What is Proton Therapy?

Proton therapy is a form of cancer treatment that is currently used in approximately 25 treatment centers in the U.S. and approximately 60 centers worldwide.  Currently, there are several other centers under development in the U.S. and the world.

Proton therapy is a highly advanced form of radiation therapy that can provide cancer patients with an increased likelihood of superior clinical outcomes and fewer side effects or complications when compared to surgery, chemotherapy and conventional radiation (photon/X-ray) therapy alternatives. Proton therapy uses accelerated particles (protons) to precisely treat cancerous tumors throughout the body. Proton therapy is more precise than conventional forms of radiation treatment, delivering an exact, high dose of radiation to a tumor site while sparing surrounding healthy tissue and organs from damage.

Proton therapy is frequently used in the care of children diagnosed with cancer, as well as in adults who have small, well-defined tumors in organs that effect the nervous system, respiratory system, prostate, digestive system, arteriovenous malformation, central nervous system, head/neck areas and eye/orbit area.  According to the National Cancer Institute, research continues into its efficacy in additional cancers.

Medicare and most private healthcare insurance payors have established reimbursement rates for proton therapy treatment. Proton therapy is a non-invasive treatment performed on an outpatient basis. Depending on cancer type, patients will typically receive an average of 31 treatments, or fractions, during a 5-6 week period. Each treatment is expected to require an appointment of approximately 20-25 minutes in length, after which the patient is expected to be able to carry on with their daily activities.

What is the Bragg Peak?

Proton therapy is different than traditional radiation therapy in the way the energy is delivered to the patient. With proton therapy, very little dose is delivered along the path prior to reaching the target. Instead protons deliver most of their energy at a prescribed, programmable distance inside the body, known as the Bragg Peak.

This type of treatment delivery differs from traditional radiation therapy, which deposits most of its energy near the surface of the body. With precisely targeted proton therapy, clinicians can are better able to:

  • Treat tumors surrounded by critical organs while sparing healthy tissues
  • Reduce side effects common in traditional radiation therapy
proton bragg peak


What is Pencil Beam Scanning (PBS)?

GPTC will have Varian's ProBeam® system which uses pencil beam scanning. Clinicians can therefore treat larger and more complex tumors, while at the same time sparing more healthy tissue. Only pencil beam scanning, and not passive scattering delivery of proton therapy, can deliver intensity-modulated proton therapy (IMPT). The use of proton therapy—partnered with the accuracy of pencil beam scanning—offers optimal tumor control.

Cancer Market Overview

The American Cancer Society estimates that there will be approximately 1,685,210 new cancer cases in the U.S. in 2016 (841,390 cases in males and 843,820 cases in females). Of which, about 60%, or 1,011,126 cases, will be treated with radiation therapy.  GPTC believes that approximately 20% of all patients treated with radiation therapy, or more than 202,225 patients in 2016, will be candidates for proton therapy treatment.

According to the U.S. Census Bureau, the number of people over 65 years of age in the U.S. alone is expected to increase by 36% to 47,700,000 in 2015 from 35,000,000 in 2000. As a result of the aforementioned, the National Cancer Institute estimates that the number of new cancer cases diagnosed annually in the U.S. could reach 3,000,000 by 2050.

Proton therapy is a form of radiation therapy. Proton therapy uses accelerated particles (protons) to treat cancerous tumors throughout the body. Proton therapy is more precise than conventional forms of radiation treatment, delivering an exact, high dose of radiation to a tumor site while reducing the potential for damaging impacts to surrounding healthy tissue and organs. In contrast, the efficacy of conventional radiation (photon/X-ray) therapy, which is used in approximately 60% of all cancer cases, is often limited because of its inability to deliver a sufficient “dose” of radiation into a cancerous tumor to destroy it while simultaneously avoiding damage to the surrounding healthy tissue. Consequently, proton therapy can offer an alternative in treating many cancers with a potential for decreased incidence of complications.