New occurrence and recurrence of neoplasms within 5 years of a screening colonoscopy

The impact of surgical weight loss procedures on the risk of metachronous colorectal neoplasia: the differential effect of surgery type, sex, and anatomic location

Patients with prior colorectal polyps are at high risk for metachronous colorectal neoplasia, especially in the presence of obesity. We assessed the impact of 2 common bariatric surgeries, vertical sleeve gastrectomy and roux-n-Y gastric bypass, on the risk of colorectal neoplasia recurrence. This nationally representative analysis included 1183 postbariatric adults and 3193 propensity score-matched controls, who all had prior colonoscopy with polyps and polypectomy. Colorectal polyps reoccurred in 63.8% of bariatric surgery patients and 71.7% of controls at a mean follow-up of 53.1 months from prior colonoscopy. There was a reduced odds of colorectal polyp recurrence after bariatric surgery compared with controls (odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.58 to 0.83). This effect was most pronounced in men (OR = 0.58, 95% CI = 0.42 to 0.79), and post roux-n-Y gastric bypass (OR = 0.57, 95% CI = 0.41 to 0.79). However, the risk of rectal polyps or colorectal cancer remained consistent between groups. This study is the first to our knowledge to show a reduction in risk of polyp recurrence following bariatric surgery.

Surveillance Recommendation for Colonoscopy after Polypectomy

The incidence and mortality of colorectal cancer (CRC) have declined over the past several decades, largely due to improvement and uptake in screening, particularly with colonoscopy. The US Multi-Society Task Force on CRC published guidelines for surveillance after polypectomy in 2012, which were updated in 2020 with some important changes, and this review will provide an updated overview of evidence and outcomes of surveillance after polypectomy. Notable modifications to surveillance guidelines include increasing interval time between colonoscopies from 5 to 7 to 10 years for 1 to 2 low-risk adenomas (<10 mm) and from 3 years to 3 to 5 years when 3 to 4 low-risk adenomas are identified.

A Qualitative Transcriptional Signature for the Risk Assessment of Precancerous Colorectal Lesions

It is meaningful to assess the risk of cancer incidence among patients with precancerous colorectal lesions. Comparing the within-sample relative expression orderings (REOs) of colorectal cancer patients measured by multiple platforms with that of normal colorectal tissues, a qualitative transcriptional signature consisting of 1,840 gene pairs was identified in the training data. Within an evaluation dataset of 16 active and 18 inactive (remissive) ulcerative colitis subjects, the median incidence risk score of colorectal carcinoma was 0.6402 in active ulcerative colitis subjects, significantly higher than that in remissive subjects (0.3114). Evaluation of two other independent datasets yielded similar results. Moreover, we found that the score significantly positively correlated with the degree of dysplasia in the case of colorectal adenomas. In the merged dataset, the median incidence risk score was 0.9027 among high-grade adenoma samples, significantly higher than that among low-grade adenomas (0.8565). In summary, the developed incidence risk score could well predict the incidence risk of precancerous colorectal lesions and has value in clinical application.

Outcomes at follow-up of negative colonoscopy in average risk population: systematic review and meta-analysis

OBJECTIVE

To review and summarise the evidence on the prevalence of colorectal adenomas and cancers at a follow-up screening colonoscopy after negative index colonoscopy, stratified by interval between examinations and by sex.

DESIGN

Systematic review and meta-analysis of all available studies.

DATA SOURCES

PubMed, Web of Science, and Embase. Two investigators independently extracted characteristics and results of identified studies and performed standardised quality ratings.

ELIGIBILITY CRITERIA

Studies assessing the outcome of a follow-up colonoscopy among participants at average risk for colorectal cancer with a negative previous colonoscopy (no adenomas).

RESULTS

28 studies were identified, including 22 cohort studies, five cross sectional studies, and one case-control study. Findings for an interval between colonoscopies of one to five, five to 10, and more than 10 years were reported by 17, 16, and three studies, respectively. Summary estimates of prevalences of any neoplasm were 20.7% (95% confidence interval 15.8% to 25.5%), 23.0% (18.0% to 28.0%), and 21.9% (14.9% to 29.0%) for one to five, five to 10, and more than 10 years between colonoscopies. Corresponding summary estimates of prevalences of any advanced neoplasm were 2.8% (2.0% to 3.7%), 3.2% (2.2% to 4.1%), and 7.0% (5.3% to 8.7%). Seven studies also reported findings stratified by sex. Summary estimates stratified by interval and sex were consistently higher for men than for women.

CONCLUSIONS

Although detection of any neoplasms was observed in more than 20% of participants within five years of a negative screening colonoscopy, detection of advanced neoplasms within 10 years was rare. Our findings suggest that 10 year intervals for colonoscopy screening after a negative colonoscopy, as currently recommended, may be adequate, but more studies are needed to strengthen the empirical basis for pertinent recommendations and to investigate even longer intervals.

STUDY REGISTRATION

Prospero CRD42019127842.

Frequency and Characteristics of Interval Colorectal Cancer in Actual Clinical Practice: A KASID Multicenter Study

Background/Aims

The aims of the present study were to determine the frequency of interval colorectal cancers (CRCs) after surveillance colonoscopy and to compare the clinicopathologic features and survival outcomes with those of non-interval CRCs.

Methods

From January 2003 to December 2013, 66,016 follow-up colonoscopies for 38,412 patients performed within recommended time were reviewed retrospectively based on data from 11 tertiary hospitals in South Korea. To compare clinicopathologic features and survival rates for interval CRC, 106 patients with non-interval CRC matched in age and gender were included.

Results

Among the 66,016 colonoscopies performed within the surveillance period, 63 cases (63/66,016) of interval CRC were detected, and 53 were finally included in the analysis. The mean age was 69.9±8.8 years, and the male to female ratio was 1.94:1. Although the occurrence rate of cancer in the right side colon was higher than that of non-interval CRC, interval CRCs were predominantly left sided. Other clinicopathologic features and overall survival were not significantly different between the two groups. Missed lesion was suspected to be the most common cause (29 cases, 54.7%).

Conclusions

The frequency of interval CRC among patients who had undergone a surveillance colonoscopy was 0.095%. While sharing some similar clinical features and survival outcomes, interval CRCs in Korea developed more often in males and on the left side in contrast to results from Western studies.

Single-cell genetic analysis of clonal dynamics in colorectal adenomas indicates CDX2 gain as a predictor of recurrence

Colorectal adenomas are common precancerous lesions with the potential for malignant transformation to colorectal adenocarcinoma. Endoscopic polypectomy provides an opportunity for cancer prevention; however, recurrence rates are high. We collected formalin-fixed paraffin-embedded tissue of 15 primary adenomas with recurrence, 15 adenomas without recurrence, and 14 matched pair samples (primary adenoma and the corresponding recurrent adenoma). The samples were analysed by array-comparative genomic hybridisation (aCGH) and single-cell multiplex interphase fluorescence in situ hybridisation (miFISH) to understand clonal evolution, to examine the dynamics of copy number alterations (CNAs) and to identify molecular markers for recurrence prediction. The miFISH probe panel consisted of 14 colorectal carcinogenesis-relevant genes (COX2, PIK3CA, APC, CLIC1, EGFR, MYC, CCND1, CDX2, CDH1, TP53, HER2, SMAD7, SMAD4 and ZNF217), and a centromere probe (CEP10). The aCGH analysis confirmed the genetic landscape typical for colorectal tumorigenesis, that is, CNAs of chromosomes 7, 13q, 18 and 20q. Focal aberrations (≤10 Mbp) were mapped to chromosome bands 6p22.1-p21.33 (33.3%), 7q22.1 (31.4%) and 16q21 (29.4%). MiFISH detected gains of EGFR (23.6%), CDX2 (21.8%) and ZNF217 (18.2%). Most adenomas exhibited a major clone population which was accompanied by multiple smaller clone populations. Gains of CDX2 were exclusively seen in primary adenomas with recurrence (25%) compared to primary adenomas without recurrence (0%). Generation of phylogenetic trees for matched pair samples revealed four distinct patterns of clonal dynamics. In conclusion, adenoma development and recurrence are complex genetic processes driven by multiple CNAs whose evaluations by miFISH, with emphasis on CDX2, might serve as a predictor of recurrence.

Risk factors for metachronous colorectal cancer or polyp: A systematic review and meta-analysis

BACKGROUND AND AIM

We conducted a systematic review and meta-analysis to identify personal, lifestyle, and tumor-related risk factors for metachronous colorectal cancer (CRC) and polyp.

METHODS

Relevant studies were identified by searching MEDLINE, Web of Science and Cochrane Central Register through 15 May 2016. Estimates for associations were summarized using random effects models.

