The colon is the last part of the digestive system in most vertebrates. It extracts water and salt from solid wastes before they are eliminated from the body and is the site Unlike the small intestine; the colon does not play a major role in the absorption of foods and nutrients. However, the colon does absorb water, sodium and some fat soluble vitamins.
Colon, or colorectal, cancer is cancer that starts in the large intestine (colon) or the rectum (end of the colon).
- Diarrhea or Constipation
- Changes in stool consistency
- Narrow stools
- Rectal bleeding or blood in the stool
- Pain, cramps, or gas in the abdomen
- Pain during bowel movements
- Continual urges to defecate
- Weakness or fatigue
- Unexplained weight loss
- Irritable bowel syndrome (IBS)
- Iron deficiency (anemia)
Surgery to remove part of or the entire colon is called colostomy. During colectomy, a surgeon will remove the part of the colon containing cancer as well as the marginal area close to cancer. Also, nearby lymph nodes are also usually removed. Depending on the extent of the colectomy, the healthy portion of the colon will either be reattached to the rectum or attached to an opening in the wall of the abdomen called a stoma. This latter option is called a colostomy, and waste will exit the body through the stoma into a colostomy bag instead of exiting through the rectum.
Chemotherapy utilizes chemicals that interfere with the cell division process – damaging proteins or DNA – so that cancer cells will commit suicide. These treatments target any rapidly dividing cells (not necessarily just cancer cells), but normal cells usually can recover from any chemical-induced damage while cancer cells cannot. Chemotherapy is used to treat cancer that has spread or metastasized because the medicines travel throughout the entire body. Treatment occurs in cycles, so the body has time to heal between doses. However, there are still common side effects such as hair loss, nausea, fatigue, and vomiting. Combination therapies often include multiple types of chemotherapy or chemotherapy combined with other treatment options.
Radiation treatment, also known as radiotherapy, destroys cancer by focusing high-energy rays on the cancer cells. It causes damage to the molecules that make up the cancer cells and leads them to commit suicide. Radiotherapy utilizes high-energy gamma-rays that are emitted from metals such as radium or high-energy x-rays that are created on a particular machine. Radiotherapy can be used as a standalone treatment to shrink a tumor or destroy cancer cells, and it is also used in combination with other cancer treatments.