Asymptomatic Average-risk Patients Research Articles

Knowledge, Attitude, and Practice of Colorectal Cancer Screening Among Primary Healthcare Physicians in Riyadh Second Health Cluster.

Colorectal cancer is the third common cancer, and the second common cause of cancer death in the world. According to the 2014 Cancer Incidence Report of the Kingdom of Saudi Arabia, colorectal cancer account for 11.5% from all cancers reported among Saudi nationals. By the year 2030, the incidence of colorectal cancer could increase fourfold among both genders. The study aimed to conduct to understand the knowledge, attitude, and practice of primary healthcare physicians regarding colorectal cancer screening in Riyadh Second Health Cluster in the city of Riyadh, Saudi Arabia. A cross-sectional study design, probability proportional to size sampling at the cluster zones level and convenient sampling for the physicians, were used among physicians working in the primary healthcare centers in the city of Riyadh between October 2022 and November 2022. Of the 213 respondents, the mean age of the physician was 35, the majority were males (59%), Saudi Arabian nationality (60%), Resident Physicians (54%) and ≤ five years' work experience (45%). Sixty-four percent of the study participants believe that the majority of asymptomatic average-risk patients have to start the screening at the age of 45 years old. Ninety-seven percent believe that colorectal cancer screening for asymptomatic average-risk patients aged 45 years and older is effective. Ninety-two percent of the physicians perform colorectal cancer screening for asymptomatic average-risk patients aged 45 years. The mean knowledge score is 4.65 (SD=2.33) with a range of 0 to 10. The mean attitude score is 4.19 (SD=1.28) with a range of 0 to 6. The study found that the physicians had higher attitude and practice towards colorectal cancer screening and adequate knowledge towards colorectal cancer screening. The knowledge and attitude scores are associated with practicing colorectal cancer screening.

337 High Rates of Young-Onset Colorectal Cancer Incidence and Mortality in an Urban Tertiary Referral Center: A Case for Earlier Screening Colonoscopy

INTRODUCTION: The Multi Society Task Force for Prevention of Colorectal Cancer recommends initiating average risk screening for patients at age 45 in African Americans (AA) and at age 50 in all others. In the US, Colorectal Cancer (CRC) incidence and mortality has been increasing at a significant rate each year in patients younger than 50 years. This recent trend has not been insufficiently explored to inform modeling of CRC screening among asymptomatic average-risk patients who are younger than 50 years. Further study of the benefits and harms of screening in persons younger than 50 years is warranted. METHODS: We performed a retrospective analysis using TriNetX, a global federated health research network providing access to statistics on electronic medical records (diagnoses, procedures, medications, laboratory values, genomic information). Our analysis included all patients diagnosed with CRC from the period 2010 to 2019. We then excluded patients with a diagnosis of Inflammatory Bowel Disease and Hereditary Cancer Syndromes to identify only spontaneous CRC. We calculated the incidence per 100,000 persons of CRC in 5-year age groups between 20 and 59 years. We also performed Kaplan-Meier survival analysis in these groups. RESULTS: Between 2010 and 2019, there were 970 new cases of CRC in persons age 20 -59. The population consisted of 52% males, 48% females, race distribution: 54% Whites, 39% Blacks, 2% Asians, Other 5%. Mean age at diagnosis was 59. The incidence rates per 100 000 population were similar for the 40-45 age group and 45-49 age group (Figure 1). Patients aged less than 50 accounted for 33.7 percent of new CRC cases (Figure 2). Kaplan- Meier 5-year survival analysis showed lower rates of survival for patients aged 40-45 (47.1%) and 45-49 (43.9%), compared with patients aged 50-54 (54.8%) (Figure 3) CONCLUSION: Our study demonstrates high rates of CRC in patients less than 50 and this study may give further merit to the consideration of earlier screening in asymptomatic average risk patients. There is a definite need for large scale epidemiological studies to further evaluate this worrisome trend.

