External Beam Radiation Therapy

As the name describes, external beam radiation therapy starts from outside of the body. Radiation beams are aimed at specific areas of the body where cancer cells are located. This is the most common form of radiation therapy.

External beam radiation therapy is typically done with the use of a machine called a linear accelerator that emits high-energy x-rays targeted at a specific area(s) in the body. Doctors may use a few or many radiation beams to treat your cancer. Depending upon the type of external radiation therapy you receive, the radiation beams can be angled to come from multiple directions, or “shaped” to match the outlines of your tumor and to minimize the amount of radiation going to healthy tissue. Specialists also can vary the amount of radiation coming from each beam, thereby customizing your specific cancer treatment.

External beam radiation therapy is done on an outpatient basis. Treatments are typically done five days a week. Your doctor will let you know how many weeks you will undergo treatment. It can be two or more weeks depending upon the type and location of your cancer. Each treatment is given in short, daily sessions that can take 20 – 30 minutes.

Your doctor will discuss with you the options for your type of cancer and then arrange for pre-treatment planning to map out the exact location of your cancer and define the amount and angle of radiation to be used.

In addition to high energy x-rays, there are other types of external radiation options available. Those include the use of gamma rays or proton beams, among others.

At Siteman, we offer several types of external beam radiation therapy: