Proton Therapy

What is proton therapy

Proton therapy is an advanced radiation treatment that precisely targets tumors, with the goal of minimizing radiation to healthy tissue and improving the lives of patients while they’re fighting cancer and after. Proton therapy deposits the greatest amount of radiation right into the tumor and then stops, allowing patients to receive high doses to the tumor, with minimal dose to nearby healthy tissue. This more targeted form of radiation is especially useful for childhood cancers, where the impact of excess, harmful radiation can cause long-term damage. Additionally, protons are an effective treatment against many solid tumors including cancers of the brain, central nervous system, gastrointestinal tract, head and neck, left breast, lung, and prostate, as well as sarcomas.

Research shows proton therapy can minimize short- and long-term side effects, reduce the occurrence of secondary tumors, and improve patients’ quality of life. When external beam radiation is called for, proton therapy can be an effective option for treating many solid tumors.

Gastrointestinal Refers to the stomach and intestines. Also called GI. Side effects A problem that occurs when treatment affects healthy tissues or organs. Some side effects of cancer treatment are nausea, vomiting, fatigue, pain, decreased blood cell counts, hair loss and mouth sores.

Dr. Rengan explains proton therapy

Pencil Beam Scanning

For many patients, innovative pencil beam scanning (PBS) is a great option. PBS "paints" the entire tumor with multiple very thin, very precise beams of protons that are accurate within millimeters, and can further reduce the amount of radiation to healthy tissue.

A goal of sparing healthy tissue to help speed recovery

Proton therapy is a powerful treatment for cancer and a highly effective alternative to standard X-ray radiation therapy. Due to improved dose distribution with proton therapy, doctors can better conform radiation to the tumor site, which means less healthy tissue is exposed to radiation, and which in turn is expected to result in fewer short- and long-term side effects.

X-ray therapy for a brain tumor vs. proton therapy for a brain tumor

With X-ray (conventional) radiation therapy, more healthy tissue is exposed to radiation. With treatments utilizing proton beams, less healthy tissue is exposed to radiation (colored area indicates radiation exposure; gray/white area indicates no radiation exposure).

Radiation therapy The use of high-energy radiation from X-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. The use of high-energy radiation from x-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy or brachytherapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Side effects A problem that occurs when treatment affects healthy tissues or organs. Some side effects of cancer treatment are nausea, vomiting, fatigue, pain, decreased blood cell counts, hair loss and mouth sores.

X-ray therapy for a brain tumor vs. proton therapy for a brain tumor

Children benefit from reduced radiation exposure

Since proton therapy is targeted, it can be particularly effective in treating children, who are more sensitive to the effects of radiation. The precision of protons means children have a reduced chance of radiation side effects such as growth and developmental problems, as well as secondary tumors later in life. The center has radiation oncologists who specializes in proton therapy treatment for children.

Fast, painless, noninvasive

Treatments are safe, noninvasive, and painless for most patients. Treatments do not require an overnight stay in the hospital. Treatments are usually given five days a week, for a period of one to nine weeks. The total number of treatments needed depends on the location and size of the tumor. The actual treatment time is about one minute but total daily treatment sessions typically range from 15 to 60 minutes, due to the time spent positioning the patient for this precise treatment. Patients come to the center every day for a short period of time, but can then go about their usual routine.

Researched and perfected for more than 60 years

As of 2018, over 170,000 people worldwide have received proton therapy at centers in Europe, Asia and the United States. It was first used to treat patients in 1955 in a research setting, but its use was limited because imaging techniques at the time could not accurately pinpoint tumors. The FDA approved proton therapy in 1988, following advances in imaging technology, such as CT, MRI and PET scans. The first hospital-based treatment center opened in Loma Linda, California in 1990. SCCA Proton Therapy opened in 2013.

Highlights:

A goal of less radiation delivered to healthy tissue and critical structures adjacent to the treatment area
Ability to deposit a larger dose in the targeted area if needed
Fewer side effects and faster recovery due to precise delivery of radiation to target area
Precise application is ideal for a wide range of tumors
Precise targeting gives proton beam therapy a significant advantage over standard radiation therapy when treating tumors near vital organs

If you have a solid tumor near a vital organ, or a recurrent tumor, you are a prime candidate for proton therapy.