Adenoma detection rates in colonoscopies for positive fecal immunochemical tests versus direct screening colonoscopies

Recent guidelines propose higher adenoma detection rate (ADR) benchmarks for colonoscopies performed for positive results for fecal immunochemical tests (FIT), but this is based on low-quality evidence. We aimed to compare ADR, advanced ADR (AADR), and number of adenomas per colonoscopy (APC) in direct screening colonoscopy (DSC) versus FIT-positive colonoscopy (FITC) in a multicenter Asia-Pacific cohort to justify differential targets. Asymptomatic average-risk patients≥50 years of age who underwent screening colonoscopy directly or as follow-up for positive OC-Sensor FIT results were identified from 8 sites across the Asia-Pacific region. Overall, sex-specific ADR, overall AADR, and overall APC were compared between the 2 screening methods. Multivariable logistic regression was performed to adjust for confounding by differences in patient characteristics. Linear regression was used to correlate ADR with APC and to propose APC benchmarks. A total of 2901 (mean age, 60.1 years; 57% men) individuals had DSC, and 2485 (mean age, 62.8 years; 57% men) underwent FITC. Overall ADR (53.6% vs 37.5%; odds ratio [OR], 1.93; P< .001), male-specific ADR (61.6% vs 44.6%; OR, 2; P< .001), female-specific ADR (43.2% vs 28.2%; OR, 1.94; P< .001) and overall AADR (29.9% vs 4.9%; OR, 8.2; P< .001) in FITC were significantly higher than the corresponding values for DSC. Differences remained significant after adjustment for patient characteristics. ADR was strongly and positively correlated to APC, with an ADR of 45% and 35% correlating to an APC of ∼1 and ∼0.65. Results from this international multicenter cohort study provide early evidence that newly proposed higher ADR targets are justified as quality indicators for FITC.

Annual Fecal Occult Blood Testing can be Safely Suspended for up to 5 Years After a Negative Colonoscopy in Asymptomatic Average-Risk Patients.

Annual fecal occult blood testing (FOBT) is often continued in patients who have had a recent negative colonoscopy, despite recommendations to the contrary. This prospective study aimed to determine the proportion of patients with a positive FOBT who had adenomas and cancers on colonoscopy stratified according to the duration of time since the last negative colonoscopy. A total of 1,119 asymptomatic average-risk patients ≥50 years of age referred for a positive FOBT were prospectively identified and stratified by the duration of time since the last colonoscopy (never, >10 years, 5-10 years, or <5 years). The proportion of patients in each category with adenomas of any size, adenomas ≥10 mm, advanced neoplasms, and cancers was assessed. The mean age (68.9±9.6 years), sex (95.2% male), and race (48.1% white, 32.1% black, 15.6% Hispanic, and 4.2% other) did not differ between the four groups. Overall, adenomas of any size were detected in 42.8% of patients, adenomas ≥10 mm in 14.7%, advanced neoplasms in 20.7%, and cancers in 7.3%. Advanced neoplasms were detected in 30.4% of patients who have never had a colonoscopy, 27% in those who have had one greater than 10 years prior, 10.0% in 5-10 years prior, and 1.1% in less than 5 years prior. In asymptomatic average-risk patients with a negative colonoscopy within the last 5 years, the prevalence of adenomas is low, and no patient was diagnosed with cancer. These findings support the CDC recommendations to suspend annual FOBT for up to 5 years after a negative colonoscopy.

Annual fecal occult blood testing can be safely suspended for up to 5 years after a negative colonoscopy in asymptomatic average-risk patients.

Annual fecal occult blood testing can be safely suspended for up to 5 years after a negative colonoscopy in asymptomatic average-risk patients.

Effect of Screening Colonoscopy on Colorectal Cancer Incidence and Mortality

Colonoscopy is used widely for colorectal cancer (CRC) screening; however, its long-term impact on the incidence and mortality of CRC is not known. We assessed CRC incidence and mortality in a group of asymptomatic average-risk patients who underwent screening colonoscopy between 1989 and 1993 at a university hospital. By using standardized incidence ratios and standardized mortality ratios, we compared our observed CRC rates with expected rates from the Surveillance, Epidemiology, and End Results (SEER) data. The cohort comprised 715 patients (mean age, 61 +/- 6.5 y; 59% male; 95% Caucasian) with 10,492 patient-years of follow-up. There were 12 cases of CRC: 5 found at baseline and 7 found after a median follow-up period of 8 years (range, 3-16 y). When the first 2 years of follow-up were excluded, there were 7 incident cases of CRC (95% confidence interval [CI], 2-13) over 9075 person-years of follow-up. The expected number based on SEER data was 21. The incidence rate was 0.77 cases per 1000 person-years, and the standardized incidence ratio was 0.33 (95% CI, 0.10-0.62), consistent with a relative risk reduction in CRC incidence of 67%. Three patients died from CRC (95% CI, 0-9). The expected number of deaths based on SEER data was 9. The mortality rate was 0.29 per 1000 person-years, and the standardized mortality ratio was 0.35 (95% CI, 0.0-1.06), consistent with a relative reduction in CRC death of 65%. In this average-risk cohort, CRC incidence and mortality were reduced after screening colonoscopy. These results provide additional evidence for the effectiveness of colonoscopy as a primary CRC screening modality.