RESULTS

Fifty-five studies were included in the review. For individuals who had a CRC resection, having a synchronous polyp was a risk factor for metachronous CRC or polyp (relative risk [RR], 2.04; 95% confidence interval [CI], 1.48-2.82) and having a synchronous CRC (RR, 1.90; 95% CI, 1.25-2.91) and proximally located CRC (RR, 2.12; 95% CI, 1.24-3.64) were risk factors for metachronous CRC. For individuals who had a polypectomy, larger size (RR, 4.26; 95% CI, 2.11-8.57) or severe dysplasia of the initial polyp (RR, 5.15; 95% CI, 2.02-13.14), and having a synchronous polyp (RR, 2.52; 95% CI, 1.35-4.73) were risk factors for metachronous CRC; and a family history of CRC (RR, 1.90; 95% CI, 1.26-2.87), having a synchronous polyp (RR, 2.47; 95% CI, 1.74-3.50) and a larger size (RR, 1.49; 95% CI, 1.03-2.15) and proximal location of the initial polyp (RR, 1.20; 95% CI, 1.02-1.40) were risk factors for metachronous polyp. Meta-regression showed duration of follow-up was not a source of heterogeneity for most associations. There was no evidence that lifestyle factors were associated with metachronous CRC or polyp risk.

CONCLUSION

A comprehensive list of risk factors identified for metachronous CRC or polyp may have important clinical implications.

A Review of Outcomes for Colorectal Adenomas

OBJECTIVES

Using data from former reports, this study reviews and analyzes the outcomes of tumor recurrence, tumor progression, and tumor-specific survival of patients with colorectal adenomas.

METHODS

Data were collected from 32 longitudinal studies of outcomes after the first diagnosis of colorectal adenoma and collected as individual patient results, that is, as failure times from the first tumor to the three outcomes. Altogether, there were 45,286 patients, including 22,148 for the outcome of additional adenomas, 23,796 for the outcome of progression to invasive carcinoma, and 2,602 for the outcome of disease-specific survival (some patients were available for more than one outcome).

RESULTS

In these data, the mean time to additional adenomas was 6 years, the mean time to invasive carcinoma was 15.9 years, and the mean tumor-specific survival time was 21.9 years.

CONCLUSIONS

Although greater than 50% of those with colorectal adenomas will have additional adenomas, few progress to invasive tumor or die of colorectal cancer.

Association between the location of colon polyps at baseline and surveillance colonoscopy - A retrospective study

INTRODUCTION

Several factors are used to stratify the probability of polyp recurrence. However, there are no studies correlating the location of the initial polyps and the recurrent ones. The aim of this study was to verify whether the polyp location at the surveillance colonoscopy was correlated with the location of the previously excised polyps at the baseline colonoscopy.

METHODS

A retrospective study of patients submitted to colonoscopy with presence and excision of all polyps, followed by a surveillance colonoscopy. Polyp location was divided into proximal/distal to splenic flexure and rectum. Characteristics and recurrent rates at the same colon location were also evaluated.

RESULTS

Out of the 346 patients who underwent repeated colonoscopy, 268 (77.4%) had at least 1 polyp detected. For all the segments there was an increased risk of recurrent polyps in the same location and it was about four times higher in proximal (OR 3.5; CI 2.1-6.0) and distal colon segments (OR 3.8; CI 2.1-6.8), followed by three times higher in the rectum (OR 2.6; CI 1.5-4.6). No difference was found between the rates of recurrence at the same segment, taking into consideration the polyp morphology, size, polypectomy technique employed and histological classification.

CONCLUSION

There seems to be a significant association between polyp location at baseline and surveillance colonoscopy.

A comparison of endoscopy versus pathology sizing of colorectal adenomas and potential implications for surveillance colonoscopy

BACKGROUND AND AIMS

The aim of this study was to compare endoscopy and pathology sizing in a large population-based series of colorectal adenomas and to evaluate the implications for patient stratification into surveillance colonoscopy.

METHODS

Endoscopy and pathology sizes available from intact adenomas removed at colonoscopies performed as part of the Northern Ireland Bowel Cancer Screening Programme, from 2010 to 2015, were included in this study. Chi-squared tests were applied to compare size categories in relation to clinicopathologic parameters and colonoscopy surveillance strata according to current American Gastroenterology Association and British Society of Gastroenterology guidelines.

RESULTS

A total of 2521 adenomas from 1467 individuals were included. There was a trend toward larger endoscopy than pathology sizing in 4 of the 5 study centers, but overall sizing concordance was good. Significantly greater clustering with sizing to the nearest 5 mm was evident in endoscopy versus pathology sizing (30% vs 19%, P < .001), which may result in lower accuracy. Applying a 10-mm cut-off relevant to guidelines on risk stratification, 7.3% of all adenomas and 28.3% of those 8 to 12 mm in size had discordant endoscopy and pathology size categorization. Depending on which guidelines are applied, 4.8% to 9.1% of individuals had differing risk stratification for surveillance recommendations, with the use of pathology sizing resulting in marginally fewer recommended surveillance colonoscopies.

CONCLUSIONS

Choice of pathology or endoscopy approaches to determine adenoma size will potentially influence surveillance colonoscopy follow-up in 4.8% to 9.1% of individuals. Pathology sizing appears more accurate than endoscopy sizing, and preferential use of pathology size would result in a small, but clinically important, decreased burden on surveillance colonoscopy demand. Careful endoscopy sizing is required for adenomas removed piecemeal.

Colonoscopic surveillance after colorectal cancer resection: who needs more intensive follow-up?

BACKGROUND/AIMS

Although there are guidelines for colonoscopic surveillance after colorectal cancer (CRC) surgery, the data evaluating the effectiveness of these guidelines are limited. We determined the risk factors for metachronous neoplasia (MN) by performing annual colonoscopy examinations after curative resection.

METHODS

We performed annual colonoscopic surveillance on stage I-III CRC patients after curative resection. We stratified the patients based on the advanced neoplasia risk during the surveillance.

RESULTS

Advanced MN detected was in 59 (13.1%) of 451 patients. Overall, the cumulative incidence of advanced MN was 17.3% at 5 years. By the multivariate analysis, the risk factors for advanced MN were male gender, age >65, left-sided index cancer and being in the high-risk group. The cumulative incidence of advanced MN was 38.9% at 5 years in the high-risk group. Among the patients who had advanced MN, secondary advanced MN was detected in 13 patients (22.0%) with a subsequent colonoscopy. The 2-year cumulative incidence of secondary advanced MN was 16.9%. Four (0.88%) patients had metachronous CRC during the surveillance and the interval from the index CRC was a median of 58.5 months.

CONCLUSIONS

Although the current follow-up guidelines for colonoscopic surveillance after CRC are well established, the high-risk group calls for more meticulous follow-up, which should be continued for a sufficient time.

Novel risk stratification for recurrence after endoscopic resection of advanced colorectal adenoma

BACKGROUND

Advanced colorectal adenoma (ACA) refers to adenomas with the following predictive characteristics: ≥1 cm in diameter, and/or villous component, and/or high-grade dysplasia. ACA has high risk of transforming to colorectal cancer, and the recurrence rate is relatively high.

OBJECTIVE

To assess the outcomes of patients with ACA undergoing endoscopic resection and to identify risk factors for local recurrence and development of metachronous advanced neoplasm.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care medical center.

PATIENTS

From 2005 to 2011, the records of 3625 patients who underwent colonoscopic polypectomy at Seoul National University Hospital were retrospectively reviewed. Patients with synchronous colorectal cancers, inflammatory bowel disease, previous colorectal resection, loss to follow-up, and incomplete resection were excluded.

INTERVENTION

Endoscopic resection for ACA.

MAIN OUTCOME MEASUREMENTS

Local recurrence and metachronous advanced neoplasm.

RESULTS

The study included 917 patients with 1206 ACAs. The median duration of follow-up was 28.5 months (interquartile range, 12.8-51.7). Independent risk factors for local recurrence included ACA with 2 or more predictive characteristics (adjusted hazard ratio [HR], 2.46; 95% confidence interval [CI], 1.11-5.48; P = .027) and piecemeal resection (adjusted HR, 6.96; 95% CI, 1.58-30.71; P = .010). Independent risk factors for metachronous advanced neoplasm were male gender (adjusted HR, 1.65; 95% CI, 1.02-2.65; P = .041), ≥3 adenomas (adjusted HR, 2.56; 95% CI, 1.72-3.82; P < .001), and ≥3 ACAs (adjusted HR, 1.44; 95% CI, 1.01-2.06; P = .045).

LIMITATIONS

Retrospective design.

CONCLUSION

ACAs with 2 or more predictive characteristics recurred locally at a higher rate than ACAs with 1 predictive characteristic. These results suggest that patients who are found to have ACAs with 2 or more predictive factors at index colonoscopy are at higher risk for local recurrence, and follow-up colonoscopy should be performed sooner.

Probability of high-risk colorectal neoplasm recurrence based on the results of two previous colonoscopies

BACKGROUND

Current guidelines for the surveillance colonoscopy interval are largely based on the most recent colonoscopy findings.

AIM

We aimed to evaluate differences in the probability of high-risk neoplasm recurrence according to the two previous colonoscopy findings.

