Abstract
This study was performed to determine the biological effect of carbon beams on 13 human tumor cells, in comparison with 200 KVp X-rays. Carbon beams were generated by the Riken Ring Cyclotron. The RBE (relative biological effectiveness) values were distributed from 1.46 to 2.20 for LET of 20 keV/μm, and 2.29-3.54 for 80 keV/μm. The RBEs were increased in all cell lines as the LET of carbon beams was increased from 20 to 80 keV/μm. There was no significant difference in radiosensitivity between cells from adenocarcinoma and those from squamous cell carcinoma. The relationship between the radiosensitivity of cells to X-rays and RBE was analyzed, but no significant correlation was suggested. Several survival curves of 20-40 keV/μm carbon beam irradiation showed the initial shoulders and the recovery ratios between two split doses were determined. Recovery was observed for LET of 20 keV/μm but not for that of 40 keV/μm. Furthermore, recovery ratios were 1.0-1.8, smaller than those for X-rays (1.5-2.4).
Original language | English |
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Pages (from-to) | 669-673 |
Number of pages | 5 |
Journal | Nippon Acta Radiologica |
Volume | 56 |
Issue number | 9 |
Publication status | Published - 1996 Aug |
Keywords
- Carbon beam
- Human tumor cells
- Linear energy transfer
- Relative biological effectiveness
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Oncology