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Objective: The aim of this study is to establish the methods of four facio-cervical field's conformal radiotherapy (4F-CRT) for nasopharyngeal carcinoma (NPC), and to optimize the methods for clinical practiceMaterials and Methods:40 patients with untreated NPC of T1-T4 (1997 AJCC Staging System) were rolled into this study.Conventional and four facio-cervical fields conform plans were designed for each patient using Pinnacle 8.0 three-dimension treatment planning system (3D-TPS) as follows:1Improved plan, four facio-cervical field's conform plan, anterior, posterior facio-cervical and two lateral opposing facio-cervical fields; 2Conventional plan, two lateral opposing facio-cervical fields delivered to the target in each plan, only with the same dose dose volume histograms (DVHs) of the targets and normal organs, brain stem, spinal cord, parotid glands, and temporal mandibular joints (TMJs) were compared and the dose distribution were evaluatedResults: 1.The dose distribution of the improved plan could meet the requirements for the target volume2There was not any significant difference in the dose of spinal cord between the two plans.The mean doses of D max for brain stem in conventional plan were much lower than those in the improved plan, though both were within safety limits3Compared with the conventional plans, the improved plan significantly decreased the hotspot areas in the target volume and had better parotid glands and temporal mandibular joints sparing effectConclusion:Compared with the conventional plan, the improved plan provides satisfactory dose coverage to the tumor volume and better sparing of the parotid gland, TMJs and other normal tissues in external beam radiotherapy of NPC.