The use of neutron beam therapy in the management of locally advanced nonresectable radioresistant tumors.

Locally advanced nonresectable radioresistant tumors can often be ablated by external irradiation using high-energy fast neutrons. Long-term remission, with local control rates of 50 to 70 percent, have been reported in a number of very large osteogenic sarcomas, soft tissue sarcomas, melanomas, and adenocarcinomas of the alimentary tract. Malignant salivary gland tumors and prostate carcinomas respond well to neutron therapy, with high remission rates and significantly increased survival, even in locally advanced stages of the disease. Neutron beam therapy is a valuable adjunct in the management of nonresectable cancers that are resistant to conventional therapy.