ION BEAM TREATMENT FOR HEAD AND NECK CANCER

Abstract

The ion beam treatment in the Hyogo Ion Beam Medical Center (HIBMC) is carried out with a comprehensive system that consists of an irradiation system, a treatment planning system and a treatment verification system. The treatment verification system consists of a positron emission tomography (PET) camera. As charged particles produce short-lived positron-emitting isotopes in tissues, the treated site can be verified by images taken immediately after irradiation using a PET camera.
A technician sets up an immobilizing device fitted to an individual patient using plastic materials, and takes CT and MRI images of the treatment target site. Treatment planning is carried out using the 3-D treatment planning system. At this time CT and MRI fusion images are used for treatment planning. Before treatment, a rehearsal is done and on the day of treatment, the positioning is performed in the same way as the rehearsal. After positioning, ion beam therapy is started. A respiratory gating system is used for patients with lung or liver cancer.
On April 1, 2001, HIBMC was opened as the world's first facility to provide both proton and carbon-ion radiotherapy. We have treated more than 950 patients with a variety of malignant tumors including skull base, head and neck, lung, liver and prostate tumors. Excellent local control for these tumors has been obtained with minimum side effects. Experience of clinical trial and general practice, showed that radio-resistant tumors in the head and neck region like mucosal malignant melanoma and adenoid cystic carcinoma could be locally controlled with proton beam therapy. In the future we will analyze the difference between two beams for the patient with head and neck cancer.