of colon could be used as indicators for synchronous proximal neoplasms (SPNs) in the large intestine. Additionally, other characteristics considered included age; sex; ethnicity; history of cancer, cholecystectomy, or appendectomy; current use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs); current use of estrogen or hormone replacement therapy (HRT) in women; current smoking status; and the size, number, and location of the distal HP if present.

METHODS

Convenience sampling of medical charts and colonoscopy reports compiled during a ten-year period was used to glean the sample of 1792 participants.

RESULTS

Distal HPs in the lower 50 cm of colon were not significantly associated with SPN when patients with HPs were compared with those without any distal polyps at all (odds ratio [OR] = 0.94; 95% confidence interval [CI] = 0.73-1.22). However, significant relationships with proximal neoplasms (adenomas, advanced adenomas, and colon cancer) were noted in patients with a prior diagnosis of cancer (OR = 1.62; 95% CI =1.25-2.11), advancing age (OR = 1.02; 95% CI = 1.01-1.03), non-Caucasian (men only) ethnicity (OR = 0.72; 95% CI = 0.55-0.96), a history (men only) of taking aspirin or NSAIDs (OR = 0.73; 95% CI = 0.56-0.95), and a history (women only) of taking estrogen or receiving HRT (OR = 1.51; 95% CI = 1.04-2.20).

CONCLUSION

Routinely recommending a colonoscopy for every patient with distal HPs found only by screening flexible sigmoidoscopy is neither justified nor necessary. Nevertheless, further investigation (ie, colonoscopy) may be warranted in the aforementioned subgroups.

Screening options and recommendations for colorectal cancer

Screening reduces the burden of disease from colorectal cancer through early detection of cancerous lesions and removal of precancerous polyps. The ideal colorectal cancer screening modality should be cost-effective, increase life-years gained, permit long intervals between tests with high patient compliance and low risk to the patient. Although no single colorectal cancer screening method is perfect, several options exist. Government agencies and medical societies have published screening recommendations with differing guidelines; yet, despite the lack of a consistent standard, it is clear that colorectal cancer screening is cost-effective. In this review, the authors address several options for screening, identify risks and benefits, and present methods to risk stratify patients. A thorough discussion with the patient about potential benefits and harms is critical before initiating any screening regimen.

Biomarkers related to one-carbon metabolism as potential risk factors for distal colorectal adenomas

BACKGROUND

Efficient one-carbon metabolism, which requires adequate supply of methyl group donors and B-vitamins, may protect against colorectal carcinogenesis. However, plasma folate and vitamins B2 and B12 have inconsistently been associated with colorectal cancer risk, and there have been no previous studies relating plasma concentrations of methionine, choline, and betaine to this outcome.

METHODS

This study comprised 10,601 individuals, 50 to 64 years of age, participating in the Norwegian Colorectal Cancer Prevention (NORCCAP) screening study. Using logistic regression analyses, we crosssectionally investigated associations between distal colorectal adenoma occurrence-potential precursor lesions of colorectal carcinomas-and plasma concentrations of methyl group donors and B-vitamins, and polymorphisms of genes related to one-carbon metabolism.

RESULTS

Screening revealed 1,809 subjects (17.1%) with at least one adenoma. The occurrence of high-risk adenomas (observed in 421 subjects) was inversely associated with plasma concentrations of methionine (highest versus lowest quartile: odds ratio (OR) = 0.61; 95% confidence interval (CI) = 0.45-0.83), betaine: OR = 0.74; 95% CI = 0.54-1.02, the vitamin B2 form flavin-mononucleotide (FMN): OR = 0.65; 95% CI = 0.49-0.88, and the vitamin B6 form pyridoxal 5'-phosphate (PLP): OR = 0.69; 95% CI = 0.51-0.95, but not with folate, choline, vitamin B12 concentrations, or with the studied polymorphisms. High methionine concentration in combination with high vitamin B2 or B6 concentrations was associated with lower occurrence of high-risk adenomas compared with these factors individually.

CONCLUSIONS

High plasma concentrations of methionine and betaine, and vitamins B2 and B6 may reduce risk of developing colorectal adenomas.

IMPACT

In addition to B-vitamins, methyl group donors such as methionine and betaine may play a role in colorectal carcinogenesis.

Performance of a risk index for advanced proximal colorectal neoplasia among a racially/ethnically diverse patient population (risk index for advanced proximal neoplasia)

OBJECTIVES

Tailoring the use of screening colonoscopy based on the risk of advanced proximal neoplasia (APN) has been advocated as a strategy for reducing demand and optimizing effectiveness. A 7-point index based on age, sex, and distal findings at sigmoidoscopy has been proposed that stratifies individuals into low, intermediate, and high-risk categories. The aim of this cross-sectional analysis was to determine the validity of this index, which was originally derived and validated among mostly whites, for black and Hispanic patients.

