Proton Beam Therapy

What is proton therapy?

Proton therapy is a newer type of radiation therapy that uses high-powered energy to treat cancer with positively charged particles called protons. Proton therapy has shown to cause fewer side effects than traditional radiation due to the ability to better control where the radiation beam delivers its energy. This type of radiation is often used when tumors are close to vital organs.

Treatment Overview

How does proton therapy work?

Proton beam therapy is a type of particle beam radiation therapy. It does not use rays of radiation, like gamma rays or X-rays. Instead, it uses particles, like protons or neutrons.

Proton beam therapy is the most widely used type of particle beam therapy. It is useful in treating tumors or lesions that are small or have an irregular shape. The radiation dose can be more closely controlled with these systems. The proton beam can be controlled so that it places its energy almost completely in the tumor or lesion being treated. Other forms of radiation lose energy as they enter body tissues on their way to the tissue under treatment. The proton beam's depth can be controlled precisely. So there is less damage to normal tissues around the area being treated.

Proton beam therapy may be used for radiosurgery procedures. Or it can be used when several smaller doses of radiation are given over a certain period of time (fractionated radiotherapy). There are only a few facilities in North America that provide proton beam therapy.

What is the difference between proton beam therapy and photon beam therapy?

Proton therapy and photon therapy are the two main types of radiation used to treat cancer patients. Proton beams use highly charged particles to deliver a prescribed dose of radiation to a specific target. Protons can deposit their full energy at a well-defined point, allowing for less radiation dose to the surrounding tissues. Photon beams, on the other hand, deposit small amounts of radiation on its way to and from the targeted area.

Benefits and Risks

What are the benefits of proton beam therapy?

The main benefit of proton beam therapy is its ability to directly target lesions. The healthy cells surrounding the area are less affected compared to traditional types of radiation treatments. It’s also a good option when tumors are close to areas that are sensitive, such as on the brain or spine. It also minimizes risks to vital organs. 

What are the risks associated with proton beam therapy?

The risks of proton beam therapy are still being studied. The effectiveness varies depending on the type of cancer, location and progression of the tumor, and your overall health.

Side Effects

What are the side effects of proton beam therapy?

Proton beam therapy side effects are similar to side effects of any other cancer treatment.

  • Fatigue
  • Hair loss at the site of therapy
  • Sore or reddening of the skin at the site of therapy

Management & Support

After each treatment, you may have tiredness (fatigue), sensitive skin at the radiation site, and emotional distress. Plan for extra rest and try to eat a healthy, well-balanced diet. Limit how much sun you get on sensitive skin areas. Use only lotions approved by your healthcare team. Your treatment team will have information on how to best manage physical side effects. You can ask for a referral to a mental health specialist to help cope with the emotions surrounding your diagnosis and treatment. Your treatment team has resources to help you.

The radiation oncologist will watch your progress and how the cancer responds to each treatment. They may change the radiation dose, number of treatments, or the length of treatment.

Once all treatments in your schedule are done, your healthcare team will let you know the follow-up schedule. You will need to return for follow-up assessments. These often include imaging tests and blood tests. These tests will tell them if the cancer is no longer present or if you need more treatment. You will need to make regular follow-up visits if the tumor is gone.

Treatment doesn’t end with physical cancer treatments. You’ll have access to many oncology services which can support your treatment and healing of mind, body and spirit.