Screening sigmoidoscopy and colorectal cancer mortality

Fecal Adnab-9 binding as a risk marker for colorectal neoplasia

Adnab-9 binding in colonic tissue and effluent has been associated with an increased risk for colorectal neoplasia. We investigated if fecal binding by Adnab-9 may be used as a marker for colorectal neoplasia. A fecal-Adnab-9 ELISA was performed on samples of 249 patients and colonoscopic pathology results correlated. Fecal Adnab-9 binding was seen in 63% of patients with colorectal neoplasia (59% with colorectal cancer and 83% with adenoma), 33% with inflammatory bowel disease, 0% with hyperplastic polyps and 10% of controls. We conclude that fecal Adnab-9 binding is a promising risk marker for colorectal neoplasia.

Identification of serum biomarkers for colon cancer by proteomic analysis

Colorectal cancer (CRC) is often diagnosed at a late stage with concomitant poor prognosis. Early detection greatly improves prognosis; however, the invasive, unpleasant and inconvenient nature of current diagnostic procedures limits their applicability. No serum-based test is currently of sufficient sensitivity or specificity for widespread use. In the best currently available blood test, carcinoembryonic antigen exhibits low sensitivity and specificity particularly in the setting of early disease. Hence, there is great need for new biomarkers for early detection of CRC. We have used surface-enhanced laser desorbtion/ionisation (SELDI) to investigate the serum proteome of 62 CRC patients and 31 noncancer subjects. We have identified proteins (complement C3a des-arg, α1-antitrypsin and transferrin) with diagnostic potential. Artificial neural networks trained using only the intensities of the SELDI peaks corresponding to identified proteins were able to classify the patients used in this study with 95% sensitivity and 91% specificity.

Screening for colorectal cancer with flexible sigmoidoscopy: is a 5-yr interval appropriate? A comparison of the detection of neoplasia 3 yr versus 5 yr after a normal examination

CONTEXT

The recommended interval for colorectal cancer screening with flexible sigmoidoscopy (FS) was recently lengthened from 3 to 5 yr. Direct evidence supporting the longer interval is lacking. The appropriateness of the longer interval has been questioned.

OBJECTIVE

To compare the incidence of neoplasia detected on FS in individuals who had undergone an FS either 3 yr or 5 yr after a normal examination.

DESIGN, SETTINGS, AND PATIENTS

Subjects were drawn from 5,359 individuals who underwent two FS examinations performed for colorectal cancer screening. Examinations were performed by gastroenterologists at a single academic medical center between 1987 and 2002. A total of 2,146 subjects with a normal baseline examination and a follow-up examination 3 and 5 yr later was included.

MAIN OUTCOME MEASURE

To compare the incidence of neoplasia, including advanced neoplasia, detected 3 yr versus 5 yr after a normal FS.

RESULTS

915 subjects underwent FS at 3 yr and 1,231 subjects at 5 yr after a normal examination. Neoplasia was detected in 3.2% of the 3-yr and 4.3% of the 5-yr subjects (p=0.17). No significant differences were detected in the pathology, multiplicity, or size of neoplasms between the 3- and 5-yr groups. Advanced neoplasms occurred in 0.9% (including one adenocarcinoma) of subjects at 3 yr and 1.1% of subjects at 5 yr (p=0.67).

CONCLUSIONS

Few individuals will develop rectosigmoid neoplasms 3 or 5 yr after a normal FS. The majority of neoplasms detected are low-risk lesions. A screening interval of 5 yr after a normal FS does not portend an increased risk of advanced neoplasms including cancer. This direct evidence supports the current recommendations of a 5-yr interval for colorectal cancer screening with FS.

Patterns of cancer incidence, mortality, and prevalence across five continents: defining priorities to reduce cancer disparities in different geographic regions of the world

Efforts to reduce global cancer disparities begin with an understanding of geographic patterns in cancer incidence, mortality, and prevalence. Using the GLOBOCAN (2002) and Cancer Incidence in Five Continents databases, we describe overall cancer incidence, mortality, and prevalence, age-adjusted temporal trends, and age-specific incidence patterns in selected geographic regions of the world. For the eight most common malignancies-cancers of lung, breast, colon and rectum, stomach, prostate, liver, cervix, and esophagus-the most important risk factors, cancer prevention and control measures are briefly reviewed. In 2002, an estimated 11 million new cancer cases and 7 million cancer deaths were reported worldwide; nearly 25 million persons were living with cancer. Among the eight most common cancers, global disparities in cancer incidence, mortality, and prevalence are evident, likely due to complex interactions of nonmodifiable (ie, genetic susceptibility and aging) and modifiable risk factors (ie, tobacco, infectious agents, diet, and physical activity). Indeed, when risk factors among populations are intertwined with differences in individual behaviors, cultural beliefs and practices, socioeconomic conditions, and health care systems, global cancer disparities are inevitable. For the eight most common cancers, priorities for reducing cancer disparities are discussed.

Detection of circulating CEA-IgM complexes in early stage colorectal cancer

We have recently shown that alpha fetoprotein (AFP) and squamous cell carcinoma antigen (SCCA), biomarkers associated with hepatocellular carcinoma, may be detected in patient sera as circulating immune complexes with IgM, and that assessment of serum levels of AFP-IgM and SCCA-IgM may be used for the detection of liver cancer. In this study we measured the levels of carcinoembryonic antigen (CEA) as free form (FCEA) and complexed to IgMs (CEA-IgM) in sera of patients affected by colorectal carcinoma (CRC) at different stages as well as in healthy subjects. FCEA levels were above the 5 ng/mL cutoff in 43% of CRC patients (31/72) and CEA-IgM levels were above the 200 AU/mL cutoff in 38% of CRC patients (27/72). Serum levels of CEA-IgM immune complexes (IC) and FCEA did not overlap and 64% of patients (46/72) were positive for at least one marker without compromising the detection specificity (94%). Early detection of CRC was significantly improved by CEA-IgM IC assay. CRC patients at an early stage (stage 1) had elevated CEA-IgM levels in 29% of cases (7/24), while FCEA levels were elevated in only 8% of cases (2/24). These results indicate that CEA-IgM is a complementary serological marker to FCEA which is much more sensitive for early stage CRC, and that the combination of these biomarkers may be useful in the early detection of colorectal cancer.

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.

