Air-contrast Barium Enema Research Articles

Analysis of air contrast barium enema, computed tomographic colonography, and colonoscopy: prospective comparison

<h2>Summary</h2><h3>Background</h3> The usefulness of currently available colon imaging tests, including air contrast barium enema (ACBE), computed tomographic colonography (CTC), and colonoscopy, to detect colon polyps and cancers is uncertain. We aimed to assess the sensitivity of these three imaging tests. <h3>Methods</h3> Patients with faecal occult blood, haematochezia, iron-deficiency anaemia, or a family history of colon cancer underwent three separate colon-imaging studies—ACBE, followed 7–14 days later by CTC and colonoscopy on the same day. The primary outcome was detection of colonic polyps and cancers. Outcomes were assessed by building an aggregate view of the colon, taking into account results of all three tests. <h3>Findings</h3> 614 patients completed all three imaging tests. When analysed on a per-patient basis, for lesions 10 mm or larger in size (n=63), the sensitivity of ACBE was 48% (95% CI 35–61), CTC 59% (46–71, p=0·1083 for CTC <i>vs</i> ACBE), and colonoscopy 98% (91–100, p<0·0001 for colonoscopy <i>vs</i> CTC). For lesions 6–9 mm in size (n=116), sensitivity was 35% for ACBE (27–45), 51% for CTC (41–60, p=0·0080 for CTC <i>vs</i> ACBE), and 99% for colonoscopy (95–100, p<0·0001 for colonoscopy <i>vs</i> CTC). For lesions of 10 mm or larger in size, the specificity was greater for colonoscopy (0·996) than for either ACBE (0·90) or CTC (0·96) and declined for ACBE and CTC when smaller lesions were considered. <h3>Interpretation</h3> Colonoscopy was more sensitive than other tests, as currently undertaken, for detection of colonic polyps and cancers. These data have important implications for diagnostic use of colon imaging tests. Published online December 17, 2004 http://image.thelancet.com/extras/04art11289web.pdf

Unbiased studies are needed before virtual colonoscopy can be dismissed

Published online December 17, 2004. http://image.thelancet.com/extras/04cmt427web.pdf Analysis of air contrast barium enema, computed tomographic colonography, and colonoscopy: prospective comparisonColonoscopy was more sensitive than other tests, as currently undertaken, for detection of colonic polyps and cancers. These data have important implications for diagnostic use of colon imaging tests. Published online December 17, 2004 http://image.thelancet.com/extras/04art11289web.pdf Full-Text PDF

Analysis of air contrast barium enema, computed tomographic colonography, and colonoscopy: prospective comparison

The usefulness of currently available colon imaging tests, including air contrast barium enema (ACBE), computed tomographic colonography (CTC), and colonoscopy, to detect colon polyps and cancers is uncertain. We aimed to assess the sensitivity of these three imaging tests. Patients with faecal occult blood, haematochezia, iron-deficiency anaemia, or a family history of colon cancer underwent three separate colon-imaging studies--ACBE, followed 7-14 days later by CTC and colonoscopy on the same day. The primary outcome was detection of colonic polyps and cancers. Outcomes were assessed by building an aggregate view of the colon, taking into account results of all three tests. 614 patients completed all three imaging tests. When analysed on a per-patient basis, for lesions 10 mm or larger in size (n=63), the sensitivity of ACBE was 48% (95% CI 35-61), CTC 59% (46-71, p=0.1083 for CTC vs ACBE), and colonoscopy 98% (91-100, p<0.0001 for colonoscopy vs CTC). For lesions 6-9 mm in size (n=116), sensitivity was 35% for ACBE (27-45), 51% for CTC (41-60, p=0.0080 for CTC vs ACBE), and 99% for colonoscopy (95-100, p<0.0001 for colonoscopy vs CTC). For lesions of 10 mm or larger in size, the specificity was greater for colonoscopy (0.996) than for either ACBE (0.90) or CTC (0.96) and declined for ACBE and CTC when smaller lesions were considered. Colonoscopy was more sensitive than other tests, as currently undertaken, for detection of colonic polyps and cancers. These data have important implications for diagnostic use of colon imaging tests.

