The American College of Physicians (ACP) issued updated guidance for colorectal cancer screening for asymptomatic, average-risk adults that suggests starting screening at age 50.

The guidance is based on a critical review of existing clinical guidelines and evidence reviews and modelling studies used to develop those guidelines. The guideline is published in Annals of Internal Medicine.

Colorectal cancer (CRC) is the fourth highest in incidence and second in mortality among cancers in the U.S.

The goal of this ACP guidance statement is to help guide physicians on when to start and stop screening, and on the selection of type and frequency of screening tests in asymptomatic, average-risk adults.

ACP’s guidance is for adults at average risk for CRC who do not have symptoms. It does not apply to adults with a family history of colorectal cancer, a long-standing history of inflammatory bowel disease, genetic syndromes such as familial cancerous polyps, a personal history of previous colorectal cancer or benign polyps, or other risk factors.

Physicians should perform an individualised risk assessment for CRC in all adults.

In this updated guidance, ACP suggests that clinicians:

• Start screening for colorectal cancer in asymptomatic average-risk adults at age 50 years.
• Consider not screening asymptomatic average-risk adults between the ages of 45 to 49. Clinicians should discuss the uncertainty around benefits and harms of screening in this population.
• Stop screening for colorectal cancer in asymptomatic average-risk adults older than 75 years or in asymptomatic average-risk adults with a life expectancy of 10 years or less.
• Select a screening test for colorectal cancer in consultation with their patient based on a discussion of benefits, harms, costs, availability, frequency, and patient values and preferences.
• Select among screening tests for colorectal cancer: a faecal immunochemical or high-sensitivity guaiac faecal occult blood test every 2 years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years plus a faecal immunochemical test every 2 years.
• Should not use stool DNA, computed tomography colonography, capsule endoscopy, urine, or serum screening tests for colorectal cancer.

The net benefit of colorectal cancer screening is much less favourable in average-risk adults between ages 45 to 49 years than 50 to 75 years.

Although there has been a small increase in CRC incidence among individuals aged 45 to 49 years, the incidence is much lower than in individuals aged 50 to 64 years and 65 to 74 years.

Harms associated with CRC screening include cardiovascular and gastrointestinal events (e.g., serious bleeding, perforation, myocardial infarction, angina), unnecessary follow-ups, and costs for findings deemed clinically unimportant. 

Source: ACP