A patient may be given chemotherapy through a tube that will be left in the vein while a small pump gives the patient constant treatment over a period of weeks. Chemotherapy is called a systemic treatment because the drug enters the bloodstream, travels through the body, and can kill cancer cells outside the colon. If the cancer has spread to the liver, the patient may be given chemotherapy directly into the artery going to the liver. If the doctor removes all the cancer that can be seen at the time of the operation, the patient may be given chemotherapy after surgery to kill any cancer cells that are left. Chemotherapy given after an operation to a person who has no cancer cells that can be seen is called adjuvant chemotherapy.
Biological treatment tries to get the body to fight cancer.
It uses materials made by the body or made in a laboratory to boost, direct, or restore the body's natural defenses against disease.