[Neutron Therapy - From Radiobiological Expectation To Clinical Reality]

The radiobiological data presently available indicate that high linear energy transfer (LET) radiation could bring a benefit in the treatment of some types of rumours (typically, slowly-growing, well-differentiated tumours). Radiobiology also suggests some mechanisms through which this benefit could be achieved: hypoxic gain factor, kinetic gain factor, etc. Among the high-LET radiations, fast neutrons are the least expensive and the most widely used in therapy. Two main difficulties are encountered when reviewing the clinical results of fast neutron therapy: patient selection and physical selectivity. Despite these caveats, the currently available clinical results indicate that neutrontherapy is an alternative treatment - if not the best choice - for well-differentiated, slowly-growing rumours, such as salivary gland rumours and prostatic adenocarcinomas.