Patient guide to proton therapy

Computed tomography A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are used to create three-dimensional (3-D) views of tissues and organs. A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create three-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. This scan may be used to help diagnose disease, plan treatment or find out how well treatment is working. Imaging In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as X-rays (high-energy radiation), ultrasound (high-energy sound waves) and radio waves. Magnetic resonance imaging A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or X-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints and the inside of bones. Radiation oncologist A physician who has special training in using radiation to treat cancer. Radiation therapy The use of high-energy radiation from X-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. The use of high-energy radiation from x-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy or brachytherapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Side effects A problem that occurs when treatment affects healthy tissues or organs. Some side effects of cancer treatment are nausea, vomiting, fatigue, pain, decreased blood cell counts, hair loss and mouth sores.

History of Proton Therapy

1895
German physicist W.C. Roentgen discovers X-rays, making detection of tumors in the body much easier and non-invasive. Roentgen later wins the Nobel Prize in Physics for this discovery.

1919
British physicist Ernest Rutherford demonstrates the existence of protons (elementary particles found in atoms).

1931
American physicist Ernest O. Lawrence invents the cyclotron, a machine used in proton therapy, which accelerates charged particles to high energy levels.

1937
The first clinical use of X-ray radiation therapy is carried out for the treatment of a patient with leukemia at the University of California at Berkeley. Congress passes the National Cancer Institute Act that authorizes annual funding for cancer research in the United States.

1946
American physicist Robert Wilson publishes a study that suggests protons could be used to treat cancer because they are capable of delivering an increased dose of radiation to a tumor while simultaneously decreasing radiation exposure to surrounding healthy tissue.

1948
The first proton therapy experiments are conducted at the University of California at Berkeley. Tumors are effectively removed from the chest and lungs of animals.

1954
The University of California at Berkeley treats the first human patient with protons. Patients are treated with protons at other research institutions, including Harvard University in Boston.

1980s
Advances in imaging technology, including CT, MRI and PET scans, help researchers to better diagnose and see tumors, making proton therapy, which requires identifying the precise location of a tumor, a more practical treatment option.

1988
The FDA approves proton therapy as a cancer treatment option.

1990
The first hospital-based proton treatment center in the United States is built at Loma Linda University Medical Center in Loma Linda, Calif.

2001
The first patient is treated at Harvard/Massachusetts General Hospital’s Francis H. Burr Proton Therapy Center in Boston, the second hospital-based proton treatment center in the United States.

2003
The Midwest Proton Radiotherapy Institute (MPRI), the third proton treatment center in the United States, opens in Bloomington, Ind.

2005-2010
Seven more institutions open proton therapy centers in the United States.

2013
On March 8, 2013, Seattle Cancer Care Alliance Proton Therapy opens in Seattle. It’s the first proton center in the Northwest and the only one within a 1000-mile radius. Seattle Cancer Care Alliance is a world-class cancer treatment center that unites doctors from Fred Hutchinson Cancer Research Center, UW Medicine and Seattle Children's.

Computed tomography A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are used to create three-dimensional (3-D) views of tissues and organs. A procedure that uses a computer linked to an X-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create three-dimensional (3-D) views of tissues and organs. A dye may be injected into a vein or swallowed to help the tissues and organs show up more clearly. This scan may be used to help diagnose disease, plan treatment or find out how well treatment is working. Imaging In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as X-rays (high-energy radiation), ultrasound (high-energy sound waves) and radio waves. Magnetic resonance imaging A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or X-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints and the inside of bones. Radiation therapy The use of high-energy radiation from X-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. The use of high-energy radiation from x-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy or brachytherapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Radiation therapy The use of high-energy radiation from X-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. The use of high-energy radiation from x-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy or brachytherapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body.

History of Proton Therapy

Learn more about the evolution of proton therapy from the early days of conventional radiation in medicine through the opening of the SCCA Proton Therapy Center.

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