<qa>  What is the randomized, multicenter study?OUTLINE: This is a randomized, multicenter study. Patients are stratified according to T stage T1 or T2 vs T3 or T4, N stage N0 or N1 vs N2 or N3, prior therapy complete tumor resection vs resection and radiotherapychemoradiotherapy vs radiotherapy or chemoradiotherapy alone, and prior chemotherapy yes vs no. Patients are randomized to 1 of 2 treatment arms. 