Screening for colorectal cancer in an asymptomatic average-risk population

AIM: To establish a risk prediction model and a risk scoring system for adenomatous polyps. METHODS: A cross-sectional study was performed in consecutive asymptomatic averagerisk patients. The potential risk factors were selected from the following aspects: general data, past medical history, personal history, dietary history, frequency of defecation, and menstrual history. The chi-square test and t-test were used for univariate analysis. Univariates with a P value equal to or lower than 0.25 were selected to perform multivariate analysis. Potential predictive factors were gradually selected using stepwise regression analysis to build a predictive model to estimate the risk of colorectal cancer. Scores were assigned to each predictive factor according to the β value to establish a scoring system to evaluate the precision and predictive ability of the model. RESULTS: The prevalences of polyps, adenoma, progressive adenocarcinoma and infiltrating cancer were 21.5%, 7.9%, 1.2% and 2.0%, respectively. The potential predictive factors identified for adenomatous polys included gender, education level, history of smoking and drinking, occupation, intake of fruit, milk, pickled and fried food as well as red meat, menstrual history, body mass index (BMI), and alcohol and tea consumption. These factors were used to build a risk predictive model for adenomatous polys. History of smoking, fruit intake, and red meat intake were three independent predictive factors for adenomatous polys. A risk scoring system for adenomatous polyps was also established: patients with a score more than 1 were considered to have adenomatous polyps. CONCLUSION: The risk prediction model and risk scoring system built in this study have relatively high diagnostic and predictive efficiency in an asymptomatic average-risk population. They are expected to be used to predict the risk of colorectal cancer among asymptomatic average-risk persons.

Predictive Value of a Positive Fecal Occult Blood Test Increases as the Severity of CKD Worsens

Because chronic kidney disease (CKD) may be associated with gastrointestinal bleeding from trivial mucosal lesions, we hypothesized that the predictive value of a positive fecal occult blood test (FOBT) result for clinically important colonic lesions would decrease as the stage of CKD worsened. We prospectively identified 1,225 consecutive asymptomatic average-risk patients who were referred for colonoscopy to evaluate a positive FOBT result. Using the Modification of Diet in Renal Disease equation, we estimated glomerular filtration rate (GFR) and staged the severity of CKD by using standard criteria as follows: normal/stage 1 (GFR > or = 90 mL/min/1.73 m2 [> or = 1.50 mL/s]), stage 2/3 (GFR 30 to 89 mL/min/1.73 m2 [0.50 to 1.48 mL/s]), and stage 4/5 (GFR < 30 mL/min/1.73 m2 [< 0.50 mL/s] or dialysis). Clinically important lesions were identified in 23.9% of 531 individuals with none/stage 1 CKD, 32.8% of 497 subjects with stage 2/3 CKD, and 42.6% of 197 patients with stage 4/5 CKD (P < 0.001). Compared with patients with none/stage 1 CKD, adjusted odds of identifying a clinically important lesion were 1.61 (95% confidence interval, 1.21 to 2.15) in subjects with stage 2/3 CKD and 2.33 (95% confidence interval, 1.62 to 3.36) in patients with stage 4/5 CKD. Prevalences of adenomas of 1 cm or greater (15.1% versus 20.1% versus 22.8%; P = 0.007), carcinomas (5.1% versus 10.1% versus 13.2%; P < 0.001), and vascular ectasias (1.7% versus 2.4% versus 6.1%; P = 0.003) increased with the severity of CKD. Contrary to our initial hypothesis, we found that the predictive value of a positive FOBT result for clinically important colonic lesions increased as the severity of CKD worsened.

Positive Predictive Value of Fecal Occult Blood Testing in Asymptomatic Average-Risk Patients with Varying Degrees of Chronic Kidney Disease

