Between July 1977 and March 1988, 31 patients with an adenoidcystic carcinoma were treated with fast neutrons of a 14 MeV-DT-generator at our department. Primary locations were: parotid gland eight cases, paranasal sinus five cases, submandibular gland five cases, trachea four cases and other locations nine cases. The median follow-up of our patients was 16 months. Most of the patients had advanced tumors. The calculated local control rate is 65% at two years.