Dose-effect relations for tumour control and complication rate after fast neutron therapy for pelvic tumours

The effects of fast neutrons and high-energy photons were analysed for tumour control and skin and bowel damage after treatment of bladder and rectal cancers. A combination of statistical models was used for this analysis. A steep dose-effect curve was found for local tumour control as well as for the risk of complications. Some estimates were made of RBE values for control of bladder tumour and for normal-tissue damage. The implication of these data for neutron therapy is discussed.