Yamagata University Hospital

Heavy Ion Cancer Therapy

In 2021, heavy ion cancer therapy begins with a world-leading technology!

Yamagata University Hospital has estabtished a heavy ion cancer therapy center, with treatment starting in 2021.

About heavy ion cancer therapy

In recent years, cancer therapy has emphasized the quality of life of patients after treatment, and in order to match the patients' values, therapy requires skillful combination of surgery, chemotherapy, and radiotherapy, known as the three major treatments. Since radiotherapy devices have made rapid advances in performance and function during the past 10 years or so, complete cures are possible with radiotherapy alone for some types of cancer.

Heavy ion cancer therapy, a type of external beam radiotherapy, combines Japan's excellent cancer care with state-of-the-art science and technology. Instead of X-rays, a kind of electromagnetic radiation that has been widely used so far, a carbon ion beam accelerated up to 70% of the speed of light is used. In this treatment, the tumor is precisely targeted from outside the body, offering the following advantages.


  1. Since carbon ion beams have excellent physical properties enabling to concentrate radiation damage intensively on the cancer site, the side effects to normal tissues are smaller compared with X-rays.
  2. Carbon ions are biologically more effective in killing cancer cells, so they have greater therapeutic effect even against cancers that are resistant to X-rays.
  3. Since the carbon ion dose is highly concentrated and the radiation dose of a single fraction of treatment can be higher, the treatment period is shorter than that of X-rays, reducing the time spent in hospital, with consequently less interruption of normal life.

Example of prostate cancer


With X-rays, a high dose (in the order red-green-blue) extends outside the tumor (the part enclosed by yellow lines).
*With the scanning irradiation used at Yamagata University Hospital, the dose distribution can be concentrated further.

The advantages of heavy ion cancer therapy

  1. Short-term treatment is possible
    • Radiotherapy is completed in half the time of other therapy
    • One or two times for lung cancer and liver cancer
    • 12 to 16 times with prostate cancer and the like
    • Overall average 12 times / 3 weeks
  2. Effective for cancer where surgery is difficult
    • Cranial base, head and neck, pelvic area, etc.
  3. Effective for radiation-resistant cancer
    • Sarcoma, malignant melanoma, adenocarcinoma etc.

Diseases suited to heavy ion cancer therapy

  • Head and neck tumors
  • Pulmonary and mediastinal tumors
  • Gastrointestinal tumors (esophagus, recurrent colorectal cancer inside the pelvis)
  • Liver, pancreatic tumor
  • Urologic tumors (prostate, kidney)
  • G gynecologic tumors (locally advanced uterine cervical cancer, locally advanced cervical endometrial cancer, malignant melanoma of the gynecologic area)
  • Metastatic tumors (llung, liver, lymph nodes )
  • Bone and soft tissue tumors

The features of the Yamagata model

The heavy ion cancer therapy equipment at Yamagata University Hospital can deliver the heavy ion beam from every angle using a superconducting rotating-gantry. Compared to conventional fixed direction equipment, it forces less physical burden on the patient and enables more accurate treatment for the affected area.

In addition, the heavy ion beam treatment facility is designed as the world's first facility directly accessible from/to a general hospital via a connecting bridge. The overall system is integrated in a space-saving cube-shaped building. Since it can make use of the functions and infrastructure of the general hospital, it's possible to provide heavy ion radiotherapy safely and smoothly for very elderly patients and patients with pre-existing conditions hitherto difficult to treat.

Also, to enable patients to receive treatment with peace of mind, we offer fully private waiting rooms. This is the first instance where this new concept has been applied to particle therapy facilities in Japan.



The features of the Yamagata model

  • Direct access from/to a general hospital (World's first)
  • Rotating gantry using superconducting technology (The 3rd in the world)
  • Significantly reduced installed area (Smallest in the world)
  • Improved energy saving functions (Approximately half that of older models)
  • 3D pencil beam scanning (The 4th in Japan)
  • Regional cooperation among hospitals in Tohoku using a medical IT network (The first in Japan)