Colorectal cancer screening and surveillance

Screening and surveillance substantially reduce both the incidence and mortality of colorectal cancer. Screening of normal-risk individuals may be accomplished by several methods, including fecal occult blood testing, fiberoptic sigmoidoscopy, double contrast barium enema, and colonoscopy. New technologies for screening are being developed, such as fecal immunochemical testing for blood,fecal DNA testing, and virtual colonoscopy. Patients at increased risk for colorectal cancer, such as those with a positive family history, previous adenomatous polyps or cancer, and inflammatory bowel disease, should be offered more intensive evaluation and surveillance.

Colorectal cancer screening: today and tomorrow

Colorectal cancer remains a disease with significant morbidity and mortality. However, the prognosis can be greatly improved with early detection. Here, we review the current screening modalities and guidelines for patients at average, moderate, and high risk for colorectal cancer. New experimental modalities are also introduced.

Colon pathology detected after a positive screening flexible sigmoidoscopy: a prospective study in an ethnically diverse cohort

OBJECTIVES

Although the association between distal neoplasia on sigmoidoscopy and proximal colonic pathology on follow-up colonoscopy has been well-described, it is not known if these findings are consistent across ethnic groups. The aim of this study was to evaluate ethnic variations in the prevalence of proximal neoplasia on follow-up colonoscopy after a neoplastic lesion is found on sigmoidoscopy.

METHODS

Consecutive asymptomatic patients at average-risk for colorectal cancer who were referred for screening flexible sigmoidoscopy were prospectively enrolled. Colonoscopy was recommended for all patients with a polyp on flexible sigmoidoscopy, regardless of size. Advanced neoplasms were defined as adenomas > or = 10 mm in diameter or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or cancer.

RESULTS

Among the 2,207 patients who had sigmoidoscopy, 970 were Caucasian, 765 were African American, 395 were Hispanic, and 77 were Asian. The prevalence of neoplasia in the distal colon was 12.6% in Caucasians, 11.2% in African Americans, 15.9% in Hispanics, and 24.7% in Asians (p = 0.002). Of the 290 patients with neoplastic lesions on sigmoidoscopy, follow-up colonoscopy identified neoplasms in the proximal colon in 63.9% of Caucasians, 59.3% of African Americans, 66.7% of Hispanics, and 26.3% of Asians (p = 0.01). Advanced neoplasms in the proximal colon were highest in African Americans (34.9%) and lowest in Asians (10.5%).

CONCLUSIONS

In our study population, Asians demonstrated a higher prevalence of distal colonic neoplasia and a lower prevalence of proximal colonic neoplasia compared to non-Asians. Future studies should explore ethnic variation in colonic neoplasia prevalence and location since ethnic variation could lead to tailored colorectal cancer screening strategies.

Gastroenterologists utilize the referral for EGD to enhance colon cancer screening more effectively than primary care physicians

BACKGROUND

Colorectal cancer screening rates among patients with upper gastrointestinal symptoms undergoing oesophagogastroduodenoscopy have not been previously established. We hypothesize that gastroenterologists seize this opportunity more frequently than primary care providers.

AIMS

To assess colorectal cancer screening rates at the time of direct access oesophagogastroduodenoscopy and gastrointestinal clinic evaluation for upper gastrointestinal symptoms. To compare rates in the 6 months following the oesophagogastroduodenoscopy in both cohorts of patients.

METHODS

Retrospective review. primary care physician group: direct access oesophagogastroduodenoscopy (n = 247) vs. gastrointestinal group (n = 278). Multivariable regression analysis utilized to assess predictors of screening outcome.

RESULTS

Colorectal cancer screening at the time of referral was 54%. Among the 243 unscreened patients, an additional 29% in the primary care physician group vs. 59% in the gastrointestinal group completed colorectal cancer screening in 6 months of follow-up. Nearly 60% patients evaluated in gastrointestinal clinic for upper symptoms had documented discussion, and 99% of those patients underwent colonoscopy (P < 0.001). Gastrointestinal consultation increased the probability of colorectal cancer screening completion eightfold (95% CI 3.69-18.96).

CONCLUSIONS

At the time of evaluation for upper symptoms, half of patients were not current with colorectal cancer screening recommendations. Referrals for the direct access oesophagogastroduodenoscopy and, more importantly, the gastroenterology consult represent key opportunities for colorectal cancer screening education and improved compliance.

Review in depth and meta-analysis of controlled trials on colorectal cancer screening by faecal occult blood test

BACKGROUND

Several randomized studies have shown that colorectal cancer (CRC) screening by faecal occult blood test (FOBT) reduces CRC mortality. These trials have different designs, especially concerning FOBT frequency and duration, as well as the length of follow-up after stopping FOBT campaigns.

AIMS

To review the effectiveness of screening for CRC with FOBT, to consider the reduction in mortality during or after screening or to identify factors associated with a significant mortality reduction.

METHODS

A systematic review of trials of FOBT screening with a meta-analysis of four controlled trials selected for their biennial and population-based design. The main outcome measurements were mortality relative risk (RR) and 95% confidence interval (CI) of biennial FOBT during short (10 years, i.e. five or six rounds) or long-term (six or more rounds) screening periods, as well as after stopping screening and follow-up during 5-7 years. The meta-analysis used the Mantel-Haenszel method with fixed effects when the heterogeneity test was not significant, and used 'intent to screen' results.

RESULTS

Although the quality of the four trials was high, only three were randomized, and one used rehydrated biennial FOBT associated with a high colonoscopy rate (28%). A meta-analysis of mortality results showed that subjects allocated to screening had a reduction of CRC mortality during a 10-year period (RR 0.86; CI 0.79-0.94) although CRC mortality was not decreased during the 5-7 years after the 10-year (six rounds) screening period, nor in the last phase (8-16 years after the onset of screening) of a long-term (16 years or nine rounds) biennial screening. Whatever the design of the period of ongoing FOBT, CRC incidence neither decreased nor increased, although it was reduced for 5-7 years after the 10-year screening period. Neither the design nor the clinical or demographic parameters of these trials were independently associated with CRC mortality reduction.

CONCLUSION

Biennial FOBT decreased CRC mortality by 14% when performed over 10 years, without evidence-based benefit on CRC mortality when performed over a longer period. No independent predictors of CRC mortality reduction have been identified in order to allow a CRC screening programme in any subgroups of subjects at risk.

