Background and purpose: To evaluate the therapeutic benefits by adding chemotherapy (+C) and/or accelerated-fractionation (AF) for patients with T3-4N0-1M0 nasopharyngeal carcinoma. Materials and methods: From 1999 to 2004, 189 eligible patients were randomized to one of four treatment groups (CF/CF + C/AF/AF + C). The number of fractions/week was 5 for the CF groups and 6 for the AF groups. Patients in the +C groups were given concurrent cisplatin plus adjuvant cisplatin and fluorouracil. Results: The AF + C group achieved significantly higher failure-free rate (88% at 5-year) than the CF group (63%; p = 0.013), the AF group (56%; p = 0.001) and the CF + C group (65%; p = 0.027). As compared with CF alone, the increase in late toxicity was statistically insignificant (36% vs. 20%; p = 0.25). Deaths due to cancer progression decreased (7% vs. 33%; p = 0.011) but deaths due to incidental causes increased (9% vs. 2%; p = 0.62). Improvement in overall survival reached borderline significance (85% vs. 66%; p = 0.058). Conclusions: Concurrent-adjuvant chemotherapy combined with AF significantly reduced failure and cancer-specific deaths. Although the increase in major late toxicity and incidental deaths were statistically insignificant, a subtle increase in non-cancer deaths narrowed the overall survival gain. © 2010 Elsevier Ireland Ltd. All rights reserved. ; Link_to_subscribed_fulltext