METHODS

This was a retrospective cohort study from a tertiary-care center. A total of 4,143 subjects who underwent three or more colonoscopies for screening or surveillance purposes from January 2001 to December 2011 were enrolled. We compared the probability of high-risk neoplasm detection on follow-up colonoscopies after the second colonoscopy based on risk categories in both the second and first colonoscopies.

RESULTS

At the final colonoscopy, 370 participants (8.9 %) had high-risk neoplasms. In patients with a normal second colonoscopy, the probability of high-risk neoplasm recurrence was different between those with normal, low-risk, and high-risk findings at the first colonoscopy (3.8, 6.8, and 17.7 %, respectively). The hazard ratio of a high-risk neoplasm at the final colonoscopy for patients with a normal second and low-risk first colonoscopy over a normal second and normal first colonoscopy was 3.07 (95 % CI 2.04-4.64, P < 0.001). The hazard ratio of high-risk neoplasm at the final colonoscopy for patients with a normal second and high-risk first colonoscopy over a normal second with normal first colonoscopy was 7.88 (95 % CI 4.90-12.67, P < 0.001).

CONCLUSIONS

The rate of high-risk colorectal neoplasm recurrence differs according to the two previous colonoscopy findings. Therefore, surveillance intervals could be adjusted not just only by the most recent colonoscopy findings but also by considering two previous colonoscopy findings.

Colorectal cancer screening: tests, strategies, and perspectives

Screening has a central role in colorectal cancer (CRC) control. Different screening tests are effective in reducing CRC-specific mortality. Influence on cancer incidence depends on test sensitivity for pre-malignant lesions, ranging from almost no influence for guaiac-based fecal occult blood testing (gFOBT) to an estimated reduction of 66–90% for colonoscopy. Screening tests detect lesions indirectly in the stool [gFOBT, fecal immunochemical testing (FIT), and fecal DNA] or directly by colonic inspection [flexible sigmoidoscopy, colonoscopy, CT colonography (CTC), and capsule endoscopy]. CRC screening is cost-effective compared to no screening but no screening strategy is clearly better than the others. Stool tests are the most widely used in worldwide screening interventions. FIT will soon replace gFOBT. The use of colonoscopy as a screening test is increasing and this strategy has superseded all alternatives in the US and Germany. Despite its undisputed importance, CRC screening is under-used and participation rarely reaches 70% of target population. Strategies to increase participation include ensuring recommendation by physicians, introducing organized screening and developing new, more acceptable tests. Available evidence for DNA fecal testing, CTC, and capsule endoscopy is reviewed.

Accuracy of fecal immunochemical tests for colorectal cancer: systematic review and meta-analysis

BACKGROUND

Performance characteristics of fecal immunochemical tests (FITs) to screen for colorectal cancer (CRC) have been inconsistent.

PURPOSE

To synthesize data about the diagnostic accuracy of FITs for CRC and identify factors affecting its performance characteristics.

DATA SOURCES

Online databases, including MEDLINE and EMBASE, and bibliographies of included studies from 1996 to 2013.

STUDY SELECTION

All studies evaluating the diagnostic accuracy of FITs for CRC in asymptomatic, average-risk adults.

DATA EXTRACTION

Two reviewers independently extracted data and critiqued study quality.

DATA SYNTHESIS

Nineteen eligible studies were included and meta-analyzed. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of FITs for CRC were 0.79 (95% CI, 0.69 to 0.86), 0.94 (CI, 0.92 to 0.95), 13.10 (CI, 10.49 to 16.35), 0.23 (CI, 0.15 to 0.33), respectively, with an overall diagnostic accuracy of 95% (CI, 93% to 97%). There was substantial heterogeneity between studies in both the pooled sensitivity and specificity estimates. Stratifying by cutoff value for a positive test result or removal of discontinued FIT brands resulted in homogeneous sensitivity estimates. Sensitivity for CRC improved with lower assay cutoff values for a positive test result (for example, 0.89 [CI, 0.80 to 0.95] at a cutoff value less than 20 µg/g vs. 0.70 [CI, 0.55 to 0.81] at cutoff values of 20 to 50 µg/g) but with a corresponding decrease in specificity. A single-sample FIT had similar sensitivity and specificity as several samples, independent of FIT brand.

LIMITATIONS

Only English-language articles were included. Lack of data prevented complete subgroup analyses by FIT brand.

CONCLUSION

Fecal immunochemical tests are moderately sensitive, are highly specific, and have high overall diagnostic accuracy for detecting CRC. Diagnostic performance of FITs depends on the cutoff value for a positive test result.

PRIMARY FUNDING SOURCE

National Institute of Diabetes and Digestive and Kidney Diseases and National Cancer Institute.

Dietary lifestyle and colorectal cancer onset, recurrence, and survival: myth or reality?

BACKGROUND AND PURPOSE

Interest in the possibility that diet might help to reduce the risk of colorectal cancer dates back to 1970 based on both the large variation in rates of specific cancers in different countries and the impressive changes observed in the incidence of cancer in migrants from low- to high-risk areas. Here, we report the state of art of literature data about this topic.

METHODS

Three sections have been separately considered: chemoprevention of first tumor onset, chemoprevention of recurrence after surgery, and chemoprevention of polyp recurrence in the course of the follow-up of subjects with elevated risk. A particular attention has been pointed to dietary factors and survival, whose relevance is showing a growing interest.

RESULTS

The relationship between diet and colorectal cancer has been extensively studied about the onset, sometimes with controversial results. Its influence on recurrence and survival has been examined in only few studies.

CONCLUSIONS

Literature data are convincing for a protective role on the onset of preneoplastic and neoplastic lesions for some foods such as fibers, vitamin A and D, folic acid, calcium, antioxidants, and promising perspectives for some substances such as phyto-estrogens. Less evidence-based data are available on the possibility to avoid the recurrence of the disease or to affect its mortality with dietary habits. Future perspectives will be directed be not only to identify new dietary style able to prevent the onset of neoplastic lesion of the colon but also to realize an effective chemoprevention.

Colorectal cancers occurring after colonoscopy with polyp detection: sites of polyps and sites of cancers

Colonoscopy with detection and removal of neoplasms strongly reduces risk of colorectal cancer (CRC). Nevertheless, CRCs occur after colonoscopic polypectomy. We assessed agreement beyond chance of location of polyps detected at colonoscopy and of subsequent CRCs to estimate the share of cancers that might be due to field effects or neoplasm recrudescence. In a population-based case-control study conducted in Germany (3,148 cases), detailed history and results of colonoscopies conducted within 10 years before cancer diagnosis were obtained by interview and from medical records. We determined the observed proportion of cancers for which a polyp had been detected at the same colorectal subsite at the preceding colonoscopy and compared it to the proportion expected by chance. A total of 155 cases with physician validated polyp detection at the preceding colonoscopy were identified. Among 148 cases with cancer restricted to a single subsite, 43 (29.1%) had a polyp detected in the same colorectal subsite at the preceding colonoscopy. Agreement of location of cancer occurrence and preceding polyp detection would have been expected by chance for 27 cases, and agreement beyond chance was estimated to account for 16 cases (10.8%, 95% confidence interval 2.7%-19.3%). Our study suggests that less than one of nine CRCs occurring within 10 years after colonoscopy with polyp detection may be due to field effects or polyp recrudescence.

Predictors of colorectal polyp recurrence after the first polypectomy in private practice settings: a cohort study

Background

Supplementary observational data in the community setting are required to better assess the predictors of colorectal polyp recurrence and the effectiveness of colonoscopy surveillance under real circumstances.

Aim

The goal of this study was to identify patient characteristics and polyp features at baseline colonoscopy that are associated with the recurrence of colorectal polyps (including hyperplastic polyps) among patients consulting private practice physicians.

Patients and Methods

This cohort study was conducted from March 2004 to December 2010 in 26 private gastroenterology practices (France). It included 1023 patients with a first-time diagnosis of histologically confirmed polyp removed during a diagnostic or screening colonoscopy. At enrollment, interviews were conducted to obtain data on socio-demographic variables and risk factors. Pathology reports were reviewed to abstract data on polyp features at baseline colonoscopy. Colorectal polyps diagnosed at the surveillance colonoscopy were considered as end points. The time to event was analyzed with an accelerated failure time model assuming a Weibull distribution.

Results

Among the 1023 patients with colorectal polyp at baseline, 553 underwent a surveillance colonoscopy. The mean time interval from baseline colonoscopy to first surveillance examination was 3.42 (standard deviation, 1.45) years. The recurrence rates were 50.5% and 32.9% for all polyps and adenomas, respectively. In multivariate models, the number of polyps at baseline was the only significant predictor for both polyp recurrence (hazard ratio [HR] 1.19, 95% CI 1.06 to 1.33), and adenoma recurrence (HR 1.17, 95% CI 1.03 to 1.34).

Conclusion

The efficacy of surveillance colonoscopy in community gastroenterology practice compared favorably with academic settings. This study provides further evidence that the number of initial colorectal polyps is useful for predicting the risk of polyp recurrence, even in the community setting.

