When Is Radiation Therapy Used?

Both internal and external radiation therapy can be used as:

• Curative therapy, where the goal is to eliminate all signs of cancer.

• Palliative therapy, which relieves symptoms, including pain. Lower doses are given over a shorter period of time.

• Adjuvant Therapy, which means using it in combination with other in combination with surgery, chemotherapy (use of anti-cancer drugs that destroy cancer cells), hormone therapy, or other treatments.

Adjuvant radiation therapy can be used:

• Before surgery to shrink a tumor, called neoadjuvant therapy.

• With or after chemotherapy, which can make tumors more receptive to radiation therapy.

• After surgery to make sure all cancer cells are destroyed (adjuvant).

Total Body Irradiation

This form of radiation therapy is used in conjunction with a bone marrow transplant. One large dose (or six to eight smaller doses) is given to the entire body to destroy cancer cells.

One major disadvantage is that healthy bone marrow is also destroyed. But then new bone marrow cells, taken from either a donor or the patient before irradiation, are given back to the patient after the high-dose radiation. These new cells replace the damaged bone marrow cells and rebuild a person's immune system (the system in the body that fights infection and disease).