Reduced-dose radiotherapy for Epstein-Barr virus DNA selected staged III nasopharyngeal carcinoma: A single-arm, phase 2 trial

•A total of 216 patients with low-risk stage III NPC were enroled in this study.•One hundred and sixteen patients had CR/PR and undetectable EBV DNA after IC.•Sixty Gy RT is non-inferior to the 70 Gy RT in low-risk stage III NPC.•No grade 3+ long-term adverse event was found in 60 Gy cohort.•The 2-year PFS rate of the whole cohort was 90.7%.