Prevalence of adenomas and colorectal cancer in average risk individuals: a systematic review and meta-analysis

Frequency of colonic adenomatous polyps in a tertiary hospital in Mumbai

INTRODUCTION

Incidence of colorectal carcinoma is increasing all over world. There is limited data on colorectal polyps from India. We evaluated the histomorphological features of colorectal polyps and determined risk stratification in adenomatous polyps.

METHODS

In 4970 consecutive colonoscopies, colorectal polyps were detected in 515 cases (10.3 %). Polyps were classified using standard histological criteria. Each polyp was evaluated for presence of dysplasia. Adenomatous polyps were classified as low-risk adenomas (1-2 tubular adenomas <10 mm) and high-risk adenomas characterized by villous histology, high-grade dysplasia, size ≥10 mm, or ≥3 adenomas.

RESULTS

Of 515 colorectal polyps, 270 (52.4 %) were adenomatous, followed by 78 (15.1 %) inflammatory, 78 (15.1 %) hyperplastic, 32 (6.2 %) hamartomatous polyps, 25 (4.8 %) benign epithelial polyps, 5 (0.9 %) cap polyps, 5 (0.9 %) lipomatous polyps, 3 (0.5 %) angiomatous polyps, 4 (0.7 %) lymphoid, and 15 (2.9 %) cases with adenocarcinoma masquerading as polyps. Mean (SD) age with colorectal polyps was 54.8 (33.0) years while for adenomatous polyps, 59.5 (14.8) years with male to female ratio of 2:1. Majority of adenomatous polyps 124 (45.9 %) were tubular adenomas present in rectosigmoid. High-grade dysplasia was found in 38 (14 %) adenomas. One hundred and fifty-five (57.4 %) were high risk of which majority were villous adenomas and nine (7.2 %) tubular adenomas.

CONCLUSION

The most common colorectal polyps found during routine colonoscopy were 270 adenomatous (52.4 %) cases. Of these, 155 (57.4 %) adenomatous polyps were high-risk category. Population prevalence data of colonic polyps in general population beyond the age of 50 years needs to be obtained.

Risk of Metachronous Advanced Neoplastic Lesions in Patients with Sporadic Sessile Serrated Adenomas Undergoing Colonoscopic Surveillance

OBJECTIVES

The risk of developing metachronous advanced neoplastic lesions (ANLs) during surveillance after resection of sessile serrated adenomas (SSAs) has not been quantified.

METHODS

Patients with sporadic SSAs resected between 1 April 2007 and 31 December 2009 who underwent surveillance colonoscopy in our institution were prospectively evaluated. Patients with low-risk adenomas (LRAs), high-risk adenomas (HRAs), and negative index colonoscopy (NIC) during the same period were identified using the pathology database and electronic medical records, and were also included as a comparison cohort. The primary outcome was the comparison of the study groups with regard to incidence of metachronous ANLs during surveillance colonoscopy.

RESULTS

A total of 185 patients had SSAs, of whom 75 with 101 resected polyps were finally included. The comparison cohort consisted of 564 patients: 140 LRAs (160 polyps), 87 HRAs (478 polyps), and 337 NICs. The overall mean colonoscopy follow-up was for 54.5 months (±s.d. 14). SSA patients with synchronous HRA on index colonoscopy presented a higher incidence rate of metachronous ANL (12.96 per 1,000 person-months) compared with patients with HRA (5.07 per 1,000 person-months), whereas those with synchronous LRA and without synchronous adenoma on index colonoscopy presented a low incidence rate of metachronous ANL (0 and 1.41 per 1,000 person-months, respectively) similar to LRA (1.47 per 1,000 person-months). Among patients with SSA the 3- and 5-year ANL free-cumulative probability was 64.3 and 32.1% in those with synchronous HRA, 100 and 100% in those with synchronous LRA, and 95.1 and 91.7% if no synchronous adenoma was found.

CONCLUSIONS

Among patients with resected sporadic SSAs the risk of developing metachronous ANL is influenced by the presence of synchronous HRA on index colonoscopy. Patients with SSAs and synchronous HRA on index colonoscopy require closer surveillance, whereas those with synchronous LRA and those without synchronous adenomas may be followed up in the same way as those with LRAs.

Diagnostic colonoscopy following a positive fecal occult blood test in community health center patients

PURPOSE

Fecal occult blood testing (FOBT) is a pragmatic screening option for many community health centers (CHCs), but FOBT screening programs will not reduce mortality if patients with positive results do not undergo diagnostic colonoscopy (DC). This study was conducted to investigate DC completion among CHC patients.

METHODS

This retrospective cohort study used data from three CHCs in the Midwest and Southwest. The primary study outcome was DC completion within 6 months of positive FOBT among adults age 50-75. Patient data was collected using automated electronic queries. Manual chart reviews were conducted if queries produced no evidence of DC. Poisson regression models described adjusted relative risks (RRs) of DC completion.

RESULTS

The study included 308 patients; 63.3 % were female, 48.7 % were Spanish speakers and 35.7 % were uninsured. Based on combined query and chart review findings, 51.5 % completed DC. Spanish speakers were more likely than English speakers to complete DC [RR 1.19; 95 % confidence interval (CI) 1.04-1.36; P = 0.009], and DC completion was lower among patients with 0 visits than those with 1-2 visits (RR 2.81; 95% CI 1.83-4.33; P < 0.001) or ≥3 visits (RR 3.06; 95% CI 1.57-5.95; P = 0.001).

CONCLUSIONS

DC completion was low overall, which raises concerns about whether FOBT can reduce CRC mortality in practice. Further research is needed to understand whether CHC navigator programs can achieve very high DC rates. If organizations use FOBT as their primary CRC screening approach and a substantial number of patients receive positive results, both screening rates and DC rates should be measured.

Predicting advanced neoplasia at colonoscopy in a diverse population with the National Cancer Institute colorectal cancer risk-assessment tool

BACKGROUND

Tailoring screening to colorectal cancer (CRC) risk could improve screening effectiveness. Most CRCs arise from advanced neoplasia (AN) that dwells for years. To date, no available colorectal neoplasia risk score has been validated externally in a diverse population. The authors explored whether the National Cancer Institute (NCI) CRC risk-assessment tool, which was developed to predict future CRC risk, could predict current AN prevalence in a diverse population, thereby allowing its use in risk stratification for screening.

METHODS

This was a prospective examination of the relation between predicted 10-year CRC risk and the prevalence of AN, defined as advanced or multiple (≥3 adenomatous, ≥5 serrated) adenomatous or sessile serrated polyps, in individuals undergoing screening colonoscopy.

RESULTS

Among 509 screenees (50% women; median age, 58 years; 61% white, 5% black, 10% Hispanic, and 24% Asian), 58 (11%) had AN. The prevalence of AN increased progressively from 6% in the lowest risk-score quintile to 17% in the highest risk-score quintile (P = .002). Risk-score distributions in individuals with versus without AN differed significantly (median, 1.38 [0.90-1.87] vs 1.02 [0.62-1.57], respectively; P = .003), with substantial overlap. The discriminatory accuracy of the tool was modest, with areas under the curve of 0.61 (95% confidence interval [CI], 0.54-0.69) overall, 0.59 (95% CI, 0.49-0.70) for women, and 0.63 (95% CI, 0.53-0.73) for men. The results did not change substantively when the analysis was restricted to adenomatous lesions or to screening procedures without any additional incidental indication.

CONCLUSIONS

The NCI CRC risk-assessment tool displays modest discriminatory accuracy in predicting AN at screening colonoscopy in a diverse population. This tool may aid shared decision-making in clinical practice. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2663-2670. © 2016 American Cancer Society.

Development and Clinical Validation of a Blood Test Based on 29-Gene Expression for Early Detection of Colorectal Cancer

PURPOSE

A blood test for early detection of colorectal cancer is a valuable tool for testing asymptomatic individuals and reducing colorectal cancer-related mortality. The objective of this study was to develop and validate a novel blood test able to differentiate patients with colorectal cancer and adenomatous polyps (AP) from individuals with a negative colonoscopy.

EXPERIMENTAL DESIGN

A case-control, multicenter clinical study was designed to collect blood samples from patients referred for colonoscopy or surgery. Predictive algorithms were developed on 75 controls, 61 large AP (LAP) ≥1 cm, and 45 colorectal cancer cases and independently validated on 74 controls, 42 LAP, and 52 colorectal cancer cases (23 stages I-II) as well as on 245 cases including other colorectal findings and diseases other than colorectal cancer. The test is based on a 29-gene panel expressed in peripheral blood mononuclear cells alone or in combination with established plasma tumor markers.

RESULTS

The 29-gene algorithm detected colorectal cancer and LAP with a sensitivity of 79.5% and 55.4%, respectively, with 90.0% specificity. Combination with the protein tumor markers carcinoembryonic antigen (CEA) and CYFRA21-2 resulted in a specificity increase (92.2%) with a sensitivity for colorectal cancer and LAP detection of 78.1% and 52.3%, respectively.

