• What is heavy ion radiotherapy?
  • Introduction of the related facilities and counseling clinics
  • Present status and actual results
  • Papers and various data
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What is heavy ion radiotherapy?

What are heavy ion beams?
In Japan, heavy ion radiotherapy is performed using carbon ion beams

Heavy ion beams = Carbon ion beams

In a broad sense, heavy ion beams mean beams of any particles that are heavier than electrons.
In Japanese heavy ion radiotherapy, the term "heavy ion beam" indicates a nucleus (heavy ion) beam of any atom that is heavier than helium (He), or has an atomic number larger than that of helium. In Japan, carbon ion beams have been used as heavy ion beams for cancer therapy for almost 20 years. At present, therefore, "heavy ion beams" indicates "carbon ion beams." In cancer therapy, carbon nuclei, which are 12 times as heavy as protons, are accelerated to approximately 70% of light speed, and then irradiated to the target.

* The usage of the term "ion beam" is not the same all over the world. In some parts of the EU, treatments with ion beams in general may be called "hadron therapy," and beams using carbon ions and any lighter ions are called "light ion beams." In Japan, however, the term "heavy ion radiotherapy" is used synonymously with carbon ion radiotherapy, as it is on this website.

What are heavy ion beams?
Radiations for cancer therapy
Types of radiation Conventional therapeutic radiations Heavy particle beams
Electromagnetic waves
Uncharged particle beams
X-rays, gamma rays Neutron beams
  ・Thermal neutron beams
  ・Fast neutron beams
Charged particle beams Electron beams Heavy charged particle beams
  ・Negative pion beams
  ・Proton beams
  ・Heavy ion beams