A re-evaluation of split-course technique for squamous cell carcinoma of the head and neck

Therapeutic results of split-course vs. continuous-course external beam irradiation were analyzed retrospectively in 468 consecutive patients with squamous cell carcinoma of the oral cavity, oropharynx, nasopharynx, hypopharynx, and supraglottic larynx who were treated with curative intent at the University of Florida between September 1964 and August 1976. 214 patients received split-course treatment and 254 were treated by the continuous-course method. Except for the planned 14–16 day interruption after 2820–3000 rad in the split-course group, the techniques and total doses of irradiation did not differ. Local control was poorer for all T-stages in patients who were treated by the split-course technique. Control of neck disease by irradiation alone was also poorer among split-course irradiation patients. For each stage of disease, patients who received continuous-course irradiation had approximately 10% higher 5-year survival rates than patients who were treated by the split-course technique. The rate of development of late radiation complications was similar for the 2 treatment techniques. Routine use of the split-course technique has been discontinued since the dose required to compensate for the rest interval is unknown.