• To incorporate updated evidence into clinical practice recommendations
• To summarize new developments in the field and suggest how they should change practice

Evidence-Based Medicine Guidelines collect, summarize, and update the core clinical knowledge essential in general practice. The guidelines also describe the scientific evidence underlying the given recommendations.

To implement an evidenced-based strategy for cancer screening in adults

• People in the United States (U.S.) at average risk for CRC (asymptomatic, age >50 years, no other risk factors)
• People in the U.S. at increased risk for CRC (history of adenomatous polyps or CRC; family history of colon cancer, an adenomatous polyp, familial adenomatous polyposis, or hereditary nonpolyposis CRC)

Note: People with symptoms or signs that suggest the presence of CRC or polyps fall outside the domain of screening and should be offered an appropriate diagnostic evaluation (see Table 2 in the original guideline document).

• Finland
• Asymptomatic persons with increased risk for colorectal cancer
• General population

• United States
• Adults, 18 years and older

Physicians

Health Care Providers
Physicians

Physicians

1. FOBT, guaiac-based and immunochemical technologies
2. Sigmoidoscopy
3. Combined FOBT and sigmoidoscopy
4. Colonoscopy
5. DCBE

1. FOBT, guaiac-based
2. Colonoscopy

1. FOBT
2. Flexible sigmoidoscopy
3. Colonoscopy

Screening options considered but not recommended:

1. Air or double-contrast barium enema
2. DRE
3. Stool deoxyribonucleic acid (DNA) test
4. Virtual colonoscopy

Note: This guideline also addresses interventions regarding breast cancer screening, prostate cancer screening and cervical cancer screening.

Men and women at average risk should be offered screening for colorectal cancer and adenomatous polyps beginning at age 50 years. They should be offered options for screening, with information about the advantages and disadvantages associated with each approach, and should be given an opportunity to apply their own preferences in selecting how they should be screened.

No recommendations offered.

Recommended methods include: FOBT, flexible sigmoidoscopy, or colonoscopy. (DRE is not effective in screening for colorectal cancer.)

Individualizing screening to offer the highest likelihood of compliance and the least intrusive option to the patient may be warranted. In addition to patient preference, other factors, such as age, comorbidities, and test availability may influence the choice of screening modality.

• Offer yearly screening with FOBT using a guaiac-based test with dietary restriction or an immunochemical test without dietary restriction.
• Two samples from each of 3 consecutive stools should be examined without rehydration.

The results of large trials involving screening for faecal occult blood indicate a reduction in mortality from colorectal cancer (Towler et al., 2002) [A], but such screening results in colonoscopy being performed on a large proportion of the screened population. The cost-effectiveness of screening is controversial. Only about 50% of those invited can be expected to attend screening (Vernon, 1997; DARE, 1999) [B].

Initiate: For average risk, asymptomatic patients, screening should begin at age 50.

Average risk. FOBT: annually [A]

Offer flexible sigmoidoscopy every 5 years.

No recommendations offered.

Initiate: For average risk, asymptomatic patients, screening should begin at age 50.

Average risk. Flexible sigmoidoscopy: every 5 years [A]

Offer screening with FOBT every year combined with flexible sigmoidoscopy every 5 years. When both tests are performed, the FOBT should be done first.

No recommendations offered.

Initiate: For average risk, asymptomatic patients, screening should begin at age 50.

Average risk: FOBT/flexible sigmoidoscopy: annually/every 5 years [B]

Screening with DRE was not considered.

Screening with DRE was not considered.

DRE is not effective in screening for colorectal cancer.

Offer DCBE every 5 years.

No recommendations offered.

Initiate: For average risk, asymptomatic patients, screening should begin at age 50.

Average risk: Air or double-contrast barium enema (acceptable modality but not recommended): every 5 years [B].

Offer colonoscopy every 10 years.

The use of colonoscopy for screening of asymptomatic individuals is indicated only in cases with marked familial susceptibility to cancer, or if an adenoma has earlier been removed endoscopically.

Initiate: For average risk, asymptomatic patients, screening should begin at age 50.

Average risk: Colonoscopy: every 10 years [B].

People with a first-degree relative (parent, sibling, or child) with colon cancer or adenomatous polyps diagnosed at age <60 years or 2 first-degree relatives diagnosed with colorectal cancer at any age should be advised to have screening colonoscopy starting at age 40 years or 10 years younger than the earliest diagnosis in their family, whichever comes first, and repeated every 5 years (see Table 3 in the original guideline document).

