Radiation Therapy and Cancer Treatment
Radiation therapy is also
called radiotherapy or therapeutic radiology. Using it to treat cancer is called radiation
Radiation therapy uses high-energy
X-rays, gamma rays, or charged particles to kill cancer cells. Like surgery, it can be used
in many ways depending on the type of cancer and where it is in the body. Certain levels of
radiation kill cancer cells or keep them from growing or reproducing.
This treatment may be used to cure
cancer, help control the disease, or help relieve symptoms it's causing.
Most radiation treatments come from a
large machine that doesn't touch you and won't make you radioactive. Less often, a source
of radiation may be put right into your body. Talk with your healthcare provider about any
safety measures you need to take when getting radiation therapy.
What are the different types of radiation therapy?
Radiation therapy is given through
different ways. The way you get it depends on the type of cancer, where it is in your
body, your overall health, and your preferences. Radiation therapy is often used with
other treatments, like chemotherapy or surgery. Different types of radiation therapy
External radiation (external beam therapy). A large
machine points the radiation beams through your skin and right at the tumor. The
beams are often aimed at the tumor from many different angles. A radiation
therapist controls the machine. Since radiation can also affect nearby normal
cells, special shields may be made to protect the tissue near the treatment area.
Most of the time, treatment is done 5 days a week for many weeks. Radiation
treatments don't hurt. They usually last only a few minutes.
Internal radiation (brachytherapy, implant radiation, or
systemic radiation). A high dose of radiation is given inside the body.
It's put as close to the cancer as possible. The radiation source may be
swallowed, injected into your blood, implanted right into the tumor, or put next
to the tumor through a body opening (such as the rectum). Some of the radioactive
implants are called seeds or capsules. Internal radiation allows you to get a
higher dose of radiation over a shorter time when compared with external
radiation. Some sources of internal radiation stay in the body for a short time.
Others stay in the body forever. But they lose their radiation energy over
In some cases, both internal and
external radiation therapies are used.
Before you get radiation therapy
Radiation should be aimed as
precisely at the tumor as possible. This is important for treating the tumor. It’s also
important to help keep nearby normal tissues from getting too much radiation. That could
lead to side effects. Each hospital may have certain protocols. But radiation therapy
usually starts with these procedures:
You will first have a physical exam and a review of your medical
history. Your treatment team then maps out the position you'll be in for each
treatment and the exact place on your body where the radiation will be given. This is
called the treatment field or port. You may also have imaging studies, such as CT
scans, MRI scans, or PET scans. These may be used to help see exactly where the tumor
is. This process takes a while, often a couple hours.
Sometimes, the skin over the part of your body to be treated will
be marked with tiny dot tattoos. This is done to make sure radiation is given to the
exact same place each time. The treatment team may also make casts, masks, molds,
headrests, or other devices. These help put you in and keep you in the same position
for each treatment.
Once the simulation process is done, a healthcare provider called a radiation
oncologist will work with a team of experts to create your treatment plan. The plan
The type of radiation to use
How it will be given
The amount (dose) of radiation that's needed
The number of treatments you'll get