CT Colonography vs. Standard Colonoscopy

In previous studies of computed tomographic colonography (CTC or virtual colonoscopy), estimates of its sensitivity for colon polyps and cancers have varied widely. In the current study, researchers in the U.S. directly compared the accuracy of CTC with air-contrast barium enema (ACBE) and colonoscopy in 614 subjects (mean age, 57; 70% men) who …

The evaluation of rectal bleeding in adults

Though primary care patients commonly present with rectal bleeding, the optimal evaluation strategy remains unknown. To compare the cost-effectiveness of four diagnostic strategies in the evaluation of rectal bleeding. Cost-effectiveness analysis using a Markov decision model. Systematic review of the literature, Medicare reimbursement data, Surveillance, Epidemiology, and End Results (SEER) Cancer Registry. Patients over age 40 with otherwise asymptomatic rectal bleeding. The patient's lifetime. Modified societal perspective. Watchful waiting, flexible sigmoidoscopy, flexible sigmoidoscopy followed by air contrast barium enema (FS+ACBE), and colonoscopy. Incremental cost-effectiveness ratio. The incremental cost-effectiveness ratio for colonoscopy compared with flexible sigmoidoscopy was 5,480 dollars per quality-adjusted year of life saved (QALY). Watchful waiting and FS+ACBE were more expensive and less effective than colonoscopy. The cost of colonoscopy was reduced to 1,686 dollars per QALY when age at entry was changed to 45. Watchful waiting became the least expensive strategy when community procedure charges replaced Medicare costs, when age at entry was maximized to 80, or when the prevalence of polyps was lowered to 7%, but the remaining strategies provided greater life expectancy at relatively low cost. The strategy of FS+ACBE remained more expensive and less effective in all analyses. In the remaining sensitivity analyses, the incremental cost-effectiveness of colonoscopy compared with flexible sigmoidoscopy never rose above 34,000 dollars. Colonoscopy is a cost-effective method to evaluate otherwise asymptomatic rectal bleeding, with a low cost per QALY compared to other strategies.

Prospective comparison of air-contrast barium enema and colonoscopy in patients with fecal occult blood: a pilot study

The utility of air-contrast barium enema and colonoscopy for evaluation of the colon has been debated. Air-contrast barium enema is less expensive and invasive than colonoscopy, but it also is less sensitive and specific. Further, although air-contrast barium enema may be less painful than colonoscopy, it often is poorly tolerated by patients. Thus, this study compared the sensitivity and the specificity of air-contrast barium enema and colonoscopy for detection of colonic lesions in patients with fecal occult blood. Over a 30-month period, patients with fecal occult blood were recruited. Patients underwent standard air-contrast barium enema, followed by colonoscopy 7 to 14 days later. Colonoscopists were blinded to the results of air-contrast barium enema until the colonoscopy was completed, after which the results were disclosed. If the findings were discrepant, colonoscopy was repeated. A total of 100 patients were evaluated. Nine air-contrast barium enemas were reported to be inadequate, and the cecum was not intubated at colonoscopy in two patients. In the remaining patients, 5 cancers were identified (1 each cecum, transverse colon, descending colon, sigmoid colon, and rectum) by both studies. Sixty-six polypoid lesions were identified in 30 patients. Diverticula were identified in 42 patients by air-contrast barium enema and in 18 patients by colonoscopy. Air-contrast barium enema detected 3 of 36 polypoid lesions 5 mm or less in diameter, 5 of 15 adenomas 6 to 9 mm in size, and 4 of 15 adenomas 10 mm or greater in diameter (sensitivity 8%, 33%, and 27%, respectively). After excluding patients with diverticula, air-contrast barium enema detected 3 of 7 adenomas 10 mm or greater in size. Overall, 12 polypoid lesions or filling defects were identified by air-contrast barium enema that could not be verified by colonoscopy. The specificity of air-contrast barium enema for lesions 1.0 cm or greater in size was 100%; for those 6 mm or greater, it was 97%. Air-contrast barium enema accurately detects colon cancer and diverticula. Its sensitivity for detection of polypoid lesions or adenomas is poor and was confounded by the presence of diverticula.

