鼻咽癌加速分割与常规分割放疗的疗效分析

Efficacy of Accelerated Fractionation Versus Conventional Fractionation for Nasopharyngeal Carcinoma

背景与目的:放射治疗是鼻咽癌重要的治疗手段,也是主要的根治方法,时间因素在放射治疗中越来越受到重视。本研究比较加速分割(每周六次)与常规分割(每周五次)放射治疗鼻咽癌的效果,以期在不增加并发症的情况下提高疗效。方法:回顾性分析339例首程放疗鼻咽癌患者,每周六次组181例,每周五次组158例,采用6MVX直线加速器外照射,每次2.0Gy,每天一次,鼻咽部总剂量64～72Gy,共32～36次;颈部治疗总剂量62～68Gy,共31～34次,预防总剂量50～52Gy,共25～26次。N3期患者均配合化疗。结果:每周六次组早期反应(皮肤、粘膜的Ⅲ级反应出现率分别为5.2%和14.8%,Ⅳ级反应5例)较每周五次组(3.3%和9.2%,Ⅳ级反应1例)为重,但均可耐受,晚期损伤(放射性脑病、脊髓炎、张口困难、口干、听力下降、颈部组织纤维化)无明显加重(P为0.519～0.814)。每周六次组1、3、5年局控率和5年生存率分别为98.9%、95.3%、88.4%和69.6%,每周五次组分别为98.1%、88.6%、79.7%和51.3%,3、5年局控率和生存率比较差异有统计学意义(P<0.05),1年局控率和生存率比较差异无统计学意义(P>0.05)。每周六次组无癌生存率(68.0%)亦较每周五次组(48.1%)高且有统计学意义(P<0.05)。结论:每周六次加速分割放疗方法患者能耐受,晚期损伤无明显加重,3、5年局控率和生存率均比每周五次组有所提高,且无癌生存率亦有改善。

BACKGROUND ＆ OBJECTIVE Radiotherapy is an important treatment for nasopharyngeal carcinoma （NPC）. Timing of radiotherapy has attracted more attention nowadays. This study was to assess the efficacy of accelerated fractionation （six fractions per week） versus conventional fractionation （five fractions per week） for NPC, thus to improve treatment efficacy without increasing complications. METHODS： Three hundred and thirty-nine NPC patients treated with radiotherapy were retrospectively analyzed, including 181 patients in the accelerated fractionation group and 158 patients in the conventional fraction group. All patients were radiated using a 6MV X-ray beam, 2 Gy per fraction, once a day. A total dose （TD） of 64- 72 Gy, divided into 32-36 fractions, were irradiated to the nasopharyngeal region; a TD of 62-68 Gy, divided into 31-34 fractions, were irradiated to the cervical region. The TD of prophylaxsis was 50-52 Gy, divided into 25- 26 fractions. All N3 patients received adjunct chemotherapy. RESULTS, The 1-, 3- and 5-year local control and survival rates of the accelerated fractionation group and the conventional fractionation group were （98.9% and 98.3%） vs. （98.1% and 96.8%）, （95.5% and 91.2%） vs. （88.2% and 80.4%）, （87.3% and 69.6%） vs. （76.6% and 51.3%）, respectively. The 3- and 5-year local control and overall survival rates between the two groups were significantly different （P=0.079 and P=0.0011 vs. P=0.09 and P=0.0001 ）. The incidence of acute reactions was higher in the accelerated fractionation group than in the conventional fractionation group; but the incidence of delayed reactions between the two groups was not significantly different. The diseasefree survival was significantly longer in the accelerated fractionation group than in the conventional fractionation group （P=0.002）. CONCLUSION Compared with conventional fractionation, accelerated fractionation significantly improves the 3- and 5-year local control and overall survival rates, as well as the disease-free rate for NPC patients without increasing delayed toxicity.