Fecal occult blood and flexible sigmoidoscopy screening for colorectal cancer: modeling the impact on colonoscopy requirements and cancer detection rates

AiM: The aim of this study was to estimate the colonoscopy requirements and the likely impact of fecal occult blood and flexible sigmoidoscopy screening on the detection of colorectal cancer by using previously published data. METHODS: Fecal occult blood and flexible sigmoidoscopy screening programs were applied to the 2.04 million subjects aged 50-65 years, at a participation rate of 40%. The following strategies were evaluated: Fecal occult blood testing with colonoscopy follow up of all positive tests; flexible sigmoidoscopy with colonoscopy follow up of all adenomatous polyps; and flexible sigmoidoscopy with colonoscopy follow up of all adenomatous polyps > 10 mm in size. RESULTS: The fecal occult blood program detected 5.6% of all colorectal cancer cases at a rate of 2,914 colonoscopies/percentage of detection of colorectal cancer. The flexible sigmoidoscopy program detected 14% of all colorectal cancer cases at a rate of 8,160 colonoscopies/percentage of detection of colorectal cancer. The flexible sigmoidoscopy program with follow up of adenomatous polyps > 10 mm in size detected 13% of all colorectal cancer cases at a rate of 1,230 colonoscopies/percentage of detection of colorectal cancer. CONCLUSIONS: Flexible sigmoidoscopy screening followed by colonoscopic follow up of adenomatous polyps > 10 mm in size is the most efficient screening strategy in terms of colonoscopies generated and cases of colorectal cancer detected.     

Cost-effectiveness of colorectal cancer screening: comparison of community-based flexible sigmoidoscopy with fecal occult blood testing and colonoscopy

BACKGROUND AND AIMS: To determine the cost-effectiveness of screening for colorectal cancer using flexible sigmoidoscopy once every 10 years, compared with annual and biennial rehydrated Hemoccult fecal occult blood testing and colonoscopy once every 10 years, or no screening. METHODS: A Markov model was developed in order to simulate the progression of a cohort of asymptomatic, average-risk individuals aged 55-64 years who were moving through a defined series of states towards death. The main outcome measures were: cases of colorectal cancer averted, colorectal cancer deaths averted, and cost per life-year saved. RESULTS: Colonoscopy averted the greatest number of cases of colorectal cancer (35%), followed by flexible sigmoidoscopy (25%), and annual (24%) and biennial (14%) fecal occult blood testing. Colonoscopy averted the greatest number of deaths from colorectal cancer (31%), followed by annual fecal occult blood testing (29%), flexible sigmoidoscopy (21%) and biennial fecal occult blood testing (19%). Flexible sigmoidoscopy was the most efficient in terms of cost per life-year saved (16,801 Australian dollars), followed by colonoscopy (19,285 Australian dollars), biennial (41,183 Australian dollars), and annual (46,900 Australian dollars) fecal occult blood testing. CONCLUSIONS: Flexible sigmoidoscopy and colonoscopy are cost-effective strategies for reducing the disease burden of colorectal cancer.     