An interesting case of crohn’s disease

Purpose: 48 y.o. AAF admitted with abdominal pain and 4 years history of ileocolonic Crohn's disease (CD). Initial diagnostic colonoscopy disclosed mild chronic ileocolonic inflammation. The patient was treated with Asacol with prompt resolution of her complains and no relapses over next 4 years. She did not follow-up. Several days prior to admission, the patient developed right lower quadrant abdominal pain, nausea and vomiting. The CT scan showed inflammation in the right lower quadrant with some thickening of the terminal ileum, but no abscesses or fluid collections. Upper GI and small bowel series demonstrated multiple fistulous tracks consistent with CD. Terminal ileum was thickened with abnormal contour and folds. She was treated with Prednisone, Cipro, Flagyl, TPN, bowel rest and responded to treatment well and was discharged. Colonoscopy showed areas of pseudopolyp formation with scarring and exudates at 25 cm, fistulous tract with marked surrounding scarring and edema at 40 cm and significant fixed looping between 25 and 40 cm. Air contrast barium enema revealed multiple colo-colonic fistulae. She has been maintained on Remicade therapy and is currently doing well.

CT colonography (‘virtual colonoscopy’): Is it ready for colorectal cancer screening?

CT colonography (‘virtual colonoscopy’): Is it ready for colorectal cancer screening?

Screening for colorectal cancer: the cost to find an advanced adenoma

OBJECTIVE: Cancer Care Ontario has recommended a program to screen for colorectal cancer using fecal occult blood testing (FOBT). Patients who test positive on FOBT will require further investigation. We examined the cost of finding an advanced adenoma in these patients using four different strategies. METHODS: Using decision analysis software (DATA 3.5, TreeAge Software, Boston, MA), we considered four strategies for evaluating patients referred for a positive FOBT: 1) flexible sigmoidoscopy to the splenic flexure, 2) flexible sigmoidoscopy with air contrast barium enema (ACBE), 3) virtual colonoscopy, and 4) colonoscopy. If an adenoma was found in any of the first three methods, colonoscopy and polypectomy were performed. An advanced adenoma was defined as a villous adenoma, tubular adenoma ≥10 mm, high grade dysplasia, or cancer. Values for probabilities, test characteristics and costs ($CDN) were estimated from a MEDLINE literature review, local costs, and OHIP fee codes. Patients with adenomas identified as well as direct medical costs from a third party payer perspective were calculated. RESULTS: Assuming a probability of adenoma of 16.9%, the cost for each strategy (compared to no investigation) was as follows: flexible sigmoidoscopy to the splenic flexure, $226; flexible sigmoidoscopy with ACBE, $424; virtual colonoscopy, $597; and colonoscopy, $387. The cost to clear a patient of adenoma(s) was $1930, $2840, $3681, and $2290, respectively. Despite being most cost-effective, the sigmoidoscopy strategy was predicted to detect 69% of cases of advanced adenomas. The radiological strategies would be less expensive if ACBE cost less than $115 or virtual colonoscopy cost less than $291. The colonoscopy strategy was more cost-effective if the probability of an adenoma was ≥33.5%. When the incremental costs were considered to investigate 1000 patients, virtual colonoscopy and sigmoidoscopy with ACBE were both more costly then colonoscopy, and neither detected as many cases of advanced adenomas. CONCLUSION: Improved access to colonoscopy seems to be the preferred approach to deal with increased referrals.

Virtual colonoscopy (CT and MR colonography)

Colorectal cancer is the second most common cause of death due to cancer in the United States. Most colorectal cancers arise from pre-existing benign adenomatous polyps. Detection and removal of these polyps has been found to significantly decrease the subsequent development of colon carcinoma. 1 Winawer SJ Zauber AG Ho MN O'Brien MJ Gottlieb LS Sternberg SS et al. Prevention of colorectal cancer by colonoscopic polypectomy. The National Polyp Study Workgroup. N Engl J Med. 1993; 329: 1977-1981 Crossref PubMed Scopus (3830) Google Scholar However, the majority of individuals who are recommended to undergo colorectal cancer screening do not participate in testing and compliance rates remain low. Current colorectal cancer screening options include fecal occult blood testing, flexible sigmoidoscopy, air-contrast barium enema, and fiberoptic colonoscopy. Fecal occult blood testing (FOBT) is noninvasive and is the most widely available and least expensive test, but has suboptimal sensitivity and prevents the fewest cancers. Fiberoptic colonoscopy is very sensitive for colorectal lesions, but is the most invasive and costly.

