Lung Cancer: Radiation Therapy

Radiation therapy uses high-energy beams (x-rays) to destroy cancer cells by damaging their DNA. It is very effective at controlling or eliminating tumors at specific sites in the body. 

Radiation therapy can be given as a curative therapy to patients whose lung cancers are confined to the chest but cannot be removed surgically. Using the most-advanced technologies, we can now deliver powerful doses of radiation directly to the tumor with exquisite precision. The approaches we use can reduce the number of sessions required for radiation treatment in comparison with more-conventional approaches, while also limiting the risk of side effects.

Radiation therapy can also be used as a palliative measure to improve quality of life among patients whose disease does not respond to surgery or chemotherapy.

Our radiation team works together to offer the highest level of safety during every step of your treatment. Highly trained medical physicists work in subspecialized teams with the radiation oncologists to create an individualized radiation treatment plan for every patient. Radiation therapists are present during each radiation procedure to ensure that the correct dose of radiation is being delivered precisely where it is needed.

Radiation Therapy for Non-Small Cell Lung Cancer

Radiation therapy for early-stage non-small cell lung cancer, which consists of a single small nodule in the lung without any spread to nearby lymph nodes, is typically given as stereotactic body radiation therapy (SBRT). SBRT has been highly successful in treating small lung lesions with excellent long-term chances to eradicate them. It is therefore the standard of care for patients who cannot be treated surgically.

Radiation therapy is given in place of surgery for patients with advanced non-small cell lung cancer that has spread to the lymph nodes but is still confined to the chest and who cannot be treated surgically either because of a tumor’s location or because of the patient’s health. It is ideally given with chemotherapy administered either at the same time or before or after radiation therapy. These treatments typically last about six weeks, with five daily treatments per week.

Patients who have advanced non-small cell lung cancer that is confined to the chest and who have their tumor surgically removed may be treated with a five-to-six week course of radiation therapy before or after their surgery depending on their specific situation.

Radiation Therapy for Small Cell Lung Cancer

At Memorial Sloan Kettering, the approach your doctors recommend will depend on the stage of your disease.

People with limited-stage small cell lung cancer confined to the chest simultaneously receive a combination of chemotherapy and radiation therapy to shrink the tumor. Radiation therapy for limited-stage small cell lung cancer can be administered either once or twice a day. The treatment course lasts between three and seven weeks.

People with extensive-stage cancer typically receive chemotherapy only. Radiation therapy can be given to help improve symptoms such as pain, headaches, or weakness from brain lesions. The treatment course typically lasts for two to three weeks, with five daily treatments per week.

In many people, small cell lung cancer metastasizes or spreads to the brain, even after a positive response to initial treatments. Prophylactic or preventive cranial irradiation is a whole-brain radiation therapy that can help prevent the development of brain metastases and improve survival in patients with limited- and extensive-stage small cell lung cancer who show a response to treatment with first-line chemotherapy or chemotherapy and radiation therapy.

Types of Radiation Therapy

Intensity-Modulated Radiation Therapy (IMRT)

Memorial Sloan Kettering radiation oncologists pioneered and have extensive experience using a form of external-beam radiation therapy called intensity-modulated radiation therapy (IMRT) to treat lung cancer. Following a CT scan that maps the tumor in three dimensions, IMRT uses sophisticated computer programs to calculate and deliver variable doses of radiation directly to the tumor from different angles. This technology targets a tumor while sparing the healthy tissue that surrounds it. It enhances your radiation oncologist’s ability to administer a lethal dose of radiation to a lung tumor, increasing your chance for cure.

Image-Guided Radiation Therapy (IGRT)


Radiation oncologist Josh Yamada talks about a technique called IGRT that delivers high doses of radiation precisely along the contours of a tumor.


Imaging tests play a crucial role in helping doctors to accurately plan and effectively deliver radiation therapy. Some patients with lung cancer may be treated with a specialized form of intensity-modulated radiation therapy called image-guided radiation therapy (IGRT). IGRT involves the use of sophisticated imaging tests to verify the position of the patient and the location of the tumor prior to and during the delivery of the treatment.

This procedure requires no anesthesia and side effects are less likely than with traditional methods.

We treat approximately 400 patients with non-small cell lung cancer each year using IGRT to the chest as well for lung cancer that has spread to other areas of the body.

Memorial Sloan Kettering pioneered the integration of PET imaging into the radiation treatment planning process. The traditional method of using a CT scan to target the tumor can sometimes damage normal tissue containing no cancer cells. PET simulator technology enables our doctors to more precisely — and safely — target the tissue containing cancer cells and avoid harming healthy tissue, resulting in better treatment for our patients. We have a dedicated MRI simulator that allows us to pioneer the next level of imaging precision into the radiation treatment planning process.

Stereotactic Body Radiation Therapy (SBRT)

Stereotactic body radiation therapy (SBRT) is a treatment for non-small cell lung tumors that are small in size and confined to the lung. It can also be used to treat lung metastases. SBRT combines image-guided radiation therapy with even more advanced techniques to deliver extremely high doses of radiation to the tumor while minimizing the dose to normal structures nearby. It usually requires fewer treatments than other forms of radiation therapy, and leads to better outcomes and fewer side effects than conventional radiation therapy. This procedure requires no anesthesia, and usually has fewer side effects than traditional methods.

Proton Therapy

For some cases of lung cancer, our radiation oncologists can use proton therapy, an advanced form of radiation therapy, to deliver high doses of radiation to tumors that may be resistant to conventional forms while minimizing exposure to the surrounding healthy tissues. Proton therapy directs its cancer-fighting energy to precise locations within the body, allowing our doctors to deliver the necessary dose to the tumor — maximizing the chance of destroying it — while simultaneously lowering the dose to normal tissues and thereby reducing the risk of treatment-related side effects.  Currently, this cutting-edge technology is available at only 14 locations in the United States.   


Some patients with lung cancer may be candidates for intraoperative radiation therapy, a brachytherapy procedure in which we deliver radiation therapy during surgery in order to help decrease the risk of cancer recurrence. We are also able to deliver high doses of radiation to the airways using a specialized approach called endobronchial brachytherapy. This localized form of radiation therapy may be useful in selected patients with tumor recurrence in the larger airways.

Palliative Radiation Therapy

While radiation therapy is generally not used to treat cancer that has metastasized or spread to the second lung or to other parts of the body, many patients receive radiation to treat symptoms that are caused by metastases. For example, symptoms such as headache and weakness caused by metastases in the brain, or pain caused by metastases to the bone can be treated with radiation therapy. The goal of these treatments is to improve the quality of life for patients who are not candidates for surgery or radiation therapy.

Clinical Trials in Radiation Oncology

For some patients, the best strategy may be to enroll in a clinical trial that evaluates new radiation techniques or combinations of surgery, chemotherapy, and radiation therapy.

Many of our clinical trials aim to further improve the precision of our imaging and radiation delivery techniques. Our goal is to minimize damage to surrounding normal tissues and maximize the effectiveness of the radiation treatment to the tumor.

We are also studying several targeted drugs in combination with radiation therapy to understand the interaction between radiation therapy and the immune system to fight cancer.

By choosing Memorial Sloan Kettering for your care, you may gain access to new treatments that are not widely available elsewhere. Participating in a clinical trial is one way for you to make a valuable contribution toward progress against lung cancer.