Patients presented with non-keratinizing NPC and stage T3-4N1M0/TxN2-3M0 are randomly assigned to receive concurrent chemoradiotherapy plus adjuvant chemotherapy (investigational arm)or concurrent chemoradiotherapy (control arm). Patients in both arms receive radical radiotherapy and cisplatin (40mg/m2 on day 1) weekly during radiotherapy. Patients in the investigational arm receive cisplatin (80mg/m2 on day 1) and fluorouracil (800mg/m2 on Day 1 to 5) every four weeks for three cycles after completion of radiotherapy. Patients are stratified according to the treatment centers. The primary end point was failure-free survival (FFS). Secondary end points included overall survival (OS), distant failure-free survival (D-FFS), locoregional failure-free survival (LR-FFS), the initial response rates after treatments, toxic effects and treatment compliance. All efficacy analyses were conducted in the intention-to-treat population; the safety population included only patients who received their randomly assigned treatment.