Fig. 2

Kaplan–Meier survival curves of patients with N0-category NPC and ENLN in the small ENLN (<5.5 mm) and large ENLN (≥5.5 mm) groups. a Regional relapse-free survival; b disease-free survival; c overall survival; d distant metastasis-free survival. NPC nasopharyngeal carcinoma, ENLN small neck lymph node