external beam radiothearpy
article written by article by Dr Michael Rampaul
Radiation therapy uses high-energy rays to kill prostate cancer cells,
shrink tumors or prevent cancer cells from dividing and spreading. Because
the rays cannot be directed perfectly, they may damage both cancer cells
and healthy cells nearby. If the dose of radiation is small and spread
out over time, however, the healthy cells are able to recover and survive,
and the cancer cells eventually die.
Radiation therapy is usually used when prostate cancer has spread beyond
the prostate. It can help prevent the cancer from spreading further.
Like surgery, radiation therapy works best when the cancer is located
in a small area. In early stages of prostate cancer, radiation therapy
may cure the disease. Radiation therapy may be used alone or in
combination with hormone therapy when cancer cells have spread beyond
the prostate to the pelvic area and for pain relief in prostate cancer
that is no longer responding to hormone therapy and has spread to the bones.
There are two ways in which the high energy rays can be delivered.
In external beam radiation therapy, the rays are delivered by a machine,
and the radiation is given in brief sessions, usually one session each
weekday for several weeks.
In internal radiation therapy (brachytherapy), the rays come from tiny
radioactive seeds inserted directly into the prostate.