Colorectal screening should start at the age of 50

Colorectal adenomas, the precursor polyps in virtually all colorectal cancers, occur infrequently in younger adults, but the rate sharply increases after age 50.

Francis Giardiello, of The John Hopkins University and colleagues found that the prevalence of colorectal polyps in younger adults increased from 1.72 percent to 3.59 percent from age 30 to 50. This rate sharply increased after age 50 with the prevalence of polyps ranging from 10.1 to 12.06 percent in the sixth and ninth decade, respectively. The study results quantified the number of adenomas typically found in people under the age of 50. It is important to note that those with two or more adenomas under 50 years of age represent unusual individuals who might merit closer colonoscopic surveillance for subsequent adenoma development.

In younger adults, adenomas were more prevalent in Caucasians compared to African Americans; however, in older adults, the reverse was true. Regardless of age, adenomas were more prevalent in men than women.

Colonoscopy, which provides the most comprehensive view of the colon, is the definitive test for colorectal cancer screening. Colonoscopies allow gastroenterologists to view the entire colon and rectum for polyps or cancer and during the same exam remove pre-cancerous polyps. It is the test most gastroenterologists recommend as the single best screening exam for colorectal cancer. It is the only method that combines both screening and prevention (by removal of pre-cancerous polyps).