People with a first-degree relative with colon cancer or adenomatous polyp diagnosed at age >60 years or 2 second-degree relatives with colorectal cancer should be advised to be screened as average risk persons, but beginning at age 40 years.

People with 1 second-degree relative (grandparent, aunt, or uncle) or third-degree relative (great-grandparent or cousin) with colorectal cancer should be advised to be screened as average risk persons.

The use of colonoscopy for screening of asymptomatic individuals is indicated only in cases with marked familial susceptibility to cancer, or if an adenoma has earlier been removed endoscopically.

• Persons who have one second-degree (includes grandparents, aunts, and uncles) or any third-degree relative (includes great-grandparents and cousins) with colorectal cancer should be screened in the same way as average risk individuals.*
• Persons who have a first degree relative (includes parents, siblings, and children) affected with colorectal cancer or adenomatous polyp at age >60 years, or 2 second-degree relatives affected with colorectal cancer should be screened in the same way as average risk individuals, but starting at age 40 years.*
• Persons who have two or more first-degree relatives with colon cancer, or a single first-degree relative with colon cancer or adenomatous polyps diagnosed at an age <60 years should be screened with a colonoscopy every 5 years, beginning at age 40 years or 10 years younger than the earliest diagnosis in the family, whichever comes first.*

*From the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.

People who have a genetic diagnosis of familial adenomatous polyposis (FAP), or are at risk of having FAP but genetic testing has not been performed or is not feasible, should have annual sigmoidoscopy, beginning at age 10 to 12 years, to determine if they are expressing the genetic abnormality. Genetic testing should be considered in patients with FAP who have relatives at risk. Genetic counseling should guide genetic testing and considerations of colectomy.

The use of colonoscopy for screening of asymptomatic individuals is indicated only in cases with marked familial susceptibility to cancer or if an adenoma has earlier been removed endoscopically.

• Persons who have a first degree relative (includes parents, siblings, and children) affected with colon cancer or adenomatous polyps at age >60 years should be screened in the same way as average risk individuals, but starting at age 40 years.*
• Persons who have two or more first-degree relatives with colon cancer, or a single first-degree relative with colon cancer or adenomatous polyps diagnosed at an age <60 years should be screened with a colonoscopy every 5 years, beginning at age 40 years or 10 years younger than the earliest diagnosis in the family, whichever comes first*
• Persons who are gene carriers or at risk for familial adenomatous polyposis (includes the subcategories of familial adenomatous polyposis, Gardner syndrome, some Turcot syndrome families, and attenuated adenomatous polyposis coli [AAPC]) should be screened with a sigmoidoscopy annually, beginning at age 10 to 12 years. (For patients with APPC, colonoscopy should be used instead of sigmoidoscopy because of the preponderance of proximal colonic adenomas. Colonoscopy screening in AAPC should probably begin in the late teens or early 20s.)*

*From the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.

People with a genetic or clinical diagnosis of HNPCC or who are at increased risk for HNPCC should have colonoscopy every 1 to 2 years beginning at age 20 to 25 years, or 10 years earlier than the youngest age of colon cancer diagnosis in the family--whichever comes first. Genetic testing for HNPCC should be offered to first-degree relatives of persons with a known inherited mismatch repair (MMR) gene mutation. It should also be offered when the family mutation is not already known, but 1 of the first 3 of the modified Bethesda Criteria is met (see Table 5 in the original guideline document).

The use of colonoscopy for screening of asymptomatic individuals is indicated only in cases with marked familial susceptibility to cancer or if an adenoma has earlier been removed endoscopically.

Persons who are gene carriers or pancolitis at risk for HNPCC should be screened with a colonoscopy every 1 to 2 years, beginning at age 20 to 25 years or 10 years younger than the earliest case in the family, whichever comes first.*

*From the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.

Patients who have had 1 or more adenomatous polyps removed at colonoscopy should be managed according to the findings on that colonoscopy. Patients who have had numerous adenomas, a malignant adenoma (with invasive cancer), a large sessile adenoma, or an incomplete colonoscopy should have a short interval follow-up colonoscopy based on clinical judgment. Patients who have advanced or multiple adenomas (>3) should have their first follow-up colonoscopy in 3 years. Patients who have 1 or 2 small (<1 cm) tubular adenomas should have their first follow-up colonoscopy at 5 years. It is not unreasonable, given available evidence, to choose even longer intervals. However, the evidence is still evolving. Future evidence may clarify the intervals more precisely.

The timing of the subsequent colonoscopy should depend on the pathology and number of adenomas detected at follow-up colonoscopy. For example, if the first follow-up colonoscopy is normal or only 1 or 2 small (<1 cm) tubular adenomas are found, the next colonoscopy can be in 5 years.