METHODS

Data, including age, sex, colonoscopic findings, and pathology, were collected retrospectively from 1,481 white, 1,329 black, and 689 Hispanic asymptomatic, average-risk patients undergoing screening colonoscopy between 2000 and 2005. Cumulative scores ranging from 0 to 7 were derived for each subject and categorized as low, intermediate, or high risk. Rates of APN were assessed for each risk category after stratification by race/ethnicity. Index performance was assessed using the C-statistic and compared across the three racial groups.

RESULTS

Rates of APN among patients categorized as low, intermediate, or high risk increased from 1.0 to 2.8 to 3.7% for whites, 1.0 to 2.2 to 4.2% for blacks, and 0.6 to 1.9 to 3.7% for Hispanics. The index performed similarly for all three groups, but showed limited ability to discriminate low from intermediate-risk patients, with C-statistic values of 0.62 for whites, 0.63 for blacks, and 0.68 for Hispanics.

CONCLUSIONS

A risk index based on age, sex, and distal endoscopic findings has limited ability to discriminate low from intermediate-risk white, black, and Hispanic patients for APN.

Effectiveness of a colonoscopic screening programme in first-degree relatives of patients with colorectal cancer

AIM

The study aimed to assess the diagnostic yield of a colonoscopy screening programme in first-degree relatives of colorectal cancer (CRC) patients and to identify factors associated with advanced neoplasia.

METHOD

We conducted a cross-sectional study. Individual characteristics, family trees and colonoscopy findings of asymptomatic first-degree relatives of CRC patients were collected. The findings were classified into cancer (invasive carcinoma and/or non-invasive high-grade neoplasia), high-risk adenomas (≥ 10 mm and/or a villous component) and low-risk adenomas (tubular < 10 mm). The dependent variable was the presence of advanced neoplasia, defined as cancer and/or high-risk adenoma.

RESULTS

Two hundred and sixty-three relatives (147 females), 50.0 ± 11.5 (range, 25-75) years of age, agreed to participate out of a total of 618 who were invited (acceptance rate 42.5%). Index cases were diagnosed at 63.8 ± 12.4 (range, 37-88) years of age. The closest familial relationship was parent/offspring in 168 (63.9%) participants and sibling in 95 (36.1%) participants; 14.8% had three or more relatives with CRC/cancer associated with Lynch syndrome, and two or more affected generations were identified in 24.0%. Advanced neoplasia was found in 56 (21.3%) participants. Of these, invasive cancer, non-invasive high-grade neoplasia and high-risk adenomas were detected in five (1.9%), six (2.3%) and 45 (17.1%) participants, respectively. Low-risk adenomas were detected in 20 (7.6%) participants. Male sex (odds ratio, 2.59; P = 0.003) and sibling relationship (odds ratio, 2.74; P = 0.001) were independently associated with advanced neoplasia.

CONCLUSION

We detected advanced neoplasia in a considerable number of participants. Our data support colonoscopy screening in first-degree relatives of patients with CRC at an earlier age than in the medium-risk population. Male sex and sibling relationship were predictors of advanced neoplasia.

Risk of advanced colorectal neoplasia according to age and gender

Background

Colorectal cancer (CRC) is one of the leading causes of cancer related morbidity and death. Despite the fact that the mean age at diagnosis of CRC is lower in men, screening by colonoscopy or fecal occult blood test (FOBT) is initiated at same age in both genders. The prevalence of the common CRC precursor lesion, advanced adenoma, is well documented only in the screening population. The purpose of this study was to assess the risk of advanced adenoma at ages below screening age.

Methods and Findings

We analyzed data from a census of 625,918 outpatient colonoscopies performed in adults in Bavaria between 2006 and 2008. A logistic regression model to determine gender- and age-specific risk of advanced neoplasia was developed. Advanced neoplasia was found in 16,740 women (4.6%) and 22,684 men (8.6%). Male sex was associated with an overall increased risk of advanced neoplasia (odds ratio 1.95; 95% confidence interval, CI, 1.91 to 2.00). At any age and in any indication group, more colonoscopies were needed in women than in men to detect advanced adenoma or cancer. At age 75 14.8 (95% CI, 14.4–15.2) screening, 18.2 (95% CI, 17.7–18.7) diagnostic, and 7.9 (95% CI, 7.6–8.2) colonoscopies to follow up on a positive FOBT (FOBT colonoscopies) were needed to find advanced adenoma in women. At age 50 39.0 (95% CI, 38.0–40.0) diagnostic, and 16.3 (95% CI, 15.7–16.9) FOBT colonoscopies were needed. Comparable numbers were reached 20 and 10 years earlier in men than in women, respectively.

Conclusions

At any age and independent of the indication for colonoscopy, men are at higher risk of having advanced neoplasia diagnosed upon colonoscopy than women. This suggests that starting screening earlier in life in men than in women might result in a relevant increase in the detection of asymptomatic preneoplastic and neoplastic colonic lesions.