Cost-effectiveness of colonoscopy in screening for colorectal cancer

BACKGROUND: Fecal occult blood testing, flexible sigmoidoscopy, and colonoscopy are used to screen patients for colorectal cancer. OBJECTIVE: To compare the cost-effectiveness of fecal occult blood testing, flexible sigmoidoscopy, and colonoscopy. DESIGN: The cost-effectiveness of the three screening strategies was compared by using computer models of a Markov process. In the model, a hypothetical population of 100 000 persons 50 years of age undergoes annual fecal occult blood testing, sigmoidoscopy every 5 years, or colonoscopy every 10 years. Positive results on fecal occult blood testing or adenomatous polyps found during sigmoidoscopy are worked up by using colonoscopy. After polypectomy, colonoscopy is repeated every 3 years until no polyps are found. DATA SOURCES: Transition rates were estimated from U.S. vital statistics and cancer statistics and from published data on the sensitivity, specificity, and efficacy of various screening techniques. Costs of screening and cancer care were estimated from Medicare reimbursement data. TARGET POPULATION: Persons 50 years of age in the general population. TIME HORIZON: The study population was followed annually until death. PERSPECTIVE: Third-party payer. OUTCOME MEASURE: Incremental cost-effectiveness ratio. RESULTS OF BASE-CASE ANALYSIS: Compared with colonoscopy, annual screening with fecal occult blood testing costs less but saves fewer life-years. A screening strategy based on flexible sigmoidoscopy every 5 or 10 years is less cost-effective than the other two screening methods. RESULTS OF SENSITIVITY ANALYSIS: Screening with fecal occult blood testing is more sensitive to changes in compliance rates, and it becomes easily dominated by colonoscopy under most conditions assuming less than perfect compliance. Other assumptions about the sensitivity and specificity of fecal occult blood testing, screening frequency, efficacy of colonoscopy in preventing cancer, and polyp incidence have a lesser influence on the differences in cost-effectiveness between colonoscopy and fecal occult blood testing. CONCLUSIONS: Colonoscopy represents a cost-effective means of screening for colorectal cancer because it reduces mortality at relatively low incremental costs. Low compliance rates render colonoscopy every 10 years the most cost-effective primary screening strategy for colorectal cancer.     

Which colon cancer screening test? A comparison of costs, effectiveness, and compliance.

PURPOSE: Recent media reports have advocated the use of colonoscopy for colorectal cancer screening. However, colonoscopy is expensive compared with other screening modalities, such as fecal occult blood testing and flexible sigmoidoscopy. We sought to determine the cost effectiveness of different screening strategies for colorectal cancer at levels of compliance likely to be achieved in clinical practice. METHODS: A Markov decision model was used to examine screening strategies, including fecal occult blood testing alone, fecal occult blood testing combined with flexible sigmoidoscopy, flexible sigmoidoscopy alone, and colonoscopy. The timing and frequency of screening was varied to assess optimal screening intervals. Sensitivity analyses were conducted to assess the factors that have the greatest effect on the cost effectiveness of screening. RESULTS: All strategies are cost effective versus no screening, at less than $20,000 per life-year saved. Direct comparison suggests that the most effective strategies are twice-lifetime colonoscopy and flexible sigmoidoscopy combined with fecal occult blood testing. Assuming perfect compliance, flexible sigmoidoscopy combined with fecal occult blood testing is slightly more effective than twice-lifetime colonoscopy (at ages 50 and 60 years) but is substantially more expensive, with an incremental cost effectiveness of $390,000 per additional life-year saved. However, compliance with primary screening tests and colonoscopic follow-up for polyps affect screening decisions. Colonoscopy at ages 50 and 60 years is the preferred test regardless of compliance with the primary screening test. However, if follow-up colonoscopy for polyps is less than 75%, then even once-lifetime colonoscopy is preferred over most combinations of flexible sigmoidoscopy and fecal occult blood testing. Costs of colonoscopy and proportion of cancer arising from polyps also affect cost effectiveness. CONCLUSIONS: Colonoscopic screening for colorectal cancer appears preferable to current screening recommendations. Screening recommendations should be tailored to the compliance levels achievable in different practice settings.     

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.     

Is there endoscopic capacity to provide colorectal cancer screening to the unscreened population in the United States?

BACKGROUND & AIMS: Screening rates for colorectal cancer remain low compared with screening rates for other cancers. The size of the unscreened population and the capacity to provide widespread screening are unknown. We estimated the number of average-risk persons aged 50 years or older not screened for colorectal cancer, the number of procedures required for this population, and the endoscopic capacity to satisfy this unmet need. METHODS: Using data from the US Census Bureau and the Centers for Disease Control and Prevention's National Health Interview Survey, we designed a forecasting model to estimate the number of persons in the United States currently not screened for colorectal cancer and the number of examinations needed to screen these persons. Test need was compared with available capacity, based on results from the national Survey of Endoscopic Capacity, assuming different proportions of available capacity were used for colorectal cancer screening. RESULTS: Approximately 41.8 million average-risk people aged 50 years or older have not been screened for colorectal cancer according to national guidelines. Sufficient capacity exists to screen the unscreened population within 1 year using fecal occult blood testing followed by diagnostic colonoscopy for positive tests. Depending on the proportion of available capacity used for colorectal cancer screening, it could take up to 10 years to screen the unscreened population using flexible sigmoidoscopy or colonoscopy. CONCLUSIONS: The capacity exists for widespread screening with fecal occult blood testing. The capacity for screening with flexible sigmoidoscopy or colonoscopy depends on the proportion of available capacity used for colorectal cancer screening.     

