Radiotherapy is a form of cancer treatment that uses x-rays to
kill cancer cells. The radiation in the x-rays is concentrated
specifically on the cancer cells. Radiotherapy might be used
alone or in combination with other cancer treatments like
chemotherapy or surgery.  The combinations of treatments, and
how long radiotherapy is used, depend on the type of cancer
being treated and the area of the body where the cancer resides.
Like chemotherapy, radiotherapy might be used before surgery to
shrink the size of a tumor, or after surgery to kill any
remaining cancer cells. Radiotherapy might also be used to help
lessen some of the side effects of chemotherapy.  External vs.
internal radiotherapy  There are a lot of specialists that work
together to administer radiotherapy to your child. Many people
understand that radiotherapy can be given externally, as x-rays,
but it can also be administered internally.  When internal
radiotherapy is used, hollow tubes or rods are placed in your
child's body, close to the tumo