Adenoma incidence decreases under the effect of polypectomy

AIM: To investigate whether, under the influence of polypectomy, the incidence of adenoma decreases with age.

METHODS: Consecutive patients with colonic adenomas identified at index colonoscopy were retrospectively selected if they had undergone three or more complete colonoscopies, at least 24 mo apart. Patients who had any first-degree relative with colorectal cancer were excluded. Data regarding number of adenomas at each colonoscopy, their location, size and histological classification were recorded. The monthly incidence density of adenomas after the index examination was estimated for the study population, by using the person-years method. Baseline adenomas were excluded from incidence calculations but their characteristics were correlated with recurrence at follow-up, using the χ² test.

RESULTS: One hundred and fifty-six patients were included (109 male, mean age at index colonoscopy 56.8 ± 10.3 years), with follow-up that ranged from 48 to 232 mo. No significant correlations were observed between the number, the presence of villous component, or the size of adenomas at index colonoscopy and the presence of adenomas at subsequent colonoscopies (P = 0.49, 0.12 and 0.78, respectively). The incidence of colonic adenomas was observed to decay from 1.4% person-months at the beginning of the study to values close to 0%, at 12 years after index colonoscopy.

CONCLUSION: Our results suggest the sporadic formation of adenomas occurs within a discrete period and that, when these adenomas are removed, all neoplasia-prone clones may be extinguished.

Colorectal cancer incidence is low in patients following a colonoscopy

BACKGROUND/AIMS

Colonoscopy has been proven a valuable tool in preventing colorectal cancer in controlled studies; we conducted a longitudinal confirmation study in everyday clinical practice.

METHODS

In a retrospective study, we monitored the outcome of patients with a total colonoscopy at our hospital between 1994 and 2007. We analysed the data of in-house follow-up colonoscopies, a national person registry and the morphological tumour registry centralizing all histopathological data at a national level. Patients with a particular colorectal cancer risk were excluded.

RESULTS

8950 patients were included in our study. 2032 (22.7%) patients had at least one colorectal adenoma at index colonoscopy. Adenoma prevalence was significantly higher in men than in women (27.9% vs. 17.4%, p<0.001) and was increasing with age in both sexes. Patients were followed for a mean of 5.2 years and 19 had invasive colorectal cancer detected over 47,725 person years of follow-up. The incidence rate was 0.40 cases/1000 person years of follow-up (95% confidence interval, 0.25-0.62), and the standardized incidence ratio was 0.37 (95% confidence interval, 0.24-0.58).

CONCLUSION

Incidence rates of colorectal cancer are low in the follow-up of patients having undergone a total colonoscopy in everyday practice. After standard therapy of colorectal adenomas at colonoscopy, there is little evidence for excess colorectal cancer incidence in this subgroup.

Metabolic syndrome is associated with increased risk of recurrent colorectal adenomas in Korean men

OBJECTIVE

Because of the high incidence of recurrent colorectal adenomas, regular surveillance by colonoscopy is recommended. However, there is still a shortage of information on the factors that influence the incidence of recurrent colorectal adenomas in patients with a history of these lesions. The aim of this study was to determine the association between the development of recurrent colorectal adenomas, metabolic syndrome and obesity.

SUBJECTS AND METHODS

The hospital-based cohort was composed of 193 patients who had recurrent colorectal adenomas removed between January 2002 and December 2003. The Cox proportional hazard model was used to determine hazard ratio (HR) and 95% confidence interval (CI) between obesity, metabolic syndrome and other factors, and the incidence of recurrent adenomatous polyps.

RESULTS

The mean follow-up period was 4.8 person-years. In all, 78 of the patients (40.4%) had recurrent colorectal adenomas. In the overall recurrent adenoma group, significant associations between metabolic syndrome (HR, 1.33; 95% CI, 1.02-1.73), waist circumference (WC) ≥ 90 cm (HR, 1.42; 95% CI, 1.06-1.90) and waist-hip ratio (WHR) ≥ 0.9 (HR, 2.03; 95% CI, 1.55-2.68) were found. Moreover, advanced adenomas were significantly associated with metabolic syndrome (HR, 2.81; 95% CI, 1.86-4.25), body mass index ≥ 25 kg m(-2) (HR, 2.69; 95% CI, 1.64-4.42), WC (HR, 2.16; 95% CI, 1.31-3.54) and WHR (HR, 1.99; 95% CI, 1.28-3.11). In addition, current smoking (HR, 2.60; 95% CI, 1.09-6.25) and alcohol consumption (HR, 2.20; 95% CI, 1.10-4.39) were also significantly associated with recurrent advanced adenoma.

CONCLUSION

Metabolic syndrome and obesity were significantly associated with the development of recurrent colorectal adenomas in Korean adult males. Furthermore, these associations were more strongly associated with advanced adenomas.

Estimated long-term effects of the initial 6 years of the German screening colonoscopy program

BACKGROUND

Colorectal cancer is the most common cancer in Germany. Screening colonoscopies have been offered as a primary screening tool in Germany since the end of 2002.

OBJECTIVE

To estimate the numbers of clinically manifest colorectal cancers prevented by detection and removal of advanced adenomas in the initial 6 years of the program.

DESIGN

Markov model with single-year transitions.

SETTING

German screening colonoscopy program.

PATIENTS

Participants in the screening colonoscopy program from 2003 to 2008.

INTERVENTIONS

Screening colonoscopy with the removal of advanced colorectal neoplasms.

MAIN OUTCOME MEASUREMENTS

The expected numbers of incident colorectal cancers prevented by detection and removal of advanced adenomas.

RESULTS

An estimated total number of 73,024 cases of colorectal cancer might have developed from the removed advanced adenomas and become clinically manifest between 55 and 84 years of age in the absence of screening colonoscopy. This number exceeds the number of colorectal cancers diagnosed in 2002 by 27%. Among prevented cancers, 8%, 43%, and 49% would have occurred at ages 55 to 64, 65 to 74, and 75 to 84 years (median age 74 years), respectively; 60% and 40% would have occurred among men and women, respectively; and 22%, 32%, 25%, and 20% would have occurred within 1 to 5, 6 to 10, 11 to 15, and 16 to 30 years, respectively, after colonoscopy (median 10 years).

LIMITATIONS

Diagnoses of advanced adenomas are based on records from a large number of endoscopists and pathology laboratories.

CONCLUSIONS

Despite relatively low screening participation, the German screening colonoscopy program is expected to make a major contribution to the prevention of colorectal cancer, even though most of the impact will only be seen in the longer run.

Colonoscopy surveillance after polypectomy may be extended beyond five years

OBJECTIVES

Colonoscopy surveillance interval data longer than 5 years are limited. We examined adenoma yield to identify factors that predict appropriate intervals for postpolypectomy surveillance greater than 5 years, including risk of advanced adenoma recurrence.

METHODS

We identified patients with and without adenomas on an index colonoscopy who returned at 5 to 10 years for a follow-up colonoscopy. Multivariate logistic regression was used to identify variables that predict finding an adenoma on follow-up colonoscopy.

RESULTS

Three hundred ninety-nine patients were identified with a follow-up colonoscopy at an interval of >5 years. Irrespective of surveillance interval, adenoma incidence occurred in 116 patients (29.1%) with 25 (6%) having advanced adenomas. Patients with nonadvanced adenomas on index colonoscopy had a similar risk of advanced adenoma on follow-up colonoscopy at 5 years versus 6 to 10 years, 5% versus 6.2% (P=0.39). The risk of advanced adenoma at 5 and 6 to 10 years in patients with a negative index colonoscopy was 7% versus 3.6% (P=0.15). Patients with an advanced adenoma at index colonoscopy had the highest rate of advanced adenoma detection at 5 years at 26%. Proximal polyp location (odds ratio 12.4, confidence interval 2.7-56.7) predicted advanced adenoma occurrence at 5 years.

CONCLUSIONS

Postpolypectomy colonoscopy intervals can be extended beyond 5 years in patients with nonadvanced adenomas. Our findings also support a rescreening interval of 5 to 10 years in patients with a negative index colonoscopy. Patients with an index advanced adenoma are at highest risk for recurrent advanced adenoma and should have repeat colonoscopy before a 5 years interval.

Polyp surveillance

Surveillance after colonic polypectomy is important to detect and remove missed synchronous polyps and cancers and new metachronous polyps or cancers. The authors review methods of surveillance and the risk of recurrent adenomas and provide surveillance recommendations.