Racial and ethnic colorectal cancer patterns affect the cost-effectiveness of colorectal cancer screening in the United States

BACKGROUND & AIMS: Colorectal cancer screening beginning at age 50 is recommended for all Americans considered at "average" risk for the development of colorectal cancer. METHODS: We used 1988-1995 California Cancer Registry data to compare the cost-effectiveness of two 35-year colorectal cancer screening interventions among Asians, blacks, Latinos, and Whites. RESULTS: Average annual age-specific colorectal cancer incidence rates were highest in blacks and lowest in Latinos. Screening beginning at age 50 was most cost-effective in blacks and least cost-effective in Latinos (measured as dollars spent per year of life saved), using annual fecal occult blood testing (FOBT) combined with flexible sigmoidoscopy every 5 years and using colonoscopy every 10 years. A 35-year screening program beginning in blacks at age 42, whites at age 44, or Asians at age 46 was more cost-effective than screening Latinos beginning at age 50. CONCLUSIONS: Colorectal cancer screening programs beginning at age 50, using either FOBT and flexible sigmoidoscopy or colonoscopy in each racial or ethnic group, are within the $40,000-$60,000 per year of life saved upper cost limit considered acceptable for preventive strategies. Screening is most cost-effective in blacks because of high age-specific colorectal cancer incidence rates.     

Colorectal cancer screening in Italy: feasibility and cost-effectiveness in a model area.

OBJECTIVE: To evaluate the feasibility and cost-effectiveness of screening programmes for colorectal cancer in Italy. DESIGN; We compared five types of programmes: annual faecal occult blood testing, sigmoidoscopy (every 5 years), faecal occult blood testing plus sigmoidoscopy (every 1 and 5 years), colonoscopy (every 10 years) (all in the age group 55-69 years, last examination at 70 years) and 'filter' colonoscopy. The latter had to be performed in persons at 50 years of age and repeated every 10 years until the age of 70. Costs for the tests and colon cancer care were paid by the Regional Health Office to the hospitals performing the procedures/treatments. SETTING: Data were applied to a small model area in northern Italy (Gemona, 80,000 inhabitants) with well-known demographic (age distribution) and epidemiological (colon cancer incidence) features. RESULTS: All-inclusive 10-year costs per screenee and per death prevented (in US dollars) were: 965 and 77,200 for faecal occult blood testing; 436 and 15,500 for sigmoidoscopy; 1521 and 35,000 for sigmoidoscopy plus faecal occult blood testing; 510 and 15,100 for colonoscopy; 510 and 14,000 for 'filter' colonoscopy. With 'filter' colonoscopy the programme required 870 colonoscopies per year, while with colonoscopy 13,700 colonoscopies were needed at time zero. CONCLUSIONS: In Italy, screening programmes based on sigmoidoscopy/colonoscopy are more cost effective than those based on faecal occult blood testing. 'Filter' colonoscopy at age 50 appears superior to the other types of endoscopy-based screening programmes because it utilizes, at any point in time, a much smaller fraction of available resources.     