History of negative colorectal endoscopy and risk of rectosigmoid neoplasms at screening flexible sigmoidoscopy

BACKGROUND AND AIMS

Screening sigmoidoscopy can reduce incidence of colorectal cancer and mortality. The optimal re-screening interval has not yet been defined. This study is aimed at estimating the risk of distal advanced adenomas (diameter >/=10 mm, villous component >20%, high-grade dysplasia) and cancer at screening flexible sigmoidoscopy in subjects aged 55-64 years who reported pre-screening negative colorectal endoscopy.

PATIENTS

Eight thousands two hundred two subjects aged 55-64 years who underwent screening flexible sigmoidoscopy within the SCORE trial in Italy and who were able to report their previous history of colorectal endoscopy.

RESULTS

Eight hundred eighty three of 8,202 subjects (10.8%) reported at least one prescreening negative endoscopy: among them, after 3-5 years, 6-10 years and >10 years intervals between last reported examination and screening endoscopy, the Absolute Risk of advanced adenomas was 1.5%, 0.9% and 0.9%; one cancer was detected (0.1%). Among the 7,319 subjects who did not report prescreening endoscopy the risks of advanced adenoma and cancer were 3.2% and 0.4%, respectively. Subjects with a previous colorectal examination had a 65% decreased risk of advanced adenomas (OR=0.35, 95%CI 0.18-0.66) and a 71% decreased risk of cancer (OR=0.29, 95%CI 0.04-1.12) as compared to those who did not. For subjects without family history of colorectal cancer the statistically significant decrease of the risk persisted up to ten years. The observed benefit seems not to apply to subjects with family history of colorectal cancer.

CONCLUSIONS

Our results are consistent with the hypothesis that the interval between screening sigmoidoscopies could be safely expanded beyond 5 years for subjects without specific risk factors for colorectal cancer.

Factorial validity and invariance of a survey measuring psychosocial correlates of colorectal cancer screening among African Americans and Caucasians

BACKGROUND

Psychosocial constructs are widely used to predict colorectal cancer screening and are targeted as intermediate outcomes in behavioral intervention studies. Reliable and valid instruments for measuring general colorectal cancer screening psychosocial constructs are needed; yet, few studies have conducted psychometric analyses. This study replicated a five-factor structure for 16 theory-based, general colorectal cancer screening items measuring salience and coherence, cancer worries, perceived susceptibility, response efficacy, and social influence. In addition, we examined factorial invariance across race and sex.

METHODS

African American and Caucasian patients (n = 1,413) attending an urban, primary care clinic were included in this study. These individuals completed a baseline survey as part of a colorectal cancer screening intervention trial. Single and multigroup confirmatory factor analyses using maximum-likelihood estimation were done.

RESULTS

The five-factor general colorectal cancer screening model provided excellent fit and was invariant across race-sex subgroups.

CONCLUSIONS

The findings of invariance across sex and race subgroups support the use of these scales to measure group differences.

Secondary prevention of cancer

OBJECTIVES

To review criteria for mass cancer screening among asymptomatic populations and barriers to secondary prevention of breast, cervical, and colorectal cancers. To describe challenges to implementing theoretically based interventions to increase appropriate cancer screening, follow-up, and surveillance.

DATA SOURCES

Published journal articles, text books, and epidemiologic reports.

CONCLUSION

Interventions to increase breast, cervical, and colorectal cancer screening participation must be approached from a systems perspective that includes patient, health care provider, and health care system variables.

IMPLICATIONS FOR NURSING PRACTICE

Understanding the array of factors that impede progress in the secondary prevention of cancer is necessary to improve care. Nurses have an important role in decreasing morbidity and mortality from breast, cervical, and colorectal cancers.

Colorectal cancer screening awareness in European primary care

BACKGROUND

Adjustment for stage at diagnosis markedly reduces USA versus European colorectal cancer survival differences and a screening bias was therefore suspected. Moreover, little is known about colorectal cancer screening habits in European primary care and the history of guidelines implementation. The purpose of the study was to index the overall colorectal cancer screening attitudes of European physicians involved in primary care activities.

METHODS

A systematic literature-search was performed in three major medical libraries: PubMed/MEDLINE, ISI web of science, and COCHRANE.

RESULTS

We found only five eligible studies, but valuable data were presented only in four. Colorectal cancer screening was recommended by 65-95% of physicians, but the major part of them implemented it only among high-risk individuals; stool occult blood testing was advised by 42-83% and prescription of screening endoscopic modalities was inconsistent. Most European reports found were not eligible and were mainly focused on diagnostic delay in symptomatic subjects rather than on screening procedures among asymptomatic individuals.

CONCLUSION

In comparison with European practice, colorectal cancer screening habits of American physicians are to a greater extent rational, evidence-based and well monitored and have a longer tradition in medical care thus allowing better prevention services for asymptomatic individuals.

Primary care patients' understanding of colorectal cancer screening

PURPOSE

To determine the current level of awareness and understanding about colorectal cancer (CRC) and colorectal cancer screening (CRCS) among primary care patients in order to develop interventions to educate patients about options for CRCS, help them identify CRCS preferences and make informed choices about CRCS options.

METHODS

During the spring of 2001 and 2003, two sets of focus groups with primary care patients were conducted at a large multi-specialty group practice in Houston, Texas.

RESULTS

Participants (n = 42) in both sets of focus groups had low knowledge about CRC and expressed fear and embarrassment about CRC and CRCS. Attitudes towards the fecal occult blood test (FOBT) were mixed, with some participants considering it difficult to finish and others preferring the privacy it afforded. Some participants initially failed to recognize the difference between sigmoidoscopy (SIG) and colonoscopy (COL), and several endoscopy-specific barriers were identified such as fear of pain, embarrassment/humiliation, and dislike or fear of test preparation. Some participants felt that endoscopy was likely to be more effective than FOBT, and others clearly preferred COL to SIG. System-specific barriers to endoscopy (e.g. difficulty scheduling appointments and insurance coverage) were also identified. We found little change in the barriers reported by primary care patients, despite a two-year difference between focus groups. Participants also provided suggestions for improving CRCS including telephone, letters and/or email reminders from the clinic, videotapes and websites.

CONCLUSIONS

Future interventions focused on improving informed decision-making by educating primary care patients about the risks and benefits of specific test options and about the importance of early detection of CRC could prove to be effective for increasing CRCS.

