Elective neck irradiation for squamous cell carcinoma of the head and neck: analysis of time-dose factors and causes of failure.

This is an analysis of 190 patients who were treated with radiation therapy alone at the University of Florida, between October 1964 and December 1982, for T1-4 N0 squamous cell carcinoma of the head and neck; in all patients, the primary lesion was permanently controlled and the neck was evaluable for at least 2 years following radiation therapy. The control of neck node disease is analyzed as a function of elective neck irradiation, the dose of radiation delivered to the first-echelon lymph nodes, and the likelihood that occult disease was present in the neck prior to treatment.