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Director Greetings

Cancer is currently the leading cause of death in many countries and medical technology has been rapidly progressing. There are three pillars of cancer treatment including surgery, chemotherapy and radiotherapy. Among them, radiotherapy would be a highly effective method in terms of high tumor control and functional preservation of the organs from which cancer developed. Moreover, as compare with other modalities, radiotherapy can be applied to a wider range of tumors with acceptable toxicities. In this respect, This is particularly true when charged particle beams are employed .


Among the charged particle therapy, carbon-ion radiotherapy is the treatment of no pain with minor side effects. It has an advantage that, as compared with other modalities, treatment can be completed in much shorter time and less fractionations. Many of the patients can receive treatment as an outpatient basis and quickly come back to work or normal life. In selected cases, hospital admission is not required and it takes only few days to complete the entire treatment, the patients can continue to work with carrying out daily activities almost the same as before.


In an effort to assist cancer patients, we have started a consultation clinic, “Particle Radiotherapy Clinic”, providing a second medical opinion to the patients who are seeking medical advice and are particularly interested in charged particle therapy. This therapy is a form of external beam radiotherapy using protons and carbon-ions, which in recent years have been widely accepted in general practice. For more detail about this treatment, please see the note below.*


At the clinic, your data will be reviewed and you will have our second medical opinion service by our radiation oncologists, who are all professionals in carbon-ion radiotherapy and have wide knowledge about cancer treatment. They will help you with your queries whether or not you are an appropriate candidate for carbon-ion radiotherapy as well as such queries:


What does your diagnosis mean?
Is the proposed treatment correct?
Is there an alternative treatment that would be better for you?

If you are NOT a candidate for carbon-ion radiotherapy and if you wish, you will be referred to other doctors or hospitals for seeking other treatment.


It is also possible in our clinic, to provide diagnostic services such as CT, MRI, PET-CT, and biochemical examinations. We can therefore accept your visit that is only for follow-up examinations or medical advice


The uniqueness of our clinic is that, once the patient is judged to be suitable for carbon-ion radiotherapy, our doctors will proceed to next steps for carbon-ion radiotherapy for you.


We are confident that we can offer you the most appropriate second opinion for your condition. Please feel free to contact us.

Hirohiko Tsujii M. D.


The clinical benefit of charged particle therapy results from the manner in which protons and carbon-ions lose their energy in tissue. They can deposit most of their energy at the tumor site by exhibiting a so-called Bragg-peak with sparing normal tissues surrounding the tumor. In addition, carbon-ions being heavier than protons offer higher biological effect, which increases with depth reaching the maximum at the tumor site. This is an ideal property from the standpoint of cancer therapy. Carbon-ions are applicable to many types of cancers that are resistant to conventional radiotherapy or hard to treat with surgery.


At present, there are seven facilities in operation for carbon-ion radiotherapy in the world. Four of them are facilities in Japan, including Research Center for Charged Particle Therapy at the National Institute of Radiological Sciences (NIRS), Gunma University Heavy Ion Medical Center (GHMC), Hyogo Ion Beam Medical Center (HIBMC), and Saga Heavy Ion Medical Accelerator in Tosu (SAGA HIMAT). Kanagawa Cancer Center is constructing the 5th facility and will start their service soon.