What is early-onset colon cancer?

Early-onset colon cancer, also called young-onset colon cancer, is defined as colon cancer diagnosed before age 50.

Colon cancer usually begins as small clumps of cells called polyps that form in the section of the large intestine called the colon. Rectal cancer starts as a growth of cells in the last several inches of the large intestine, called the rectum. Cancer inside the rectum and cancer inside the colon are often referred to together as colorectal cancer.