What are the current guidelines for colonoscopy screening for Colorectal Cancer (CRC)?

From the Guidelines

Current colonoscopy screening guidelines recommend that average-risk individuals begin screening at age 45 and continue until age 75, with screening occurring every 10 years if results are normal, as supported by the most recent and highest quality study 1. The guidelines for colonoscopy screening have been established to detect colorectal cancer at early, more treatable stages and to identify and remove precancerous polyps before they develop into cancer.

• The American Cancer Society recommends that average-risk individuals begin screening at age 45, while the U.S. Multi-Society Task Force on Colorectal Cancer recommends screening starting at age 50 1.
• Individuals with a family history of colorectal cancer or advanced polyps in a first-degree relative should begin screening earlier, typically at age 40 or 10 years before the youngest case in the family, as suggested by the U.S. Preventive Services Task Force 1.
• The preparation for colonoscopy typically involves a clear liquid diet the day before the procedure and consuming a bowel-cleansing solution such as polyethylene glycol (GoLYTELY, MoviPrep), sodium picosulfate, or magnesium citrate, with split-dose preparation improving bowel cleanliness 1.
• Patients should arrange for someone to drive them home after the procedure due to sedation effects, and surveillance intervals may be shortened to 3-5 years based on findings for those at higher risk due to personal history of polyps or colorectal cancer, as recommended by the National Comprehensive Cancer Network 1. The guidelines aim to reduce colorectal cancer mortality by detecting cancer at an early, curable stage and may decrease colorectal cancer incidence by detecting and removing adenomatous polyps, with the progression from polyp to cancer typically taking 7-10 years 1.

From the Research

Current Guidelines for Colonoscopy Screening

• The current guidelines for colonoscopy screening recommend that average-risk individuals should undergo screening between 45 and 75 years of age 2, 3, 4, 5.
• For high-risk individuals, such as those with a positive family history of colorectal cancer or advanced colorectal polyp, screening should begin at age 40 2.
• The recommended screening modalities include colonoscopy, fecal immunochemical test (FIT), and computed tomographic (CT) colonography (virtual colonoscopy) 2, 3, 4, 5.
• The screening intervals suggested are:
  • Colonoscopy every 10 years for average-risk individuals and every 5-10 years for high-risk individuals 2.
  • FIT annually for average-risk individuals and every 1-2 years for high-risk individuals 2.
  • CT colonography every five years for all individuals 2.

Screening Age and Recommendations

• The U.S. Multi-Society Task Force on Colorectal Cancer recommends that average-risk individuals should start screening at age 45 3.
• The decision to start or continue screening for individuals ages 76 to 85 should be individualized and based on prior screening history, life expectancy, CRC risk, and personal preference 3.
• Screening is not recommended after age 85 3.

Screening Methods and Effectiveness

• Fecal occult blood tests, including Guaiac test and immunochemical test, are also used for screening, but their validity and effectiveness vary 6.
• The sensitivity and specificity of these tests differ, with immunochemical test showing better results for the diagnosis of colorectal cancer compared to Guaiac test 6.
• Colonoscopy is considered the "gold standard" for the diagnosis of CRC and adenomatous polyps 6.