Fast neutron radiotherapy for locally advanced XXXX : results of an RTOG randomized study.

@entity1 @entity263 @entity5
Between June 1977 and April 1983, the Radiation Therapy Oncology Group (RTOG) sponsored a Phase III randomized study investigating fast neutron radiation therapy in the treatment of @entity1 with locally advanced (Stage C and D1) @entity263 . @entity1 were randomized to receive either conventional photon radiation therapy or fast neutron irradiation used in a mixed-beam treatment schedule (neutron/photon). A total of 91 analyzable @entity1 were entered in the study; 78 of them were treated without major protocol deviations. The two treatment groups were balanced in regard to all major prognostic variables. Actuarial curves for "overall" survival, "determinantal" survival and local/regional control are presented both for the entire group of 91 @entity1 and the 78 @entity1 treated within protocol guidelines. The overall @entity5 recurrence rate is 7% for the mixed-beam treated group of @entity1 and is 22% for the photon (X ray) treated group of @entity1 . The difference is statistically significant at the p = 0.05 level. For the entire group of 91 evaluable @entity1 , the 5-year "overall" survival rate is 62% for the mixed-beam-treated group and 35% for the photon-treated group. This difference is also statistically significant (p less than 0.05). However, this statistical significance is lost when the smaller number of @entity1 treated strictly within protocol guidelines is considered. The significance is regained (p less than 0.02) when one looks at "determinantal" survival, which uses active cancer at time of death as the failure endpoint. This study demonstrates that a regional treatment modality, in this case mixed-beam irradiation, can influence both @entity5 control and survival in @entity1 with locally-advanced @entity263 .
