External beam radiation

Radiation therapy – including external beam radiation – can help shrink tumors or destroy cancer cells. It’s often used together with other cancer treatments, such as surgery or chemotherapy.

At Atrium Health Floyd and Harbin Clinic, our radiology specialists use advanced types of external beam radiation to effectively treat cancer while minimizing side effects.

What is external beam radiation?

Radiation therapy uses targeted energy (such as X-rays and radioactive substances) to destroy cancer cells and shrink tumors. It also can help ease symptoms related to cancer. Radiation therapy may be a primary treatment or used in combination with other treatments.

External beam radiation is one type of radiation therapy. It uses energy from a machine to target a specific area of the body. It’s referred to as a local treatment because it delivers radiation just to the area where there’s cancer.

You might have external beam radiation to shrink a tumor prior to surgery (called neoadjuvant treatment). Or you might have it after surgery or chemotherapy (adjuvant therapy) to stop the growth of any remaining cancer cells. Radiation can also be used to relieve symptoms of advanced cancer (palliative treatment).

Types of external beam radiation

There are several types of external beam radiation. The treatments differ depending on the type of radiation energy it delivers and how it’s given. The most common types of external beam radiation include:

• Intensity modulated radiation therapy (IMRT): Radiation beams are aimed at a tumor from multiple directions. The intensity of the beams is tailored to your treatment.
• Stereotactic radiosurgery (SRS): Despite its name, this treatment does not involve surgery or incisions. SRS aims high-powered radiation directly at small tumors in the brain and central nervous system.
• Three-dimensional conformal radiation therapy (3D-CRT): Doctors use imaging – such as CT, MRI or PET scans – to carefully plan treatment. The radiation beams conform to the exact shape of the tumor, hitting it directly while sparing healthy surrounding tissue.

Conditions treated with external beam radiation

External beam radiation is a common cancer treatment. Used alone, or in combination with other therapies, it can be used to treat many types of cancer. These include:

• Breast cancer
• Colon cancer
• Head and neck cancer
• Lung cancer
• Prostate cancer
• Skin cancer

External beam radiation side effects

Advanced methods for delivering external beam radiation help reduce some of the side effects of the treatment. The more precisely radiation can be delivered into a tumor, the less affect it has on healthy surrounding tissue.

But even the most precise radiation treatments can lead to some side effects such as fatigue or hair loss. Other side effects include skin changes, such as rashes or irritation at the radiation site.

You may also experience side effects specific to the area of the body being treated:

• Brain radiation can lead to memory issues, headache or vision changes
• Breast treatment can cause swelling (edema)
• Lung cancer radiation can result in cough, shortness of breath or difficulty swallowing
• Head and neck cancer treatment can cause mouth sores, changes to sense of taste and difficulty swallowing
• Radiation to the pelvis can lead to difficulty urinating or incontinence, sexual side effects and reduced fertility
• Radiation to the stomach can cause nausea, vomiting and urinary problems.

Related conditions

Colon cancer

Head and neck cancer

Prostate cancer

Skin cancer