Proton Therapy

Cancer Treatment Through Proton Therapy.

In the treatment of cancer, high doses of radiation are used to destroy cancer cells by damaging their DNA.  When the DNA of a cancer cell is destroyed beyond repair, the cell dies and is then eliminated by the body through natural processes.

Proton therapy is an advanced form of radiation treatment that has been used to treat more than 160,000 people worldwide. By 2030, it is estimated that between 300,000 and 600,000 patients will have received proton therapy treatment.

What is proton therapy?

Proton therapy is a type of radiation treatment that is able to target tumors with precision. This enables radiation oncologists to destroy tumors while sparing normal tissue, thereby reducing side effects and improving long-term outcomes for patients.

Proton therapy is particularly effective at treating tumors near sensitive organs, the brain stem, and spinal cord, and in treating pediatric tumors.

How does proton therapy work?

Traditional radiation treatment uses photons to target tumors. Photons deposit energy along the path of the X-ray beam, delivering radiation to the tumor as well as adjacent normal tissue. The exposure of radiation beyond the target is called the exit dose. The exit dose can result in damage to nearby organs and normal tissues and can cause future health issues.

Figure 1: Traditional radiation treatment has a relatively high entrance dose and exit dose. Proton therapy has a lower entrance dose and no exit dose.

proton beam no exit dose

Proton therapy is different because of the Bragg peak phenomenon. Unlike photons, protons deposit the majority of their energy at a single point, the Bragg peak. Proton therapy technology allows doctors to control the location of the Bragg peak and, therefore, the deposition of radiation. Because the proton beam can be conformed to the shape and depth of the tumor, the exit dose is eliminated, sparing surrounding organs and normal tissue from radiation exposure. Because of this, patients can receive higher doses, increasing the effectiveness of treatment.

Figure 2: Because of the Bragg peak phenomenon, the exit dose is eliminated, sparing normal tissue from radiation exposure.

Bragg Peak

Proton therapy treatment

There are three types of proton-beam delivery methods: passive scattering, uniform scanning, and pencil beam scanning. When identifying treatment options and developing treatment plans, it is important to consider the method of proton-beam delivery.

Pencil beam scanning is the most precise form of proton therapy. Using an electronically guided scanning system and magnets, pencil beam scanning delivers proton therapy treatment via a proton beam that is just millimeters wide. With pencil beam scanning, beam position and depth are able to be controlled, allowing for highly precise deposition of radiation to be delivered in all three dimensions of the tumor.

Advantages of proton therapy treatment

Advantages of proton therapy treatment include:1, 2

  • Ability to target tumors with precision allowing treatment in close proximity to critical structures
  • No exit dose, therefore, minimizing radiation exposure to healthy tissues and organs
  • Ability to target tumors with high dose
  • Fewer short-term side effects
  • Reduces the risk of long-term side effects, including the development of secondary malignant tumors
  • Faster recovery

Proton therapy technology

Identifying the best proton therapy technology for your hospital or clinic is a big decision.

The Radiance 330® Proton Therapy System has been described as the future of proton therapy. Radiance 330® delivers vanguard proton therapy treatment with the precision of pencil beam scanning and the power of integrated imaging.  Designed to increase accessibility, Radiance 330® is compact, modular, and scalable. And with low capital and operating costs, Radiance 330® is affordable.



1 W P Levin, H Kooy, J S Loeffler, T F DeLaney. “Proton Beam Therapy.”
Br J Cancer. 2005 Oct 17; 93(8): 849–854. Published online 2005 Sep 27. doi: 10.1038/sj.bjc.6602754

2 University of Pennsylvania School of Medicine. “Studies point to clinical advantages of proton therapy: Studies demonstrated lower toxicities, positive survival outcomes for lung, pancreatic and spine cancers.” ScienceDaily. Published online 2015. Oct 19.