About Mayo Clinic's program

The Proton Beam Therapy Program is directed by the Mayo Clinic Comprehensive Cancer Center, the only National Cancer Institute-designated comprehensive cancer center in the country with a multisite presence, with locations in Arizona, Florida and Minnesota.

Mayo Clinic's proton beam program incorporates advanced techniques, such as biological dose modeling to ensure you get the exact amount of radiation you need and in-room image guidance to deliver it exactly where you need it. Mayo Clinic experts also use adaptive planning when indicated. With adaptive planning, after each session, a specialist examines how your tumor changes so your next treatment can be adapted to precisely target its new shape.

For people with tumors in or near their lungs, Mayo Clinic's proton program uses an advanced technique called gating. The technique images the lungs during breathing and delivers radiation only when the lungs are at a specific point in the respiratory cycle, ensuring that only the tumor — and not healthy lung tissue — receives radiation.

Mayo Clinic's proton program uses only pencil beam scanning, the most precise form of proton delivery. The pencil beam conforms more closely to the tumor, so specialists can "paint" small spots of protons back and forth through a tumor. The accelerated protons fill the depth and contour of the tumor. The precision of pencil beam scanning makes it especially beneficial in treating tumors adjacent to critical and sensitive organs and structures, such as the brain, eye and spinal cord.

At Mayo Clinic, you'll be cared for by a team of specialists from different fields who work together to determine your treatment options. This team approach means your care is coordinated to meet your needs so that you receive the treatment that's best for you.

Having a multidisciplinary team of experts on your side means that all of your doctors are working toward the same goal. This is especially beneficial when it comes to coordinating complex treatment protocols involving multiple therapies.


Mayo Clinic is leading the way in developing strategies to reduce the number of treatments needed for specific kinds of cancer. For instance, when you're prescribed a radiation dose, it's broken down into small increments called fractions. Breast cancer treatment can be divided into 25 fractions. Prostate cancer treatment can be more than 35.

Through research into the power of proton beams, Mayo Clinic experts are finding ways to reduce breast cancer treatment to between three and five fractions and prostate cancer treatment to five. That shortens the length of treatments from up to two months to one or two weeks.

Mayo Clinic researchers also monitor all proton beam therapy patients and gather data about side effects, tumor control, well-being and more. Researchers use this large database to develop better delivery techniques, care models and services for people with cancer.

Unfortunately, today's best cancer treatment protocols don't yet meet the needs of every person with cancer. To help these patients, Mayo Clinic works with partners across the nation to conduct clinical trials that use experimental treatments. This partnership between institutions and patients can have an immediate impact while developing more-effective treatments options for the future.

How you can help

Mayo Clinic is a nonprofit organization and leader in medical care, research and education. The Proton Beam Therapy Program is funded with Mayo Clinic investments and the help of generous benefactors.

Proton beam therapy is a powerful cancer treatment that helps many people survive cancer with fewer side effects and complications. Thanks to committed benefactors, Mayo Clinic Comprehensive Cancer Center is making exciting strides in cancer therapy. For instance, Richard Jacobson's generous gift helped establish the Proton Beam Therapy Program at Mayo Clinic, and Lawrence and Marilyn Matteson strengthened it so children could have access to this powerful therapy.

Help create a lasting legacy in the battle against cancer by funding the Mayo Clinic Proton Beam Therapy Program. Your philanthropic investment will place you among visionary supporters improving cancer therapy for generations to come.

June 22, 2023