Radiation therapy for lung cancer uses high-energy X-rays (photons), particle beams (protons), or other waves at tumors to damage cancer cells and stop them from being able to function. Radiation therapy is known as a local therapy because it is focused directly on the tumor instead of treating the entire body.
Other treatments may be used along with radiation therapy for lung cancer, depending on your overall health as well as the type, stage, and location of cancer.
Types of radiation therapy
External beam radiation therapy (EBRT) uses precisely aimed X-ray or particle radiation beams to target tumors in the body. During treatment, you’ll lie on a table and a machine will move around you. Treatments are painless and may be given daily or multiple days a week for several weeks.
There are several types of EBRT:
3D-conformal radiation therapy (3D-CRT) uses CT or PET scans to create an image of the tumor and the healthy tissues around it before treatment begins. These images are used to aim the radiation directly at the tumor while protecting the healthy tissues.
Intensity-modulated radiation therapy (IMRT) is similar to 3D-CRT but uses small “beamlets” of radiation aimed at the tumor. Radiation strength can be changed throughout treatment to protect nearby healthy tissue. It’s often used when tumors are located near other organs. It has fewer side effects than other types of external radiation, but the treatment times can be longer.
Image-guided radiation therapy (IGRT) uses CT, MRI, or PET scans during treatment. This helps direct the beam precisely and monitor treatment progress.
Stereotactic radiation, also called stereotactic body radiotherapy (SBRT) or stereotactic blative radiotherapy (SABR), is a very precise form of radiation that focuses on 1 small area. This form of radiation therapy uses with a very high dose of radiation and is typically given in only 1 to 5 treatments.
Biology-guided radiation therapy (BgRT) is a type of SBRT that uses an injected radioactive tracer and real-time PET imaging, allowing for precise targeting of the tumor and accounting for movement.
Particle beam (proton) therapy uses a high-energy beam of protons, which are positively charged particles. At high energy, protons can kill cancer cells with much less damage to the healthy tissue near the tumor. This treatment is offered only at select centers in the U.S. and can be used in clinical trials to treat special lung cancer cases.
Tumor treating fields (TTFields) are a different type of radiation that uses lower energy than traditional radiation therapy. It delivers a mild electrical current to the body through electrodes that are connected to a wearable device. The mild electrical current is specifically designed to disrupt the growth of cancer cells, while having little effect on healthy cells. It is approved for use in non-small cell lung cancer that has spread to other areas of the body.
Brachytherapy is radiation therapy that is implanted inside the body. Radioactive material is sealed inside needles, seeds, wires, or a small tube and placed directly into or near a tumor. It allows a high dose of radiation to be delivered inside the tumor while avoiding nearby healthy tissue. You may need to be put to sleep using anesthesia and require an overnight hospital stay when receiving brachytherapy.
Radiation and the brain
Lung cancer brain metastasis (brain mets) is lung cancer that has spread (metastasized) to the brain. There are a few types of radiation therapy that can be used to treat brain mets. They include:
- Stereotactic radiosurgery (SRS) uses a very precise form of radiation to target a tumor and avoid nearby healthy brain tissue. It is often given over 1-5 treatments.
- Whole-brain radiation is external beam photon radiation given to the entire brain. It may be used when there are multiple areas of cancer in the brain that need to be treated.
- Hippocampal-sparing radiation may be used during whole-brain radiation to reduce the risk of memory loss which can be a side effect of whole-brain radiation.
Prophylactic cranial irradiation (PCI)
Prophylactic cranial irradiation (PCI) is a low-dose radiation treatment aimed at reducing the risk of brain mets in people with small cell lung cancer (SCLC). The purpose of PCI is to destroy potential cancer cells in the brain that are too small to be seen on MRI scans.
This treatment can be an option for some people with SCLC who don’t have visible brain mets on MRI. However, there is ongoing debate among experts about the use of PCI, because its benefits remain unclear and there are possible long-term side effects that can impact quality of life. For these reasons, it’s important to discuss the possible benefits and risks with your healthcare team.
