Chromosome aberration frequencies produced by a 70-MeV proton beam

Journal Article · Wed Aug 01 04:00:00 EDT 1990 · Radiation Research; (USA)

DOI:https://doi.org/10.2307/3577543· OSTI ID:6602581

Matsubara, S; Ohara, H; Hiraoka, T; Koike, S; Ando, K; Yamaguchi, H; Kuwabara, Y; Hoshina, M; Suzuki, S ^[1]

---

1. Tokyo Medical and Dental Univ. (Japan)

The effectiveness of a 70-MeV proton beam in the induction of chromosome aberrations was studied. We employed peripheral lymphocytes and analyzed the frequencies of dicentrics and rings after irradiation at doses ranging from 0.1 to 8.0 Gy at various depths within a Lucite phantom. The frequency of chromosome aberrations after irradiation with an unmodulated proton beam at 5 mm showed a dose-response relationship similar to that of 60Co gamma rays. However, irradiation at greater depths with the spread-out Bragg peak induced higher aberration frequencies at doses lower than those with gamma rays. Furthermore, the distribution curve of chromosome aberration frequencies as a function of depth was found to be slightly different from the physically measured depth-dose curve. With the spread-out Bragg peak the biological effects were more marked at greater depths, resulting in a distribution of relative biological effectiveness values. The results obtained from chromosome aberration analysis may not be related directly to those for the relationship between dose and cell killing. Slight differences in values for relative biological effectiveness due to the change of dose and site of proton beam irradiation may not be important for practical proton beam therapy, but may be important in the prevention of late radiation injuries.

• OSTI ID: 6602581
• Journal Information: Radiation Research; (USA), Journal Name: Radiation Research; (USA) Vol. 123:2; ISSN RAREA; ISSN 0033-7587
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
655003* -- Medical Physics-- Dosimetry
ACCELERATORS
ANIMAL CELLS
BEAMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CELL KILLING
CHROMOSOMAL ABERRATIONS
COBALT 60
COBALT ISOTOPES
CONNECTIVE TISSUE CELLS
DEPTH DOSE DISTRIBUTIONS
DOSE-RESPONSE RELATIONSHIPS
DOSES
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IONIZING RADIATIONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LEUKOCYTES
LINEAR ACCELERATORS
LYMPHOCYTES
MATERIALS
MINUTES LIVING RADIOISOTOPES
MOCKUP
MUTATION FREQUENCY
MUTATIONS
NUCLEI
NUCLEON BEAMS
ODD-ODD NUCLEI
PARTICLE BEAMS
PHANTOMS
PROTON BEAMS
RADIATION DOSE DISTRIBUTIONS
RADIATION DOSES
RADIATIONS
RADIOINDUCTION
RADIOISOTOPES
RBE
SOMATIC CELLS
SPATIAL DOSE DISTRIBUTIONS
STRUCTURAL MODELS
YEARS LIVING RADIOISOT