Clinical neutron dosimetry

The present report is concerned primarily with the determination of absorbed dose in a patient irradiated by beams of fast neutrons. In order to compare the clinical results of fast neutron therapy at different institutions, particularly in clinical trials organized by cooperative groups, it is essential to check and to compare the technical irradiation conditions. Most neutron radiotherapy centers used that report as the main source of information on methodology and basic physical data for neutron dosimetry. However, a number of international neutron dosimetry intercomparisons (e.g., Broerse et al., 1978; ICRU, 1978a) concluded that to reduce differences in quoted absorbed-dose values, it would be necessary to standardize the experimental techniques and that common numerical values of the basic physical parameters should be agreed upon. One of the purpose of this report is to give new recommendations with respect to the values of the basic parameters and experimental techniques employed, based on information now available. 300 refs., 43 figs., 13 tabs