CONCLUSIONS

We report the validation of a novel blood test, Colox®, for the detection of colorectal cancer and LAP based on a 29-gene panel and the CEA and CYFRA21-1 plasma biomarkers. The performance and convenience of this routine blood test provide physicians a useful tool to test average-risk individuals unwilling to undergo upfront colonoscopy. Clin Cancer Res; 22(18); 4604-11. ©2016 AACR.

Different risk factors for advanced colorectal neoplasm in young adults

AIM: To compare the risk of developing advanced colorectal neoplasm (ACRN) according to age in Koreans.

METHODS: A total of 70428 Koreans from an occupational cohort who underwent a colonoscopy between 2003 and 2012 at Kangbuk Samsung Hospital were retrospectively selected. We evaluated and compared odds ratios (OR) for ACRN between the young-adults (YA < 50 years) and in the older-adults (OA ≥ 50 years). ACRN was defined as an adenoma ≥ 10 mm in diameter, adenoma with any component of villous histology, high-grade dysplasia, or invasive cancer.

RESULTS: In the YA group, age (OR = 1.08, 95%CI: 1.06-1.09), male sex (OR = 1.26, 95%CI: 1.02-1.55), current smoking (OR = 1.37, 95%CI: 1.15-1.63), family history of colorectal cancer (OR = 1.46, 95%CI: 1.01-2.10), diabetes mellitus related factors (OR = 1.27, 95%CI: 1.06-1.54), obesity (OR = 1.23, 95%CI: 1.03-1.47), CEA (OR = 1.04, 95%CI: 1.01-1.09) and low-density lipoprotein-cholesterol (OR = 1.01, 95%CI: 1.01-1.02) were related with an increased risk of ACRN. However, age (OR = 1.08, 95%CI: 1.06-1.09), male sex (OR = 2.12, 95%CI: 1.68-2.68), current smoking (OR = 1.38, 95%CI: 1.12-1.71), obesity (OR = 1.34, 95%CI: 1.09-1.65) and CEA (OR = 1.05, 95%CI: 1.01-1.09) also increased the risk of ACRN in the OA group.

CONCLUSION: The risks of ACRN differed based on age group. Different colonoscopic screening strategies are appropriate for particular subjects with risk factors for ACRN, even in subjects younger than 50 years.

Microbiota-based model improves the sensitivity of fecal immunochemical test for detecting colonic lesions

BACKGROUND

Colorectal cancer (CRC) is the second leading cause of death among cancers in the United States. Although individuals diagnosed early have a greater than 90% chance of survival, more than one-third of individuals do not adhere to screening recommendations partly because the standard diagnostics, colonoscopy and sigmoidoscopy, are expensive and invasive. Thus, there is a great need to improve the sensitivity of non-invasive tests to detect early stage cancers and adenomas. Numerous studies have identified shifts in the composition of the gut microbiota associated with the progression of CRC, suggesting that the gut microbiota may represent a reservoir of biomarkers that would complement existing non-invasive methods such as the widely used fecal immunochemical test (FIT).

METHODS

We sequenced the 16S rRNA genes from the stool samples of 490 patients. We used the relative abundances of the bacterial populations within each sample to develop a random forest classification model that detects colonic lesions using the relative abundance of gut microbiota and the concentration of hemoglobin in stool.

RESULTS

The microbiota-based random forest model detected 91.7% of cancers and 45.5% of adenomas while FIT alone detected 75.0% and 15.7%, respectively. Of the colonic lesions missed by FIT, the model detected 70.0% of cancers and 37.7% of adenomas. We confirmed known associations of Porphyromonas assaccharolytica, Peptostreptococcus stomatis, Parvimonas micra, and Fusobacterium nucleatum with CRC. Yet, we found that the loss of potentially beneficial organisms, such as members of the Lachnospiraceae, was more predictive for identifying patients with adenomas when used in combination with FIT.

CONCLUSIONS

These findings demonstrate the potential for microbiota analysis to complement existing screening methods to improve detection of colonic lesions.

Colorectal cancer screening by colonoscopy: putting it into perspective

Implementation of nationwide screening programs aims to decrease the disease burden of colorectal cancer (CRC) in the general population. Globally, most population screening programs for CRC are carried out by either fecal occult blood test, flexible sigmoidoscopy or colonoscopy. For screening programs with colonoscopy as the primary method, only circumstantial evidence from observational studies is available to prove its effectiveness, suggesting that colonoscopy effectively reduces CRC incidence and mortality. Currently, large randomized trials are being conducted to corroborate these findings. Besides the direct effect of a screening program for CRC, its protective effect is further enhanced by enrolment of patients that underwent polypectomy in surveillance programs. However, despite CRC screening and surveillance colonoscopies, interval CRC still occur. Those are predominantly located in the right-sided colon and potential explanations, besides unfavorable tumor characteristics, are preventable operator-dependent factors relating to the quality of the colonoscopy procedure. In an effort to reduce differences in endoscopists' performance and thereby the occurrence of interval CRC, quality indicators of colonoscopy have been introduced. In addition, emerging advanced colonoscopy techniques might contribute to improvement in polyp detection and removal. Meticulous inspection of the colonic mucosa not only results in the detection of advanced and relevant lesions, but also in the removal of many diminutive and small lesions leading to an increasing number of surveillance colonoscopies, known as the 'high-detection paradox'. More data on the cost-effectiveness of high-quality colonoscopy as a primary screening method and surveillance programs with intervals based on optimal risk stratification are eagerly awaited.

Colorectal Disorders in Acute Human Immunodeficiency Virus Infection: A Case Series

Background.  The gastrointestinal (GI) tract is important in the pathogenesis of human immunodeficiency virus (HIV) infection. We report a case series of lower GI endoscopic and histopathologic findings of HIV-infected individuals after presentation with acute infection. Methods.  We performed a retrospective case review of individuals infected with HIV who enrolled between August 2010 and April 2013 in a primary infection treatment trial. All participants started the trial during acute infection and underwent colonoscopy with biopsies at baseline and after the start of antiretroviral treatment. Results.  Twenty acutely infected individuals were included in the study (mean age, 33 years; range, 20-54 years). All participants were male who reported having receptive anal sex as an HIV risk factor. Nine individuals (45%) had at least 1 finding by colorectal pathology; 1 person had 2 diagnoses (diverticulosis and focal active proctitis). The histopathological findings revealed anal dysplasia in 3 cases: 2 had high-grade anal intraepithelial neoplasia (AIN) and 1 had low-grade AIN. Two persons had a colorectal polyp, 1 hyperplastic and 1 adenomatous. Three persons were diagnosed with diverticulosis, and 2 persons were diagnosed with proctitis, including 1 with focal active proctitis and 1 with cytomegalovirus proctitis. Conclusions.  To our knowledge, this is the first case series report of lower GI disorders in acute HIV-infected individuals. Although the causal relationship remains uncertain, we describe the endoscopic findings that were observed during acute HIV infection among men who have sex with men. Understanding the prevalence of these pathologies may likely shed light on how acute HIV infection damages the lower GI tract.

Colonoscopy detects significantly more flat adenomas than 3-tesla magnetic resonance colonography: a pilot trial

BACKGROUND AND STUDY AIMS

Colorectal cancer (CRC) is one of the most common cancers worldwide, and several efforts have been made to reduce its occurrence or severity. Although colonoscopy is considered the gold standard in CRC prevention, it has its disadvantages: missed lesions, bleeding, and perforation. Furthermore, a high number of patients undergo this procedure even though no polyps are detected. Therefore, an initial screening examination may be warranted. Our aim was to compare the adenoma detection rate of magnetic resonance colonography (MRC) with that of optical colonoscopy.

PATIENTS AND METHODS

A total of 25 patients with an intermediate risk for CRC (17 men, 8 women; mean age 57.6, standard deviation 11) underwent MRC with a 3.0-tesla magnet, followed by colonoscopy. The endoscopist was initially blinded to the results of MRC and unblinded immediately after examining the distal rectum. Following endoscopic excision, the size, anatomical localization, and appearance of all polyps were described according to the Paris classification.

RESULTS

A total of 93 lesions were detected during colonoscopy. These included a malignant infiltration of the transverse colon due to gastric cancer in 1 patient, 28 adenomas in 10 patients, 19 hyperplastic polyps in 9 patients, and 45 non-neoplastic lesions. In 5 patients, no lesion was detected. MRC detected significantly fewer lesions: 1 adenoma (P = 0.001) and 1 hyperplastic polyp (P = 0.004). The malignant infiltration was seen with both modalities. Of the 28 adenomas, 23 (82 %) were 5 mm or smaller; only 4 adenomas 10 mm or larger (14 %) were detected.

CONCLUSION

MRC does not detect adenomas sufficiently independently of the location of the lesion. Even advanced lesions were missed. Therefore, colonoscopy should still be considered the current gold standard, even for diagnostic purposes.

