The American College of Physicians (ACP) has published its recommendations for the testing of colorectal cancer among average-risk adults.
“Colorectal cancer (CRC) is the second leading cause of cancer-related death in men and women in the United States. The goal of screening is to reduce overall and cancer-specific morbidity and mortality using strategies that have acceptable harms, burden, and costs,” wrote the authors of the guidelines, which appeared in the Annals of Internal Medicine.
The guidelines are summarized in three statements.
The first guideline statement recommends that all average-risk adults between ages 50 and 75 years undergo colorectal cancer screening.
Regular colorectal cancer screening is associated with reduced risk of colorectal cancer mortality. The median age at colorectal cancer diagnosis is 67 years, and patients aged between 65 to 75 years seem to benefit the most from regular screening. However, starting screening at age 50 also has proven benefits.
The second guideline statement recommends that clinician first discuss with the patient the benefits, harms, costs, availability, frequency, and patient preferences associated with screening. Testing recommendations include two-year fecal immunochemical testing or high-sensitivity guaiac-based fecal occult blood testing, 10-year colonoscopy, or 10-year flexible sigmoidoscopy plus two-year fecal immunochemical testing.
All screening options come with their own benefits and risks.
“Because many eligible patients have never been screened and some may not adhere to recommendations about subsequent screening or follow-up of positive findings on screening tests (such as colonoscopy after a positive result on a stool-based screening test), patient informed decision making and adherence are important factors in selection of a [colorectal cancer] screening test. Discussion should include such topics as suggested frequency, bowel preparation, anesthesia, transportation to and from the examination site, time commitments, and the necessary steps if a test result is positive,” the researchers clarified.
The third guideline statement recommends that screening be discontinued in average-risk adults aged older than 75 years and in adults whose life expectancy is 10 years or less.
The risks of harm associated with screening increase with age, the researchers explained:
“Accurate prediction of individual life expectancy is difficult. However, among 75-year-old men and women in the United States, average life expectancy is 9.9 and 12 years, respectively. Among men and women aged 70 years with serious comorbid conditions, life expectancy is 8.9 and 10.8 years, respectively. Therefore, most persons aged 75 years or older, as well as most adults who are younger than 75 years but have serious comorbid conditions (such as chronic renal failure), are unlikely to benefit from screening but would undergo unnecessary, burdensome, potentially harmful, and costly screening tests.”
These guidelines are applicable to average-risk patients and do not apply to patients with a family history of colorectal cancer, a long-standing history of inflammatory bowel disease, a genetic syndrome like familial adenomatous polyposis, or a personal history of colorectal cancer or adenomatous polyps—these patients, according to the authors, have an above-average risk.