Comparison of patients' experiences during imaging tests of the colon

Background: Physical discomfort, anxiety, embarrassment, and other aspects of patient experience impact on future compliance for colonic imaging tests. Therefore, a prospective study was performed comparing patient experiences during air contrast barium enema (ACBE), flexible sigmoidoscopy, and colonoscopy. Methods: Immediately after each procedure, patients completed a questionnaire assessing pretest anxiety, difficulty with preparation, pain, cramping, bloating, overall discomfort, loss of dignity, willingness to repeat the test, and overall satisfaction. A follow-up questionnaire was administered within 48 hours. Nurses and physicians also completed questionnaires to assess the provider impression of patient experience. Results: Four hundred ten patients (80 ACBE, 202 sigmoidoscopy, 128 colonoscopy) were prospectively enrolled. Sigmoidoscopy caused more pain than ACBE (Odds ratio [OR] 2.64: 95% CI [1.63, 4.27]) or colonoscopy (OR 1.83: 95% CI [1.21, 2.77]). ACBE and colonoscopy did not differ in the degree of pain. Although overall satisfaction appeared to be similar for all tests, patients were less willing to repeat ACBE than sigmoidoscopy (OR 1.85: 95% CI [1.13, 3.02]) or colonoscopy (OR 1.82: 95% CI [1.07, 3.09]). Initial and follow-up pain ratings by patients were highly correlated (Spearman correlation 0.81); however, correlation of pain assessments between staff and patients was poor (Spearman correlation 0.48). Conclusions: Sigmoidoscopy was more painful than other colonic imaging modalities. Although ACBE and colonoscopy caused similar pain, patients were less willing to repeat ACBE. In aggregate, the data suggest that patients perceive colonoscopy as the most acceptable colonic imaging procedure. Better methods are required to allow staff to adequately assess discomfort experienced by patients during these procedures. (Gastrointest Endosc 2001;54:67-74.)

Chemoprevention of colon cancer.

Adenocarcinoma of the large bowel presents a major public health problem. It affects about 1 person in 20 in the United States and Western countries [1]. It is the second most common cause of cancer death in American males, and the third most common cause in American females. When diagnosed and treated in its early stages, it is a highly curable disease. However, only half of all patients who present with colorectal cancer are cured by primary resection [2]. Primary prevention through the identification and eradication of risk factors responsible for the development of colorectal cancer is an area of active research throughout the world. Both environmental and genetic factors have been causally related to the development of colorectal cancer. Secondary prevention, by identifying premalignant lesions through screening techniques such as endoscopy, fecal occult blood testing, air-contrast barium enema, and CT colonography may potentially lead to a dramatic reduction in mortality. As a result of our improved understanding of the pathogenesis of colorectal cancer, the role of chemoprevention, either as primary or secondary prevention, and the targets for prevention, have been more readily defined.KeywordsColorectal CancerColon CancerBile AcidFamilial Adenomatous PolyposisAdenomatous Polyposis ColiThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

A colposcopic approach to an endometriotic nodule in the recto vaginal septum under laparoscopic control

The surgical treatment of endometriotic nodules in the recto vaginal septum is aimed at removing the deeply infiltrating fibro muscular and abnormal glandular tissue, in order to relieve pelvic pain. The laparoscopic approach to the recto vaginal septum is difficult and potentially dangerous. We describe a new mode of access using a combination of laparoscopy and colposcopy. A 20-year-old woman presented with dyspareunia and dyschezia. Vaginal examination revealed a tender nodule, measuring 1.5 2 2 cm, in the posterior vagina wall. The endometriotic deposit was positioned at the top of the recto vaginal septum, extending into the posterior vaginal fornix. An air-contrast barium enema and vaginogran (lateral view) excluded a lesion that had penetrated the full thickness of the rectal wall. We carried out colposcopic CO 2 laser ablation of the nodule under laparoscopic control. 'Chocolate fluid' spilled from the lesion and the entire nodule was vaporised until normal tissue was reached. The patient was reviewed 3 and 6 months following the operation, and her symptoms had resolved. The colposcope allows an approach into an area of the pelvis that is usually difficult to access.