One year recurrence of aberrant crypt foci

Aberrant crypt foci (ACF) are putative precursors of colorectal adenomas and have been postulated as a potential biomarker for colorectal cancer. Few studies have followed subjects after ACF removal to monitor recurrence. Subjects enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial were recruited for a study of ACF. A standardized protocol using magnified endoscopy and mucosal staining with methylene blue was implemented to detect rectal ACF. After removal of all baseline ACF, subjects returned 1 year later and recurrent ACF were observed and biopsied. A total of 434 of 505 (86%) subjects observed at baseline returned for the year 1 exam. The mean number of ACF at year 1 was strongly correlated with the number at baseline; subjects with 0, 1, 2 to 3, 4 to 6, and 7+ ACF at baseline had a mean of 1.2, 1.4, 1.7, 3.0, and 5.5 ACF, respectively, at year 1. ACF prevalence and mean count at year 1 (61% and 1.93, respectively), were only slightly lower than the corresponding values at year 0 (69% and 2.25, respectively). The locations of ACF at year 1 and baseline were significantly correlated. Of 96 ACF assessed for histology, 70 (73%) were hyperplastic and none were dysplastic. After removal of ACF at baseline, ACF counts 1 year later were only slightly reduced and were significantly correlated with the baseline ACF count. The results of this study do not support a role for ACF in clinical practice.

Low risk of colorectal cancer and advanced adenomas more than 10 years after negative colonoscopy

BACKGROUND & AIMS

Screening colonoscopy is an effective method to reduce the incidence of and mortality from colorectal cancer (CRC). There is little empirical evidence available about the optimal interval for screening, making this a subject of debate. We associated the prevalence of advanced colorectal neoplasms with time since negative colonoscopies.

METHODS

In a study of participants in the German colonoscopy screening program, we determined the prevalence of colorectal neoplasias detected at screening colonoscopy among subjects who had undergone a previous colonoscopy without detection of polyps (negative colonoscopy). Data were compared with that from subjects who had not received colonoscopies.

RESULTS

No CRCs were detected in participants who had a previous negative colonoscopy an average of 11.9 years previously (n = 553), compared with the 8.4 CRC cases expected based on age- and gender-specific prevalences among participants who had not received a colonoscopy (n = 2701; standardized prevalence ratio [SPR] = 0.00; 95% confidence interval [CI]: 0.00-0.55). Prevalence of advanced adenoma was also much lower among subjects who had previous colonoscopies (SPR = 0.42; 95% CI: 0.25-0.68). Adjusted prevalence ratios (95% CIs) for detecting an advanced adenoma were 0.38 (95% CI: 0.16-0.90), 0.34 (95% CI: 0.15-0.74), 0.38 (95% CI: 0.16-0.90), and 0.53 (95% CI: 0.27-1.04) among participants with a negative colonoscopy conducted 1-5, 6-10, 11-15, and >16 years ago, respectively, compared to participants with no previous colonoscopy.

CONCLUSIONS

The low risk of CRC and advanced adenomas after a negative colonoscopy supports suggestions that screening intervals be extended to > or =10 years.

Characteristics of metachronous colorectal adenomas found during long-term follow-up: analysis of four subsequent generations of adenoma recurrence

OBJECTIVE

Because of the high recurrence rates of colorectal adenomas, regular surveillance by colonoscopy has been recommended, but there is still a dearth of information on the long-term results of follow-up colonoscopy after polypectomy. The aims of this study were to determine the differences between initial adenomas and metachronous lesions, to evaluate the effect of long-term surveillance and to describe the hypothetical origin of the colorectal adenoma-carcinoma sequence.

MATERIAL AND METHODS

Between 1978 and 2003 a total of 1091 patients undergoing periodic surveillance examinations were prospectively documented at the Erlangen Registry of Colorectal Polyps. Differences between initial and metachronous lesions found during long-term follow-up were studied. Statistical analysis using chi(2) testing of adenoma characteristics found in four subsequent recurrence periods was carried out, and the relative risk (RR) for the development of metachronous adenomas of advanced pathology was calculated.

RESULTS

In comparison with the initial findings, metachronous adenomas are generally significantly smaller lesions (p<0.00001), usually tubular in shape (p<0.00001) and bearing high-grade dysplasia less often (p<0.00001) and are usually located in the right colon (p<0.00001). These differences are found between the initial and four subsequent generations of metachronous adenomas. The number of synchronous adenomas is reduced only in the first recurrence (p<0.001); in the further generations equal proportions of multiplicity are found, as in the baseline examination. Patients with adenomas of advanced pathology, i.e. large, tubulovillous or villous adenomas at baseline, have a significantly higher risk for large (RR 2.73; 95% CI 1.77-4.20), tubulovillous or villous (RR 1.55; 95% CI 1.06-2.25) or multiple (RR 2.45; 95% CI 1.83-3.29) metachronous adenomas at the first recurrence.

CONCLUSIONS

Metachronous adenomas show the uniform characteristics of being small tubular lesions rarely bearing high-grade dysplasia, usually located in the right colon. Thus regular follow-up colonoscopy can provide sufficient colorectal carcinoma prevention.

Endoscopic and histopathologic predictors of recurrence of colorectal adenoma on lowering the miss rate

BACKGROUND/AIMS

Although colorectal adenoma is reported to recur frequently, this may result from missing it at baseline. However, few studies of recurrence have considered the miss rate. This study evaluated the recurrence rate prospectively and clinical predictors of recurrence in colorectal adenoma after lowering the miss rate.

METHODS

The study population comprised 128 patients who underwent baseline colonoscopy with resection of colorectal adenomas. Re-examination to lower the miss rate was performed within 2 months. Follow-up colonoscopy to detect recurrence was done more than 1 year after removal.

RESULTS

The mean follow-up period was 35.1 months (range, 12 to 84 months). Thirty patients had a recurrent adenoma, for a recurrence rate of 23.4%. Older patients (over 60 years) had a two-fold greater risk of recurrence than younger patients (hazard ratio, 2.39; 95% confidence interval [CI], 1.16-4.90). Patients with three or four adenomas at baseline colonoscopy had a two-fold greater risk than those with one adenoma (hazard ratio, 2.44; 95% CI, 1.11-5.35). Patients with advanced adenoma had a two-fold greater risk than those with no advanced adenoma (hazard ratio, 2.88; 95% CI, 1.40-5.95). In multivariate analysis, only the presence of three or four adenomas independently predicted the recurrence of adenoma (hazard ratio, 3.19; 95% CI, 1.04-9.79).

CONCLUSIONS

The recurrence rate of colorectal adenoma corrected by lowering the miss rate was lower than reported rates. The presence of multiple adenomas on initial colonoscopy was an important predictor of recurrence.

American College of Gastroenterology guidelines for colorectal cancer screening 2009 [corrected]

This document is the first update of the American College of Gastroenterology (ACG) colorectal cancer (CRC) screening recommendations since 2000. The CRC screening tests are now grouped into cancer prevention tests and cancer detection tests. Colonoscopy every 10 years, beginning at age 50, remains the preferred CRC screening strategy. It is recognized that colonoscopy is not available in every clinical setting because of economic limitations. It is also realized that not all eligible persons are willing to undergo colonoscopy for screening purposes. In these cases, patients should be offered an alternative CRC prevention test (flexible sigmoidoscopy every 5-10 years, or a computed tomography (CT) colonography every 5 years) or a cancer detection test (fecal immunochemical test for blood, FIT).

Are many colorectal cancers due to missed adenomas?

BACKGROUND

An unknown number of colorectal cancers could be due to missed adenomas during previous endoscopy. Data in the literature are sparse. A large cross-sectional study was done in a prospective database of all patients diagnosed with colorectal cancer.

METHODS

All consecutive endoscopies over a period of 15 years, in which colorectal cancer was diagnosed were included. All patients who underwent more than one endoscopy and in whom ultimately cancer was diagnosed were studied separately.

RESULTS

Colorectal cancer was diagnosed in 835 patients. Twenty-five patients underwent a previous endoscopy without a cancer diagnosis. These 25 patients were divided into three groups according to the time between the endoscopy in which the cancer was detected and the previous endoscopy. Five out of these 25 patients underwent regular surveillance. Only 11 patients had no argument for regular follow-up. Assuming that these cancers developed from an adenoma than only 11 out of 835 (1.3%) cancers were missed in the adenoma phase. There was no difference in the size of the tumour between the three groups of patients.

CONCLUSION

In normal daily practice, only a small number of clinically important adenomas are missed. The problem of missed adenomas probably is being exaggerated.

Risk of advanced metachronous colorectal adenoma during long-term follow-up

BACKGROUND

According to the adenoma-carcinoma concept, all colorectal adenomas are to be removed and all patients have to undergo regular surveillance examinations. But there is still shortage on information on the long-term results of follow-up colonoscopy after polypectomy.

METHODS

Between 1978 and 2003, more than 20,000 polyps were prospectively documented at the Erlangen Registry of Colorectal Polyps. A total of 1,091 patients undergoing periodic surveillance examinations are studied for differences between initial and metachronous lesions of the colorectum. Statistical analysis using chi (2)-testing of adenoma characteristics found in four subsequent recurrence periods and calculation of the relative risk (RR) for the development of metachronous adenomas of advanced pathology was performed.

RESULTS

In comparison with the initial findings, metachronous adenomas are, in general, significantly smaller ones (p < 0.00001), more frequently tubular lesions (p < 0.00001) and bearing less often high-grade dysplasia (p < 0.00001). Adenomas of advanced pathology were significantly less often found during follow-up than at baseline examination (p < 0.0001). These differences are found between the initial and four subsequent generations of metachronous adenomas. Patients with adenomas of advanced pathology at baseline have a significantly higher risk for metachronous adenomas of advanced pathology (RR 1.51; 95%CI 1.04-1.93) at the first recurrence.