Background: Although patients with chronic kidney disease (CKD) are at increased risk of bleeding due to intrinsic platelet dysfunction, abnormal platelet-endothelial interaction, uremia, and other defects, it is unknown whether the performance characteristics of fecal occult blood testing (FOBT) are affected. Since CKD may be associated with gastrointestinal bleeding from trivial mucosal lesions, we hypothesized that the positive predictive value (PPV) of FOBT for clinically important lesions would decrease as the stage of CKD worsens. Methods: Consecutive asymptomatic, average-risk patients ≥50 years of age who were referred for evaluation of a positive FOBT were prospectively identified. Prior to colonoscopy, all patients were interviewed by a research assistant who obtained detailed demographic and clinical data. Colonic lesions which were considered clinically important included cancer, adenomatous polyps ≥1 cm, active colitis, colonic ulcers ≥1 cm, and vascular ectasias that numbered 5 or more or were ≥8mm in diameter. Using the Modified Diet in Renal Disease (MDRD) equation, we estimated the glomerular filtration rate (GFR) in ml/min/1.73m2 and staged the severity of CKD using standard criteria as follows: normal/stage 1 (GFR ≥ 90), stage 2/3 (GFR 30 - 89), and stage 4/5 (GFR <30 or dialysis). Results: Among the 1,225 patients enrolled, the mean age was 68.4±9.6 years; 539 were white, 427 were black, 210 were Hispanic, and 49 were “other” racial groups. The stage of CKD was none/stage 1 in 531 patients, stage 2/3 in 497, and stage 4/5 in 197 subjects. Colonoscopy was complete to the cecum in 96.6% of patients and did not differ according to the stage of CKD (p = 0.18). Clinically important lesions were identified in 23.9% of patients with none/stage 1 CKD, 32.8% of those with stage 2/3 CKD, and 42.6% of subjects with stage 4/5 CKD (p < 0.001). Compared to patients with none/stage 1 CKD, the odds of identifying a clinically important lesion was 1.61 (95% CI, 1.21 - 2.15) in patients with stage 2/3 CKD and 2.33 (95% CI, 1.62 - 3.36) in subjects with stage 4/5 CKD after adjusting for age, sex, race, NSAID use, aspirin use, alcohol use, and smoking. The prevalence of adenomas ≥1 cm (15.1% vs 20.1% vs 22.8%, p = 0.007), cancers (5.1% vs 10.1% vs 13.2%, p < 0.001), and vascular ectasias (1.7% vs 2.4% vs 6.1%, p = 0.003) increased with the severity of CKD. Conclusions: Contrary to our initial hypothesis, we found that the PPV of FOBT for clinically important colonic lesions increases as the severity of CKD worsens. Complete colonoscopy should be offered to all individuals with a positive FOBT, regardless of the stage of CKD.

Annual Fecal Occult Blood Testing Can Be Safely Suspended for Up To 5 Years After a Negative Colonoscopy in Asymptomatic Average-Risk Patients

Background: In clinical practice, physicians often continue to perform annual fecal occult blood testing (FOBT) in patients who have had a recent negative colonoscopy. The Centers for Disease Control and Prevention (CDC) discourages this practice because it increases the likelihood of false positive results, and they recommend suspending annual FOBT for 5-10 years after a negative total colon exam. However, these recommendations were based on “expert” opinion. The aim of this prospective study was to determine the proportion of patients with a positive FOBT who had adenomas and cancers on colonoscopy stratified according to duration of time since the last negative colonoscopy. Methods: 1,119 asymptomatic average-risk patients ≥ 50 years of age who were referred for colonoscopy to evaluate a positive FOBT were prospectively identified. A detailed medical history was obtained from all patients prior to colonoscopy, and subjects were stratified by the duration of time since last colonoscopy (never had a colonoscopy, negative colonoscopy >10 years, 5-10 years, or >5 years). The proportion of patients in each category with adenomas of any size, adenomas = 10 mm, advanced neoplasms (adenomas = 10 mm or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or cancer), and cancers was assessed. Results: The mean age (68.9 ± 9.6 years), sex (95.2% male), and race (48.1% white, 32.1% black, 15.6% Hispanic, and 4.2% other) did not differ between the 4 groups. Colonoscopy was complete to the cecum in 97.1% of patients and was similar in all 4 groups (P = 0.61). Overall, adenomas of any size were detected in 42.8% of patients, adenomas =10 mm in 14.7%, advanced neoplasms in 20.7%, and cancers in 7.3%. Conclusions: In asymptomatic average-risk patients who have had a negative colonoscopy within the last 5 years, the prevalence of adenomas is low and no patient was diagnosed with cancer. Although these findings support the CDC recommendations to suspend annual FOBT for up to 5 years after a negative total colon examination, suspending FOBT for up to 10 years may miss potentially curable lesions.

