Radiation Therapy: Purpose, Procedure, Side Effects, and More
Key takeaways
Radiation therapy uses high-energy waves to damage cancer cell DNA and stop growth. It targets a specific area but can sometimes harm healthy cells as well.
External beam radiation sends rays from a machine outside your body, while internal radiation (brachytherapy) places a radiation source near the cancer site. Doctors choose the type and dose based on cancer details and your overall health.
Common side effects include fatigue, skin irritation, hair loss near the treatment area, low blood cell counts, swelling, and pain. Skin protection steps like avoiding tight clothing and using mild soap can help.
Cancer treatment often involves radiation therapy, which uses high-energy waves to damage or destroy cancer cells.
The waves stop cancer cells from growing and making more cancer cells by affecting the
inside of them. However, it can sometimes damage noncancerous cells.
Radiation therapy targets an affected area with high-energy waves, often the location of a tumor or the place where a tumor was removed during surgery to destroy any remaining cancer cells.
This type of treatment is sometimes ideal because it allows doctors to only affect specific parts of your body, unlike other cancer treatments like
that can affect cells in your entire body.
According to the American Cancer Society,
of people with cancer undergo radiation therapy. It can be your only treatment. Or, you might receive it with other types of treatment, such as surgery and chemo.
A person undergoes external beam radiation therapy. (BSIP SA / Alamy Stock Photo)There are two types of radiation therapy: external beam radiation (EBRT) and internal radiation.
Your doctor will consider many factors when deciding which is best for you, including:
cancer type
tumor size
location of cancer
the proximity of cancer to other tissues sensitive to radiation
your overall health and well-being
whether you’ll need other cancer treatment
your age
External beam radiation therapy (EBRT)
With
, a large machine sends radiation waves to the site of cancer from outside the body.
You can’t see the rays, and the apparatus doesn’t touch you but moves around you. The movement allows it to send the radiation from many different directions.
Doctors use this type of radiation as a local treatment to target a specific part of your body. For example, when used for
, the radiation is targeted only at your chest instead of your whole body.
Internal radiation therapy (brachytherapy)
With internal radiation, aka
, a doctor may implant a source of radiation into your body near the cancer site. The sources of radiation are often in the form of:
capsules
ribbons
seeds
balloons
wires
tubes
liquid
This process usually takes place inside an operating room in order to contain the radiation. Doctors and technicians typically use imaging tests to ensure the implant goes to the correct place.
You may receive general anesthesia to put you to sleep during the procedure or local anesthesia to numb the area where you’re receiving the implant.
Depending on the strength of the radiation and the size and location of the implant, you may need to stay in the hospital for a
for treatment. If your implant is smaller, you may be able to go home after treatment, but you’ll likely have specific guidelines and precautions to follow.
When receiving radiation in the liquid form, it’s administered via the mouth,
, or injection. Your bodily fluids may also give off radiation for some time after the test. For skin cancers, this type of radiation may be applied directly to the skin.
Radiation therapy is an essential tool for treating cancer. The main goals of radiation therapy are to shrink tumors and kill cancer cells. Doctors often use radiation therapy with other therapies, such as
or surgery.
There are many reasons why doctors may choose to treat cancer with radiation. They use it to:
destroy all cancer cells
shrink the tumor
stop cancer from coming back
treat cancer symptoms
Radiation therapy may help relieve pain by preventing cancer cells from growing and reducing the amount of
around the part of your body where the cancer is. It may not cure the cancer, but it may help halt its growth and increase your quality of life with less discomfort.
Every person reacts to radiation therapy differently. It’s best to consider that side effects are possible, though you may not experience all of them.
The location and type of cancer, along with your general health, may affect the severity and number of side effects. Any pre-existing conditions you had before receiving a cancer diagnosis may also affect how you respond to treatment.
Some side effects can be seen at the time of treatment, immediately after, or within a few weeks. However, you may experience long-term side effects months or years after radiation. Consider discussing and planning for these side effects with your doctor in advance. They can help determine how to prevent or manage side effects when possible.
The most common side effects of radiation therapy can include:
fatigue
skin irritation (
)
around the site of radiation
low blood cell counts
fluid buildup (
), especially for
pain
Radiation therapy can also have very specific side effects depending on the body part receiving the radiation.
For example, if you’re receiving
, you may be more likely to experience headaches as a side effect. Nausea and vomiting are more common if you receive radiation to your abdomen. Radiation to your pelvis may affect
.
Radioprotective drugs
Your doctor may prescribe medication, known as
, that work to protect healthy tissue from radiation. These medications only work for certain types of radiation and parts of the body but may be effective in reducing side effects.
A team of doctors, including a radiation
and
, will determine your proper course of treatment. The team will also assess the dose and radiation frequency best suited for your cancer type and stage.
Preparation for external radiation therapy involves a radiation simulation. It typically includes the steps seen below.
External radiation therapy can take place during treatment sessions several days a week for multiple weeks. Often, the person is given each weekend off from therapy, which helps restore healthy cells.
Sometimes, people receive radiation therapy less often or as a one-time dose. For some IV radiation treatments, it may take place once every few months.
The total number of treatments depends on the size and type of cancer.
At each session, you’ll lie on the treatment table, and your team will position you and apply the same types of cushions and restraints used during your initial radiation simulation. They may also position protective coverings or shields on or around you to protect other body parts from unnecessary radiation.
Radiation therapy uses a linear accelerator machine, which directs radiation at the appropriate spot. The machine may move around the table in order to direct the radiation at the appropriate angles. The machine may also make a buzzing sound.
You should feel no pain during the session. You’ll also be able to communicate with your team via the room’s intercom, if necessary. Your doctors will be nearby in an adjacent room, monitoring the session.
During the weeks of treatment, your care team will closely monitor your treatment schedule and dosing, and your general health.
You’ll undergo several imaging scans and tests during radiation so your doctors can observe how well you’re responding to treatment. These scans and tests can also tell them if they need to make any changes to your treatment.
If you experience side effects from radiation — even if they’re expected — tell your doctor at your next appointment. Sometimes, even small changes can make a big difference in limiting side effects. At the very least, you may receive advice or medication to help ease the discomfort.
Radiation therapy is a cancer treatment that uses high-frequency waves to destroy cancer cells. You can receive it externally from a machine or internally through medications or injections to the affected area.
Doctors determine the type of radiation and dose based on the type and location of the cancer, your general health, and other factors. They determine the dosage to kill cancer cells while sparing healthy cells.
Radiation therapy may cause side effects, including fatigue, skin irritation, and hair loss, among others. However, you may manage or limit some side effects through other treatments or practices.