Survey of internal medicine residents' use of the fecal occult blood test and their understanding of colorectal cancer screening and surveillance

OBJECTIVE: Primary care physicians have imperfect understanding of current colorectal cancer screening guidelines and recommendations. Furthermore, compliance with colorectal cancer screening by internal medicine residents has been demonstrated to be poor. We sought to identify whether current trainees in internal medicine had adequate understanding of colorectal cancer screening and surveillance and test utilization. METHODS: We applied a structured questionnaire about colorectal cancer screening and the use of fecal occult blood tests to 168 internal medicine residents at four accredited programs in the U.S. They were also asked for recommendations about six hypothetical patients who may have been candidates for screening or surveillance. RESULTS: Seventy-one percent identified 50 yr as the currently recommended age to commence screening in an average-risk individual; 64.3% would begin screening with fecal occult blood testing and flexible sigmoidoscopy and 4.8% with colonoscopy. Most perform fecal occult blood testing on stool obtained at digital rectal exam and without prior dietary restrictions. Many use fecal occult blood testing for indications other than colorectal cancer screening. Only 29% recommended colonoscopy to evaluate a positive fecal occult blood test. Most residents plan to be screened for colorectal neoplasia at the appropriate age; significantly more opted for colonoscopy than recommended it for their patients. CONCLUSIONS: Internal medicine residents have many misperceptions regarding colorectal cancer screening and the utility of the fecal occult blood test. Educational efforts should be directed at internal medicine residents, many of whom plan careers in primary care, where most colorectal cancer screening is currently performed.     

Cost-Effectiveness of Colon Cancer Screening

The cost-effectiveness of two colon cancer-screening strategies was compared. The first strategy mirrors the recommendations of the American Cancer Society and includes sigmoidoscopy starting at age 50, and yearly fecal occult blood testing. The second strategy is screening with colonoscopy. The analysis revealed that the 10-yr cost of screening with sigmoidoscopy is nearly $1,700, compared with nearly $2,500 for colonoscopy, using prevailing procedure costs. This difference can be reduced by lowering the cost of normal colonoscopies. The cost of identifying one patient with an adenomatous polyp is $8,766 with sigmoidoscopy, compared to $5,988 with colonoscopy because of the higher detection rate with colonoscopy. The calculated cost of preventing one death from colon cancer is $444,133 with sigmoidoscopy versus $347,214 with colonoscopy. In conclusion, colon cancer prevention with current screening methods is very costly. Screening with sigmoidoscopy and fecal occult blood testing may not be cost-effective, compared to screening with colonoscopy.     

Cost effectiveness of colorectal cancer screening in the elderly

OBJECTIVE: To assess the cost effectiveness of a periodic program of colorectal cancer screening in the elderly. DESIGN: A model was constructed of four strategies for the periodic screening of persons 65 to 85 years of age. The effect of each strategy on life expectancy and health care costs was estimated under assumptions that were uniformly unfavorable to screening. Cost and added years of life were discounted at 5% per year. Cost per year of life gained from screening was calculated for each screening strategy. DATA SOURCES: Assumptions used in the model were based on a review of pertinent studies; those studies with results more unfavorable to screening were given more weight. Strengths and weaknesses of studies are discussed. MAIN RESULTS: A program of annual fecal occult blood testing (FOBT) in the elderly would detect at least 17% of the expected cases of cancer and could cost $35,000 per year of life saved. Screening schedules that include periodic sigmoidoscopy would prevent more cases of cancer but could cost between $43,000 and $47,000 per year of life gained. These estimates are based on uncertain assumptions, but results were not extremely sensitive to further relaxation of the values of the most uncertain assumptions. In no case did the cost per year of life gained from annual FOBT exceed $55,000 or did the cost per year of life gained from FOBT with sigmoidoscopy every 5 years exceed $61,000. CONCLUSIONS: Although colorectal cancer screening is costly in the aggregate, its potential medical benefits make it a reasonably cost-effective preventive intervention for the elderly.     

Flexible sigmoidoscopy for colorectal cancer screening: valid approach or short-sighted?

