What are the NCCN colonoscopy screening and surveillance guidelines for average‑risk adults, individuals with a family history of colorectal cancer, prior adenomas or serrated polyps, inflammatory bowel disease, or hereditary colorectal cancer syndromes?

NCCN Colonoscopy Screening and Surveillance Guidelines

Average-Risk Adults

For average-risk adults, NCCN recommends beginning colorectal cancer screening at age 45 years and continuing through age 75 years, with colonoscopy every 10 years as a primary screening option. 1

Screening Initiation and Age Range

• Begin screening at age 45 years for adults with no personal history of adenoma, sessile serrated lesions (SSLs), CRC, inflammatory bowel disease, high-risk genetic syndromes, cystic fibrosis, or childhood cancer, and no family history of CRC or advanced adenomas 1
• Continue screening through age 75 years as the standard recommendation 1
• For ages 76-85 years, screening decisions should be individualized based on prior screening history, comorbidity status, and estimated life expectancy, with those who have never been screened most likely to benefit 1
• Do not screen adults older than 85 years 1

Screening Modality Options for Average-Risk Adults

NCCN provides multiple acceptable screening options 1:

Colonoscopy:

• Every 10 years 1
• If incomplete or preparation is suboptimal, consider alternative screening modality or repeat colonoscopy within 1 year 1

Stool-Based Tests:

• High-sensitivity guaiac-based or immunochemical-based testing (FIT) annually, with FIT showing superior sensitivity to guaiac-based tests 1
• FIT-DNA testing every 3 years 1

Structural Tests:

• Flexible sigmoidoscopy every 5-10 years 1
• CT colonography (CTC) every 5 years 1

Important Caveats for Average-Risk Screening

• Any abnormal result from stool-based screening tests is an indication for colonoscopy 1
• A blood test detecting circulating methylated SEPT9 DNA is FDA-approved but has inferior ability to detect CRC and advanced adenoma compared to other recommended modalities 1
• NCCN does not currently endorse screening with barium enema 1

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Increased-Risk Adults: Family History of Colorectal Cancer

First-Degree Relative with CRC Diagnosed <60 Years

• Begin colonoscopy at age 40 years OR 10 years before the age at diagnosis of the affected relative, whichever comes first 2, 3
• Repeat colonoscopy every 5 years 2, 3, 4
• This recommendation applies because the risk is 3-4 times higher than average-risk populations 2, 4

Two or More First-Degree Relatives with CRC at Any Age

• Begin colonoscopy at age 40 years OR 10 years before the youngest affected relative's diagnosis, whichever is earlier 2, 3
• Repeat colonoscopy every 5 years 2, 3

First-Degree Relative with CRC Diagnosed ≥60 Years

• Begin screening at age 40 years using average-risk screening options (colonoscopy every 10 years or annual FIT) 2, 3
• The risk is only modestly elevated (1.8-1.9 fold) in this scenario 3

First-Degree Relative with Advanced Adenoma Diagnosed <60 Years

• Follow the same protocol as CRC diagnosed <60 years: colonoscopy at age 40 years or 10 years before diagnosis, repeated every 5 years 2, 3

Second- or Third-Degree Relatives with CRC

• Begin colonoscopy at age 45 years and repeat every 10 years 2, 3

Critical Verification Required

• Always verify the exact age at diagnosis of affected relatives, as the 60-year cutoff determines whether 5-year or 10-year intervals are recommended 2, 3
• Family history information is often incomplete or inaccurate—confirm the diagnosis and relationship whenever possible 3, 5

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Post-Polypectomy Surveillance

After Removal of Adenomatous Polyps

For 1-2 Small (<1 cm) Tubular Adenomas with Low-Grade Dysplasia:

• Next colonoscopy in 5-10 years, with timing based on family history and other clinical factors 3

For Advanced Adenomas (≥1 cm, villous features, high-grade dysplasia) OR 3-10 Total Adenomas:

• Next colonoscopy in 3 years 3
• If the 3-year surveillance is clear or shows only 1-2 small tubular adenomas, the interval can be extended to 5 years for subsequent colonoscopies 3
• If the 3-year surveillance shows 3+ adenomas or any advanced features, continue 3-year intervals 3

For Piecemeal Removal:

• A 2-6 month follow-up colonoscopy is necessary to verify complete removal before establishing the surveillance schedule 3

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Inflammatory Bowel Disease

While NCCN guidelines focus primarily on sporadic CRC screening, patients with long-standing inflammatory bowel disease require specialized surveillance protocols beyond average-risk screening 1. These patients are considered above-average risk and require colonoscopy-based surveillance rather than stool-based screening 1.

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Hereditary Colorectal Cancer Syndromes

Classical Familial Adenomatous Polyposis (FAP)

When Mutation is Known in Family:

• APC gene testing for at-risk first-degree relatives 1
• If APC gene positive: flexible sigmoidoscopy or colonoscopy every 12 months beginning at age 10-15 years 1
• If APC gene negative: follow average-risk screening 1

When Mutation is Unknown in Family:

• APC gene testing of affected family member first 1
• If affected family member unavailable: flexible sigmoidoscopy or colonoscopy beginning at age 10-15 years with the following schedule 1:
  • Every 12 months until age 24 years
  • Every 2 years until age 34 years
  • Every 3 years until age 44 years
  • Then every 3-5 years thereafter
• Consider substituting colonoscopy every 5 years beginning at age 20 years for the possibility of attenuated FAP 1
• Consider MYH testing when polyposis is present with negative APC testing 1

Lynch Syndrome Suspicion

• Multiple relatives with polyps or cancer, especially if diagnosed before age 50, should prompt genetic counseling 3
• If Lynch syndrome is confirmed: colonoscopy every 1-2 years starting 10 years before the youngest affected relative's diagnosis age 3

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Common Pitfalls to Avoid

• Do not wait until age 50 to begin screening if any first-degree relative has CRC—screening must start at age 40 at the latest 3, 5
• Do not use 10-year intervals for colonoscopy if a first-degree relative was diagnosed before age 60 or if there are two or more affected first-degree relatives—these situations require 5-year intervals 3
• Do not assume all family history is equal—second-degree relatives do not warrant the same intensive screening as first-degree relatives 3
• Single-panel guaiac FOBT performed in the office during digital rectal examination is NOT acceptable for screening due to very low sensitivity 5
• All stool-based tests should be done on voided stool samples, not on samples obtained by digital rectal examination 1

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Quality Indicators for Colonoscopy

Colonoscopy quality is critical for effective screening 1, 5:

• Cecal intubation rate should be achieved 1, 5
• Adenoma detection rate ≥25% in men 5
• Withdrawal time ≥6 minutes 5
• Adequate bowel preparation is essential and should be discussed with patients 1