...Cmax of Erlotinib and Its Metabolite OSI-420`Erlotinib Tmax`AUC Time 0-infinite (AUCinf) of Erlotinib and Its Metabolite OSI-420`Number of Positive Mutations of EGFR and Downstream Pathways`Ability of Erlotinib to Inhibit EGFR Signaling`Correlation Between Standard Magnetic Resonance Imaging and Investigational Radiologic Techniques in Assessing Tumor Response to This Treatment`To Prospectively Investigate the Technical Factors Involved in Planning and Administering Conformal Fractionated RT as Outlined in This Study, and to Correlate RT Dosimetry With Patterns of Failure, Standard and Investigational Imaging and Toxicity`Plasma and CSF Levels of VEGF, bFGF, and SDF1`Number of Participants Experiencing Grade 3 or 4 Toxicity Events...