The case for direct colonoscopy screening for colorectal cancer

Recent large series of direct colonoscopy screening for colorectal cancer increase our understanding of the advantages of this approach, and have indirectly confirmed efficacy. When performed by well-trained, experienced endoscopists, colonoscopy screening is successful and safe. The prevalence of advanced neoplasia is low under the age of 50 yr but increases substantially with each decade of life thereafter at least until the age of 80 yr. Most detected cancers are at an early, curable stage. A substantial number of proximal advanced neoplasia are detected that would be missed by screening flexible sigmoidoscopy. Widespread population-based colonoscopy screening would markedly decrease the incidence and mortality of this major malignancy. Issues of compliance and capacity related to direct colonoscopy have not yet been adequately addressed.

Emerging technologies in colorectal cancer screening

CRC is a preventable disease through early detection, yet screening rates remain low and mortality rates remain high. The discomfort associated with the preparation and performance of some of the currently available screening modalities and the lack of public awareness about CRC and screening procedures likely account for low rates of screening. CT colonography and stool DNA testing are new promising screening technologies that are less invasive, accurate, and suitable for the public more than the current screening procedures. Before both tests can be promoted for population-based screening programs, several issues that have been detailed in this article must be addressed further, including technical improvements for improving accuracy, development of virtual preparation, test availability, patient and provider acceptability and cost-effectiveness for CTC, and identifying the optimal combination of molecular targets for stool DNA testing. The year 2005 will tell us if the ideal technology from the public health point of view was achieved. A skill-independent, anesthesia-free, self-propelling, self-navigating miniaturized endoscopic device that may move along the entire length of the colon may change the natural history of CRC. We should aim to achieve a new definition of CRC--a rare disease occurring in a subset of the population who has not been screened for the disease.

Screening of colorectal cancer

Cost-effectiveness analyses have shown that the cost per year of life saved by screening with any of the tests recommended is reasonable by US standards. Although the specific results vary among analyses, in general the marginal cost-effectiveness of this screening is less than $25,000 per year of life saved. Screening for CRC was among the highest ranked services in an analysis of the value of preventive services based on the burden of disease prevented and cost-effectiveness. Although the up-front costs vary by screening modality, the long-term cost-effectiveness is similar across screening tests, so that decisions about which options to include--in the long run and from the perspective of society--do not need to be affected heavily by costs. Costs increase out of proportion to benefits with shorter intervals between screening examinations. Screening has provided great opportunities. Screening can prevent CRC by polypectomy and find early-stage cancers for treatment with less morbidity. Screening can reduce the burden of treating advanced cancers and can identify families at increased risk. Screening also has provided a better understanding of the biology of CRC. Screening for CRC should be part of a complete prevention program that includes a healthy lifestyle and familial risk assessment. Individuals with increased familial risk require special screening approaches, whereas individuals with average risk can have more standard screening. The average-risk individuals can be stratified further into persons who require intensive follow-up and persons who require less intensive or no follow-up at all. We are beginning to learn how to apply screening and surveillance approaches based on risk stratification for a more cost-effective approach to conserve resources and reduce complications and costs. Chemoprevention can be added to the program when substantial benefit of agents has been demonstrated. We have a better understanding of the biology of CRC and the technology to intervene in that biology to make a difference in the lives of many people. We have the concepts and technology to reduce substantially the mortality for CRC and even prevent it entirely. Newer screening tests or others yet to be developed may, with time, replace the modern options. Screening should take place with the tests currently available and not wait until something better comes along. In this way, needless suffering and loss of life can be avoided for this leading cause of cancer death. Screening may become even more successful if the promise of new technologies is confirmed and they enter clinical practice. In the last analysis, the best test is the one that gets done and gets done immediately.

Screening of colorectal cancer: progress and problems

Considerable progress has been made in the past three decades in our understanding of the biology and prevention of colorectal cancer. The long natural history of colorectal cancer as it evolves from adenomatous polyps in the majority of cases provides opportunities for detection of early stage cancer and for prevention of cancer by removal of adenomas. Strong evidence of the effectiveness of screening has resulted in a worldwide consensus, as reported in evidence-based guidelines, that screening should be offered to all men and women age 50 and older, younger in the presence of factors that increase risk. Several options are now available for screening, and the emerging technology of stool DNA testing and virtual colonoscopy shows promise. However, many problems remain to be addressed. Screening rates are low. Successful strategies need to be implemented to overcome patient and system barriers. Resources, especially endoscopic capacity, may be inadequate to handle the burden of screening, diagnosis, and follow-up surveillances. There are quality-control issues at every step. Stratification of people by risk, a two-stage screening approach and less intensive surveillance following polypectomy can be helpful. Colorectal cancer screening is cost-effective and could save many lives each year if it were widely implemented.

How much can current interventions reduce colorectal cancer mortality in the U.S.?

BACKGROUND

Although colorectal cancer (CRC) is the second leading cause of cancer death in the U.S., available interventions to reduce CRC mortality are disseminated only partially throughout the population. This study assessed the potential reduction in CRC mortality that may be achieved through further dissemination of current interventions for risk-factor modification, screening, and treatment.

METHODS

The MISCAN-COLON microsimulation model was used to simulate the 2000 U.S. population with respect to CRC risk-factor prevalence, screening use, and treatment use. The model was used to project age-standardized CRC mortality from 2000 to 2020 for 3 intervention scenarios.

RESULTS

Without changes in risk-factor prevalence, screening use, and treatment use after 2000, CRC mortality would decrease by 17% by the Year 2020. If the 1995 to 2000 trends continue, then the projected reduction in mortality would be 36%. However, if trends in the prevalence of risk-factors could be improved above continued trends, if screening use increased to 70% of the target population, and if the use of chemotherapy increased among all age groups, then a 49% reduction would be possible. Screening drove most (23%) of the projected mortality reduction with these optimistic trends; however, decreasing risk-factors (16%) and increasing use of chemotherapy (10%) also contributed substantially. The contribution of risk-factors may have been overestimated, because effect estimates could not be obtained from randomized controlled trials.

CONCLUSIONS

Currently available interventions for risk-factor modification, screening, and treatment have the potential to reduce CRC mortality by almost 50% by the Year 2020. However, without action now to further increase the uptake of current effective interventions, the reduction in CRC mortality may be only 17%.