• The use of colonoscopy for screening of asymptomatic individuals is indicated if an adenoma has earlier been removed endoscopically.
• Follow-up after the initial investigations is not indicated in persons with a single small tubular adenoma in the rectum, or in patients above 75 years of age.
• Individuals with a history of one large adenoma or several adenomas of any type should undergo screening colonoscopy at 3- to 5-year intervals.

Persons who have a history of adenomatous polyps, for example:

• 1 or 2 small (<1 cm) tubular adenomas
• Advanced or multiple adenomas (>3)

Manage according to the findings and clinical judgment, for example:

• First follow-up colonoscopy at 5 years
• First follow-up colonoscopy in 3 years.

Timing of subsequent colonoscopy depends on findings at follow-up.*

*From the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.

Patients with a colon cancer that has been resected with curative intent should have a colonoscopy around the time of initial diagnosis to rule out synchronous neoplasms. If the colon is obstructed preoperatively, colonoscopy can be performed approximately 6 months after surgery. If this or a complete preoperative examination is normal, subsequent colonoscopy should be offered after 3 years, and then, if normal, every 5 years.

No recommendations offered.

History of CRC: After colonoscopy to rule out synchronous neoplasms and resection with curative intent, first follow-up colonoscopy after 3 years, and then, if normal, every 5 years.

*From the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.

In patients with long-standing, extensive inflammatory bowel disease, surveillance colonoscopy with systematic biopsies should be considered. This applies to both ulcerative colitis and Crohn's colitis because the cancer risk is similar in both diseases.

No recommendations offered.

Inflammatory bowel disease (ulcerative colitis, Crohn's colitis): In patients with long-standing, extensive inflammatory bowel disease (ulcerative colitis, Crohn's colitis), surveillance colonoscopy with systematic biopsies should be considered.*

*From the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.

• Increased rates of appropriate and timely colorectal cancer screening based on patient and physician collaboration
• Improved physician and patient understanding of the rationale and evidence supporting colorectal cancer screening options (refer to the rationale section in the original guideline document for the relative effectiveness of each screening test)
• Reduced morbidity and mortality due to colorectal cancer
• Reduced health care costs

Screening may help detect colorectal cancer and reduce the incidence of or mortality from colorectal cancer.

Early detection and treatment may avert future cancer-related illness.

• Currently available tests for fecal occult blood fail to detect many polyps and some cancers. Also, most people who test positive will not have colorectal neoplasia (have a false positive test result) and thus will undergo the discomfort, cost, and risk of colonoscopy without benefit.
• Colonoscopy involves greater cost, risk, and inconvenience to the patient than other screening tests, and not all examinations visualize the entire colon.
• Genetic testing can have psychological effects and subject persons with positive tests to the risks of discrimination. Therefore, it should only be performed after genetic counseling of patients and parents of children.

Harmful effects of screening include:

• The physical complications of colonoscopy (perforation or haemorrhage)
• Disruption to lifestyle
• Stress and discomfort of testing and investigations
• The anxiety caused by false positive screening tests
• False negative tests. Because the sensitivity and specificity of faecal occult blood are rather poor, a negative result does not exclude colorectal cancer in a symptomatic patient.

No harmful effects discussed

Levels of Evidence

1. Strong research-based evidence. Several relevant, high-quality scientific studies with homogeneous results.
2. Moderate research-based evidence. At least one relevant, high-quality study or multiple adequate studies.
3. Limited research-based evidence. At least one adequate scientific study.
4. No scientific evidence. Expert panel evaluation of other information.

References Supporting the Recommendations

• The database of abstracts of reviews of effectiveness (University of York), DARE-971223. In: Cochrane Library [database online]. Issue 4. Oxford: Update Software; 1999
• Towler BP, Irwig L, Glasziou P, Weller D, Kewenter J. Screening for colorectal cancer using the faecal occult blood test, Hemoccult [CD001216]. In: Cochrane Database of Systematic Reviews, Cochrane Library [database online]. Issue 2. Oxford: Update Software; 2002
• Vernon SW. Participation in colorectal cancer screening: a review. J Natl Cancer Inst 1997 Oct 1;89(19):1406-22. [214 references]

Levels of evidence reflect the best available literature in support of an intervention or test:

1. Randomized controlled trials
2. Controlled trials, no randomization
3. Observational trials
4. Opinion of expert panel

References Supporting the Recommendations

American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, American College of Physicians, American College of Gastroenterology (AGA/ASGE/ACP/ACG). Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003 Feb;124(2):544-60.