CONCLUSIONS

Metachronous adenomas show uniform characteristics of being small tubular lesions rarely bearing high-grade dysplasia. Thus, regular surveillance examinations can provide sufficient colorectal carcinoma prevention.

Consumption of trans-fatty acid and its association with colorectal adenomas

trans-Fatty acid consumption is known to have detrimental effects on cardiovascular health, but little is known about its role in digestive tract neoplasia. To investigate the association between colorectal adenomas and trans-fatty acid consumption, the authors utilized data from a cross-sectional study of 622 individuals who underwent complete colonoscopy between 2001 and 2002 at the University of North Carolina Hospitals. Participants were interviewed about demographic, lifestyle, and dietary factors thought to be related to colorectal cancer. trans-Fatty acid consumption, energy adjusted by the residual method, was categorized into quartiles based on its distribution in controls. Compared with participants in the lowest quartile of consumption, those in the highest quartile had an increased prevalence of colorectal adenomas, with an adjusted prevalence odds ratio of 1.86 (95% confidence interval: 1.04, 3.33). The authors further investigated the relation between trans-fatty acid consumption and colorectal neoplasia by examining the adenoma characteristics, with the adjusted prevalence odds ratios showing little or no difference by adenoma location, size, or number. These results suggest that consumption of high amounts of trans-fatty acid may increase the risk of colorectal neoplasia, and they provide additional support to recommendations to limit trans-fatty acid consumption.

Cochrane systematic review of colorectal cancer screening using the fecal occult blood test (hemoccult): an update

BACKGROUND AND AIMS

Reducing mortality from colorectal cancer (CRC) may be achieved by the introduction of population-based screening programs. The aim of the systematic review was to update previous research to determine whether screening for CRC using the fecal occult blood test (FOBT) reduces CRC mortality and to consider the benefits, harms, and potential consequences of screening.

METHODS

We searched eight electronic databases (Cochrane Library, MEDLINE, EMBASE, CINAHL, PsychINFO, AMED, SIGLE, and HMIC). We identified nine articles describing four randomized controlled trials (RCTs) involving over 320,000 participants with follow-up ranging from 8 to 18 yr. The primary analyses used intention to screen and a secondary analysis adjusted for nonattendance. We calculated the relative risks and risk differences for each trial, and then overall, using fixed and random effects models.

RESULTS

Combined results from the four eligible RCTs indicated that screening had a 16% reduction in the relative risk (RR) of CRC mortality (RR 0.84, 95% confidence interval [CI] 0.78-0.90). There was a 15% RR reduction (RR 0.85, 95% CI 0.78-0.92) in CRC mortality for studies that used biennial screening. When adjusted for screening attendance in the individual studies, there was a 25% RR reduction (RR 0.75, 95% CI 0.66-0.84) for those attending at least one round of screening using the FOBT. There was no difference in all-cause mortality (RR 1.00, 95% CI 0.99-1.02) or all-cause mortality excluding CRC (RR 1.01, 95% CI 1.00-1.03).

CONCLUSIONS

The present review includes seven new publications and unpublished data concerning CRC screening using FOBT. This review confirms previous research demonstrating that FOBT screening reduces the risk of CRC mortality. The results also indicate that there is no difference in all-cause mortality between the screened and nonscreened populations.

Apoptosis in normal rectal mucosa, baseline adenoma characteristics, and risk of future adenomas

Low apoptosis in the normal rectal mucosa has been associated with colorectal adenomas in cross-sectional studies. It is unknown whether apoptosis can predict the occurrence of new adenomas. We evaluated whether apoptosis at baseline colonoscopy, as well as patient and adenoma characteristics, could predict future occurrence of adenomas. Study subjects were participants in the Diet and Health Study III, a cross-sectional study of adenoma risk factors between August 1998 and March 2000. At baseline, subjects underwent colonoscopy and provided normal rectal mucosal biopsies to evaluate apoptosis as well as information about diet and lifestyle. The present study includes 257 subjects who returned for follow-up colonoscopy between 2000 and 2005. Apoptosis, number of adenomas, size, and atypia at baseline colonoscopy were evaluated as predictors of new adenomas. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI). At baseline, low apoptosis was significantly associated with increased risk of adenomas (P = 0.0001). Compared with those in the lowest tertile, subjects with high apoptosis were less likely to have an adenoma at follow-up (crude OR, 0.25; 95% CI, 0.09-0.65; adjusted OR, 0.29; 95% CI, 0.08-1.06). Having three or more adenomas at baseline was associated with increased risk of new adenomas (crude OR, 2.46; 95% CI, 1.14-5.31; adjusted OR, 3.74; 95% CI, 1.01-13.83). This study suggests that lower apoptosis is associated with increased risk of future adenoma development. If confirmed in larger studies, apoptosis could potentially be used to identify patients at highest risk for developing new adenomas.

Importance of postpolypectomy surveillance and postpolypectomy compliance to follow-up screening--review of literature

INTRODUCTION

Approximately 150,000 people are diagnosed with colorectal cancer each year and 56,000 may die from it annually in the United States. Colorectal cancer is the second leading cause of cancer deaths in the USA and yet, when diagnosed at an early stage, it is one of the most preventable cancers. According to the US Preventive Services Task Force, initial screening for colorectal cancer is recommended in people above 50 years of age with average risk and earlier in people with a strong family history and other risk factors. Adenomatous polyps are considered as precursors of colorectal cancer. Removal of polyps and postpolypectomy surveillance reduces the overall mortality from colorectal cancer.

DISCUSSION

According to updated guidelines in 2006, a 3-year-follow-up colonoscopy is recommended in patients with adenomatous polyps>or=1 cm. An important factor in the surveillance and prevention of colorectal cancer in postpolypectomy patients is compliance with follow-up colonoscopy. In the present article, we provide an overview of the importance of postpolypectomy surveillance and summarize the compliance data for postpolypectomy surveillance. Compliance to postpolypectomy surveillance varies from one study to another and it should be expected that the compliance with follow-up would be low outside of clinical trials. Some measures that can improve patient compliance include patient education regarding a need of follow-up screening, reminder letters, and alerts in patient's charts.

CONCLUSION

In conclusion, effective surveillance screening with good patient compliance in postpolypectomy patients will contribute significantly in reducing colon cancer morbidity and mortality.

Five-year colon surveillance after screening colonoscopy

BACKGROUND & AIMS

Outcomes of colon surveillance after colorectal cancer screening with colonoscopy are uncertain. We conducted a prospective study to measure incidence of advanced neoplasia in patients within 5.5 years of screening colonoscopy.

METHODS

Three thousand one hundred twenty-one asymptomatic subjects, age 50 to 75 years, had screening colonoscopy between 1994 and 1997 in the Department of Veterans Affairs. One thousand one hundred seventy-one subjects with neoplasia and 501 neoplasia-free controls were assigned to colonoscopic surveillance over 5 years. Cohorts were defined by baseline findings. Relative risks for advanced neoplasia within 5.5 years were calculated. Advanced neoplasia was defined as tubular adenoma greater than > or =10 mm, adenoma with villous histology, adenoma with high-grade dysplasia, or invasive cancer.

RESULTS

Eight hundred ninety-five (76.4%) patients with neoplasia and 298 subjects (59.5%) without neoplasia at baseline had colonoscopy within 5.5 years; 2.4% of patients with no neoplasia had interval advanced neoplasia. The relative risk in patients with baseline neoplasia was 1.92 (95% CI: 0.83-4.42) with 1 or 2 tubular adenomas <10 mm, 5.01 (95% CI: 2.10-11.96) with 3 or more tubular adenomas <10 mm, 6.40 (95% CI: 2.74-14.94) with tubular adenoma > or =10 mm, 6.05 (95% CI: 2.48-14.71) for villous adenoma, and 6.87 (95% CI: 2.61-18.07) for adenoma with high-grade dysplasia.

CONCLUSIONS

There is a strong association between results of baseline screening colonoscopy and rate of serious incident lesions during 5.5 years of surveillance. Patients with 1 or 2 tubular adenomas less than 10 mm represent a low-risk group compared with other patients with colon neoplasia.

Case-control study supports extension of surveillance interval after colonoscopic polypectomy to at least 5 yr

OBJECTIVE

Colonoscopy with removal of polyps may strongly reduce colorectal cancer (CRC) incidence and mortality. Recommended time intervals to surveillance colonoscopy differ between countries and have recently been extended to 5 yr or longer for the majority of cases in the United States. Whereas previous evidence is mainly based on observations of adenoma recurrence, we aimed to assess risk of CRC occurrence according to time since polypectomy.

