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.
British physicist Ernest Rutherford demonstrates the existence of protons (elementary particles found in atoms).
American physicist Ernest O. Lawrence invents the cyclotron, a machine used in proton therapy, which accelerates charged particles to high energy levels.
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.
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.
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.
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.
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.
The FDA approves proton therapy as a cancer treatment option.
The first hospital-based proton treatment center in the United States is built at Loma Linda University Medical Center in Loma Linda, Calif.
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.
The Midwest Proton Radiotherapy Institute (MPRI), the third proton treatment center in the United States, opens in Bloomington, Ind.
Seven more institutions open proton therapy centers in the United States.
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.