Physician and patient influences on the rate of colorectal cancer screening in a primary care clinic

BACKGROUND

Colorectal cancer (CRC) screening rates remain low, despite widespread recommendations. The study purpose was to ascertain whether lack of CRC screening is attributable to physicians' failure to address CRC screening or to patients' failure to comply with physician recommendation. This relationship was also examined over time.

METHODS

Retrospective chart review of 400 preventive health visits.

RESULTS

Physicians appropriately addressed screening 16.5% of the time during 1998-1999 and 51% of the time during 2002-2003 (P <or= .001). The rate of test completion by patients was 53% in 1998-1999 and 31% in 2002-2003, resulting in completed CRC screening rates of 5% and 16.5%, respectively (P <or= .001).

CONCLUSIONS

Further education is needed, especially to target patient barriers to CRC screening test completion.

Relationship of communication and information measures to colorectal cancer screening utilization: results from HINTS

Utilization of colorectal cancer screening tests is suboptimal. Knowledge of colorectal cancer screening has been associated with completion of screening. Thus, increasing awareness of colorectal cancer screening may lead to significant improvements in screening rates. We assessed for the association among provider-patient interaction, information-seeking patterns, sources of information, trust in cancer information, and Internet usage on colorectal cancer screening behavior using data obtained by the Health Information National Trends Survey (HINTS). From a cohort of 2,670 respondents greater than 50 years of age, we found that they (1) desired cancer information from personalized reading materials, meeting in person with a health care professional, and published materials; and (2) had great trust of information from their provider. Having trust in cancer information from the doctor or other health care professional was most predictive (OR 2.08, 95% CI 1.49-2.94) of being up to date. Other predictive factors include having a desire for cancer information from personalized reading materials (OR 1.56, 95% CI 1.24-1.95) and using the Internet from home (OR 1.32, 95% CI 1.04-1.67). We conclude that personalized communications from a health care provider are desired and trusted. Another promising information delivery approach is the Internet. Dedicated efforts using these approaches for information exchange may be most beneficial toward increasing utilization of colorectal cancer screening.

Using focus groups to develop interventions to promote colorectal cancer screening among Vietnamese Americans

BACKGROUND

Colorectal cancer is the third most common cancer in Vietnamese Americans. Their colorectal screening rates are lower than the rates of whites.

METHODS

Four focus groups were conducted to identify Vietnamese American sources and credibility of health information, media utilization, and intervention approaches.

RESULTS

Vietnamese Americans trusted doctors and patient testimonials and had access to, and received most of their health information from, Vietnamese- language print and electronic media. Recommended intervention approaches include promoting doctors' recommendation of screening and using Vietnamese-language mass media, print materials, and oral presentations.

CONCLUSIONS

Focus groups are useful in determining communication channels and intervention approaches.

Screening Practices of Patients Presenting for Resection of a Colorectal Neoplasm

Multiple studies demonstrate the efficacy of colorectal cancer (CRC) screening in patients over 50 years of age. However, there is a lack of consensus regarding which screening method to use, and compliance has been poor. The objective of this study was to identify the CRC screening practices at two institutions and determine the relationship between screening and pathologic stage for patients presenting with a colorectal neoplasm. This study, conducted at the University of Virginia (UVA) Health System and the Salem Veterans Affairs Medical Center (VAMC) between October 30, 2000, and September 1, 2004, included 198 patients ≥50 years who presented for resection of a primary colorectal neoplasm. Pathologic stage and prior screening were identified retrospectively through chart review and patient response to an anonymous survey. Prior screening was demonstrated in 71 per cent of patients. Colonoscopy was the most commonly used modality. There was a higher percentage of CRC screening at VAMC compared with UVA (80% vs 62%, P < 0.0008). Patients at UVA were more likely screened with colonoscopy, whereas fecal occult blood testing (FOBT) was most common at VAMC (P < 0.0001). Prior CRC screening and cancer stage were inversely related. Ninety-one per cent of patients with benign polyps had been screened prior to diagnosis, compared with 72 per cent of patients with stage I and II cancer and 54 per cent of patients with stage III and IV cancer (P < 0.05). Of patients presenting for surgery, 71 per cent underwent CRC screening. Variability exists in the methods employed for CRC screening. CRC screening facilitates diagnosis at an early stage.

Review article: Population screening for colorectal cancer

Colorectal cancer is a common cancer and common cause of death. The mortality rate from colorectal cancer can be reduced by identification and removal of cancer precursors, adenomas, or by detection of cancer at an earlier stage. Pilot screening programmes have demonstrated decreased colorectal cancer mortality; as a result many countries are developing colorectal cancer screening programmes. The most common modalities being evaluated are faecal occult blood testing, flexible sigmoidoscopy and colonoscopy. Implementation of screening tests has been hampered by cost, invasiveness, availability of resources and patient acceptance. New technologies such at computed tomographic colonography and stool screening for molecular markers of neoplasia are in development as potential minimally invasive tools. This review considers who should be screened, which test to use and how often to screen.

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.

Flexible sigmoidoscopy for colorectal cancer screening in the elderly

Data on performance characteristics of flexible sigmoidoscopy (FS) between age groups are limited. This study evaluates screening FS in subjects > or = 75 years of age (elderly) compared with ages 50-74 years (general screening population). Data were collected on patient characteristics, insertion depth, procedural difficulties, complications, and endoscopic findings. There was an increased rate of endoscopist-reported limitations (50.4% vs. 34.9%; P = 0.0001) and incomplete examinations (15.6% vs. 5.4%; P = 0.0001) in the elderly cohort relative to subjects aged 50-74. The complication rate (1.0% vs. 1.5%; P = 0.53), adenoma detection rate (7.2% vs. 5.6%; P = 0.213), and advanced adenoma detection rate (0.71% vs 0.65%; P = 0.86) were similar. More carcinomas were detected in the elderly (0.53% vs. 0.06%; P = 0.042). Factors associated with incomplete examinations in the elderly included age, female gender, and poor bowel preparation. Despite technical difficulties, FS in the elderly is safe and detects significant pathology.

Association between colonic screening, subject characteristics, and stage of colorectal cancer

OBJECTIVES

Colorectal cancer remains a significant cause of mortality and morbidity in North America. Colorectal cancer survival is highly dependent on stage at diagnosis, therefore it is important to identify factors related to stage. This study evaluated the association between subject factors (e.g., colonic screening, family history) and stage of colorectal cancer at diagnosis.

