Care with radiosensitizers

In current radiotherapy trials with the oxygen-mimetic radiosensitizing drugs, which are expected to overcome the potential problem of resistant hypoxic tumour cells, no allowance is being made for sensitization of normal tissue. These new agents are competing with hyperbaric oxygen (HBO) for providing therapeutic benefit, and sensitization by HBO was observed in the skin (van den Brenk et al., 1965), in laryngeal cartilage (Churchill-Davidson, 1968; Henk et al., 1977) and in the neuraxis (Coy and Dolman, 1971). Subsequently, a 10% reduction in dose was estimated as necessary with those HBO treatments of advanced head and neck cancer where laryngeal cartilage was irradiated (Henk and Smith, 1977).