The incidence of colorectal cancer fell by more than one-third in the United States between 1985 and 2005—mostly because more people were screened for the disease.

The incidence of colorectal cancer fell by more than one-third in the United States between 1985 and 2005—mostly because more people were screened for the disease.

Yet colorectal cancer remains the second-leading cause of cancer deaths, claiming the lives of nearly 50,000 Americans each year. The vast majority of these cases could be averted or caught in an early, curable stage if people simply started getting regular screenings when they hit the age of 50 (or possibly earlier if a family member has had the disease). Indeed, about 45% of Americans 50 or older have never been screened for colorectal cancer.

Many experts consider a colonoscopy to be the most sensitive and specific cancer-screening tool available. In the procedure, doctors guide an endoscope (a long, flexible tube equipped with a tiny camera) through the entire colon. This enables them to detect and remove polyps and lesions before they turn cancerous.