Abstract:At present, intensity modulated radiation therapy has been the main treatment of nasopharyngeal carcinoma. In the course of 6~7 weeks, most physicians use the initial formulation of the radiotherapy plan. Studies have indicated that the reduction of primary tumor and lymph nodes, as well as the reduction of normal tissue and body surface profile due to the weight loss, will affect the dose distribution of the target and the organs at risk, so as to influence the therapeutic effect of some patients. Therefore, it is necessary to reset and modify the target volumes during the radiotherapy for nasopharyngeal carcinoma.

Key words:Nasopharyngeal neoplasms,Radiotherapy, intensity-modulated,Target volumes,Organs at risk