Figure 1. Kaplan–Meier PFS (A), LRFS (B), OS (C) and DMFS (D) curves for 549 patients with NPC with undetectable/detectable EBV DNA level after induction chemotherapy. Abbreviations: PFS = progression-free survival; OS = overall survival; LRFS = local-regional relapse-free survival; DMFS = distant metastasis-free survival; NPC, nasopharyngeal carcinoma; and EBV= Epstein–Barr virus.