External Beam Radiation Therapy
External beam radiation therapy is the most common form of radiation therapy used to treat lung cancer. It is produced by a machine called a linear accelerator. Short bursts of x-rays are literally fired from the machine at your cancer. The x-rays come out in a square-shaped manner, and the radiation oncologist designs special blocks to shape the radiation beam so that it treats the cancer and as little normal tissue as possible.
Radiation therapy works by damaging cancer cells that, by nature, divide and grow more quickly than normal cells. Once damaged, the cancer cells are unable to grow. Although some normal cells may be damaged in the process, these normal cells are able to repair themselves and function properly. Like chemotherapy, the side effects from radiation result from the injury to the normal tissues. There are many new ways that the radiation oncologist can customize your treatment to try to kill as much cancer while sparing as much normal tissue as possible.
The radiation oncologist will tell you how many treatments you will get; sometimes they will be once a day and sometimes twice per day. Each treatment generally only takes a few minutes, and the total treatment time can range from 5-8 weeks depending on the total dose required.
Radiation therapy, like chemotherapy, can be given to treat the initial cancer in the lung or to treat the cancer once it has spread beyond the lung. Once it has spread beyond the chest, radiation is no longer curative, but the treatments can be helpful to minimize symptoms, including pain, bleeding, cough, or weakness.
Many people believe that once you have received a certain dose of radiation you can no longer get any more treatment. Although each tissue in the body can only safely tolerate a certain dose of radiation, the therapy is very focused, and it is possible that you can get additional treatments to an already treated area or certainly to an area not yet treated. Ask your radiation oncologist about what dose you can safely receive.
“Brachy” means “short,” and endoluminal brachytherapy uses radiation therapy at very short distances. When you receive external beam radiotherapy, the radiation comes out of a machine located about 40 inches above you. Brachytherapy, however, delivers radiation directly to the cancer via a radioactive implant inside the body. This special type of treatment is used at many centers in the United States. Ask your radiation oncologist if it is appropriate for you.
In this procedure, a tube is placed down the bronchus and a radioactive source is placed close to the tumor itself in order to deliver a concentrated dose of radiation to a localized area of tumor. It is especially useful when the lung cancer has obstructed a bronchus or is causing bleeding into the bronchus.
- Fatigue or tiredness
- Mild rash or redness
- Mild to moderate cough
- Mild-to-moderate shortness of breath
- Inflammation or irritation of the swallowing tube
Side effects can be seen long-term (for many months to years after the therapy) and are generally associated with how much of your lung was treated with radiation therapy and how high a dose was delivered. Ask your radiation oncologist how likely it is that you will develop a long-term breathing problem from the radiation therapy.
When to Contact Your Doctor
Contact your doctor if you:
- Develop side effects from the treatment
- Develop new or unusual symptoms
- Notice that your skin is red, blistered, or swollen
- Develop swelling in your neck or arms
- Develop a cough or cough up blood
- Develop a fever, swelling, or bleeding
- Reviewer: Igor Puzanov, MD
- Review Date: 09/2013 -
- Update Date: 09/30/2013 -