Precise Treatment of Complex Tumors

Proton beam surgery is a highly sophisticated form of radiosurgery. The beam of proton radiation can be very precisely aimed at a tumor with little harm to the surrounding healthy tissues.

Traditional radiosurgery using x-ray or gamma radiation can be highly effective for small, spherical lesions. For larger, more irregularly shaped lesions, however, it becomes more difficult to deliver a uniform dose of radiation to the target without affecting outlying tissue. In these cases, proton radiation has significant advantages:
  • Delivers most of its radiation into the intended target
  • Beams conform to the shape of the lesion
  • Normal tissue outside the target receives little or no radiation
  • We use radiosurgery to supplement traditional surgery or in some cases replace it entirely, depending on the nature and location of the abnormality. It is an effective treatment for:
  • Benign lesions such as meningiomas, acoustic neuromas and pituitary adenomas
  • Malignant lesions such as gliomas and metastases
  • Vascular abnormalities of the brain, particularly Arteriovenous malformations (AVMs)

Proton beam radiosurgery can also be used as part of a treatment program for chordomas, certain chondrosarcomas of the spine and skull base, and other types of tumors. 

Careful Planning for Better Results

To ensure complete and accurate care, the general pre-treatment process follows a similar course.

Prior to proton treatment the patient’s medical history, including imaging studies, are reviewed to ensure that proton therapy is appropriate
  • It may be necessary to obtain additional tests to update the medical record
  • Patients accepted for proton therapy undergo a simulation process to enable proper planning prior to treatment. This process involves making an immobilization device to help the patient maintain a steady body position during the proton treatment. Using the custom immobilization device, treatment planning X-ray images are obtained to help delineate the lesion(s) or target(s) and map their position within the body
  • When patients come for their proton treatments, images are taken using state-of-the-art X-ray or ultra-sound technology. These pre-treatment images are compared to the planning images to ensure high precision alignment 

Treating People, not just Diseases

All of our surgeons, nurses and radiation therapists take pride in knowing their patients and families.

Our nurses educate patients and their families and provide important emotional support. In addition, we offer comprehensive support services on Mass General's main campus:

  • Cancer-related counseling by social workers
  • Nutritional support from registered dietitians
  • Holistic therapies such as massage, art and music
  • A hair-loss and cosmetic boutique
  • Parenting assistance 

An Unmatched Level of Experience

Radiosurgery at Mass General is performed at the Francis Burr Proton Therapy Center, which is jointly funded by the hospital and the National Cancer Institute. The Proton Beam Unit was founded in 1962 and has the most experience with stereotactic radiosurgery of any center in the United States.

The Proton Therapy Center provides a complete range of services for the diagnosis and radiosurgical treatment of brain and spinal tumors and arteriovenous malformations (AVMs). Patients may come to the center for:

  • Consultation
  • Care in partnership with referring physician
  • Complete treatment and management 

Radiosurgery Pioneers

Producing a proton beam requires a cyclotron, a machine that accelerates subatomic particles to nearly the speed of light. The Harvard Cyclotron Laboratory, one of the world's first such facilities, was built in the 1940s for research in nuclear physics.

In the early 1960s, researchers from Mass General and Massachusetts Eye and Ear began working with the cyclotron staff to treat patients using proton beam therapy. Its first application was for benign tumors of the pituitary gland.

The Proton Beam Unit opened in its current location on the main campus of Mass General in 1991.

Today, our surgeons, physician-scientists and physicists continue to investigate and invent next-generation radiation therapies to improve care for our patients.