Microdosimetric measurements and estimation of human cell survival for heavy-ion beams.
The microdosimetric spectra for high-energy beams of photons and proton, helium, carbon, neon, silicon and iron ions (LET = 0.5-880 keV/microm) were measured with a spherical-walled tissue-equivalent proportional counter at various depths in a plastic phantom. Survival curves for human tumor cells were also obtained under the same conditions. Then the survival curves were compared with those estimated by a microdosimetric model based on the spectra and the biological parameters for each cell line. The estimated alpha terms of the liner-quadratic model with a fixed beta value reproduced the experimental results for cell irradiation for ion beams with LETs of less than 450 keV/microm, except in the region near the distal peak.
Kase
Yuki
Y
Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan. y_kase@nirs.go.jp
Kanai
Tatsuaki
T
Matsumoto
Yoshitaka
Y
Furusawa
Yoshiya
Y
Okamoto
Hiroyuki
H
Asaba
Toru
T
Sakama
Makoto
M
Shinoda
Hiroshi
H
D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005347:Fibroblasts / Q000166:cytology* / Q000528:radiation effects*; D020450:Heavy Ions; D006801:Humans; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012468:Salivary Gland Neoplasms / Q000473:pathology*