PREDICTIVE VALUE OF A POSITIVE FECAL OCCULT BLOOD TEST OBTAINED AT THE TIME OF DIGITAL RECTAL EXAMINATION

Purpose: Clinicians often screen for colorectal cancer by testing stool for occult blood at the time of digital rectal examination (DRE). However, this screening method has been discouraged because it is thought to increase the false-positive rate of the fecal occult blood test (FOBT). The aim of this prospective study was to compare the predictive value of a positive FOBT obtained by testing a single stool sample at the time of DRE with the predictive value of a positive test obtained by the recommended method of testing 3 consecutive stool samples at home. Methods: Asymptomatic average-risk patients 50 years of age and older who were referred for colonoscopy to evaluate a positive FOBT obtained by DRE or at-home testing from June 1997 to May 2004 were prospectively identified. FOBT was performed using Hemoccult II test kits without rehydration. Colonic lesions which were considered clinically important included cancer, adenomatous polyps ≥ 1 cm, active colitis, colonic ulcers ≥ 1 cm, and vascular ectasias that numbered 5 or more or ≥ 8 mm in diameter. Results: A total of 611 patients (mean age 68.9 ± 9.7 years) met the entry criteria and were evaluated by colonoscopy for a positive FOBT obtained by DRE (n = 222) or at-home testing (n = 389). The baseline characteristics, including age, gender, and race, did not differ significantly between the two groups. Colonoscopy was complete to the cecum in 95.9% of the DRE group and 96.4% of those in the at-home testing group (p = 0.83). Although there was a trend towards a higher prevalence of clinically important lesions in the DRE group (32.4% vs. 25.7%, p = 0.08), there were no statistically significant differences in the proportion of patients with adenomatous polyps >1 cm (14.9% vs. 16.2%, p = 0.66) or colorectal cancer (9.5% vs. 8.0%, p = 0.53) between the DRE and at-home testing groups. Conclusions: In asymptomatic average-risk patients, the predictive value of a positive FOBT obtained by DRE was no different from that obtained by traditional at-home testing. These findings support the practice of performing full colonoscopy for the evaluation of a positive FOBT regardless of the method of stool collection.

Virtual colonoscopy—finally a credible contender

Virtual colonoscopy—finally a credible contender

Importance of Hyperplastic Polyps and Adenomas 5mm or Less in Diameter That Are Detected by Screening Flexible Sigmoidoscopy

Background: The need for full colonoscopy in patients with hyperplastic polyps or adenomas 5mm or less in diameter that are detected by screening flexible sigmoidoscopy (FS) is controversial. The aim of this study was to determine the prevalence of proximal colonic neoplasms in a large cohort of patients with distal polyps detected by screening FS. Methods: Consecutive asymptomatic patients at average-risk for colorectal cancer who were referred for screening FS were prospectively enrolled from 1/98 through 10/03. A detailed medical history was obtained from all patients prior to FS, and colonoscopy was offered to all subjects with polyps on FS. Polyps detected by FS were classified as hyperplastic, diminutive adenomas (≤ 5mm in diameter), small adenomas (6 - 9 mm in diameter), large adenomas (≥ 10mm in diameter), or cancers. In patients with more than one polyp, classification was based on the most advanced lesion. For each type of lesion on FS, we determined the proportion of patients who had any adenomas, advanced colonic neoplasms, or cancers detected by colonoscopy in the proximal colon. Advanced colonic neoplasms were defined as adenomas ≥ 10mm in diameter or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or cancer. Results: A total of 2,084 patients (mean age 66.5 ± 9.4 years) were enrolled, and the mean depth of insertion of the sigmoidoscope was 57.7 ± 7.1 cm. One or more polyps were detected in 491 of the 2,084 patients (23.6%), and the most advanced lesion on FS was classified as a hyperplastic polyp in 8.4% of patients, adenoma ≤ 5mm in 6.4%, adenoma 6 - 9 mm in 3.2%, adenoma ≥ 10mm in 3.2%, and cancer in 0.5% of subjects. Of the 491 patients with a polyp on FS, 482 of these subjects (98.2%) underwent colonoscopy and 97.5% of these examinations were complete to the cecum. Conclusions: There was a substantial prevalence of proximal adenomas and advanced colonic neoplasms in asymptomatic average-risk patients with distal hyperplastic polyps and adenomas ≤ 5mm in diameter. Colonoscopy should be offered to individuals found to have hyperplastic or diminutive adenomas on FS.

