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The distinguishing feature and current technique progress of tumor treatment with heavy-ion beams is introduced in the paper. Additional superiority to tumor treatment from a radioactive ion beam (RIB) is emphatically discussed. The experimental research of the radioactive 9C-ion beams aimed at tumor treatment at Heavy Ion Medical Accelerator in Chiba (HIMAC), National Institute of Radiological Sciences (NIRS), Japan is described in detail, including production of the beams, optimization of parameters, distribution of depth dose, survival effect of cell and comparison of RBE between 9C- and 12C-beams. Results show that under 40 mm thick Beryllium target and 10 mm thick aluminum degrader at full (5%) momentum acceptance, the production rate and purity of the produced 9C-beams are 9.07⊗10-6 and 82.88% respectively with the primary 12C-beams of 430 MeV/u and 1.8⊗109 pps. A uniform irradiation field with homogeneity up to 89.6% inside central area 10 mm in diameter is obtained by using spot scanning. In this case, the dose rate at the entrance is 0.5 Gy/h. In survival experiment of cells, the average relative biological effectiveness (RBE) of 9C-beams is 5.28 and 2.93 for 12C-beams in the region around Bragg peak. The RBE of 9C-beams is 1.8 times higher than that of 12C-beams. It indicates that cell-killing efficiency of 9C-beams is stronger than that of 12C-beams. 9C-beams are more efficacious for tumor treatment than 12C-beams. [ABSTRACT FROM AUTHOR]

By using the radioactive nuclear beam with relativistic high energy of short-lived positron emitting nuclei, such as 10C and 11C, a verification system for the precise radiotherapy has been developed. It is possible to determine the precise particle range and the three-dimensional irradiated area in the human body by a positron camera detector and a positron emission tomography system, respectively. The biological and chemical process of the metabolism is an important parameter for the precise measurement. The biological lifetimes of the 10C and 11C injected into the rabbit’s organs have been observed for the study of metabolism. The microscopic process around the cell is also of interest in the study of biological effectiveness. The observation of the difference between radiological effectiveness of 9C and that of 12C is in progress. [ABSTRACT FROM AUTHOR]