METHODS

Population-based colorectal cancer cases recruited by the Ontario Familial Colon Cancer Registry between 1997 and 1999 were staged according to the tumor-nodal-metastasis (TNM) staging system and classified as early (TNM I/II) or late (TNM III/IV) stage. Epidemiologic information and stage was available for 768 cases. Multivariate logistic regression was used to obtain odds ratios (OR) estimates.

RESULTS

Having had screening endoscopy reduced the risk of late stage diagnosis (OR = 0.46, 95% CI 0.22-0.98). Being older (>45 yr) was associated with a reduced risk of late stage cancer (OR = 0.36, 95% CI 0.18-0.74), as was having a first degree relative with colorectal cancer (OR =0.66, 95% CI 0.46-0.95). Rural residence (OR = 1.48, 95% CI 1.01-2.17) and non-white ethnicity (OR = 3.34, 95% CI 1.20-9.36) were associated with an increased risk of late stage cancer.

CONCLUSIONS

Several factors are independently associated with late stage colorectal cancer. Colorectal cancer screening awareness and education programs need to consider targeting persons most likely to present with late stage colorectal cancer.

Knowledge and perceptions of colorectal cancer screening among urban African Americans

OBJECTIVE

To explore colorectal cancer (CRC) screening knowledge, attitudes, barriers, and preferences among urban African Americans as a prelude to the development of culturally appropriate interventions to improve screening for this group.

DESIGN

Qualitative focus group study with assessment of CRC screening preferences.

SETTING

Community health center serving low-income African Americans.

PARTICIPANTS

Fifty-five self-identified African Americans over 40 years of age.

MEASUREMENTS AND MAIN RESULTS

Transcripts were analyzed using an iterative coding process with consensus and triangulation on final thematic findings. Six major themes were identified: (1) Hope--a positive attitude toward screening, (2) Mistrust--distrust that the system or providers put patients first, (3) Fear--fear of cancer, the system, and of CRC screening procedures, (4) Fatalism--the belief that screening and treatment may be futile and surgery causes spread of cancer, (5) Accuracy--a preference for the most thorough and accurate test for CRC, and (6) Knowledge--lack of CRC knowledge and a desire for more information. The Fear and Knowledge themes were most frequently noted in transcript theme counts. The Hope and Accuracy themes were crucial moderators of the influence of all barriers. The largest number of participants preferred either colonoscopy (33%) or home fecal occult blood testing (26%).

CONCLUSIONS

Low-income African Americans are optimistic and hopeful about early CRC detection and believe that thorough and accurate CRC screening is valuable. Lack of CRC knowledge and fear are major barriers to screening for this population along with mistrust, and fatalism.

Comparing risks and benefits of colorectal cancer screening in elderly patients

BACKGROUND & AIMS

In patients with limited life expectancy, the risks of colorectal cancer screening may outweigh the benefits. The aim of this study was to quantify risks and benefits of different screening strategies in elderly patients with varying life expectancies.

METHODS

We examined risks and benefits of screening in patients aged 70-94 years with differing health status using 3 strategies: annual fecal occult blood tests, flexible sigmoidoscopy every 5 years, or colonoscopy every 10 years. We compared the number needed to screen to prevent one cancer-related death and the number needed to encounter one screening-related complication for different strategies.

RESULTS

The potential benefit from screening varied widely with age, life expectancy, and screening modality. One cancer-related death would be prevented by screening 42 healthy men aged 70-74 years with colonoscopy, 178 healthy women aged 70-74 years with fecal occult blood tests, 431 women aged 75-79 years in poor health with colonoscopy, or 945 men aged 80-84 years in average health with fecal occult blood tests. Colonoscopy screening had the greatest benefit but the highest risk of complications. The potential for screening-related complications was greater than estimated benefit in some population subgroups aged 70 years and older. At all ages and life expectancies, the potential reduction in mortality from screening outweighed the risk of colonoscopy-related death.

CONCLUSIONS

The potential benefits and risks of screening vary in elderly patients of different life expectancies. For any individual patient, the potential for harm from screening must be weighed against the likelihood of benefit, especially with shorter life expectancy.

Literacy and knowledge, attitudes, and behavior about colorectal cancer screening

This cross-sectional survey explored the association between functional health literacy and knowledge of, beliefs and attitudes about, and reported usage of colorectal cancer screening tests. The results indicate that functional health literacy, as assessed by the Short Test of Functional Health Literacy in Adults (STOFHLA), is not an independent predictor of colorectal cancer screening knowledge, beliefs, attitudes, or behavior. Latino ethnicity and education, however, often predicted screening responses, suggesting that efforts to improve communication about colorectal cancer screening with Latino patients and patients with low education clearly are needed to reduce the disparities in awareness and utilization of colorectal cancer screening tests. This study also explored influences on intended screening behavior. Physician recommendation was found to be a powerful motivator of intention to undergo colorectal cancer screening regardless of literacy level, indicating that interventions aimed at increasing physician recommendation of colorectal cancer screening may be an effective way of increasing screening rates.

Colorectal cancer screening in average risk individuals

Colorectal cancer is the third leading type of cancer, and the second leading cause of cancer-related death in the United States. Prevention of colorectal cancer should be achievable by screening programs that detect adenomas in asymptomatic patients and lead to their removal. In this manuscript, we review the major screening modalities, the advantages and disadvantages of each approach, the data supporting their use, and various issues affecting the implementation of each test. Screening guidelines will be reviewed, and future techniques for colorectal cancer screening examined.

Impact of a family history of colorectal cancer on age at diagnosis, anatomic location, and clinical characteristics of colorectal cancer

BACKGROUND

Among the risk factors for colorectal cancer (CRC) is a family history of colorectal cancer. Reliable evidence is needed regarding the clinical characteristics of cancer in patients with this history to determine if a change in the diagnostic approach is needed.

AIM OF THE STUDY

This study set out to determine specific clinical outcomes in patients with CRC with a family history of one first-degree relative with sporadic colorectal cancer compared to control patients with colorectal cancer but without the family history.

METHODS

We designed a case-control study of colorectal cancer registry data between 1988 and 1999. Patients with a family history of one first-degree relative with colorectal cancer were compared to those without the history with regard to four characteristics: age at cancer diagnosis, anatomic location of the cancer, presence of distal adenomas with proximal cancer, and stage of disease at diagnosis.