On-site screening sigmoidoscopy promotes long-term utilization but fails as a venue for training primary care endoscopists

"Academic detailing" is an effective strategy for promoting the use of screening sigmoidoscopy by primary care physicians. The primary objectives of this study were to determine whether the sustained presence of an "outside" university-based gastroenterologist performing on-site screening sigmoidoscopy promoted long-term utilization and whether the provision for on-site sigmoidoscopy was an effective venue for training primary care endoscopists. Nine urban community health centers, including 4 intervention and 5 control sites, participated in a nonrandomized controlled trial conducted over 3 years. By the end of year 3, overall self-reported use of screening sigmoidoscopy increased by 61% for the intervention group vs. only 25% for the comparison group (P = 0.001). Ninety-seven percent of those reporting compliance referred 1 or more asymptomatic average-risk patients for screening examinations. Only 2 of 83 (2.4%) eligible providers completed on-site training and continued performing screening examinations independently. The major barriers to participation included lack of interest, lack of time to learn or perform sigmoidoscopy, concerns about technical competence, and lack of need because of on-site availability. Maintenance of on-site screening sigmoidoscopy services performed by an outside gastroenterologist promotes long-term utilization but fails as venue for training primary care endoscopists. Alternative strategies for expanding capacity are needed.

Prevalence of proximal colonic polyps in average-risk asymptomatic patients with negative fecal occult blood tests and flexible sigmoidoscopy

Background: Proximal colonic adenomas were found in 13% to 37% of patients without distal adenomas who underwent colonoscopy. Fiberoptic flexible sigmoidoscopy (FFS) was not performed prior to colonoscopy in all studies except one. The proximal colon at colonoscopy was defined as that portion of the colon proximal to either the descending-sigmoid junction or 60 cm from the anus while withdrawing the colonoscope. These estimates may not reflect exact colonic location when a 60 cm length sigmoidoscope is fully inserted. Therefore, the aim of our study was to determine the prevalence of proximal colonic neoplasms in asymptomatic patients with average risk for colon cancer, aged 50 years and over, with negative fecal occult blood tests and without adenomas at FFS. Methods: Colonoscopy was performed in 80 patients without and 95 patients with adenomas at FFS. Polypectomy was done using hot biopsy forceps or snare cautery. Results: Twenty-four proximal colonic adenomas (19 <1 cm and 5 ≥1 cm) were found in 18 of 80 patients (23%) with normal FFS compared with 39 proximal colonic adenomas (32 <1 cm and 7 ≥1 cm), in 28 of 95 patients (29%) with adenomas at FFS ( p = 0.31). In patients with normal FFS, there were 20 tubular, 2 tubulovillous, and 2 villous (1 with severe dysplasia) adenomas. In patients with adenomas at FFS, there were 31 tubular, 5 tubulovillous, and 3 villous (1 with severe dysplasia) adenomas. Conclusions: Proximal colonic adenomas are found in up to one fourth of asymptomatic average-risk patients with negative fecal occult blood test and both with and without adenomas at FFS. The adenomas in both groups have similar size, histology, and location. Severe dysplasia is rarely present. (Gastrointest Endosc 1996;44:112-7.)

Virtual endoscopy: is it reality?

Virtual endoscopy: is it reality?

COLORECTAL CANCER SCREENING

The decision whether to launch a screening program in asymptomatic patients of average risk for colorectal cancer and the selection of the appropriate protocol for screening are complex issues. There are still many unanswered questions. Many organizations such as the American Cancer Society, the World Health Organization Collaborating Center for the Prevention of Colorectal Cancer, and the U.S. National Cancer Institute advocate screening with annual Hemoccult tests and screening with flexible sigmoidoscopy every 3 to 5 years in patients more than 50 years of age. The U.S. Preventive Services Task Force, the Canadian Task Force on Periodic Health Examination, and the International Union Against Cancer have not recommended screening asymptomatic average-risk patients for colorectal cancer. One study showed a small but significant benefit (3 per 1000) of the rehydrated annual Hemoccult test in reducing mortality from colorectal cancer. To embark on a mass screening strategy as recommended, however, would require significant costs, increases in physician training, improved access to the requisite technology, and enhancements in patient and physician compliance. Furthermore, the high false-positive rates of the rehydrated Hemoccult tests would lead to many unnecessary tests, causing greater expense as well as patient discomfort and anxiety. It is, therefore, premature to recommend mass screening for colorectal cancer in asymptomatic individuals at this time. Further research is needed to identify risk factors (such as genetic markers) better and to develop and evaluate screening strategies targeted at those with high risk for colorectal cancer. In the meantime, efforts at primary prevention for the general population should be increased (through nutrition and exercise). Patients over the age of 50 who desire screening should be given information of the benefits and risks of screening and together with their physicians decide on a screening strategy that suits their needs and values.