For more information, see our booklet Prophylactic Cranial Irradiation: A Decision-Making Tool.
When is radiation therapy used to treat lung cancer?
Radiation therapy for lung cancer is approved for all stages of both non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). It can be used:
- To treat lung cancer that has spread in the body or to the brain
- To lessen symptoms such as pain or difficulty breathing
- Before, after, or along with other lung cancer treatments
You and your radiation oncologist will discuss the type of radiation therapy, how often it will be given, the dose, and the number of treatments that are best for you.
What are the side effects of radiation therapy?
The side effects of radiation for lung cancer depend on the area of your body that receives the radiation, how long you receive treatment, and your body’s individual response. You may not have any side effects or you may have just a few. It is always important to talk with your healthcare team about ways to manage side effects before they develop because they can often be prevented, treated, or eased with healthy practices, medicines, or palliative care services. Cancer treatments have improved over time and so has side effect management.
Side effects of radiation for lung cancer can include:
- Mild or moderate fatigue that may last a few weeks after radiation has ended
- Skin irritation or hair loss in the area where radiation is given
- Sore throat or trouble swallowing if radiation was given near the throat
- Diarrhea if radiation is aimed near the lower stomach
- Memory loss if radiation was used on the brain
Less common side effects of radiation for lung cancer can include:
- Radiation pneumonitis is a rare form of pneumonia, sometimes caused by radiation, and can occur 2 to 6 months after treatment is completed. Contact your healthcare team if you have shortness of breath, chest pain, a cough, or a low fever after finishing radiation therapy. Radiation pneumonitis is diagnosed with a chest X-ray. There are usually no lasting problems once the pneumonitis is treated.
- Radiation fibrosis is scarring of the lungs caused by radiation therapy. The amount of scarring depends on the number of radiation treatments and the strength of the dose. Fibrosis can sometimes cause shortness of breath and coughing. If scarring develops, your healthcare team may recommend oxygen to ease your breathing.
Call your healthcare team right away if you have any of the following:
- Trouble breathing, chest pain, fainting, dizziness or confusion
- Diarrhea with bad cramping or pain, blood in the stool or urine or dark urine
- Fever of 100.5 degrees Fahrenheit or higher
- Changes in vision, memory, or thinking skills
- Swelling in any part of your body
Questions to ask your healthcare team about lung cancer radiation therapy
Talking with your healthcare team and asking questions ensures you stay informed about your condition and are involved in your treatment plan. The following are some examples of questions to get the conversation going:
- How will the radiation therapy be given?
- How many treatments will I have per week and for how long?
- What side effects should I expect and how do I manage them?
- Will I also need other treatments such as chemotherapy or surgery? If so, when will I receive them and in what order?
- Will I need a special diet during or after my radiation treatment?
- Can I drive myself to and from the treatment facility?
- Will I be able to continue my normal activities during treatment?
- After my treatment is complete, how often will I need to return for checkups?
Explore other questions to ask your healthcare team.
Recent advancements in lung cancer
Explore recent advancements in lung cancer, new treatment approvals, research breakthroughs, and more by signing up for GO2’s email communications.
Frequently asked questions
Where can I find more resources and support?
Contact the GO2 HelpLine at 1-800-298-2436 or email support@go2.org to connect with caring and highly trained staff who listen, answer your questions, and provide support. We offer many free programs and educational resources to meet your needs.
Is radiation therapy painful?
No, radiation therapy is not painful. If you have any discomfort during treatment, tell your radiation therapist, so they can determine the cause and help resolve it.
Will other medications affect radiation therapy?
Most medicines can be continued throughout your radiation therapy without issues. Always give your treatment team a complete list of the prescription and over-the-counter (OTC) medications you take so they can confirm their safety.
How often are radiation treatments?
Some types of radiation therapy for lung cancer require a single treatment, while others can require treatment up to twice a day, 5 days a week, for several weeks. Radiation treatments are usually scheduled during weekdays so that you can rest on weekends. The schedule for radiation treatments is based on the type of radiation you’re receiving and your specific needs.