How is Proton Therapy Different?
Similar to conventional high energy X-rays, proton therapy is an external-beam
radiation therapy technique. The difference is that protons are heavy charged particles that deposit radiation dose in a very targeted manner. When protons enter the body, they leave a small amount of energy along their path as they interact with the tissue.   When they reach a specific depth, protons deposit a large focused amount of energy and then stop, leaving no energy beyond that depth. This is what William Henry Bragg discovered in 1904 and what is now referred to as the Bragg Peak. The depth of the Bragg Peak is precisely controlled by changing the energy of the protons, thus allowing physicians to precisely tailor the proton dose to the specific depth and shape of the tumor while greatly reducing the dose to surrounding healthy tissue. The advantages of proton therapy over conventional radiotherapy are important for pediatric tumors and in areas of the body with critical adjacent structures such as the eye, brain, base of the skull, spine, and prostate.

Because of its dose-targeting advantages, proton therapy has long been recognized as a superior cancer treatment modality. Dr. Robert Wilson first proposed the use of protons for cancer treatment in 1946 and shortly after, the first clinical treatments were performed at the Berkeley Radiation Laboratory in the mid 1950s and then at the Harvard Cyclotron Laboratory in the early 1960s.  However, the cost, size, and complexity of the proton therapy systems have greatly limited their widespread clinical use. Mevion Medical Systems eliminates these obstacles with the introduction of the MEVION S250, a revolutionary proton therapy system that combines a patented gantry-mounted proton source with a highly integrated, image-based workflow, making proton therapy a practical clinical reality.

Treatment sites where proton therapy is used:

Pediatric Tumors
Head and Neck

The MEVION S250 Proton Therapy System is USFDA 510(k) cleared and complies with MDD/CE requirements.