中文摘要：

目的：探讨鼻咽癌适形调强放疗（intensity modulate radiation therapy，IMRT）患者各涎腺功能的保护方法。方法：选取2010年3月至2012年11月101例连续于中山大学肿瘤医院接受IMRT鼻咽癌患者，勾画危及器官，包括腮腺、颌下腺、口腔，于3、6、12、18、24个月复查时采用面对面访谈式问卷调查评分口干程度情况，并结合剂量体积直方图（dose-volume histograms，DVH）进行分析。结果：腮腺平均剂量（MD）为37.4 Gy（患侧），33.8 Gy（健侧）；颌下腺MD为51.6 Gy（患侧），45.7 Gy（健侧）；口腔MD为38.2 Gy。77.2%（78/101）患者放疗结束后6个月口干症状明显改善，1年后中度（G3）以上口干患者〈5.0%（5/101）。结论：随着时间的推移，放疗后口干燥症明显改善；限定至少一侧腮腺V30～35≤50.0%，至少一侧颌下腺V40～45≤66.7%～50.0%，口腔MD〈40 Gy可有效保护唾液腺功能。

英文摘要：

Objective：To investigate the protective effect of intensity-modulated radiotherapy （IMRT） on salivary gland function in nasopharyngeal carcinoma （NPC） patients. Methods：In total, 101 NPC patients who were admitted from March 2010 to November 2012 were enrolled in this study. The parotid gland, the submandibular gland, and the oral cavity were sketched as the organs at risk （OARs）. The patients were treated with IMRT and were evaluated through a face-to-face interview using a dry mouth assessment ques-tionnaire during the follow-up visits at 3, 6, 12, 18, and 24 months. The dose volume histogram of the salivary gland of the patients was also considered. Results：The mean doses （MDs） in the parotid gland were 37.4 and 33.8 Gy in the affected and uninjured sides, respec-tively. Meanwhile, the MDs in the submandibular glands were 51.6 and 45.7 Gy in the affected and uninjured sides, respectively. The MD of the oral cavity was 38.2 Gy. At 6 months after the treatment, the symptom of xerostomia was significantly improved in 77.2%of the patients （78/101）. One year later, only less than 5%of the patients complained of having G3 or higher-grade xerostomia. Conclu-sion：With time, xerostomia significantly improved after the radiotherapy. At least one of the V30 to V35 of the parotid gland was≤50.0%, whereas at least one of the V40 to V45 of the submandibular glands was≤66.7%-50.0%. The MD for the oral cavity should be〈40 Gy to effectively protect salivary gland function.