General Information About Colorectal Cancer
Colorectal cancer is a disease in which malignant (cancer) cells form in the tissues of the colon or the rectum.
The colon is part 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).
Anatomy of the lower digestive system, showing the colon and other organs.
Cancer that begins in the colon is called colon cancer, and cancer that begins in the rectum is called rectal cancer. Cancer that affects either of these organs may also be called colorectal cancer.
See the following PDQ summaries for more information about colorectal cancer:
- Colorectal Cancer Screening
- Colon Cancer Treatment
- Rectal Cancer Treatment
- Genetics of Colorectal Cancer
Colorectal cancer is the second leading cause of death from cancer in the United States.
The number of new colorectal cancer cases and the number of deaths from colorectal cancer are both decreasing a little bit each year. However, in adults younger than 50 years, the number of new colorectal cancer cases has slowly increased since 1998.
Finding and treating colorectal cancer early may prevent death from colorectal cancer. Screening tests may be used to help find colorectal cancer.