ANSWER: Proton beam therapy is a type of radiation therapy used to treat cancer. Unlike standard radiation therapy using X-rays, which travel all the way through a person’s body, protons go to the tumor, release their energy and stop. That means proton beam therapy tends to be more effective, and causes fewer side effects, than standard radiation therapy.
Protons are subatomic particles that combine with neutrons to form the nucleus of an atom surrounded by orbiting electrons. Radiation is energy released from atoms as either electromagnetic waves — such as X-rays or gamma rays — or as tiny particles, such as electrons or protons. For more than 120 years, radiation has been used to destroy cancer cells.
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