Chemotherapy pp 187-206 | Cite as

Biological Basis of Radiosensitization by Hypoxic-Cell Radiosensitizers

  • G. E. Adams
  • J. Denekamp
  • J. E. Fowler


Radiosensitizing drugs can only be clinically useful if they give a greater increase in sensitivity to radiation in the tumour than in normal tissues. This differential may be based on differences in the proliferation characteristics or on other known differences between normal and tumour cells, such as their oxygen status. The degree of oxygenation profoundly influences the radiosensitivity of all cells: hypoxic cells occur in most animal tumours and can be more effectively killed if their hypoxic protection is overcome e.g. with hyperbaric oxygen, high LET radiation or with electron affinic chemical radiosensitizers. This latter group of drugs includes nitroimidazoles which have recently been shown to mimic oxygen in its sensitizing ability. The drugs can diffuse to hypoxic tumour cells because, unlike oxygen, they are not rapidly metabolised by respiring cells.


Fast Neutron Hyperbaric Oxygen Local Tumour Control Hypoxic Cell Enhancement Ratio 
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Copyright information

© Plenum Press, New York 1976

Authors and Affiliations

  • G. E. Adams
    • 1
  • J. Denekamp
    • 1
  • J. E. Fowler
    • 1
  1. 1.Gray Laboratory of the Cancer Research CampaignMount Vernon HospitalNorthwoodEngland

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