Cancer Home > Colorectal Cancer Treatment
Chemotherapy uses anticancer drugs to kill cancer cells. It is called systemic therapy because it enters the bloodstream and can affect cancer cells throughout the body.
The patient may have chemotherapy alone or combined with surgery, radiation therapy, or both as part of colorectal cancer treatment. Chemotherapy given before surgery is called neoadjuvant therapy. Chemotherapy administered prior to surgery may shrink a large tumor.
Chemotherapy after surgery is called adjuvant therapy. Adjuvant therapy is used to destroy any remaining cancer cells and prevent the cancer from coming back in the colon, rectum, or elsewhere.
Chemotherapy is also used to treat people with advanced cancer.
Anticancer drugs are usually given through a vein, but some also may be given by mouth. The patient may be treated in an outpatient section of the hospital, at the doctor's office, or at home. Rarely, a hospital stay may be needed.
Radiation therapy (also called radiotherapy) is a form of local therapy. It uses high-energy rays to kill cancer cells. It affects cancer cells only in the treated area.
Doctors use two types of radiation therapy for treating colorectal cancer. Sometimes people receive both types:
- External radiation: The radiation comes from a machine. Most patients go to the hospital or clinic for their treatment, generally five days a week for several weeks. In some cases, external radiation is given during surgery.
- Internal radiation (implant radiation): The radiation comes from radioactive material placed in thin tubes put directly into or near the tumor. The patient stays in the hospital and the implants generally remain in place for several days. They are usually removed before the patient goes home.