| RRC ID |
41388
|
| Author |
Ando K, Furusawa Y, Suzuki M, Nojima K, Majima H, Koike S, Aoki M, Shimizu W, Futami Y, Ogino T, Murayama S, Ikeda H.
|
| Title |
Relative biological effectiveness of the 235 MeV proton beams at the National Cancer Center Hospital East.
|
| Journal |
J Radiat Res
|
| Abstract |
A therapy-dedicated cyclotron was installed in the National Cancer Center Hospital East (NCCHE) at Kashiwa in 1997. Prior to the start of clinical use, we investigated the biological effectiveness of therapeutic proton beams for cell lethality. The proton beams accelerated up to 235 MeV were horizontally extracted from the cyclotron, and scattered by a bar-ridge filter to produce a Spread-Out-Bragg-Peak (SOBP) of 10-cm width. The biological systems used here were mouse intestinal crypt cells and three in vitro cell lines, including SCC61 human squamous cell carcinoma, NB1RGB human fibroblasts and V79 Chinese hamster cells. The dose responses after irradiation at either the entrance plateau or the middle portion of SOBP were compared with those after linac 6 MV X-ray irradiation. The fit of a linear quadratic model to survival curves showed that proton irradiation increased the alpha value of SCC61 and the beta value of V79 cells with a least change for alpha/beta ratio of NB1RGB cells. The isoeffect dose that reduces either cell survivals to 10% or mouse jejunum crypts to 10 per circumference was termed D10. The relative biological effectiveness (RBE) of protons obtained by comparing the D10 values between protons and X-rays ranged from 0.9 to 1.2. The depth distribution of cell lethality was measured by replating V79 cells after irradiation from a "cell stack chamber" that received a single dose of 7 Gy at the middle position of SOBP. The thus-obtained cell survivals at various depths coincided well with the estimated survivals, but tended to decrease at the distal end of SOBP. We conclude that an RBE of 1.1 would be appropriate for 235 MeV proton beams at the NCCHE.
|
| Volume |
42(1)
|
| Pages |
79-89
|
| Published |
2001-3-1
|
| DOI |
10.1269/jrr.42.79
|
| PMID |
11393892
|
| MeSH |
Animals
Cell Survival / radiation effects
Cells, Cultured
Humans
Intestines / cytology
Intestines / radiation effects*
Mice
Protons*
Radiotherapy Dosage
Relative Biological Effectiveness
|
| IF |
1.95
|
| Times Cited |
55
|
|
WOS Category
|
RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING
BIOLOGY
|
| Resource |
| Human and Animal Cells |
NB1RGB(RCB0222) |
