Radiobiology of neutrons

Journal Article · Wed Dec 01 00:00:00 EST 1982 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(82)90553-3· OSTI ID:5403705

Barendsen, G W

Tumor responses depend on a number of factors, of which the intrinsic radiosensitivity of the cells and their oxygenation condition can be considered as most important. Variations of the sensitivity in the cell cycle and differences between resting and proliferating cells are considered to play a smaller part. Large differences in intrinsic cellular sensitivity and in RBE values of fast neutrons have been observed for impairment of the clonogenic capacity of cells in culture and in experimental tumors. For most of the treatments commonly applied in radiotherapy, doses per fraction are smaller than 5 Gy of photons and 1.5 Gy of neutrons. However, a direct correlation between cellular sensitivity and the magnitude of RBE values has not been establised. With X rays, more sparing of normal tissues is obtained than for these tumors, and the application of neutrons is not expected to provide an advantage in this respect. The presence of hypoxic cells in experimental tumors has been well established. It has been observed, however, that for daily fractionated treatments with doses of less than 3 Gy of photons, the influence of hypoxia is much smaller than for single large doses, because of the process of reoxygenation. Nevertheless the low OER of fast neutrons and other high LET radiation might provide an advantage that could improve treatment results. It is suggested that better methods must be developed to predict the responsiveness of tumors in patients to photons, in order to selectively apply high LET radiations only to tumors that are resistant to photons.

• Research Organization: Univ. of Amsterdam, The Netherlands
• OSTI ID: 5403705
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Vol. 8:12
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
FAST NEUTRONS
RADIOBIOLOGY
RBE
ANIMAL CELLS
EXPERIMENTAL NEOPLASMS
OXYGEN ENHANCEMENT RATIO
RADIOTHERAPY
BARYONS
BIOLOGY
ELEMENTARY PARTICLES
FERMIONS
HADRONS
MEDICINE
NEUTRONS
NUCLEAR MEDICINE
NUCLEONS
RADIOLOGY
THERAPY
560151* - Radiation Effects on Animals- Man