METHODS

In a population-based case-control study conducted in Germany, detailed history and results of previous large bowel endoscopies were obtained by interview and from medical records. Risk of CRC among subjects with history of endoscopic polypectomy compared to subjects without previous large bowel endoscopy was assessed according to time since polypectomy among 454 cases with CRC and 391 matched controls.

RESULTS

Odds ratios (95% confidence intervals) of CRC up to 2 yr, 3-5 yr, and 6-10 yr after polypectomy (using subjects without previous endoscopy as reference group) were 0.16 (0.09-0.69), 0.27 (0.08-0.87), and 1.90 (0.67-5.43), respectively. Risk was significantly reduced (odds ratio 0.27, 95% confidence interval 0.10-0.77) within 5 yr even after detection and removal of high-risk polyps (3+ polyps, at least 1 polyp > or =1 cm, at least 1 polyp with villous components). Odds ratios (95% confidence intervals) for the entire 10-yr time interval following polypectomy were 0.50 (0.23-1.12) and 0.36 (0.18-0.76) for patients with recorded high-risk adenomas and other patients, respectively.

CONCLUSIONS

Our study provides empirical support for extension of the surveillance interval after colonoscopic polypectomy to at least 5 yr.

Repeat colonoscopy has a low yield even in symptomatic patients

BACKGROUND

In many regions, the demand for colonoscopy exceeds its availability. Patients undergoing repeat examinations comprise a significant proportion of those on waiting lists.

OBJECTIVE

To assess the yield of repeat colonoscopy in varied clinical settings.

DESIGN

Cohort study.

SETTING

Endoscopic database of an Australian tertiary referral hospital.

PATIENTS

Adults who had >/=2 colonoscopies between 1992 and 2004. Patients were excluded if the repeat procedure was for completion or for high-risk surveillance.

MAIN OUTCOME MEASUREMENTS

Yield for neoplasia by indication, interval to repeat examination, and appropriateness for surveillance (determined by National Australian guidelines).

RESULTS

A total of 4974 colonoscopies in 2075 patients were studied. The mean age was 63.1 years (range, 19.2-92.4 years). The mean number of examinations was 2.4 (range, 2-8), with a mean interval between examinations of 2.9 years. Colorectal cancer (CRC) was significantly more prevalent at initial colonoscopy compared with subsequent colonoscopies (7.9% vs 0.6%; prevalence ratio 14.2, 95% confidence interval [CI] 8.5-23.7, P < .001), as were advanced adenomas (15.3% vs 4.8%; prevalence ratio 3.2, 95% CI 2.6-3.9, P < .001). No CRCs were detected in symptomatic patients undergoing polyp surveillance examinations performed before the recommended interval.

LIMITATIONS

Retrospective design.

CONCLUSIONS

Yield of repeat colonoscopy is significantly lower than for initial colonoscopy, irrespective of indication. In symptomatic patients within a polyp surveillance program, the yield is negligible when a colonoscopy is performed before the recommended surveillance interval. The need for a repeat colonoscopy should be carefully considered, and patients who have never had a colonoscopy must take priority on waiting lists over those awaiting repeat examinations.

Colorectal cancers found after a complete colonoscopy

BACKGROUND & AIMS

The incidence of colorectal cancer in patients undergoing colonoscopic surveillance is higher than previously thought. A better understanding of interval cancers is needed to improve surveillance strategies. The objectives of this study were to determine whether interval colorectal cancers were associated with an inadequate earlier colonoscopy, incomplete polypectomy, or aggressive biologic behavior.

METHODS

We searched our institution's cancer registry. Interval cancers were defined as colorectal cancers that developed within 5 years of a complete colonoscopy. These were frequency matched in a 1:2 ratio to patients with sporadic cancers, which were defined as colorectal cancers diagnosed on a patient's first recorded colonoscopy. Patient, colonoscopy, and tumor characteristics of interval and sporadic cancers were compared.

RESULTS

Of the 830 colorectal cancers diagnosed during the study period, 45 patients developed an interval cancer (5.4%; 95% confidence interval, 4.1%-7.2%). Twenty-seven percent of interval cancers developed at previous polypectomy segments, and location of polypectomy segments was predictive of the location of subsequent interval cancers. Interval cancers were 3 times more likely to occur in the right colon and were smaller in size than sporadic cancers. Quality of bowel preparation, individual endoscopist, endoscopist experience, and trainee involvement were not associated with interval cancers. No difference in TNM stage at diagnosis, histologic type or grade, carcinoembryonic antigen level, or 5-year survival was found between interval and sporadic cancers.

CONCLUSIONS

Incomplete polypectomy might play an important role in the development of interval colorectal cancer. No association between other colonoscopy-related factors or tumor characteristics and interval cancers was found.

Cost-benefit analysis of screening colonoscopy in 40- to 50-year-old first-degree relatives of patients with colorectal cancer

BACKGROUND AND AIMS

As shown previously, 40- to 50-year-old first-degree relatives of patients with colorectal cancer (CRC) have significantly more colorectal adenomas than controls of the same age. Screening colonoscopy of these persons at risk between 40 and 50 years might be cost beneficial.

METHODS

We prepared a detailed cost-benefit analysis of screening colonoscopy and possible repeat endoscopies according to current expenditures for endoscopic procedures in Germany. Since screening colonoscopy is generally offered and reimbursed from 55 years on in Germany, we analysed the period between 45 and 55 years, taking an annual interest rate of 5% into account. Costs were analysed based on the results of a former study [11] depending on various participation rates in a general screening programme.

FINDINGS

Based on the available 1994 figure of about 20,000 euros for diagnosis and treatment of one cancer case, screening colonoscopy is cost beneficial when participation is high. Under a more realistic assumption of currently about 40,000 euros per cancer case, screening colonoscopy is cost beneficial in any case.

INTERPRETATION

Our data support that systematic screening colonoscopy in first-degree relatives of patients with CRC by the age of 45 years most likely demonstrates an economic benefit.

Type 2 diabetes mellitus: the impact on colorectal adenoma risk in women

OBJECTIVES

Increased risk for colorectal cancer (CRC) has been associated with type 2 diabetes. Despite several studies linking insulin resistance to increased CRC risk, there are limited data on colorectal adenoma risk in diabetic women. We hypothesized that diabetic women would have increased rates of colorectal adenomas relative to a group of nondiabetic women.

METHODS

Colorectal adenoma rates were determined in 100 estrogen-negative women with type 2 diabetes mellitus and compared with 500 nondiabetic, estrogen-negative controls. Adenomas were defined as any adenoma or advanced adenoma (villous or tubulovillous features, size >1 cm or high-grade dysplasia). A multivariate model including age, race, diabetes, hypertension, hypercholesterolemia, body mass index, and nonsteroidal anti-inflammatory drug status was used to determine the independent effects of diabetes on colorectal adenoma incidence.

RESULTS

Diabetics as compared with nondiabetics had greater rates of any adenoma (37%vs 24%, p= 0.009) and advanced adenomas (14%vs 6%, p= 0.009). Two hundred forty-five obese subjects compared with 355 nonobese subjects had a higher rate of any adenoma (32%vs 22%, p= 0.001). Obese diabetics compared with nonobese, nondiabetics had greater rates of any adenoma (42%vs 23%, p< or = 0.001) and advanced adenomas (19%vs 7%, p< or = 0.001). Multivariate analysis showed that adenomas and advanced adenomas were independently predicted by diabetes (p < 0.05) and adenomas by age.

DISCUSSION

Women with type 2 diabetes mellitus had higher rates of colorectal adenomas as compared with lean and nondiabetic women. This finding adds to the evidence that type 2 diabetes is an important factor in the progression of the adenoma-carcinoma sequence.

Incident rates of colonic neoplasia in older patients: when should we stop screening?

INTRODUCTION

Current guidelines endorse colon cancer screening every 5-10 years in patients over 50 years of age. However, there is no consensus regarding what age is appropriate to stop screening. The aim of this study was to characterize neoplasia occurrence/recurrence in a large cohort of patients > or =70 years of age undergoing colonoscopy.

METHODS

The Mayo Rochester endoscopic database was reviewed to determine the incidence of colonic neoplasia in patients > or =70 years undergoing two colonoscopies at least 12 months apart between January 1996 and December 2000. Patients were classified based on (i) age: 70-74, 75-79, > or =80 years; and (ii) polyp detection on initial examination, that is, subsequent examination for screening or surveillance.

RESULTS

Overall, 1353 patients underwent two colonoscopies at least 12 months apart (median interval 140 weeks) with removal of polyp on initial examination in 726 (53.7%) patients (surveillance cohort). On subsequent endoscopy, polyps > or =10 mm were detected in 54 (4.0%) and cancer in 13 (1.0%) patients. All age groups were well matched with respect to detection of neoplasia on index examination (P = 0.9) and polyp size on initial colonoscopy among the surveillance group (P = 0.9). Using a Cox proportional hazards model, adjusted hazard ratios (95% confidence interval [CI]) for neoplasia (polyps > or =10 mm) were: 2.0 (1.50-2.73, P < 0.0001) (surveillance vs screening), 1.33 (0.96-1.79, P = 0.08) (> or =80 vs 70-74), and 1.05 (0.78-1.38, P = 0.75) (75-79 vs 70-74). Adjusted hazard ratios for development of cancer were: 1.87 (1.03-3.97, P = 0.04) (surveillance vs screening), 1.73 (0.84-3.56, P = 0.13) (> or =80 vs 70-74), and 1.38 (0.71-2.77, P = 0.34) (75-79 vs 70-74).