Vitamin D and Colorectal, Breast, and Prostate Cancers: A Review of the Epidemiological Evidence

Over the past two decades, the question of whether vitamin D has a role in cancer incidence, progression, and mortality has been studied in detail. Colorectal, breast, and prostate cancers have been a particular area of focus; together, these three malignancies account for approximately 35% of cancer cases and 20% of cancer deaths in the United States, and as such are a major public health concern. Herein, we review and synthesize the epidemiological research regarding vitamin D, as measured by the biomarker 25-hydroxycholecalciferol [25(OH)D], and the incidence, progression, and mortality of these cancers. Overall, the results of observational studies of the relationship between 25(OH)D and colorectal cancer have revealed a consistent inverse association for incidence and mortality; while for breast cancer, results have generally demonstrated a relationship between higher 25(OH)D and lower risk for progression and mortality. In contrast, randomized, double-blind clinical trials conducted to date have generally failed to support these findings. For prostate cancer, there is no convincing evidence of an association between 25(OH)D and incidence, and inconsistent data for progression and mortality, though results of one open label clinical trial suggest that supplementation with 4000 IU/d of vitamin D3 may inhibit progression of the disease. Nonetheless, until the results of additional ongoing randomized, double-blind clinical trials are reported, it will be difficult to ascertain if vitamin D itself is related to a reduction in risk for some cancer endpoints, or whether high concentrations of the vitamin D biomarker 25(OH)D may instead serve as a marker for an overall beneficial risk factor profile.

Chemoprevention trials of GI cancers in Asia

Cancers are among the leading causes of morbidity and mortality worldwide, with gastrointestinal (GI) luminal cancers accounting for a large proportion of cancer incidence. Chemoprevention of GI luminal cancers is important to reduce this cancer burden. Screening for and eradication of Helicobacter pylori (H. pylori) in areas with high gastric cancer incidence is a safe and effective strategy to decrease the incidence of gastric cancer. Eradication of H. pylori also seems to be effective in preventing metachronous cancer development after endoscopic resection of early gastric cancer. For the average risk individual, COX inhibitors may have a role in reducing the incidence of adenoma formation as well as colorectal cancer, bearing in mind its inherent risks. There is currently insufficient evidence to recommend a chemoprevention agent against esophageal and small intestine cancer.

[Role of Gastroenterologists in Management of Obesity]

Obesity is a serious disorder that increases morbidity and mortality. Primary intervention with life style modification and medication is not always effective for obese patients. Endoscopic management of obesity may be a less invasive, more cost-effective, and relatively safer option than bariatric surgery. Moreover, therapeutic endoscopy is considered to be the primary modality for managing complications that occur after bariatric surgery. In the near future, role of gastroenterologists will be more important in the management of obesity and its related problems.

Increased risk of colorectal polyps in patients with non-alcoholic fatty liver disease undergoing liver transplant evaluation

BACKGROUND

Screening colonoscopy is a standard part of the liver transplant (LT) evaluation process. We aimed to evaluate the yield of screening colonoscopy and determine whether non-alcoholic fatty liver disease (NAFLD) was associated with an increased risk of colorectal neoplasia.

METHODS

We retrospectively assessed all patients who completed LT evaluation at our center between 1/2008-12/2012. Patients <50 years old and those without records of screening colonoscopy, or with greater than average colon cancer risk were excluded.

RESULTS

A total of 1,102 patients were evaluated, 591 met inclusion criteria and were analyzed. The mean age was 60 years, 67% were male, 12% had NAFLD and 88% had other forms of chronic liver disease. Overall, 42% of patients had a polyp found on colonoscopy: 23% with adenomas, 14% with hyperplastic polyps and with 1% inflammatory polyps. In the final multivariable model controlling for age, NAFLD [odds ratio (OR) 2.41, P=0.001] and a history of significant alcohol use (OR 1.69, P=0.004) were predictive of finding a polyp on colonoscopy. In addition, NAFLD (OR 1.95, P=0.02), significant alcohol use (OR 1.70, P=0.01) and CTP class C (OR 0.57, P=0.02) were associated with adenoma, controlling for age.

CONCLUSIONS

Screening colonoscopy in patients awaiting LT yields a high rate of polyp (43%) and adenoma (22%) detection, perhaps preventing the accelerated progression to carcinoma that can occur in immunosuppressed post-LT patients. Patients with NAFLD may be at a ~2 fold higher risk of adenomas and should be carefully evaluated prior to LT.

Improved Detection of Microsatellite Instability in Early Colorectal Lesions

Microsatellite instability (MSI) occurs in over 90% of Lynch syndrome cancers and is considered a hallmark of the disease. MSI is an early event in colon tumor development, but screening polyps for MSI remains controversial because of reduced sensitivity compared to more advanced neoplasms. To increase sensitivity, we investigated the use of a novel type of marker consisting of long mononucleotide repeat (LMR) tracts. Adenomas from 160 patients, ranging in age from 29–55 years old, were screened for MSI using the new markers and compared with current marker panels and immunohistochemistry standards. Overall, 15 tumors were scored as MSI-High using the LMRs compared to 9 for the NCI panel and 8 for the MSI Analysis System (Promega). This difference represents at least a 1.7-fold increase in detection of MSI-High lesions over currently available markers. Moreover, the number of MSI-positive markers per sample and the size of allelic changes were significantly greater with the LMRs (p = 0.001), which increased confidence in MSI classification. The overall sensitivity and specificity of the LMR panel for detection of mismatch repair deficient lesions were 100% and 96%, respectively. In comparison, the sensitivity and specificity of the MSI Analysis System were 67% and 100%; and for the NCI panel, 75% and 97%. The difference in sensitivity between the LMR panel and the other panels was statistically significant (p<0.001). The increased sensitivity for detection of MSI-High phenotype in early colorectal lesions with the new LMR markers indicates that MSI screening for the early detection of Lynch syndrome might be feasible.

Characterizing Online Narratives About Colonoscopy Experiences: Comparing Colon Cancer "Screeners" Versus "Survivors"

Effective screening can reduce colorectal cancer mortality; however, screening uptake is suboptimal. Patients' stories about various health topics are widely available online and in behavioral interventions and are valued by patients. Although these narratives may be promising strategies for promoting cancer screening behavior, scant research has compared the influence of different role models. This study involving content analysis of online stories aimed to (a) describe the content of online experiential narratives about colonoscopy; (b) compare narratives from individuals who had a colonoscopy and either had colon cancer (survivors) or did not have colon cancer (screeners); and (c) generate hypotheses for future studies. The authors identified 90 narratives eligible for analysis from 15 websites. More stories were about White patients, men, and routine (vs. diagnostic) colonoscopy. A higher-than-expected number of narratives reported a family history of colorectal cancer or polyps (20%) and a colorectal cancer diagnosis (47%). Colorectal cancer survivor (vs. screener) stories were longer, mentioned symptoms and diagnostic reasons for getting a colonoscopy more often, and described the colonoscopy procedure or referred to it as easy or painless less often. Future studies should examine the effects of the role model's personal characteristics and the colonoscopy test result on reader's perceptions and intentions to have a colorectal cancer screening.

Multiple Gastrointestinal Polyps in Patients Treated with BRAF Inhibitors

PURPOSE

BRAF inhibitors (BRAFi) extend survival in BRAF-mutant melanoma but can promote the growth of Ras-mutant neoplasms. This study determined if gastrointestinal polyps found in BRAFi-treated patients harbored Ras mutations.

EXPERIMENTAL DESIGN

Colonic and gastric polyps were identified and resected from BRAFi-treated melanoma patients. Next-generation sequencing (NGS) was performed on polyps. The ability of BRAFi to promote polyp formation was functionally characterized in Apc Min(+/-) mice. MAPK and β-catenin pathway activity was assessed by immunohistochemistry in mouse and human polyps.

RESULTS

Fourteen patients treated with BRAFi underwent endoscopy to assess for polyps. Seven out of 7 patients >40 years of age and treated for >2 years were found to have colonic tubular adenomas with 4 out of the 7 patients having 5 or more polyps. One patient presented with bleeding from hyperplastic gastric polyps that recurred 6 months after BRAFi rechallenge. NGS performed on polyps found no mutations in MAPK pathway genes, but found APC mutations in all tubular adenomas. A significant increase in the number of polyps was observed in BRAFi-treated compared with control-treated Apc Min(+/-) mice (20.8 ± 9.2 vs 12.8 ± 0.1; P = 0.016). No polyps were observed in BRAFi-treated wild-type mice.

CONCLUSIONS

BRAFi may increase the risk of developing hyperplastic gastric polyps and colonic adenomatous polyps. Due to the risk of gastrointestinal bleeding and the possibility of malignant transformation, further studies are needed to determine whether or not endoscopic surveillance should be recommended for patients treated with BRAFi.

Long-term risk of colorectal cancer in individuals with serrated polyps

OBJECTIVE

Although serrated polyps may be precursors of colorectal cancer (CRC), prospective data on the long-term CRC risk in individuals with serrated polyps are lacking.

