Selection for Radiation Alone vs. Chemoradiotherapy For CR/PR patients with CR at primary site following induction chemotherapy, locoregional therapy will be risk-adjusted according to baseline tumor stage/characteristics. Local therapy will be 1) radiotherapy as a single modality for Tx (T1-2), T0-1 or exophytic T2, N0-2a disease, or will be 2) concomitant chemoradiotherapy for Tx (T3), endophytic T2, T3, N2b-c disease. Patients with PR at primary site will receive concurrent chemotherapy and reduced dose radiation.