Flexible sigmoidoscopy is a safe, effective test that may be delivered feasibly on a large scale for mass colorectal cancer screening. Flexible sigmoidoscopy is 67% to 80% as sensitive as colonoscopy in a screening population, but is probably 10 to 20 times safer than colonoscopy in terms of complications. Several national guidelines recommend combining flexible sigmoidoscopy with fecal occult blood tests. There is limited evidence to support this practice, and the added benefit to an existing flexible sigmoidoscopy screening program although real, may be marginal. In the future, it is likely that flexible sigmoidoscopy screening among patients aged 50 to 65 will be supplemented with total colonic screening, using molecular-based fecal tests or virtual colonoscopy, after age 65.     

Screening des kolorektalen Karzinoms

Colorectal cancer is common and suitable for screening. There is general agreement that screening for colorectal cancer in the asymptomatic population without familial risk should begin at age 50. The different screening methods can be separated into methods that mainly detect cancers (fecal occult blood tests, genetic stool tests, blood tests, and the M2-PK test) and methods that diagnose cancers and polyps (colonoscopy, sigmoidoscopy, CT/MRI colonography, and colon capsule endoscopy). Endoscopic methods enable detection and treatment of preneoplastic adenomas and, thus, make cancer prevention possible. In the current German S3 guideline, colonoscopy is recommended as the preferred screening test. For people unwilling to undergo endoscopic screening, the fecal occult blood test is an alternative. Colonoscopy has been part of the German Cancer Screening Program since 2002.     

Flexible sigmoidoscopy as a screening test for colorectal cancer

Flexible sigmoidoscopy (FS) is one of the screening modalities for colorectal cancer. The rationale for screening with flexible sigmoidoscopy is that it provides direct visualisation of the colon, and suspicious lesions can be biopsied. The most obvious disadvantage is that it examines only the lower third of the colon. The technical aspects of FS are sufficiently clear to enable us to define what FS can and cannot do. From the point of view of screening, FS clearly cannot completely exclude the presence of colon cancer in all asymptomatic people. A distinction must be made between screening the general population and testing the individual seeking screening. For the former, obtaining the greatest mortality benefit safely and at an acceptable cost to the nation is the crux of the matter. Recently published data indicate that FS is a cost-effective screening strategy, although colonoscopy and annual fecal occult blood test avert a greater number of cancer deaths. The results of randomised controlled trials of screening FS and colonoscopy, currently being conducted, will allow us to make a more accurate comparison with the established data regarding fecal occult blood test. In conclusion, flexible sigmoidoscopy every 5 years with or without FOBT is one of the screening methods recommended by major professional organizations. It identifies 50 to 70% of the advanced neoplasms, if any discovery of a distal neoplasia is followed up with a total examination of the colon by colonoscopy.     

Resource implications for a population-based colorectal cancer screening program in Canada: a study of the impact on colonoscopy capacity and costs in London, Ontario.

OBJECTIVE: Cancer Care Ontario has recommended a population-based colorectal cancer (CRC) screening program using fecal occult blood testing. Patients who test positive should undergo further investigation, preferably colonoscopy. So far, no studies have been performed to quantify the costs or demands on the health care system at the community level. The number of consultations, colonoscopies and polypectomies, and the corresponding direct medical costs generated by the CRC screening program, between 2006 and 2015 in London, Ontario, were estimated using a decision analysis model in comparison with the population health model. METHODS: A faxed survey study was conducted to examine the current CRC screening practice among family physicians in London. Data from the survey and randomized studies were applied to a decision analysis model, which simulated the steps involved in population-based biennial and annual CRC screening between 2006 and 2015. The number of consultations, colonoscopies and polypectomies, and their associated costs were calculated. RESULTS: For a cohort population of 140,000, between 50 and 74 years of age, in 2006 to 2015, it is estimated that an average of 412 consultations, 463 colonoscopies and 174 polypectomies will be performed per 100,000 screen eligible population per year in biennial screening, and double in annual screening, reflecting an average of 8.7% or 17.6% increase annually in outpatient colonoscopies, respectively, compared with 2003. A mean of $285,000 or $562,000 per year would be required to support the extra consultation and endoscopic procedures generated by the biennial or annual screening. CONCLUSION: Population-based fecal occult blood testing screening for CRC appears to be a manageable strategy if a modest increase in endoscopic resources is allocated.     