DESIGN

In a population-based randomised trial, 12,955 individuals aged 50-64 years were screened with flexible sigmoidoscopy, while 78 220 individuals comprised the control arm. We used Cox models to estimate HRs with 95% CIs for CRC among individuals with ≥1 large serrated polyp (≥10 mm in diameter), compared with individuals with adenomas at screening, and to population controls, and multivariate logistic regression to assess polyp risk factors for CRC.

RESULTS

A total of 103 individuals had large serrated polyps, of which 81 were included in the analyses. Non-advanced adenomas were found in 1488 individuals, advanced adenomas in 701. Median follow-up was 10.9 years. Compared with the control arm, the HR for CRC was 2.5 (95% CI 0.8 to 7.8) in individuals with large serrated polyps, 2.0 (95% CI 1.3 to 2.9) in individuals with advanced adenomas and 0.6 (95% CI 0.4 to 1.1) in individuals with non-advanced adenomas. A large serrated polyp was an independent risk factor for CRC, adjusted for histology, size and multiplicity of concomitant adenomas (OR 3.3; 95% CI 1.3 to 8.6). Twenty-three large serrated polyps found at screening were left in situ for a median of 11.0 years. None developed into a malignant tumour.

CONCLUSIONS

Individuals with large serrated polyps have an increased risk of CRC, comparable with individuals with advanced adenomas. However, this risk may not be related to malignant growth of the serrated polyp.

TRIAL REGISTRATION NUMBER

The Norwegian Colorectal Cancer Screening trial is registered at clinicaltrials.gov (NCT00119912).

The clinical epidemiology and malignancies associated with Streptococcus bovis biotypes in 506 cases of bloodstream infections

OBJECTIVES

To determine the incidence of Streptococcus bovis (Sb) biotypes causing bacteraemia and associated malignancies.

METHODS

This is a retrospective analysis of patients with Sb bacteraemia, pulled out from a prospective surveillance protocol of bacteraemia cases, in three areas of Spain (1990-2013): a cattle area (Lugo), a fishing area (Ferrol) and an urban area (Barcelona). Colonoscopy and Sb biotypes (Sb-I and Sb-II) were determined in most cases.

RESULTS

506 patients with Sb bacteraemia; mean age 68.1 (±14.1) years, and 66.2% were males. The cattle area, compared with the fishing and urban areas, had higher incidence of bacteraemia by SbI (40.29 vs 9.38 vs 6.15 cases/10(6) person-years, P < 0.001) and bacteraemia by Sb-II (29.07 vs 9.84 vs 13.37 cases/10(6) person-years, P < 0.001). The Sb-I cases (n = 224), compared with Sb-II cases (n = 270), had greater rates of endocarditis (77.6% vs 9.6%, P < 0.001) and colorectal neoplasm (CRN) (50.9% vs 16.6%, P < 0.001), and smaller rates of biliary tract infection (2.2% vs 29.6%, P < 0.001) and non-colorectal malignancy (8.9% vs 31.4%, P < 0.001).

CONCLUSION

There was a link between the cattle area and higher incidence of Sb bacteraemia. Sb-I differed from Sb-II cases in clinical findings and associated malignancies. Colonoscopy is mandatory in cases of endocarditis or bacteraemia caused by Sb-I.

Influence of perception of colorectal cancer risk and patient bowel preparation behaviors: a study in minority populations

BACKGROUND

Large disparities exist in the utilization rates of screening modalities for colorectal cancer (CRC) in different socioeconomic areas. In this study, we evaluated whether the quality of bowel preparation differed significantly among populations with a high risk of CRC compared with that among the general population after matching for potential confounding factors.

METHODS

Hispanic and African American patients who underwent routine screening or surveillance colonoscopies in an outpatient setting between 2003 and 2013 were included in this retrospective study. Patients who underwent colonoscopies for emergent indications and repeat routine screening colonoscopies because of prior history of inadequate bowel preparation were excluded from this study. The patients were divided into three groups: patients having an average risk of being diagnosed with CRC (group 1); patients having a high risk of being diagnosed with CRC because of a personal history of adenomatous polyps (group 2); and patients having a high risk of being diagnosed with CRC because of a family history of CRC in first-degree relatives (group 3). All the patients were given preprocedural counseling and written instructions for bowel preparation. Data on demographic information, method of bowel preparation, quality of bowel preparation, comorbidities, and prescription medications were collected.

RESULTS

In all, 834 patients had a "high-risk for CRC" surveillance colonoscopy in view of their personal history of adenomatous polyps and were included in group 2. In total, 250 patients had a "high-risk for CRC" screening colonoscopy in view of their family history of CRC in first-degree relatives and were included in group 3. Further, 1,000 patients were selected to serve as controls (after matching for age, sex and ethnicity) and were included in group 1. Bowel preparation was graded as good, fair, or poor by the endoscopist performing the study. We observed a significantly higher number of good bowel preparations in group 2 and group 3 (P=0.0001) when compared with group 1 (controls) after adjusting for comorbidities and usage of prescription medication that could potentially cause colonic dysmotility. These differences were significant in both Hispanic and African American patients.

CONCLUSION

Our study showed that perception of CRC risk significantly influenced the bowel preparation behaviors of patients belonging to minority populations, with a significantly greater number of patients with a high risk of CRC having adequate bowel preparations.

Risk factors for serrated polyps of the colorectum

Serrated pathway polyps are a relatively new area of interest in the field of colorectal cancer screening and prevention. Akin to conventional adenomas, some serrated polyps (SPs) have the potential to develop into malignant serrated neoplasms, yet little is known regarding risk factors for these lesions. Early epidemiological studies of hyperplastic polyps were performed without knowledge of the serrated pathway and likely included a mixture of SPs. More recently, studies have specifically evaluated premalignant SPs, such as the sessile serrated adenoma (SSA) or surrogates for these polyps such as large or proximally located SPs. SPs share some risk factors with conventional adenomas and have been associated with tobacco use, obesity, and age. Nonsteroidal anti-inflammatory drug (NSAID) use, fiber, folic acid, and calcium have been associated with reduced risk of SPs. Studies focused on SSAs specifically have reported associations with age, female sex, smoking, obesity, diabetes, and possibly diets high in fat, carbohydrates, and calories. Higher education has also been associated with risk of SSAs, while an inverse association between NSAID use and SSAs has been reported. Risk factors for traditional serrated adenomas are largely unknown. Studies are largely limited by varying inclusion criteria, as well as differences in pathological classification schemes. Further epidemiological studies of SPs are needed to aid in risk stratification and screening, and etiological research.

Adenoma detection rates in an opportunistic screening colonoscopy program in Iran, a country with rising colorectal cancer incidence

Background

Data on the quality of colonoscopies in populations with rising colorectal cancer (CRC) incidence is scarce. We aimed to calculate the adenoma detection rates (ADR), and assess the quality of colonoscopies in an opportunistic screening colonoscopy program in Iran.

Methods

All the colonoscopy and pathology reports of asymptomatic adults over age 50 who underwent screening colonoscopy between June 2007 and March 2013 were reviewed. The colonoscopy quality indicators including ADR were calculated, and patient factors associated with the adenoma detection were determined.

Results

A total of 713 asymptomatic adults aged 50 years and older who underwent their first-time screening colonoscopy were included in this study. ADR and advanced-ADR were 33.00% (95% CI: 29.52-36.54) and 13.18% (95% CI: 10.79-15.90), respectively. We observed a significantly higher rate of cecal intubation in patients with fair or better bowel preparation compared to those with poor prep, 90.00% vs. 70.45%, respectively (P < 0.001). Bowel preparation (adjusted OR: 2.49, 95% CI: 1.75-3.55), older age (≥60) (adjusted OR: 1.70, 95% CI: 1.22-2.36), and male gender (adjusted OR: 1.39, 95% CI: 1.01-1.92) were associated with the adenoma detection.

Conclusions

Our ADR in both genders meets and exceeds the recommended colonoscopy quality benchmarks. The polyp and adenoma detection rates in the current study are comparable to those reported from Western countries where the incidence of CRC is traditionally high. These data are in line with the epidemiologic transition of CRC in Iran.

Results of nurse navigator follow-up after positive colorectal cancer screening test: a randomized trial

BACKGROUND

Follow-up after a positive colorectal cancer screening test is necessary for screening to be effective. We hypothesized that nurse navigation would increase the completion of colonoscopy after a positive screening test.

METHODS

This study was conducted between 2008 and 2012 at 21 primary care medical centers in western Washington State. Participants in the Systems of Support to Increase Colorectal Cancer Screening study who had a positive fecal occult blood test (FOBT) or flexible sigmoidoscopy needing follow-up were randomized to usual care (UC) or a nurse navigator (navigation). UC included an electronic health record-based positive FOBT registry and physician reminder system. Navigation included UC plus care coordination and patient self-management support from a registered nurse who tracked and assisted patients until they completed or refused colonoscopy. The primary outcome was completion of colonoscopy within 6 months. After 6 months, both groups received navigation.