CONCLUSIONS

Prior history of neoplasia remains a strong risk factor for colorectal neoplasia development in elderly patients and should be considered when deciding the need for continuing screening/surveillance. Incident neoplasia rates in a previously screened elderly population rise slowly with advancing age although cancer rates rise more sharply. Therefore, screening still retains a role in elderly patients; however, clinical judgment is still required to individualize screening practice. As the risk of competing comorbid illnesses continues to increase over time, the threshold to perform colon screening should increase accordingly.

Colorectal cancer (CRC) screening using sigmoidoscopy followed by colonoscopy: a feasibility and efficacy study on a cancer institute based population

BACKGROUND

Advanced distal neoplasia found at sigmoidoscopy could be the marker for more proximal lesions.

PATIENTS AND METHODS

In the setting of a screening clinic, subjects underwent flexible sigmoidoscopy. If no significant lesion was found, sigmoidoscopy was planned after 5 years. If an advanced neoplasia was found, colonoscopy was performed just after the first sigmoidoscopy and at 1, 3 and 5 years. If a non-advanced neoplasia was found, sigmoidoscopy was performed at 1, 3 and 5 years and followed by colonoscopy if advanced lesion was found.

RESULTS

At first screening 1704/1912 (88%) subjects had a negative sigmoidoscopy, 104 (5.4%) had an advanced neoplasia, 96 (6%) had a non-advanced neoplasia and eight (0.4%) had invasive colorectal cancer (CRC). At follow-up examinations at 1, 3 and 5 years, among 170 subjects with advanced and non-advanced neoplasia, one developed invasive CRC and 47 (31.6%), advanced neoplasia. At 5 years, among 718 first negative sigmoidoscopies, 572 (80%) were confirmed negative and 97 (14%) had advanced neoplasia. Colorectal cancer status at 5 years could be checked for interval cancers in 97% of subjects and no CRC was diagnosed in subjects who did not attend sigmoidoscopy at 5 years. Comparison of the incidence of invasive CRC to the data of registries of the Netherlands and Luxembourg suggested that the incidence of CRC was decreased by 36%-46%. Seven of the nine CRCs were Duke's A and the two others were Duke's B and C.

CONCLUSIONS

Screening with sigmoidoscopy followed by colonoscopy in case of positive sigmoidoscopy leads to substantial decreases in the incidence of CRC. Most CRCs found are at an early, curable stage of their development.

Guidelines for colonoscopy surveillance after polypectomy: a consensus update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society

Adenomatous polyps are the most common neoplastic findings discovered in people who undergo colorectal screening or who have a diagnostic work-up for symptoms. It was common practice in the 1970s for these patients to have annual follow-up surveillance examinations to detect additional new adenomas and missed synchronous adenomas. As a result of the National Polyp Study report in 1993, which showed clearly in a randomized design that the first postpolypectomy examination could be deferred for 3 years, guidelines published by a gastrointestinal consortium in 1997 recommended that the first follow-up surveillance take place 3 years after polypectomy for most patients. In 2003 these guidelines were updated and colonoscopy was recommended as the only follow-up examination, stratification at baseline into low risk and higher risk for subsequent adenomas was suggested. The 1997 and 2003 guidelines dealt with both screening and surveillance. However, it has become increasingly clear that postpolypectomy surveillance is now a large part of endoscopic practice, draining resources from screening and diagnosis. In addition, surveys have shown that a large proportion of endoscopists are conducting surveillance examinations at shorter intervals than recommended in the guidelines. In the present report, a careful analytic approach was designed to address all evidence available in the literature to delineate predictors of advanced pathology, both cancer and advanced adenomas, so that patients can be stratified more definitely at their baseline colonoscopy into those at lower risk or increased risk for a subsequent advanced neoplasia. People at increased risk have either 3 or more adenomas, high-grade dysplasia, villous features, or an adenoma 1 cm or larger in size. It is recommended that they have a 3-year follow-up colonoscopy. People at lower risk who have 1 or 2 small (<1 cm) tubular adenomas with no high-grade dysplasia can have a follow-up evaluation in 5-10 years, whereas people with hyperplastic polyps only should have a 10-year follow-up evaluation, as for average-risk people. There have been recent studies that have reported a significant number of missed cancers by colonoscopy. However, high-quality baseline colonoscopy with excellent patient preparation and adequate withdrawal time should minimize this and reduce clinicians concerns. These guidelines were developed jointly by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society to provide a broader consensus and thereby increase the use of the recommendations by endoscopists. The adoption of these guidelines nationally can have a dramatic impact on shifting available resources from intensive surveillance to screening. It has been shown that the first screening colonoscopy and polypectomy produces the greatest effects on reducing the incidence of colorectal cancer in patients with adenomatous polyps.

Incident rates of colonic neoplasia according to age and gender: implications for surveillance colonoscopy intervals

INTRODUCTION

Current guidelines endorse surveillance colonoscopy at 3 to 5 years following initial detection of neoplasia. However, individual patients' risks may vary according to age and gender. This study aimed to characterize neoplasia recurrence in a large patient cohort undergoing surveillance colonoscopy.

METHODS

All patients undergoing two colonoscopies at least 12 months apart between 1996 and 2000, with detection and removal of a polyp on the index colonoscopy, were identified using our endoscopic database to determine the incidence of colonic neoplasia. Patients were classified according to age (<50, 50-64, 65-74, > or =75 years) and gender.

RESULTS

Overall, 1803 patients underwent two colonoscopies at least 12 months apart (median interval, 140 weeks) with removal of a polyp on initial examination. Polyps > or =5 mm were detected in 334 (19%) patients and polyps > or =10 mm in 105 (6%) on subsequent endoscopy. All age and gender groups were well matched with respect to size of polyp detected on initial colonoscopy (P = 0.2). Kaplan-Meier curves and a Cox proportional hazards model demonstrated similar rates of neoplasia recurrence for all patients irrespective of age and gender.

CONCLUSIONS

Similar rates of neoplasia recurrence were observed among patients of different gender and age groups on surveillance colonoscopy. From a health resource utilization perspective, these findings support current recommendations for similar surveillance intervals for patients regardless of age and gender.

[Early diagnosis of colorectal tumors]

Colorectal cancer (CRC) is one of the most common causes of cancer mortality in Western countries. Approximately six percent of the population will develop colorectal cancer during life. Individuals older than 50 years or with a family history for colorectal tumors as well as patients with an inflammatory bowel disease have an increased risk for CRC. A significant reduction of colorectal cancer mortality can be achieved by screening of asymptomatic patients and removal of premalignant adenomatous polyp precursors. Colonoscopy is recognized as the gold standard, but in future virtual colonoscopy might be a reasonable addition. Asymptomatic individuals with an average risk for CRC should be screened from the age of 50 and then every 10 years if the examination showed no pathological findings. When the individual or family history indicate a higher risk for a colorectal neoplasia, screening should begin at the age of 40 or 10 years before the earliest tumor occurrence in the family. Families with hereditary CRC require a special surveillance.

Surveillance patterns and polyp recurrence following diagnosis and excision of colorectal polyps in a medicare population

OBJECTIVE

Study objectives were to determine surveillance and polyp recurrence rates among older, increased-risk patients who have been diagnosed and excised of colorectal polyps. The high incidence of colorectal cancers in the Medicare-eligible population, the strong evidence linking reductions in mortality from colorectal cancer by removal of colorectal polyps, and the paucity of postpolypectomy surveillance data in this population all supported the need for this study.

METHODS

This retrospective study used Medicare claims data to identify a cohort of 19,895 beneficiaries ages >/=65 years diagnosed and excised of colorectal polyps in 1994. Survival analysis was used to compute surveillance and polyp recurrence rates over 5 years. Log-rank test was used for all statistical comparisons.

RESULTS

Median time to first surveillance was 2.6 years. Surveillance rates for 1, 3, and 5 years were 17.6%, 55.8%, and 74.5%, respectively. Twenty-six percent had no surveillance event. Polyp recurrence rates for 1, 3, and 5 years were 10.9%, 38.2%, and 52.6%, respectively. Males and younger patients were more likely to undergo surveillance and showed higher polyp recurrence rates.

CONCLUSIONS

The high likelihood of polyp recurrence underscores the need for continued efforts to promote awareness of and compliance with postpolypectomy surveillance. Efforts to increase surveillance rates among individuals diagnosed with colorectal polyps and making available additional treatment options that may prevent the recurrence of polyps and/or their possible progression to colorectal cancer should help make significant progress in reaching the Healthy People 2010 goal of reducing colorectal cancer deaths by 34% by the year 2010.