BACKGROUND: More than 1,400,000 men and will be diagnosed with cancer in the United States this year. Cancer will kill more than 550,000 people. Scientists and doctors are constantly coming up with new ways to defeat this deadly disease. One of the frontline treatments for cancer is radiation. Focused radiation kills cancer cells. There are some drawbacks, however. If the radiation is not focused precisely on the cancer cells, healthy tissue can be affected as well. Women with breast cancer often experience burns and scarring around the areas treated with radiation. Men with prostate cancer face incontinence and impotence if tissues around tumors are damaged. Researchers have come up with new ways to deliver radiation, including radioactive pellets implanted in the tumor and radiation emitters mounted on robotic arms.

PROTON THERAPY: Conventional radiation therapy is like shooting tumors with a bullet. The X-rays pass through the body, affecting healthy and diseased tissue. Like a bullet, X-rays leave a track of damage. Because of the damaging side effects, doctors often use a lower dose of radiation with conventional therapy. Protons can be more precisely targeted than X-rays. Protons deposit the majority of their destructive energy at the site targeted by doctors. Normal, healthy tissue receives less exposure to radiation, and patients experience fewer side effects. This allows doctors to prescribe a higher dose of radiation than would be safe with conventional therapy. More radiation in fewer treatments gives patients a better chance of beating their cancer.

HOW IT WORKS: Protons are hydrogen atoms after its electrons have been removed. A machine called a cyclotron energizes protons. Magnetic fields direct the particles into the tumor. How deeply the radiation penetrates is calculated based on the tumor's location. The radioactive particles destroy the DNA cells it comes in contact with, which eventually kills the cells. The protons can be manipulated to travel a certain distance before delivering its radiation. This is how a precise attack on a tumor can be calculated.

MORE FACTS FROM THE NATIONAL ASSOCIATION FOR PROTON THERAPY:

» The therapy is a highly effective treatment for tumors in the head, brain, neck, lung and prostate.

» Researchers are studying ways to breast cancer in the near future, as well as other areas of the body.

» Treatment time can take from one day to seven weeks depending on where the cancer is located.

» Loma Linda University Medical Center opened the world's first hospital-based proton treatment facility in 1990.

» Proton therapy is covered in the United States by Medicare and most insurance providers.