RESULTS

We randomized 147 participants with a positive FOBT or sigmoidoscopy. Completion of colonoscopy was higher in the intervention group at 6 months, but differences were not statistically significant (91.0% in navigation group vs 80.8% in UC group; adjusted difference, 10.1%; P = .10). Reasons for no or late colonoscopies included refusal, failure to schedule or missed appointments, concerns about risks or costs, and competing health concerns.

CONCLUSIONS

Navigation did not lead to a statistically significant incremental benefit at 6 months.

IMPACT

Follow-up rates after a positive colorectal cancer (CRC) screening test are high in a health care system where UC included a registry and physician reminders. Because of high follow-up rates in a health care system where UC included a registry and physician reminders, and small sample size, we cannot rule out incremental benefits of nurse navigation.

Assessing bowel preparation quality using the mean number of adenomas per colonoscopy

INTRODUCTION

The quality of the bowel preparation directly influences colonoscopy effectiveness. Quality indicators are widely employed to monitor operator performance and to gauge colonoscopy effectiveness. Some have suggested that the enumeration of the mean number of adenomas per colonoscopy (MNA) may be a more useful measure of bowel preparation quality, but evidence of the utility of this metric is limited. The relationship between bowel preparation quality and MNA was assessed.

METHODS

Records of adult patients, aged 50-74 years, who had undergone a screening colonoscopy in a 6 month period at a hospital-based endoscopy suite in New York City were examined. Excluded were those who were symptomatic or having a colonoscopy for surveillance. Patient and procedural characteristics and clinical findings were abstracted from the endoscopy database. Bowel preparation quality was recorded as excellent, good, fair and poor. Histology and size of polyps removed were gathered from pathology reports. MNA was calculated and incident rate ratios assessing the relationship between bowel preparation quality, MNA, and covariates was calculated using Poisson regression.

RESULTS

A total of 2422 colonoscopies were identified; 815 (33.6%) were screening colonoscopies among average risk individuals, 50-74 years; 203 (24.9%) had ≥1 adenomas; and 666 (81.7%) had excellent/good preparation quality. Overall MNA was 0.34 [standard deviation (SD) 0.68] and MNA was greater among those >60 years [incident rate ratio (IRR) 1.89, 95% confidence interval (CI) 1.48-2.42), males (IRR 1.60, 95%CI 1.26-2.04) and those with good bowel preparation (IRR 2.54, 95%CI 1.04-6.16). Among those with ≥1 adenomas, MNA was 1.48 (SD 1.05) for excellent and 1.00 (SD 0.00) for poor quality preparation (p = 0.55).

CONCLUSIONS

We found that MNA is sensitive to changes in bowel preparation with higher MNA among those with good bowel preparation compared with those with poor preparation. Our evidence suggests MNA was particularly sensitive when restricted to only those in whom adenomas were seen.

Molecular markers of carcinogenesis for risk stratification of individuals with colorectal polyps: a case-control study

Risk stratification using number, size, and histology of colorectal adenomas is currently suboptimal for identifying patients at increased risk for future colorectal cancer. We hypothesized that molecular markers of carcinogenesis in adenomas, measured via immunohistochemistry, may help identify high-risk patients. To test this hypothesis, we conducted a retrospective, 1:1 matched case-control study (n = 216; 46% female) in which cases were patients with colorectal cancer and synchronous adenoma and controls were patients with adenoma but no colorectal cancer at baseline or within 5 years of follow-up. In phase I of analyses, we compared expression of molecular markers of carcinogenesis in case and control adenomas, blind to case status. In phase II of analyses, patients were randomly divided into independent training and validation groups to develop a model for predicting case status. We found that seven markers [p53, p21, Cox-2, β-catenin (BCAT), DNA-dependent protein kinase (DNApkcs), survivin, and O6-methylguanine-DNA methyltransferase (MGMT)] were significantly associated with case status on unadjusted analyses, as well as analyses adjusted for age and advanced adenoma status (P < 0.01 for at least one marker component). When applied to the validation set, a predictive model using these seven markers showed substantial accuracy for identifying cases [area under the receiver operation characteristic curve (AUC), 0.83; 95% confidence interval (CI), 0.74-0.92]. A parsimonious model using three markers performed similarly to the seven-marker model (AUC, 0.84). In summary, we found that molecular markers of carcinogenesis distinguished adenomas from patients with and without colorectal cancer. Furthermore, we speculate that prospective studies using molecular markers to identify individuals with polyps at risk for future neoplasia are warranted.

Low rate of large polyps (>9 mm) within 10 years after an adequate baseline colonoscopy with no polyps

BACKGROUND & AIMS

Guidelines recommend a 10-year interval between screening colonoscopies with negative results for average-risk individuals. However, many patients are examined at shorter intervals. We investigated outcomes of individuals with no polyps who had repeat colonoscopy in <10 years.

METHODS

Data were collected using the National Endoscopic Database, from 69 gastroenterology centers, on 264,184 asymptomatic subjects who underwent screening colonoscopies from 2000 through 2006, were found to have no polyps, and received another colonoscopy examination within <10 years.

RESULTS

No polyps were found in 147,375 patients during a baseline colonoscopy; 17,525 patients (11.9%) had a follow-up colonoscopy within <10 years, including 1806 (10.3%) who received the follow-up colonoscopy within <1 year. The most common reason for repeating the examination within 1 year was that the first was compromised by inadequate bowel preparation or incomplete examination. Of these patients, 6.5% (95% confidence interval: 5.3-7.6) had large polyp(s) >9 mm-a proportion similar to the prevalence in the average-risk screening population. Reasons that examinations were repeated within 1-5 years included average-risk screening (15.7%), family history of colon polyps or cancer (30.1%), bleeding (31.2%), gastrointestinal symptoms (11.8%), or a positive result from a fecal blood test (5.5%). If the baseline examination was adequate, the incidence of large polyps within 1-5 years after baseline colonoscopy was 3.1% (95% confidence interval: 2.7-3.5) and within years 5-10 years was 3.7% (95% confidence interval: 3.3-4.1).

CONCLUSIONS

Repeat colonoscopies within 10 years are of little benefit to patients who had adequate examinations and were found to have no polyps. Repeat colonoscopies are beneficial to patients when the baseline examination was compromised.

Race, ethnicity, and sex affect risk for polyps >9 mm in average-risk individuals

BACKGROUND & AIMS

Colorectal cancer risk differs based on patient demographics. We aimed to measure the prevalence of significant colorectal polyps in average-risk individuals and to determine differences based on age, sex, race, or ethnicity.

METHODS

In a prospective study, colonoscopy data were collected, using an endoscopic report generator, from 327,785 average-risk adults who underwent colorectal cancer screening at 84 gastrointestinal practice sites from 2000 to 2011. Demographic characteristics included age, sex, race, and ethnicity. The primary outcome was the presence of suspected malignancy or large polyp(s) >9 mm. The benchmark risk for age to initiate screening was based on white men, 50-54 years old.

RESULTS

Risk of large polyps and tumors increased progressively in men and women with age. Women had lower risks than men in every age group, regardless of race. Blacks had higher risk than whites from ages 50 through 65 years and Hispanics had lower risk than whites from ages 50 through 80 years. The prevalence of large polyps was 6.2% in white men 50-54 years old. The risk was similar among the groups of white women 65-69 years old, black women 55-59 years old, black men 50-54 years old, Hispanic women 70-74 years old, and Hispanic men 55-59 years old. The risk of proximal large polyps increased with age, female sex, and black race.

CONCLUSIONS

There are differences in the prevalence and location of large polyps and tumors in average-risk individuals based on age, sex, race, and ethnicity. These findings could be used to select ages at which specific groups should begin colorectal cancer screening.

Participation and detection rates by age and sex for colonoscopy versus fecal immunochemical testing in colorectal cancer screening

PURPOSE

To compare two strategies for colorectal cancer screening: one-time colonoscopy versus fecal immunochemical testing (FIT) (and colonoscopy for positive) every 2 years, in order to determine which strategy provides the highest participation and detection rates in groups of sex and age.

METHODS

This analysis was performed with data from the first screening round within the COLONPREV study, a population-based, multicenter, nationwide trial carried out in Spain. Several logistic regression models were applied to identify the influence of the screening test on participation rates and detection of proximal and distal neoplasms, as well to identify the influence of age and sex: women aged 50-59 years, women aged 60-69 years, men aged 50-59 years, and men aged 60-69 years.

