What are the recommended colon cancer screening guidelines for individuals with a family history of colon cancer?

From the Guidelines

Individuals with a family history of colon cancer should begin screening earlier than the general population, typically at age 40 or 10 years before the youngest diagnosed first-degree relative, whichever comes first, as recommended by the most recent guidelines 1. The preferred screening method is colonoscopy, which should be repeated every 5 years for those with a family history, rather than the standard 10-year interval recommended for average-risk individuals. Some key points to consider when screening for colon cancer with a family history include:

• Having a first-degree relative with colorectal cancer approximately doubles your lifetime risk 1.
• Early and more frequent screening allows for detection and removal of precancerous polyps before they develop into cancer, significantly reducing your risk of developing advanced colorectal cancer.
• For those with known genetic syndromes like Lynch syndrome or Familial Adenomatous Polyposis (FAP), screening recommendations are more aggressive, potentially beginning in the late teens or early twenties with annual colonoscopies 1.
• If you have multiple affected relatives or relatives diagnosed before age 60, screening may need to start even earlier and occur more frequently 1. It's essential to note that the guidelines may vary depending on the specific family history and other risk factors, and it's crucial to consult with a healthcare professional to determine the best screening plan. The most recent study 1 provides the most up-to-date recommendations for colon cancer screening in individuals with a family history, and its findings should be prioritized when making screening decisions.

From the Research

Colon Cancer Screening Guidelines for Individuals with a Family History

The recommended colon cancer screening guidelines for individuals with a family history of colon cancer vary depending on the number of affected first-degree relatives and their age at diagnosis.

• Individuals with one first-degree relative diagnosed with colon cancer after age 50 should undergo 6 colonoscopies every 5 years starting at age 50 2.
• Those with one first-degree relative diagnosed before age 50 should have 10 colonoscopies every 4 years 2.
• Individuals with two or more first-degree relatives diagnosed after age 50 should undergo 13 colonoscopies every 3 years 2.
• Those with two or more first-degree relatives, at least one of whom was diagnosed before age 50, should have 15 colonoscopies every 3 years 2.

Initiating Screening at an Earlier Age

Initiating screening at an earlier age based on cancer family history is one of the primary recommended strategies for the prevention and detection of early-onset colorectal cancer (EOCRC) 3.

• Family history-based early screening criteria were met by approximately 25% of cases and 10% of controls, with a sensitivity of 25% and a specificity of 90% for identifying EOCRC cases aged 40 to 49 years 3.
• Nearly all cases who met these criteria could have had CRC diagnosed earlier (or possibly even prevented) if earlier screening had been implemented as per family history-based guidelines 3.

Screening Recommendations for First-Degree Relatives

Consensus guidelines recommend first-degree relatives of individuals diagnosed with an adenoma before age 60 should be screened every 5 years with colonoscopy starting at age 40 4.

• However, the US Preventive Services Task Force does not recommend more aggressive screening of first-degree relatives of individuals with an adenoma due to uncertainties in the risk of CRC 4.
• First-degree relatives of individuals with adenomas should be screened as average-risk persons until more compelling data are available to justify more aggressive screening 4.

General Screening Recommendations for Individuals at Increased Risk

Individuals at increased risk of developing colorectal cancer, including those with a personal or family history of advanced adenomas or colorectal cancer, should undergo more frequent or earlier testing than individuals at average risk 5.

• Those with a first-degree relative with colorectal cancer or advanced adenoma diagnosed before 60 years of age or two first-degree relatives diagnosed at any age should start screening colonoscopy at 40 years of age or 10 years younger than the earliest diagnosis in their family, whichever comes first 5.

Adherence to National Guidelines

Currently, there are no data on adherence to guidelines for colorectal cancer screening in patients with a family history 6.

• A retrospective study found that only 40.3% of patients with a family history of CRC were screened appropriately, with 58.9% having late initiation of screening and 0.8% having premature initiation 6.
• Further education of patients and providers on screening recommendations may be helpful to improve adherence to national guidelines 6.