What is the most cost-effective strategy to screen for second primary colorectal cancers in male cancer survivors in Korea？

AIM： To identify a cost-effective strategy of second primary colorectal cancer （CRC） screening for cancer survivors in Korea using a decision-analytic model. METHODS： A Markov model estimated the clinical and economic consequences of a simulated 50-year- old male cancer survivors＇ cohort, and we compared the results of eight screening strategies： no screening, fecal occult blood test （FOBT） annually, FOBT every 2 years, sigmoidoscopy every 5 years, double contrast barium enema every 5 years, and colonoscopy every 10 years （COL10）, every 5 years （COL5）, and every 3 years （COL3）. We included only direct medical costs, and our main outcome measures were discounted lifetime costs, life expectancy, and incremental cost- effectiveness ratio （ICER）. RESULTS： In the base-case analysis, the non-dominat- ed strategies in cancer survivors were COL5, and COL3. The ICER for COL3 in cancer survivors was $5593/life- year saved （LYS）, and did not exceed $10000/LYS in one-way sensitivity analyses. If the risk of CRC in can- cer survivors is at least two times higher than that in the general population, COL5 had an ICER of less than $10500/LYS among both good and poor prognosis of index cancer. If the age of cancer survivors starting CRC screening was decreased to 40 years, the ICER of COL5 was tess than $7400/LYS regardless of screening compliance. CONCLUSION： Our study suggests that more strict and frequent recommendations for colonoscopy such as COL5 and COL3 could be considered as economically reasonable second primary CRC screening strategies for Korean male cancer survivors.     

Many participants in fecal occult blood test population screening have a higher-than-average risk for colorectal cancer

OBJECTIVES: Population-based colorectal cancer screening by fecal occult blood testing reduces cancer-specific mortality. Current guidelines recommend this strategy for average risk individuals. This study investigated the prevalence of higher-than-average risk characteristics, and rate of prior colonoscopy, in participants in fecal occult blood test screening programs. METHODS: Randomly selected individuals aged 50-74 years in urban Adelaide were offered free fecal occult blood test screening by mail, without prior knowledge of their medical status. Each invitation included a questionnaire to record the prevalence of higher-than-average risk characteristics related to symptoms, family history or comorbidity, as well as prior colonoscopy. The definition of average risk was taken from updated guidelines published by the US Multisociety Task Force on Colorectal Cancer. RESULTS: Of 2538 responses analyzed, 425 individuals had had a colonoscopy within the last 5 years, 106 fulfilled family history criteria for an initial screening colonoscopy, 209 had past polyps and 26 had had colorectal cancer. Eighty-three reported recent rectal bleeding. By current guidelines, 23% of the screened population did not warrant fecal occult blood test, because either prior colonoscopy rendered it unnecessary or particular patient characteristics made colonoscopy a more appropriate initial investigation. CONCLUSIONS: Fecal occult blood test screening programs capture a sizeable number of higher-than-average risk individuals that may warrant colonoscopic rather than fecal occult blood test screening. Other participants have had a recent colonoscopy and probably warrant a delay in screening. Mass population fecal occult blood test-based screening programs need to more effectively target those at average risk and should divert those of higher or lower risk to more individualized assessment.     

The use of screening colonoscopy for patients cared for by the Department of Veterans Affairs