RESULTS

Participation was higher in women than in men, especially among women aged 50-59 years (25.91 % for colonoscopy and 35.81 % for FIT). Crossover from colonoscopy to FIT was higher among women than men, especially among those aged 60-69 years (30.37 %). In general, detection of any neoplasm and advanced adenoma was higher with colonoscopy than with FIT, but no significant differences were found between the two strategies for colorectal cancer detection. Detection of advanced adenoma in both arms was lower in women [specifically in women aged 50-59 years (OR 0.31; 95 % CI 0.25-0.38) than in men aged 60-69 years]. Women aged 50-59 years in the colonoscopy arm had a higher probability of detection of advanced adenoma (OR 4.49; 95 % CI 3.18-6.35), as well as of detection of neoplasms in proximal and distal locations (proximal OR 19.34; 95 % CI 12.07-31.00; distal OR 11.04; 95 % CI 8.13-15.01) than women of the same age in the FIT arm. These differences were also observed in the remaining groups but to a lesser extent.

CONCLUSION

Women were more likely to participate in a FIT-based strategy, especially those aged 50-59 years. The likelihood of detection of any neoplasm was higher in the colonoscopy arm for all the population groups studied, especially in women aged 50-59 years. Distinct population groups should be informed of the benefits of each screening strategy so that they may take informed decisions.

Variation in the association between colorectal cancer susceptibility loci and colorectal polyps by polyp type

We conducted a case-control study of the association between subsets of colorectal polyps, including adenomas and serrated polyps, and single-nucleotide polymorphisms (SNPs) related to colorectal cancer through prior genome-wide association studies (GWAS). Participants were enrollees in the Group Health Cooperative (Seattle, Washington) aged 24-79 years who received a colonoscopy from 1998 to 2007, donated a buccal or blood sample, and completed a structured questionnaire. We performed genotyping of 13 colorectal cancer susceptibility SNPs. Polytomous logistic regression models were used to estimate odds ratios and 95% confidence intervals for associations between polyps and the colorectal cancer risk allele for each SNP under a log-additive model. Analyses included 781 controls, 489 cases with adenoma, 401 cases with serrated polyps, and 188 cases with both polyp types. The following SNPs were associated with advanced adenomas: rs10936599, rs10795668, rs16892766, and rs9929218 (P < 0.05). For nonadvanced adenomas and for serrated polyps overall, only rs961253 was statistically significant (P < 0.05). These associations were in the same directions as those in prior colorectal cancer GWAS. No SNP was significantly associated with hyperplastic polyps, and only rs6983267 was significantly associated with sessile serrated polyps, but this association was opposite of that found in colorectal cancer GWAS. Our results suggest that the association between colorectal cancer susceptibility SNPs and colorectal polyps varies by polyp type.

Endoscopic mucosal resection and endoscopic submucosal dissection of epithelial neoplasia of the colon

Endoscopic mucosal resection (EMR) with curative intent has evolved into a safe and effective technique and is currently the gold standard for management of large colonic epithelial neoplasms. Piecemeal EMR is associated with a high risk of local recurrence requiring vigilant surveillance and repeat interventions. Endoscopic submucosal dissection (ESD) was introduced in Japan for the management of early gastric cancer, and has recently been described for en bloc resection of colonic lesions greater than 20 mm. En bloc resection allows accurate histological assessment of the depth of invasion, minimizes the risk of local recurrence and helps determine additional therapy. Morphologic classification of lesions prior to resection allows prediction of depth of invasion and risk of nodal metastasis, allowing selection of the appropriate intervention. This review provides an overview of the assessment of epithelial neoplasms of the colon and the application of EMR and ESD techniques in their management.

Colonoscopy utilization and outcomes 2000 to 2011

BACKGROUND

Understanding colonoscopy utilization and outcomes can help determine when the procedure is most effective.

OBJECTIVE

To study trends in utilization and outcomes of colonoscopy in the United States from 2000 to 2011.

DESIGN

Prospective collection of colonoscopy data.

SETTING

A total of 84 adult diverse GI practices.

PATIENTS

All adult patients receiving colonoscopy for any reason.

INTERVENTION

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

Polyps >9 mm or suspected malignant tumor.

RESULTS

We analyzed 1,372,838 reports. The most common reason for colonoscopy in patients aged <50 years is evaluation of symptoms such as irritable bowel syndrome (IBS) (28.7%) and bleeding or anemia (35.3%). In patients aged 50 to 74 years, colorectal cancer screening accounts for 42.9% of examinations. In patients aged >74 years, surveillance for cancer or polyps is the most common indication. The use of colonoscopy for average-risk screening increased nearly 3-fold during the study period. The prevalence of large polyps increases with age and is higher in men for every procedure indication. The prevalence of large polyps in patients with symptoms of IBS was lower than in those undergoing average-risk screening (odds ratio [OR] 0.85; 95% confidence interval [CI], 0.83-0.87). With increasing age, there was a shift from distal to proximal large polyps. The rate of proximal large polyps is higher in the black population compared with the white population (OR 1.19; 95% CI, 1.13-1.25).

LIMITATIONS

In the absence of pathology data, use of surrogate as the main outcome.

CONCLUSION

Colonoscopy utilization changed from 2000 to 2011, with an increase in primary screening. The proximal location of large polyps in the black population and with advancing age has implications for screening and surveillance.

Developing screening services for colorectal cancer on Android smartphones

INTRODUCTION

Colorectal cancer (CRC) is an important health problem in Western countries and also in Asia. It is the third leading cause of cancer deaths in both men and women in Taiwan. According to the well-known adenoma-to-carcinoma sequence, the majority of CRC develops from colorectal adenomatous polyps. This concept provides the rationale for screening and prevention of CRC. Removal of colorectal adenoma could reduce the mortality and incidence of CRC. Mobile phones are now playing an ever more crucial role in people's daily lives. The latest generation of smartphones is increasingly viewed as hand-held computers rather than as phones, because of their powerful on-board computing capability, capacious memories, large screens, and open operating systems that encourage development of applications (apps).

SUBJECTS AND METHODS

If we can detect the potential CRC patients early and offer them appropriate treatments and services, this would not only promote the quality of life, but also reduce the possible serious complications and medical costs. In this study, an intelligent CRC screening app on Android™ (Google™, Mountain View, CA) smartphones has been developed based on a data mining approach using decision tree algorithms. For comparison, the stepwise backward multivariate logistic regression model and the fecal occult blood test were also used.

RESULTS

Compared with the stepwise backward multivariate logistic regression model and the fecal occult blood test, the proposed app system not only provides an easy and efficient way to quickly detect high-risk groups of potential CRC patients, but also brings more information about CRC to customer-oriented services.

CONCLUSIONS

We developed and implemented an app system on Android platforms for ubiquitous healthcare services for CRC screening. It can assist people in achieving early screening, diagnosis, and treatment purposes, prevent the occurrence of complications, and thus reach the goal of preventive medicine.

Vegetarianism as a protective factor for colorectal adenoma and advanced adenoma in Asians

BACKGROUND

Although epidemiologic and animal studies suggest a vegetarian diet protects against the development of colorectal cancer, the relationship between vegetarian diet and incidence of colorectal adenoma is not yet conclusive, especially for Asians.

AIM

The purpose of this study was to examine the protective effect of a vegetarian diet against colorectal adenoma and advanced adenoma.

METHODS

This cross-sectional study compared the prevalence of colorectal adenoma among Buddhist priests, who are obligatory vegetarians, with that among age and sex-matched controls. All the subjects underwent health checkups in a health-promotion center in Korea.

RESULT

Colorectal adenoma and advanced adenoma were both more prevalent in the general population group than in the Buddhist priest group (25.2 vs. 17.9 %, 6.7 vs. 2.0 %). However, the prevalence of metabolic syndrome, high body mass index, and waist circumference were higher in the Buddhist priest group. According to univariate analysis, non-vegetarian diet (general population) significantly increased the prevalence of colorectal adenoma and advanced adenoma compared with a vegetarian diet (Buddhist priests) (OR 1.54, 95 % CI 1.08-2.21, P = 0.018; OR 3.60, 95 % CI 1.53-8.48, P = 0.003). In a conditional regression analysis model, non-vegetarian diet was also a significant risk factor for colorectal adenoma and advanced adenoma (OR 1.52, 95 % CI 0.75-2.07, P = 0.043; OR 2.94, CI 0.97-7.18, P = 0.036).

CONCLUSIONS

Vegetarianism may be effective in preventing both colorectal adenoma and advanced adenoma in Asians.

Profile of colorectal polyps: a retrospective study from King Fahad Hospital, Madinah, Saudi Arabia

AIM

To evaluate the predominant colorectal polyps in the Almadinah region of Saudi Arabia.

MATERIALS AND METHODS

In this iretrospective study, we analyzed pathology reports of colonoscopies performed in King Fahad Hospital, Madinah, Saudi Arabia during the period 2006 to 2013. Data based on patient age, gender, size, site and type of polyps and the degree of dysplasia were analyzed by software SPSS 17 and compared with other published studies from different geographic regions of the world.

