Radiation Oncology Frequently Asked Questions
- How does radiation therapy work?
- What steps will occur during my therapy?
- How long are my treatments?
- What type of equipment is used during radiation therapy?
- Will I feel the treatment as it is being given?
- Am I radioactive?
- Is my hair going to fall out?
- What are the side effects of radiation treatment?
- What is the difference between chemotherapy and radiation therapy?
- Is there some type of lotion to put on my skin before and after treatment?
- Is there anything I can eat to boost my immune system?
- What is brachytherapy?
- Are brachytherapy seeds removed after treatment?
- What is three-dimensional conformal radiation therapy (3-D CRT)?
- What is intensity modulated radiation therapy?
- What is stereotactic hypofractionated radiation therapy?
- What is gamma knife radiosurgery?
- What is interstitial radiation therapy?
- Is proton beam therapy useful for treating my prostate cancer?
How does radiation therapy work?
Radiation therapy destroys cancer cells by dismantling their RNA so that the cells cannot multiply and spread. Healthy tissue that receives radiation also will be affected, but healthy cells are able to recover.
What steps will occur during my therapy?
At your initial consultation, the radiation oncologist will review information about your diagnosis, including the expected outcome, potential side effects and reasonable alternatives to radiation therapy, if there are any.
Next, he or she does what is called a simulation to plan your treatment. This includes having a CT scan, measuring and marking the location to be treated, and taking photos. Care is taken to ensure that the radiation is delivered precisely to the tumor, thus sparing your normal surrounding tissue.
After the simulation is done, a field verification is performed to ensure that the treatment being planned meets all safety and quality assurance standards. When the field verification has been completed, treatment can begin.
During your treatment you are being carefully monitored. Occasionally x-ray films are taken during the procedure to make sure you are positioned accurately.
How long are my treatments?
Usually, external beam radiation therapy is delivered in a series of treatments over five to six weeks, on a Monday through Friday schedule. The appointments usually last 15 to 20 minutes, although the radiation treatment is only one to two minutes in length.
Treatment with internal radiation, such as brachytherapy (radioactive seeds or other implantable devices) is given over a shorter duration of time but you may need to be in the hospital for this procedure.
What type of equipment is used during radiation therapy?
A linear accelerator (LINAC) is used to deliver what is called an external beam of radiation to the tumor. "External beam" means that the radiation source originates outside of the body. Intensity modulated radiation therapy (IMRT), for example, is a type of external beam radiation treatment. Radiation therapists operate the linear accelerator.
There are also therapies in which radiation is placed directly within the body. Brachytherapy is an example of this type of treatment.
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Am I radioactive?
You are not radioactive when you have external beam therapy. If you have had an implantable device placed, you may have higher than normal radioactivity levels for a period of time, and will be advised by the medical staff about precautions to take.
Is my hair going to fall out?
Hair loss may occur in the treated area. You are more likely to lose your hair if you are also being treated with chemotherapy. However, not all chemotherapy drugs cause hair loss.
What are the side effects of radiation treatment?
Side effects may include swelling and sunburn-like changes in the treated area. Usually these changes in tissue and skin go away in six to 12 months. Fatigue may also occur, and some patients experience a temporary loss of appetite.
What is the difference between chemotherapy and radiation therapy?
Chemotherapy uses powerful drugs that are toxic to cells. Radiation therapy uses high energy radiation to shrink tumors and kill cancer cells.
Is there some type of lotion to put on my skin before and after treatment?
We do not recommend using a lotion before treatment. If you experience sunburn-like changes in your skin after treatment, you may use a commercially available lotion sold in most drug and grocery stores which hydrates and replenishes the skin.
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Is there anything I can eat to boost my immune system?
There is nothing you can eat to boost your immune system before receiving radiation therapy. However, eating a healthy, balanced diet is always recommended.
What is brachytherapy?
Brachytherapy is the implantation of radioactive "seeds" or other implantable devices near the tumor. These devices deliver a high dose of radiation to the tumor while sparing the surrounding non-cancerous tissues.
Physicians at Virginia Mason were the first in the Pacific Northwest to use an advanced technique known as "real-time dosimetry" to precisely place radioactive seeds with millimeter accuracy.
Are brachytherapy seeds removed after treatment?
The radioactive seeds that have been placed in the prostate gland, for example, or in the surgically removed tumor site are not removed. They gradually lose their radioactivity over time.
What is three-dimensional conformal radiation therapy (3-D CRT)?
With this type of radiation therapy, a CT image is taken of the tumor to conform the radiation beams to the size and shape of the tumor. The tumor is then exposed to several beams of radiation from different angles.
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What is intensity modulated radiation therapy?
This therapy – a form of three-dimensional conformal radiation therapy (3-D CRT) – delivers highly focused radiation beams to the tumor or to areas within the tumor. Treatment planning begins with three-dimensional CT computer imaging that conforms the radiation beams to the size and shape of the tumor(s). The beams of radiation can be controlled or "modulated" in intensity and are delivered with high-precision accuracy that lessens damage to surrounding healthy tissue.
What is stereotactic hypofractionated radiation therapy?
This technique uses external beam radiation therapy delivered in a precise manner to the tumor, allowing for significantly reduced treatment visits. With SHARP therapy (Stereotactic Hypofractionated Accurate Radiotherapy of the Prostate), for example, which Virginia Mason radiation oncologists pioneered, treatment time was reduced from the standard eight weeks to five days.
What is gamma knife radiosurgery?
This type of radiation delivery is not surgery in the usual sense but is instead a procedure that uses high-dose and highly focused beams of radiation from different angles directed toward a small tumor(s). (This therapy is also called stereotactic radiosurgery.) Gamma knife radiosurgery was developed specifically for treatment of brain tumors.
Several specialists (radiation oncologists, neuroradiologists and neurosurgeons), along with other members of the radiation oncology team, may be involved in the treatment planning using this technique. During the procedure, a rigid frame is put in place to keep the head still. Treatment duration depends on the shape and location of the tumor, and the dose of radiation required.
What is interstitial radiation therapy?
Interstitial radiation therapy is therapy using implantable radioactive devices, such as radioactive seeds, as opposed to receiving therapy from an external beam. It is also called brachytherapy.
Is proton beam therapy useful for treating my prostate cancer?
Proton therapy for prostate cancer has been in existence for decades, although lately there is more publicity surrounding this form of treatment. It has not been shown to improve outcomes for prostate cancer, despite significantly higher costs. Read clinical studies and commentary about proton therapy:
- Comparative effectiveness study of patient-reported outcomes after proton therapy or intensity-modulated radiotherapy for prostate cancer
- The Titanic and the Iceberg: prostate proton therapy and health care economics
- Choosing Wisely: Five Things Physicians and Patients Should Question