The difficulty of urethral anastomosis in sigmoid neobladder--the role of preoperative X-ray of an air-contrast barium enema

Sigmoid neobladder (Reddy method) is one of the representative neobladder after radical cystectomy. Occasionally we experienced difficulty on urethral anastomosis in sigmoid neobladder. Here we investigated preoperative X-ray of air-contrast barium enema and clarified what type could be easily anastomosed in sigmoid neobladder. We performed five cases of total cystectomy with sigmoid neobladder replacement. Of the five, we can easily make a urethral anastomsis in three cases but not easily in other two cases. We investigated sigmoid colon length, it's internal diameter, it's form and it's mobility that was substituted for elevation level of rectosigmoid using preoperative X-ray of air-contrast barium enema. We also studied seventy five cases of X-ray of air-contrast barium enema who visited our hospital with various complaints such as lower abdominal pain. The length of three cases with easily anastomosed were 45.7 cm in diameter other two cases 33.5 cm in diameter.(over all 47.5 cm) The internal diameter were 49 mm and 33.5 mm respectively.(over all 44.4 mm) It was considered that Reddy method was indicated who had at least averaged sigmoid colon length and internal size. Sigmoid colon form were classified into 3 groups (type N. type l and others). There were no difference on colon length regarding sigmoid form, but others was considered to be improper form because significant difference was observed between type N and others in internal diameter. Three cases with easily anastomosed demonstrated a positive correlation of the elevation of the sigmoid colon over promontorium in the air contrast barium enema, other two cases negative. The elevation cases of the sigmoid colon in X-ray of air contrast barium enema had long sigmoid colon than other types.(p < 0.0001) Tha mean length of them was 51.6 cm in diameter. Sigmoid neobladder was at least indicated in men who had averaged sigmoid colon length. The sigmoid colon elevation sign in X-ray of air contrast barium enema did not require the measurement of sigmoid colon length and that sign implied good indication for sigmoid neobladder.

Diagnostic testing following fecal occult blood screening in the elderly.

Screening with a fecal occult blood test (FOBT) has been shown to reduce colorectal cancer mortality in controlled trials. Recently, Medicare approved payment for FOBT screening. We evaluated the pattern of diagnostic testing following the initial FOBT in elderly Medicare beneficiaries. Such follow-up testing would in the long run influence both the cost and the benefit of widespread use of FOBT. Using Medicare's National Claims History System, we identified 24 246 Americans 65 years old or older who received FOBT at physician visits between January 1 and April 30, 1995. Prior to FOBT, these people had no evidence of any conditions for which FOBT might be used diagnostically. We examined relevant diagnostic testing in this cohort during the subsequent 8 months and determined what proportion of those received an evaluation recommended by the American College of Physicians. For every 1000 Medicare beneficiaries who received FOBT, 93 (95% confidence interval = 89-96 per 1000) had positive findings and relevant testing in the subsequent 8 months. Of these, 34% had the recommended evaluation of either colonoscopy or flexible sigmoidoscopy with an air-contrast barium enema. Another 34% received a partial colonic evaluation with either flexible sigmoidoscopy or a barium enema. The remaining 32% received other gastrointestinal (GI) testing without evaluation of the colonic lumen: computed tomography or magnetic resonance imaging of the abdomen (15%), upper GI series (10%), carcinoembryonic antigen (7%), and upper endoscopy (2%). Restricting the analysis to testing performed within 2 months of the initial FOBT yielded similar results. Following FOBT, many Medicare beneficiaries get further diagnostic testing, but only a small proportion receives the recommended evaluation. With this pattern of practice, population screening is likely to be more costly and less effective than estimated from controlled trials.

Colonic polyps in children: frequently multiple and recurrent.

A retrospective chart review on 77 children and adolescents (45 males and 32 females) with colorectal polyps seen over a 15-year period (1980-1994) was undertaken. Their presenting symptoms, demographic data, methods of diagnosis, pathologic diagnosis, and outcome were assessed. The age at presentation varied from 6 months to 19 years (mean age 77 months), 66.2% presenting under 6 years of age. The presenting symptoms were rectal bleeding in 71 patients, mass per rectum in 12, abdominal pain in nine, diarrhea in nine, vomiting in two, and one patient was asymptomatic. Air contrast barium enema was confirmatory in 41/54 patients (76%). Polyps were palpable in 16 patients during the rectal examination. A single polyp was present in 50 patients, whereas two to five polyps were present in 20 patients, and more than five in seven patients. Successful endoscopic removal was accomplished in 71/73 patients (97.3%). In 83.1% of patients polyps were located in the rectosigmoid area and in 32.5% polyps occurred proximal to the sigmoid colon. However, multiple polyps in the same location or at other locations were also present simultaneously. Recurrence was observed in five of 63 patients (7.9%) with juvenile polyps, in one patient with infantile polyposis, and in one with solitary adenomatous polyp. We conclude that a full colonoscopic evaluation should be performed in all patients with suspected polyps if feasible, for multiple polyps occurred in 35% of children without polyposis syndromes in this series. Parents of patients with more than three polyps and/or a family history of juvenile polyposis should be warned regarding the possibility of an increased risk of malignancy in future if polyps continue to recur.