RESULTS

During these years, 224 patients had colonic polyps, of whom 149 (66.5%) were men and 75 (33.5%) were women. The most common types of polyps were adenomatous (166), followed by hyperplastic polyps (24), juvenile (18), inflammatory (13), lipomatous (2) and one patient with Peutz-Jegher polyps. Tubulovillous adenoma was the commonest adenomatous polyp (102), followed by tubular (41) and villous (23) types. The sigmoid colon was the most commonly involved region (36.6%). Dysplasia was significantly associated with female patients who had large size tubulovillous polyps located in the left colon.

CONCLUSIONS

The type and distribution of colorectal polyps in Saudi Arabia is very similar to Western countries. Patient gender, and size, histological type and location of polyps are closely related to dysplastic change in colonic polyps.

Navigating the murky waters of colorectal cancer screening and health reform

The Affordable Care Act (ACA) mandates that both Medicaid and insurance plans cover life-saving preventive services recommended by the US Preventive Services Task Force, including colorectal cancer (CRC) screening and choice between colonoscopy, flexible sigmoidoscopy, and fecal occult blood testing (FOBT). People who choose FOBT or sigmoidoscopy as their initial test could face high, unexpected, out-of-pocket costs because the mandate does not cover needed follow-up colonoscopies after positive tests. Some people will have no coverage for any CRC screening because of lack of state participation in the ACA or because they do not qualify (e.g., immigrant workers). Existing disparities in CRC screening and mortality will worsen if policies are not corrected to fully cover both initial and follow-up testing.

Rural-urban differences in the long-term risk of colorectal cancer after adenoma removal: a population-based study

BACKGROUND

We investigated the impact of municipality of residence on colonoscopic surveillance and colorectal cancer risk after adenoma resection in a French well-defined administrative area.

METHODS

This registry-based study included all patients residing in Côte d'Or (n=5769) first diagnosed with colorectal adenomas between January 1, 1990, and December 31, 1999. Information about colonoscopic surveillance and colorectal cancer incidence was collected until December 31, 2003.

RESULTS

A rural place of residence reduced the probability of colonoscopic surveillance in men [HR=0.89 (95%CI: 0.79-0.99), p=0.041] and in patients without family history of colorectal cancer [HR=0.91(0.82-0.99), p=0.044]. After a median follow-up of 7.7 years, 87 patients developed invasive colorectal cancer. After advanced adenoma removal, the standardized incidence ratio for colorectal cancer was 3.03 (95%CI: 1.92-4.54) for rural patients and 1.87 (95%CI: 1.26-2.66) for urban patients compared with the general population. The risk of colorectal cancer was higher in rural patients than in urban ones only after removal of the initial advanced adenoma [HR=1.73 (95%CI: 1.01-3.00, p=0.048)]. Further adjustment for surveillance colonoscopy, physician location, and other confounders had little impact on these results.

CONCLUSION

The increased risk of subsequent colorectal cancer after advanced adenoma removal in French rural patients was not explained by a lower rate of colonoscopic surveillance. The role of socio-economic and environmental factors requires further exploration.

Prevalence of colorectal polyps in a group of subjects at average-risk of colorectal cancer undergoing colonoscopic screening in Tehran, Iran between 2008 and 2013

BACKGROUND

Colorectal cancer (CRC) is one of the prime causes of mortality around the globe, with a significantly rising incidence in the Middle East region in recent decades. Since detection of CRC in the early stages is an important issue, and also since to date there are no comprehensive epidemiologic studies depicting the Middle East region with special attention to the average risk group, further investigation is of significant necessity in this regard.

AIM

Our aim was to investigate the prevalence of preneoplastic and neoplastic lesions of the colon in an average risk population.

MATERIALS AND METHODS

A total of 1,208 eligible asymptomatic, average- risk adults older than 40 years of age, referred to Firuzgar Hospotal in the years 2008-2012, were enrolled. They underwent colonoscopy screening and all polypoid lesions were removed and examined by an expert gastrointestinal pathologist. The lesions were classified by size, location, numbers and pathologic findings. Size of lesions was measured objectively by endoscopists.

RESULTS

The mean age of participants was 56.5±9.59 and 51.6% were male. The overall polyp detection rate was 199/1208 (16.5 %), 26 subjects having non-neoplastic polyps, including hyperplastic lesions, and 173/1208 (14.3%) having neoplastic polyps, of which 26 (2.15%) were advanced neoplasms .The prevalence of colorectal neoplasia was more common among the 50-59 age group. Advanced adenoma was more frequent among the 60-69 age group. The majority of adenomas were detected in the distal colon, but a quarter of advanced adenomas were found in the proximal colon; advance age and male gender was associated with the presence of adenoma.

CONCLUSIONS

It seems that CRC screening among average-risk population might be recommended in countries such as Iran. However, sigmioidoscopy alone would miss many colorectal adenomas. Furthermore, the 50-59 age group could be considered as an appropriate target population for this purpose in Iran.

Noncathartic CT colonography to screen for colorectal neoplasia in subjects with a family history of colorectal cancer

PURPOSE

To prospectively assess the diagnostic performance of noncathartic computed tomographic (CT) colonography in the detection of clinically relevant colorectal lesions (≥6 mm polyps or masses) in a well-defined cohort of first-degree relatives of patients with colorectal cancer (CRC), using colonoscopy and histologic review as the standard of reference.

MATERIALS AND METHODS

Institutional review board approval was obtained, and all subjects provided written informed consent. Consecutive patients admitted with CRC (index cases) were prospectively evaluated, and those who agreed to contact their first-degree relatives who were at least 40 years old were included. Available first-degree relatives were invited to undergo noncathartic CT colonography (200 mL of diatrizoate meglumine and diatrizoate sodium). Colonoscopy was performed the following day, and findings from CT colonography were disclosed for each segment. Sensitivity, specificity, and positive and negative predictive values of CT colonography were assessed for detecting subjects with any lesion at least 6 mm, any lesion at least 10 mm, and advanced neoplasia at least 6 mm. Colonoscopy with segmental unblinding and histologic diagnosis were used as the standard of reference. Matching between findings from CT colonography and colonoscopy was allowed when lesions were located in the same or adjacent colon segments and when the size difference was 50% or less.

RESULTS

Three hundred four first-degree relatives (median age, 47 years; age range, 40-79 years; 46.7% women) identified from 221 index cases were included. Overall, CT colonography helped identify 17 of 22 subjects with polyps measuring at least 6 mm (sensitivity, 0.77; 95% confidence interval [CI]: 0.59, 0.95) and helped correctly classify as negative 278 of 282 subjects without lesions measuring at least 6 mm (specificity, 0.99; 95% CI: 0.97, 1.00). CT colonography helped detect eight of nine subjects with polyps measuring at least 10 mm as well as eight of nine subjects with advanced neoplasia measuring at least 6 mm (sensitivity, 0.89 for both). Per-subject positive and negative predictive values for lesions measuring at least 6 mm were 0.81 (17 of 21 subjects; 95% CI: 0.65, 0.97) and 0.98 (282 of 287 subjects; 95% CI: 0.96, 0.99), respectively.

CONCLUSION

Noncathartic CT colonography is an effective screening method in first-degree relatives of patients with CRC.

Immunochemical fecal occult blood test for detection of advanced colonic adenomas and colorectal cancer: comparison with colonoscopy results

Background. Fecal immunochemical tests (FITs) have been used for colorectal cancer (CRC) screening in several countries. There is lack of information concerning diagnostic performances of this method in Brazil. Methods. Patients scheduled for elective colonoscopy provided one stool sample one week before colonoscopy. The accuracy of a qualitative FIT for detection of CRC and advanced adenomas was determined. Results. Overall 302 patients completed the study. Among them, 53.5% were high risk patients referred for screening or surveillance. Nine (3%) CRCs and 11 (3.6%) advanced adenomas were detected by colonoscopy. Sensitivity and specificity for CRC were, respectively, 88.9% and 87.6%. For advanced adenomas, sensitivity was 63.6% and specificity 87.6%. Conclusion. Our results showed good sensitivity and specificity of the FIT for detecting advanced neoplasias. This method may be a valuable tool for future screening programs in Brazil.

Colonoscopy following nonoperative management of uncomplicated diverticulitis may not be warranted

BACKGROUND

Following the nonoperative management of acute diverticulitis, guidelines recommend routine follow-up colonoscopy; however, evidence to support this recommendation are lacking.

OBJECTIVE

This study aims to determine the diagnostic yield of endoscopy for clinically significant neoplasia following the successful nonoperative management of acute diverticulitis.

DESIGN

This study is a retrospective review.

SETTING

This study was conducted in a large urban health region.

PATIENTS

Adult patients who were admitted with a diagnosis of acute diverticulitis confirmed by CT and who were successfully managed nonoperatively to hospital discharge were included. Patients who underwent colonoscopy within 2 years of presentation were excluded.

MAIN OUTCOME MEASURE

The primary outcome measured was the incidence of clinically significant neoplasia (invasive malignancy or advanced adenoma) on follow-up endoscopy within 1 year of admission.

