Explore Proton Therapy

Two Proton Therapy Treatment Centers, One Expert Team

Mass General has the only proton therapy site in all of New England, with two proton therapy centers.

Since the opening of the Francis H. Burr Proton Therapy Center in 2001, we have treated thousands of adult and pediatric patients with proton therapy. In 2020, we expanded clinical operations on our main campus location with the opening of a second center, the Gordon-Browne Proton Therapy Center, making Mass General the only institution on the East Coast to have two proton therapy centers. Both state-of-the-art treatment centers offer the latest technology for patients and are run by one talented, multidisciplinary team.

Both of our proton therapy centers are located on Mass General's main campus in Boston, giving patients access to a wide range of world-class care and services.

Pioneers of Proton Therapy

Working with the Harvard Cyclotron Laboratory (HCL), Mass General physicians became the first in the world to discover how to harness the extraordinary physical characteristics of high energy protons for medical care. By using protons rather than conventional x-rays (photons), physicians could increasingly concentrate radiation energy in tumors and intended targets, reducing radiation dose and damage to nearby healthy tissue.

Proton Therapy Research

As part of the largest hospital-based research program in the country, we have led, and continue to lead, many studies to define the best use of proton therapy for clinical care. Learn more about our groundbreaking proton therapy research.

View radiation oncology clinical trials.

What is Proton Therapy?

Proton radiation therapy, also called proton beam therapy, offers an advanced form of radiation treatment meant to eliminate tumor cells. Instead of using traditional X-ray (photon) beams to deliver radiation to the tumor, proton therapy uses a high-energy, focused proton beam to target the tumor precisely, with less collateral radiation delivered to surrounding normal cells and tissue. Advantages of proton beam therapy include potential less side effects from radiation treatment and an increased concentration of radiation in the desired target which may improve tumor control and disease curability.

Infographic explaining the difference between photo radiation and proton radiation

How Does Proton Therapy Work?

Gordon-Browne Proton Therapy Machine
The proton therapy machine located in the Gordon-Browne Proton Therapy Center.

Proton therapy uses a special machine called a cyclotron or synchrotron to accelerate protons. Protons are extracted from the particle accelerator and directed with magnetic fields directly to the tumor for proton therapy. The depth of penetration of the protons is related to their energy and can be precisely controlled to match the location of the tumor, limiting radiation exposure elsewhere.

Protons deliver most of their energy to a narrow volume within the body. This unique dose delivery property of protons is known as the Bragg Peak. We can manipulate the Bragg Peak region to deliver the desired radiation dose to the tumor itself without any exit dose beyond the tumor. Conventional external beam radiation therapy uses photons, also referred to as x-rays, that enter and exit through the body. The special properties of protons generally reduce the radiation dose to the normal tissues surrounding the treatment site.

What Types of Cancer Can be Treated with Proton Therapy?

Proton therapy is used to treat both benign and malignant tumors. Proton treatments are particularly important for treating tumors that haven't spread and are near crucial body functions, such as the brain, spinal cord, or eyes. Doctors commonly select proton therapy to treat cancers in children due to the increased sensitivity of children to even low dose radiation which can affect growth and development. In addition to these priorities, there is increasing investigation to use proton therapy for all types of cancers from head to toe. Our expert radiation oncologists can help determine if proton therapy is right for you.

Common conditions we treat with proton therapy include:

Shannon MacDonald, MD
Shannon MacDonald, MD

What Are the Advantages of Proton Therapy?

The precise nature of proton beam therapy has multiple benefits for the patient. Typically, a proton treatment delivers up to 60% less radiation to healthy tissue, reducing the radiation damage around the tumor. This concentrated dose of proton beam therapy also means the tumor receives a higher level of radiation, improving the odds of eliminating it. The targeted nature of proton beam therapy often results in less severe side effects for the patient.

What Are the Side Effects of Proton Therapy?

All radiation therapy has side effects. Proton therapy's side effects are similar to other radiation treatments but may occur less often and may be milder due to the limited exposure of radiation to healthy cells. Common side effects may include soreness near the treatment area, low energy following treatment, headaches and hair loss at the treatment spot.

We're Here to Help

We encourage potential patients to seek referrals through their primary care provider (PCP) or local radiation oncology specialists. Both patients and providers can call our proton inquiry line at 617-724-1680 or email InformationRadOnc@partners.org with questions.

Pre-certification from your insurance provider is required to receive proton therapy. We recommend you contact the Customer or Member Services Department at your insurance company (the phone numbers are on your insurance card or in your benefits booklet) to ask about your network coverage and specific proton therapy benefits. We have a dedicated team of insurance coordinators that can help you navigate this process. Learn more.

Proton Therapy Patient Stories

Explore real-life stories of individuals with cancer who have been treated with proton therapy at Mass General Cancer Center. Discover the healing power of advanced treatment with reduced side effects, and the supportive role that expert providers and loved ones play that makes all the difference.

View patient stories


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Proton Therapy FAQs

Proton Therapy FAQs

View the answers to frequently asked questions about proton therapy.



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Proton Therapy Videos

Learn how proton therapy works, and how the proton therapy team at Mass General Cancer Center is committed to providing patients with highly customized, team-based proton therapy treatment.