Radiation therapy uses a special type of high-energy beam to damage cancer cells. (Other types include light and x-rays.) These high-energy beams, invisible to the human eye, damage a cell’s DNA which is the material that cells use to divide.
HOW DOES RADIATION WORK?
Over time, radiation damages cells that are in the path of its beam—normal cells as well as cancer cells. However, radiation affects cancer cells more than normal cells. Cancer cells are busy growing and multiplying — two activities that can be slowed or stopped by radiation damage. And because cancer cells are less organized than healthy cells, it’s harder for them to repair the damage done by radiation. Thus, cancer cells are more easily destroyed by radiation, while healthy, normal cells are better able to repair themselves and survive the treatment.
There are two different ways to deliver radiation to the tissues which require treatment:
A unit called a linear accelerator that delivers radiation from outside the body
Pellets or seeds of material that give off radiation beams from inside the body tissues to be treated might include the breast area, lymph nodes, or another part of the body.
WHAT ARE THE BENEFITS OF RADIATION?
Radiation is an important and often necessary form of anti-cancer therapy because it is able to reduce the risk of recurrence after surgery. Although it’s quite possible that your surgeon removed all of the cancer, breast cancer surgery cannot guarantee that every last cancer cell has been eradicated from your body. This is because individual cancer cells are too small to be felt or seen during surgery or detected by testing. Any cells that remain after surgery can grow and eventually form a new lump or show up as an abnormality on a test such as a mammogram.