RESULTS

Four hundred fifty-eight patients were selected for analysis, of which 249 patients (54%) underwent endoscopy within 1 year of admission. Seventy-seven (30.9%) patients were found to have polyps, 19 (7.6%) patients had advanced adenomas, and 4 (1.6%) patients had an invasive malignancy; 23 patients (9.2%) were found to have clinically significant neoplasia. On subgroup analysis, patients presenting with complicated diverticulitis (n = 74) had a significantly higher incidence of advanced adenoma (18.9% vs 5%, p = 0.001) and invasive malignancy (5.4% vs 0%, p = 0.007) in comparison with patients who presented with uncomplicated diverticulitis (n = 175). On multivariate analysis, patient age (OR 1.04 (1.01-1.08), p = 0.02) and the presence of abscess (OR 4.15 (1.68-10.3), p = 0.002) were identified as significant risk factors for clinically significant neoplasia.

LIMITATIONS

The use of retrospective data was a limitation of this study; 54% of selected patients underwent endoscopic follow-up.

CONCLUSIONS

The incidence of clinically significant neoplasia on endoscopic follow-up after the nonoperative management of acute diverticulitis is 9.2%. Those with complicated diverticulitis are at higher risk, whereas the incidence of clinically significant neoplasia in those with uncomplicated diverticulitis is equal to the incidence in average-risk individuals. Routine diagnostic colonoscopy following the nonoperative management of acute uncomplicated diverticulitis may not be warranted.

Prevalence and lifetime risk of endoscopy-related complications among patients with inflammatory bowel disease

BACKGROUND & AIMS

Few studies have analyzed the safety of endoscopy in patients with inflammatory bowel disease (IBD). We aimed to determine the prevalence of procedure-related complications among these patients, compared with the general population, and estimate the lifetime risk of colonoscopy-related complications.

METHODS

We collected data on complications in 685 patients with IBD and 17,000 patients without IBD (controls) using an automated system to track all emergency department visits to the Beth Israel Deaconess Medical Center within 14 days of an endoscopic procedure, from March 1, 2007, to November 30, 2007. We reviewed charts of all IBD patients to determine health care use (telephone calls or visits to a gastroenterologist or primary care physician and visits to other emergency departments or hospitals) after endoscopy. The lifetime risk of procedure-related complications was estimated using a Markov Monte Carlo model.

RESULTS

Rates of complications were 1.17% among patients with IBD and 0.96% among controls (P = .55). The chart review showed that 3.8% of the IBD cohort received medical care within 14 days of the endoscopic procedure. Based on a Markov Monte Carlo simulation model, the lifetime risk of complications after a surveillance colonoscopy protocol was 12.7% among patients with IBD and 2.0% in the general population undergoing screening colonoscopy (P < .001).

CONCLUSIONS

Although the risk of adverse events after each endoscopic procedure was similar for patients with IBD and the general population, IBD patients have an increased lifetime risk of complications after colonoscopies. A higher percentage of patients with IBD also seek medical care after endoscopic procedures than controls.

Classification criteria for advanced adenomas of the colon by using probe-based confocal laser endomicroscopy: a preliminary study

BACKGROUND

Probe-based confocal laser endomicroscopy may allow a strategy of "diagnose, resect, and discard" for small nonadvanced adenomas, but there are concerns about discarding polyps with advanced histology.

OBJECTIVE

The aim of this study was to evaluate the potential use of probe-based confocal laser endomicroscopy to aid in distinguishing low-grade from advanced colon adenomas.

DESIGN

Six observers, blinded to histopathology, scored 5 adenoma features and an overall diagnosis and confidence level for the diagnosis.

SETTING

This study was conducted at single, tertiary care referral center.

PATIENTS

Patients undergoing screening and surveillance colonoscopies and for whom an adenomatous polyp was removed were included.

INTERVENTIONS

A sample of 27 advanced adenomas and 120 nonadvanced adenomas were used in the study. An initial classification system was created with 10 advanced and 10 nonadvanced adenomas. The remaining 127 adenomas were scored by each observer in the validation portion of the study.

MAIN OUTCOME MEASURES

The primary outcome measured was the accurate classification of advanced and nonadvanced adenomas.

RESULTS

Overall, across all 6 observers, the sensitivity in correctly classifying advanced adenomas was 43%, the negative predictive value was 89%, the specificity was 71%, and the positive predictive value was 19%. No single feature or combination of features as seen with probe-based confocal laser endomicroscopy consistently identified advanced adenomas.

LIMITATIONS

Classification criteria were developed subjectively, and there was limited observer experience with probe-based confocal laser endomicroscopy use.

CONCLUSIONS

Our initial attempt at creating classification criteria for probe-based confocal laser endomicroscopy did not consistently distinguish advanced from nonadvanced adenomas and, therefore, is not useful in applying a "diagnose, resect, and discard" strategy. However, further refinement of our probe-based confocal laser endomicroscopy classification scheme in future studies has potential to accurately detect advanced histology in colorectal polyps.

Relationship of colonoscopy-detected serrated polyps with synchronous advanced neoplasia in average-risk individuals

BACKGROUND

Serrated cancers account for 10% to 20% of all colorectal cancers (CRC) and more than 30% of interval cancers. The presence of proximal serrated polyps and large (≥10 mm) serrated polyps (LSP) has been correlated with colorectal neoplasia.

OBJECTIVE

To evaluate the prevalence of serrated polyps and their association with synchronous advanced neoplasia in a cohort of average-risk population and to assess the efficacy of one-time colonoscopy and a biennial fecal immunochemical test for reducing CRC-related mortality. This study focused on the sample of 5059 individuals belonging to the colonoscopy arm.

DESIGN

Multicenter, randomized, controlled trial.

SETTING

The ColonPrev study, a population-based, multicenter, nationwide, randomized, controlled trial.

PATIENTS

A total of 5059 asymptomatic men and women aged 50 to 69 years.

INTERVENTION

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

Prevalence of serrated polyps and their association with synchronous advanced neoplasia.

RESULTS

Advanced neoplasia was detected in 520 individuals (10.3%) (CRC was detected in 27 [0.5%] and advanced adenomas in 493 [9.7%]). Serrated polyps were found in 1054 individuals (20.8%). A total of 329 individuals (6.5%) had proximal serrated polyps, and 90 (1.8%) had LSPs. Proximal serrated polyps or LSPs were associated with male sex (odds ratio [OR] 2.08, 95% confidence interval [CI], 1.76-4.45 and OR 1.65, 95% CI, 1.31-2.07, respectively). Also, LSPs were associated with advanced neoplasia (OR 2.49, 95% CI, 1.47-4.198), regardless of their proximal (OR 4.15, 95% CI, 1.69-10.15) or distal (OR 2.61, 95% CI, 1.48-4.58) locations. When we analyzed subtypes of serrated polyps, proximal hyperplasic polyps were related to advanced neoplasia (OR 1.61, 95% CI, 1.13-2.28), although no correlation with the location of the advanced neoplasia was observed.

LIMITATIONS

Pathology criteria for the diagnosis of serrated polyps were not centrally reviewed. The morphology of the hyperplasic polyps (protruded or flat) was not recorded. Finally, because of the characteristics of a population-based study carried out in average-risk patients, the proportion of patients with CRC was relatively small.

CONCLUSION

LSPs, but not proximal serrated polyps, are associated with the presence of synchronous advanced neoplasia. Further studies are needed to determine the risk of proximal hyperplastic polyps.

A comparison of positron emission tomography and colonoscopy for the detection of advanced colorectal neoplasms in subjects undergoing a health check-up

Background & Aims

There is no agreement as to whether F-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT) screening for advanced colorectal neoplasms is meaningful. This retrospective study was undertaken to determine whether FDG PET/CT may be a valuable screening tool for the detection of advanced colorectal neoplasms.

Methods

A retrospective review of the records of 1,109 FDG PET/CT scans acquired from January 2007 to December 2011 was performed. Colonoscopy and FDG PET/CT imaging were performed within two days of each other. The results of colonoscopy were taken as the gold standard, either with or without the results of the histopathological examination. An advanced neoplasm was defined as the presence of a malignant tumor, an adenoma ≥1 cm, or histological evidence of high-grade dysplasia or significant villous components.

Results

A total of 36 subjects had advanced colorectal neoplasms detected by colonoscopy (totaling 38 neoplasms). Six of the 38 neoplasms were also detected by FDG PET/CT. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of FDG PET/CT in the detection of advanced colorectal neoplasms were 15.8% (6/38), 99.1% (1063/1073), 37.5% (6/16), 97.1% (1063/1095), and 96.2% (1069/1111) respectively. The presence of lesions with an endoscopic size ≤1.5 cm (P<0.001) and low-grade dysplasia (P<0.001) were the main predictors of false-negative FDG PET/CT findings.

Conclusions

We conclude that FDG PET/CT screening of advanced colorectal neoplasms is unwarranted, especially in the presence of lesions with an endoscopic size ≤1.5 cm or low-grade dysplasia.