Background: The purpose of this study was to analyze factors influencing outcome in patients who received postoperative irradiation for advanced squamous cell carcinoma of the oral cavity.
Methods: Between October 1964 and November 2000, 226 patients with 230 previously untreated primary invasive squamous cell carcinomas of the oral cavity were treated postoperatively with continuous-course external beam irradiation. All patients had a minimum follow-up of 2 years (analysis, November 2002). No patient was lost to follow-up.
Results: The 5-year actuarial rates of locoregional control by pathologic American Joint Committee on Cancer stage were: stage I, 100%; stage II, 84%; stage III, 78%; and stage IV, 66%. Recurrence of cancer above the clavicles developed in 55 patients (24%). In multivariate analysis of locoregional control, positive margins, vascular invasion, perineural invasion, extracapsular extension, and T classification remained significant.
Conclusions: This article provides additional data defining relatively favorable and unfavorable groups of patients in the postoperative setting. Dose recommendations are re-examined and selectively increased for high-risk patients.