RESULTS

Nine hundred and twenty-one patients met the inclusion criteria. Family history was positive in 124 patients. The demography of the populations was similar, except for mean age, which was 65 yr for men with a family history and proximal cancer compared to 70 yr for their counterparts without the family history (p = 0.03). The anatomic location of the cancer, presence of distal benign neoplasia when the cancer was proximal, and disease stage at diagnosis were not different between the groups.

CONCLUSIONS

Men with a family history of sporadic colorectal cancer and proximal colon cancer were younger than men without the family history and proximal colon cancer. The overall results do not indicate that a change in the diagnostic approach is needed.

Incomplete screening flexible sigmoidoscopy associated with female sex, age, and increased risk of colorectal cancer

BACKGROUND

Several previous studies have found that females and older individuals are at greater risk of having incomplete flexible sigmoidoscopy. However, no prior study has reported the subsequent risk of colorectal cancer (CRC) following incomplete sigmoidoscopy.

METHODS

Using data from 55 791 individuals screened as part of the Colon Cancer Prevention (CoCaP) programme of Kaiser Permanente of Northern California, we evaluated the likelihood of having an inadequate (<40 cm) examination by age and sex, and estimated the risk of distal CRC according to depth of sigmoidoscope insertion at the baseline screening examination. Multivariate estimation of risks was performed using Poisson regression.

RESULTS

Older individuals were at a much greater risk of having an inadequate examination (relative risk (RR) for age 80+ years compared with 50-59 years 2.6 (95% confidence interval (CI) 2.3-3.0)), as were females (RR 2.3 (95% CI 2.2-2.5)); these associations were attenuated but remained strong if Poisson models were further adjusted for examination limitations (pain, stool, and angulation). There was an approximate threefold increase in the risk of distal CRC if the baseline sigmoidoscopy did not reach a depth of at least 40 cm; a smaller increase in risk was observed for examinations that reached 40-59 cm.

CONCLUSIONS

Older individuals and women are at an increased risk of having inadequate sigmoidoscopy. Because inadequate sigmoidoscopy results in an increased risk of subsequent CRC, physicians should consider steps to maximise the depth of insertion of the sigmoidoscope or, failing this, should consider an alternative screening test.

Applying a stage model of behavior change to colon cancer screening

BACKGROUND

There has been limited use of stages of change models in characterizing colorectal cancer (CRC) screening. We assess the applicability of the Precaution Adoption Model (PAPM) by determining the distribution of stages of adoption and by elucidating differences among stages.

METHODS

The study is based on 1394 responses (69%) to a survey mailed in 2002 to patients in a primary care population. Survey measures included: self-reported CRC screening, sociodemographic characteristics, health system characteristics, attitudes and beliefs about CRC screening, perceived vulnerability to CRC, and worry about CRC. The main outcome was PAPM stage of adoption of CRC screening based on the ACS preferred guidelines: colonoscopy every 10 years alone or the combination annual FOBT plus sigmoidoscopy every 5 years.

RESULTS

57% were up-to-date with at least one test; 36% were up-to-date with the ACS preferred guidelines; provider recommendation, positive family history of CRC, and positive decisional balance score were significantly associated with higher compared to lower PAPM stages.

CONCLUSIONS

The combination of PAPM stage assignment and other factors provides useful information for designing tailored interventions. There are special challenges in developing and interpreting PAPM stage assignments when a guideline offers multiple pathways to adherence and recommends a combination of two tests as a preferred option.

Changing patterns of colorectal cancer in China over a period of 20 years

AIM: To determine whether any changes have occurred on the patterns of colorectal cancer in China.

METHODS: Data from 21 Chinese articles published from 1980 to 1999, were used to analyze the time trend of colorectal cancer according to the patients’ age at diagnosis, sex, the site of the tumor, stage, and the pathology.

RESULTS: From 1980s to 1990s, the mean age of the colorectal cancer patients has increased. The percentage of the female patients rose. The distribution of colorectal carcinoma shows a predominance of rectal cancer. However, the proportion of proximal colon cancer (including transverse and ascending colon) increased significantly accompanied by a decline in the percentage of rectal cancer. Similarity in the percentage of distal colon cancer between two decades was revealed. In the 1990s, statistically more Stage B patients were found than those in 1980s. In addition, databases show a significant decrease in the Stage D cases. The proportion of adenocarcinoma increased, but the mucinous adenocarcinoma decreased during two decades.

CONCLUSION: These findings indicate that the pattern of colorectal cancer in China has been changing. Especially, a proximal shift due to the increasing proportion of ascending and transverse colon cancer has occurred in China.

Colorectal cancer screening in HIV-infected patients 50 years of age and older: missed opportunities for prevention

OBJECTIVES

Although human immunodeficiency virus (HIV)-infected patients are now living longer, there are no published data on colorectal cancer (CRC) screening in this population. We hypothesized that HIV-infected patients were less likely to be screened for CRC compared to patients without HIV.

METHODS

Consecutive HIV-infected patients > or =50 yr old seen in our outpatient clinic from 1/1/01 to 6/30/02 were identified. For each HIV-infected patient, we selected one age- and gender-matched control subject without HIV infection who was seen during the same time period. The electronic medical records were reviewed to determine the proportion of patients that had a fecal occult blood test (FOBT), flexible sigmoidoscopy, air-contrast barium enema (ACBE), or colonoscopy.

RESULTS

During the 18-month study period, 538 HIV-infected outpatients were seen and 302 (56.1%) were > or =50 yr old. Despite significantly more visits with their primary care provider, HIV-infected patients were less likely to have ever had at least one CRC screening test (55.6%vs 77.8%, p < 0.001). The proportion of HIV-infected patients who ever had a FOBT (43.0%vs 66.6%, p < 0.001), flexible sigmoidoscopy (5.3%vs 17.5%, p < 0.001), ACBE (2.6%vs 7.9%, p= 0.004), or colonoscopy (17.2%vs 27.5%, p= 0.002) was significantly lower than in control subjects. In addition, HIV-infected patients were significantly less likely to be up-to-date with at least one CRC screening test according to current guidelines (49.3%vs 65.6%, p < 0.001).

CONCLUSIONS

A substantial number of HIV-infected patients are > or =50 yr of age and CRC screening is underutilized in this population. Public health strategies to improve CRC screening in HIV-infected patients are needed.

