初治鼻咽癌调强放疗的前瞻性多中心临床研究

A prospective, multicentric clinical study of intensity modulated radiotherapy in the treatment ofnasopharyngeal carcinoma

目的观察调强放疗（IMRT）初治鼻咽癌的临床疗效及不良反应，并分析影响预后的因素。方法2006-2008年，6个治疗中心共300例经病理活检确诊为鼻咽癌的初治患者接受全程IMRT。UICC／AJCC 2002分期Ⅰ、Ⅱ、Ⅲ、Ⅳa＋b期分别为6、45、141、108例。放疗处方剂量鼻咽原发灶计划把体积为70～74Gy，颈部转移淋巴结计划把体积为68-70 Gy，计划靶体积-1为60～64Gy，计划靶体积-2为50～54 Gy，均分30次6周完成。Ⅲ～Ⅳ。期患者接受了以铂类为基础化疗。Cox法多因素预后分析。结果随访率为99．7％。4年局部控制率、区域控制率、无远处转移率、无瘤生存率及总生存率分别为94．O％、95．5％、87．4％、80．8％及86．1％。急性1、2、3级放射性黏膜炎分别占18．0％、48．7％、33．3％，晚期0、1、2级口干分别占12．0％、75．7％、12．3％。18、15、42例出现局部、颈部淋巴结复发、远处转移。多因素分析显示N分期影响总生存率（x^2=5．17，P=0．023）、无远处转移率（x^2=6．91，P=0．009）、无瘤生存率（X^2=8．15，P=0．004）。结论IMRT可提高初治鼻咽癌患者临床疗效，不良反应可耐受，治疗失败最主要原因为远处转移，N分期是影响预后的主要因素。

Objective To evaluate the treatment efficacy, toxicities and prognostic factors of nasopharyngeal carcinoma （ NPC ） treated with intensity modulated radiation oncology （ IMRT ） . Methods Between January 2006 and August 2008, 300 patients with pathologically diagnosed NPC from 6 center received IMRT. The number of patients with stage I , ]1 , m and IVa＋b disease （UICC/AJCC 2002 staging system） were 6, 45,141 and 108, respectively. The prescription doses were as follows ：70 - 74 Gy/30f to planning target volume of primary nasopharynx tumor （ PTVnx ）, 68 - 70 Gy/30f to planning target volume of positive lymphnode （ ptvnd ）, 60 - 64 Gy/30f to higher risk region （ PTV1 ）, 50 - 54 Gy/30f to lower risk region （PTV2）. Patients with stage Ill and IVn＋b disease also received cisplatin-based chemotherapy. Cox method was used for Multivariate analysis. Results The follow-up rate was 99. 7%. The 4-year rate of local control, regional control, metastasis-free survival （DMFS） , disease-free survival （DFS） and overall survival （OS） was 94. 0%, 95.5%, 87. 4% , 80. 8% , 86. 1% , respectively. Mucositis was the most severe acute toxicity, with 18.0% grade 1, 48. 7% grade 2, 33.3% grade 3. No patient suffered from grade 4 mucositis. Xerostomia was the most common late toxicity, with 12. 0% grade 0, 75. 7% grade 1, 12. 3% grade 2. No grade 3 -4 xerostomia was observed. There were 18,15 and 42 patients failed in local, regional and distant metastasis, respectively. Multivariate analysis showed that N stage was the only prognostic factor for OS （X^2 =5.17,P=0.023）,DMFS （X^2 =6.91,P=0. 009） and DFS （X^2 .=8. 15,P=0.004） in these patients. Conclusions IMRT can improve the treatment efficacy of NPC. The acute and late toxicities were tolerated. Distant metastasis becomes the main treatment failure. N stage is a significant prognostic factors.