鼻咽癌患者调强放射治疗后颞颌关节损伤及其影响因素

背景与目的:放射性颞颌关节损伤是鼻咽癌患者放射治疗后常见的并发症,主要表现为张口时门齿距缩小.严重的张口困难可影响进食,影响患者生活质量.本研究通过量化鼻咽癌患者调强放疗后张口困难的情况,探讨颞颌关节放射损伤的影响因素.方法:2001年2月至2003年2月,148例初治鼻咽癌患者接受调强放疗,放疗总剂量63～77 Gy,分次剂量为每次2.27～2.80 Gy,总疗程时间31～86 天.放疗前及放疗后6个月、1年、2年和3年分别用直尺测量患者门齿距.结果:全组1、2、3年累积生存率为97.26%、94.83%、92.04%.颞颌关节平均剂量17.99～51.36 Gy.Ⅰ～Ⅱ级张口困难发生率4.73%,未观察到Ⅲ级和Ⅳ级颞颌关节损伤.结论:调强放疗技术使颞颌关节受照剂量显著下降,放疗后发生严重张口困难的风险较低.

Radiation-induced temporomandibular joint damage in nasopharyngeal carcinoma patients after intensity-modulated radiotherapy

BACKGROUND & OBJECTIVE: Radiation-induced temporomandibular joint damage is a kind of common complication after radiotherapy for nasopharyngeal carcinoma (NPC) patients. Trimus is the main symptom of this damage, and severely affects the quality of life of the patients. This study was to evaluate radiation-induced temporomandibular joint damage in NPC patients treated with intensity-modulated radiotherapy (IMRT), and analyze its affecting factors. METHODS: From Feb. 2001 to Feb. 2003, 148 naive NPC patients were treated with IMRT by 2.27-2.80 Gy per fraction at a total dose of 63-77 Gy within 31-86 days. The distance between 2 dens incisivus medialis (DDIM) was measured before radiotherapy, and 6 months, 1 year, 2 years, and 3 years after radiotherapy, respectively. RESULTS: The overall 1-, 2-, and 3-year survival rates were 97.26%, 94.83%, and 92.04%. The irradiation dose to temporomandibular joint was 17.9-51.36 Gy. Seven (4.73%) patients suffered from grade I-II temporomandibular joint damage after IMRT; no patient had grade III-IV temporomandibular joint damage. CONCLUSIONS: IMRT can spare the temporomandibular joint from high dose irradiation. The risk of radiation-induced severe temporomandibular joint damage in NPC patients after IMRT is low.