Predictors of fecal occult blood test (FOBT) completion among low-income adults

BACKGROUND

Fecal occult blood testing (FOBT) can reduce colorectal cancer (CRC) mortality. Unfortunately, CRC screening is underutilized. Sociocultural mediators of FOBT adherence have not been extensively studied in lower income, minority populations. This study prospectively studied FOBT return in a low-income, multiethnic population.

METHODS

Participants (N = 298), aged > or =40 years, were surveyed and given FOBT kits with instructions. Those not returning kits within 30 days received a reminder telephone call. Bivariate and multivariate analyses assessed predictors of FOBT card return at 90 days.

RESULTS

Participants (median age = 48) were predominately African American (69%), without private insurance (88%), and of low income. The largest group of participants preferred FOBT alone (46%), followed by whatever my doctor recommends (19%), endoscopy + annual FOBT (16%), endoscopy alone (14%), and no screening (5%). In multivariate analyses, FOBT return was predicted by age (OR = 1.05) and lack of reported FOBT barriers (OR = 3.81). Among those > or =50 and not up-to-date with screening, FOBT return was predicted by cancer fatalism (OR = 0.83). FOBT barriers were associated with age (OR = 0.96), less than high school education (OR = 2.05), and less physician trust (OR = 2.12). Endoscopy barriers were associated with age (OR = 0.93), less physician trust (OR = 1.95), and female gender (OR = 3.45).

CONCLUSIONS

Younger individuals and those with less education, less trust in health care providers, and more fatalistic beliefs are at risk for CRC screening non-adherence. Strategies addressing common misconceptions should improve CRC screening rates in low-income, multiethnic populations.

Screening and surveillance of colorectal cancer

Although colorectal cancer (CRC) is the second leading cause of cancer deaths in the United States, it is preventable. Screening modalities include fecal occult blood testing, flexible sigmoidoscopy, double-contrast barium enema, and colonoscopy. Colonoscopy allows effective detection and removal of precursor adenomatous polyps and is the dominant CRC screening modality. Emerging technologies include CT and MR colonography and fecal DNA tests. Effective and cost-effective surveillance after polypectomy and curative CRC resection requires balancing the protective effect of polypectomy while maximizing intervals between examinations; thus, estimation of the risk of recurrence determines the intensity of surveillance for individual patients.

Market for colorectal cancer screening by endoscopy in the United States

In the United States, colorectal cancer (CRC) ranks third among all cancer sites in incidence, and second in cancer-related mortality. Although screening reduces CRC incidence and mortality, current screening rates among the average-risk population are low. The traditional way of promoting CRC screening has been to educate healthcare providers and the public on its benefits, available screening procedures, and current guidelines. In this paper, we focus on economics and provide an overview of some key factors that affect the demand for and the supply of CRC screening by endoscopy. Factors affecting the demand for endoscopic CRC screening include the number of people for whom screening is recommended, consumers' income and health insurance status, time and travel costs, prices of non-endoscopic CRC screening tests, and personal preferences and perceived quality of care. Factors influencing the supply of endoscopic screening include the availability of endoscopic providers, increased efficiency, procedure costs, current reimbursement rates for endoscopic procedures, and technical progress. The volume of screening tests in the market is determined jointly by the collective demand and supply decisions of consumers and providers. The discussion includes policy implications for the current effort to promote widespread use of CRC screening in the United States.

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.

Use of a patient navigator to increase colorectal cancer screening in an urban neighborhood health clinic

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States. Racial disparities in CRC incidence and mortality have been well documented. In addition, lower rates of CRC screening among ethnic minorities have been reported. Therefore, we tested the effectiveness of a patient navigator (PN) in increasing compliance with CRC screening in a minority community health setting. Men and women aged 50 or older attending a primary care practice were enrolled if they had not had a fecal occult blood test within the past year, a sigmoidoscopy or barium enema within the past 3-5 years, or a colonoscopy within the past 10 years. Participants were randomly assigned either to receive navigator services (PN+) or not to receive navigator services (PN-). There were no demographic differences between the two groups. Within 6 months of physician recommendation, 15.8% in the PN+group had complied with an endoscopic examination, compared with only 5% in the PN - group (P=.019). The PN+group also demonstrated higher rates of fecal occult blood test completion (42.1% vs. 25%, P=.086). Thus, a PN system successfully increases CRC screening rates among a predominantly minority population of low socioeconomic status.

Reduction of clinically manifest colorectal cancer by endoscopic screening: empirical evaluation and comparison of screening at various ages

Endoscopic screening (sigmoidoscopy, colonoscopy) with removal of precancerous lesions can prevent a large proportion of colorectal cancers (CRCs). However, there is lack of data regarding optimal age, time intervals and numbers of screening examinations. We developed and applied modified techniques of epidemiological analysis to evaluate the impact of various endoscopy-based screening strategies on prevention of clinically manifest CRCs between the ages of 50 and 79 in a population-based case-control study (294 cases, 254 controls) conducted in Saarland, Germany. We found a strong potential for reduction of CRC occurrence even with a single screening endoscopy. The optimal age for a single screening endoscopy appears to be around 55 (estimated potential for prevention of cases between the ages of 55 and 79 in case of 100% compliance: 77% (95% confidence interval (CI) 46-90%)). A single screening endoscopy at age 50 would have a lower impact due to failure to prevent CRC at higher ages. Similarly, screening at ages 60 or older would have a lower impact because it would fail to prevent CRC at lower ages. Repeated offers of screening examinations could provide substantial additional benefit with the levels of compliance to be expected in practice, but they would have to be weighed against the increased risks and costs.

The impact of physicians' health beliefs on colorectal cancer screening practices

Primary-care physicians have significant influence on whether or not their patients participate in colorectal cancer screening (CRCS). This study explored the association of physicians' personal health beliefs, medical history, and personal participation in CRCS with their practice patterns regarding CRCS. Perceived personal risk for colorectal cancer (CRC) was associated with compliance with American Cancer Society (ACS) guidelines for CRCS for their patients (P = 0.03). For physicians at low risk for CRC, their perception of the seriousness of CRC was significantly associated with compliance (P = 0.047). For physicians at, at least, average risk for CRC, personal participation in CRCS did not predict whether they recommend CRCS to their patients. Efforts to improve physicians' understanding about their own susceptibility to CRC and the seriousness of CRC may improve their compliance with making recommendations for CRCS to their patients and may improve their participation in CRCS.