The colon and rectum are parts of the body's digestive system. The digestive system removes and
processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and
water) from foods and helps pass waste material out of the body. The digestive
system is made up of the mouth, throat, esophagus,
stomach, and the
small and large
intestines. The first 6 feet of the
large intestine are called the large bowel or colon. The last 6 inches are the
rectum and the anal canal. The anal
canal ends at the anus (the opening
of the large intestine to the outside of the body).
Cancer that begins in the colon is called colon cancer, and cancer that begins in the rectum is called rectal cancer. Cancer that begins in either of these organs may also be called colorectal cancer.
See the following PDQ summaries for more information about colorectal cancer:
The number of new colorectal cancer cases and the number of deaths from colorectal cancer are decreasing a little bit each year. But in adults younger than 50 years, there has been a small increase in the number of new cases each year since 1998. Colorectal cancer is found more often in men than in women.
Anything that increases a person's chance of getting a disease is called a risk factor. Risk factors for colorectal cancer include the following: