Evaluation of a neutron boost in head and neck cancer. Results of the randomized RTOG trial 78-08

Abstract

Patients with untreated squamous cell cancer of the head and neck region were randomized to receive either a boost of 25-30 Gy using photon-beam irradiation (photons) or an equivalent boost using neutron-beam irradiation (neutrons). All patients received an initial 45-50 Gy of wide-field photon irradiation. A total of 57 patients was evaluable on the neutron arm and 58 were evaluable on the photon arm. The proportion of patients with complete responses was 60 and 64% on the neutron and photon arms, respectively. The locally disease-free proportion at 2 years was estimated to be 20 and 31%, and the 2-year survival was estimated to be 32 and 41%, respectively. These differences are not statistically significant. There was a higher rate of severe complications on the neutron arm, 16 versus 7%. Thus, there was no evidence that a neutron boost produces better initial tumor clearance, local tumor control, or survival than a photon boost, and it may produce more complications.