BACKGROUND: Medicare data indicate an increase in colorectal cancer (CRC) screening using colonoscopy and a decline in fecal occult blood testing, flexible sigmoidoscopy, and double-contrast barium enema. Because of differences in the delivery of health care, this trend in use of colonoscopy in fee-for-service settings might not be paralleled in the Department of Veterans Affairs (VA). METHODS: National inpatient and outpatient VA databases were searched for codes indicative of colonoscopy, flexible sigmoidoscopy, fecal occult blood testing, and double-contrast barium enema during fiscal years 1998 to 2003 among VA users aged 49 to 75 years. RESULTS: The frequency of tests for CRC screening increased from 432,778 in 1998 to 1,179,764 in 2003. Of those who were screened, only the proportion of subjects screened with fecal occult blood testing increased from 81.7% to 90.4%, while screening colonoscopy declined from 5.7% to 4.7%; flexible sigmoidoscopy declined from 8.3% to 3.6%; and double-contrast barium enema declined from 4.1% to 1.3%. The total use of screening colonoscopy procedures increased from 24,955 in 1998 to 55,199 in 2003, but the proportion of colonoscopy procedures performed for CRC screening purposes increased only slightly from 34.3% to 38.4%. In regression models adjusting for age, race, and sex, there was no consistent secular trend in the likelihood of undergoing screening colonoscopy for patients cared for in the VA health care system. CONCLUSIONS: Colorectal cancer screening has dramatically increased in the VA, but unlike in other practice settings, fecal occult blood testing is the dominant mode of screening. Although screening colonoscopy more than doubled in frequency, it constitutes a small proportion of the total CRC screening procedures used in the VA health care setting.     

Survey of the opinions, knowledge, and practices of gastroenterologists regarding colorectal cancer screening and use of the fecal occult blood test

OBJECTIVES: Primary care physicians and internal medicine residents have poor understanding of colorectal cancer screening and the use of fecal occult blood tests. If acceptance and implementation of colorectal cancer screening is to improve, gastroenterologists may have to take a more leading role in the education of their primary care colleagues, physicians in training, and the general public. However, before this can be recommended, it is necessary to determine how closely gastroenterologists follow currently recommended guidelines and how they use fecal occult blood tests. METHODS: We mailed a two-page, structured questionnaire about colorectal cancer screening and use of fecal occult blood tests to 8000 randomly selected gastroenterologists in the United States. RESULTS: We received responses from 24% of the gastroenterologists. Almost all used fecal occult blood tests in the office setting, 86% on stool obtained at rectal examination. The test was frequently used for reasons other than colorectal cancer screening, and often without adequate patient instruction on dietary and medication restrictions. Of the respondents, 98% commenced screening at age < or = 50 yr, whereas 37% either continued screening into advanced age or never stopped. Annual fecal occult blood testing with flexible sigmoidoscopy every 5 yr was the screening strategy recommended by 71% of the respondents, whereas 25% recommended colonoscopy every 10 yr. However, 77% of the gastroenterologists chose colonoscopy for personal colorectal cancer screening. CONCLUSIONS: Gastroenterologists usually give appropriate advice on colorectal cancer screening but often misuse fecal occult blood tests. This may produce excessively high false-positive screening rates, leading to unnecessary diagnostic testing without apparent benefit.     

Screening for colorectal cancer on the front line

OBJECTIVE: The aim of this study was to assess knowledge, beliefs, and practices of primary care clinicians regarding colorectal cancer screening. METHODS: We surveyed 77 primary care providers in six clinics in central Massachusetts to evaluate several factors related to colorectal cancer screening. RESULTS: Most agreed with guidelines for fecal occult blood test (97%) and sigmoidoscopy (87%), which were reported commonly as usual practice. Although the majority (86%) recommended colonoscopy as a colorectal cancer screening test, it was infrequently reported as usual practice. Also, 36% considered barium enema a colorectal cancer screening option, and it was rarely reported as usual practice. Despite lack of evidence supporting effectiveness, digital rectal examinations and in-office fecal occult blood test were commonly reported as usual practice. However, these were usually reported in combination with a guideline-endorsed testing option. Although only 10% reported that fecal occult blood test/home was frequently refused, 60% reported sigmoidoscopy was. Frequently cited patient barriers to sigmoidoscopy compliance included fear the procedure would hurt and that patients assume symptoms occur if there is a problem. Perceptions of health systems barriers to sigmoidoscopy were less strong. CONCLUSIONS: Most providers recommended guideline-endorsed colorectal cancer screening. However, patient refusal for sigmoidoscopy was common. Results indicate that multiple levels of intervention, including patient and provider education and systems strategies, may help increase prevalence.