Colon cancer is sometimes called colorectal cancer, which is a term that combines colon cancer and rectal cancer, which begins in the rectum.
Most often, colorectal cancer starts in gland cells that line the wall of the colon or rectum. These gland cells make mucus that helps stool move through the colon and rectum.
A persistent change in your bowel habits, including diarrhea or constipation or a change in the consistency of your stool Many people with colon cancer experience no symptoms in the early stages of the disease. When symptoms appear, they’ll likely vary, depending on the cancer’s size and location in your large intestine.