Prospective comparison of air-contrast barium enema and colonoscopy in patients with fecal occult blood

Prospective comparison of air-contrast barium enema and colonoscopy in patients with fecal occult blood

Genetic Testing in Hereditary Colorectal Cancer

<h3>CASE PRESENTATION</h3> A 29-year-old woman presented to her family physician with a 2-month history of 30 to 44 mL (2-3 tbsp) of bright red blood per rectum with every bowel movement. She was referred to a surgeon, who performed anoscopy and gave her a diagnosis of hemorrhoidal bleeding. She underwent hemorrhoidal surgery of unknown type. The patient again sought medical attention 3 months later, complaining of persistent and unchanged rectal bleeding. She had no change in bowel habits, weight loss, or family history of colorectal cancer or polyps. Examination of her skin did not show osteomas, lipomas, or epidermoid cysts. Direct ophthalmoscopic examination revealed no pigmentation of the retinal epithelium. Abdominal examination was normal. A stool sample taken during rectal examination tested guaiac positive. The results of an upper gastrointestinal tract barium series were normal, but air contrast barium enema showed multiple filling defects throughout the colorectum. Subsequent colonoscopy revealed

The modern medical management of acute, severe ulcerative colitis.

The management of patients with acute, severe ulcerative colitis requires careful in-hospital assessment of the patient and the coordinated treatment of a team of experienced gastroenterologists and surgeons. Complete understanding of the potential complications and their management, especially toxic megacolon, is essential. We review the current medical arsenal and advocate a standardized approach to management that includes continuous, high dose intravenous hydrocortisone, more aggressive use of topical steroids as well as feeding the patients and continuing (but not initiating) oral 5-aminosalicylic acid (5-ASA) agents. For those patients whose disease proves refractory to intravenous steroids, intravenous cyclosporin (with an acute response rate of 82%) is an essential component in the medical management of these patients. Antibiotics should be used only when specifically indicated. Total parenteral nutrition has not been shown to be helpful in the acute setting. Air contrast barium enema and colonoscopy have been used to predict response but may be dangerous diagnostic modalities in these acutely ill patients and are no better than good clinical judgement. We review and advocate long-term management of acute response using 6-mercaptopurine or azathioprine. The surgical experience and the postoperative complications of the ileal pouch anal anastomosis, which include acute pouchitis in 50-60%, chronic pouchitis in 5-10% and recent reports of dysplasia among patients with chronic pouchitis, must be considered before colectomy is advised. Over 80% of patients with acute severe colitis can be spared colectomy using our current arsenal of medical therapies.

Cost-effectiveness model for colon cancer screening

Background & Aims: The relative efficacy and effectiveness of different colon screening programs has not been assessed. The purpose of this analysis was to provide a model for comparing several colon screening programs and to determine the key variables that impact program effectiveness. Methods: Five screening programs were compared: annual fecal occult blood test (FOBT) alone, flexible sigmoidoscopy, flexible sigmoidoscopy and FOBT combined, one-time colonoscopy, and air-contrast barium enema. Key variables were adjusted for sensitivity analyses. Cost-effectiveness was defined as the cost per cancer death prevented. Results: FOBT alone prevents fewer cancer deaths than the other programs. The addition of flexible sigmoidoscopy to the FOBT increases the rate of cancer prevention. One-time colonoscopy has the greatest impact on colorectal cancer mortality, largely because of assumptions that cancer would be prevented in most patients who undergo polypectomy. FOBT alone is the most cost-effective of the programs, but the cost is sensitive to several key variables. Conclusions: The model shows key variables that impact the cost-effectiveness of colon screening programs. Compliance is an important determinant of effectiveness of all of the screening programs. Future study should be focused on methods of patient education that improve patient compliance with screening.