Statistical considerations: The sample size for this trial is based on the expected local control rate of similar patients treated with standard radiotherapy. For group 1 (patients treated with definitive radiotherapy) this is difficult to predict a priori because of the expected heterogeneity of stages and primary sites of accrued patients. However, stage I-II patients treated with RT alone, and selected stage III patients treated with chemoradiotherapy have 2-year local control rates of 70-80%. For group 2 (patients treated with surgery with high-risk features necessitating post-op RT), the expected local control rate is also approximately 70%. Assuming a power of 70%, significance of 5%, and a historical rate of local control of 75% (combined), the required number of patients to detect a 10% change in local control is 120.7. We will therefore accrue 120 patients, at an anticipated rate of 2-3 patients per month for 2-4 years.