常规放疗加后程三维适形放射治疗鼻咽癌的近期疗效观察

[目的]探讨鼻咽癌常规分次外照射加后程三维适形放射治疗（3D-CRT）的近期疗效。[方法]对30例初治无远处转移的鼻咽癌患者，采用分三阶段对原发灶进行治疗，第一阶段用面颈联合野常规放疗DT36Gy，第二阶段改耳前野或鼻前野放疗DT 14Gy，第三阶段用3D-CRT DT20～25Gy，总照射剂量70～75Gy。颈部用切线野或者加电子线野作常规分割照射，改野上界保持与面颈联合野下界衔接，对颈淋巴结阴性照射DT 50 Gy，颈淋巴结阳性照射DT 70 Gy。同期配对法选择30例常规放疗患者作为常规组，比较两组的近期疗效和急性放射反应。[结果]适形组完全缓解率达100％，常规组82％，无严重并发症发生。两组3年生存率相比较差异无统计学意义（P〉0．05）。[结论]鼻咽癌常规放疗加后程三维适形放射治疗鼻咽癌，患者耐量性良好，近期疗效较常规放射治疗理想。

Observation on Shod-Term Effect of Late-Course Three-Dimensionai Conformal Radiation Therapy for Nasopharyngeal Carcinoma

[Objective] To explore the short-term efficacy of late-course 3-dimensional conformal radiation therapy （3DCRT） for nasopharyngeal carcinoma（NPC）. [Methods]Thirty NPC patients without distant me- tastasis between January 2003 and April 2005（CRT group） received three phases of radiation therapy. At the first phase, patients were treated by conventional radiotherapy with 36 Gy on the face-neck field. At the sec- ond phase, patients were treated by radiotherapy with 14Gy on the preauricular field. At the third phase, patients were treated by 3D-CRT with 20-25 Gy,and the whole dose was 70-75 Gy. Routine fractionated irradiation was made on neck with tangential field or both tangential field and negation field. The upper-bound of designed therapeutic field was set to connect with the lower-bound of main therapeutic field. Patients without lymph node metastasis were given 50Gy to the neck, and 70Gy was delivered to node positive groups. This group was matched with 30 NPC patients who were treated with conventional method alone （Routine group）. The treatment result and acute toxicity between the two groups were compared. [Results] The complete re- sponse（CR） rate of primary tumor was achieved 100% in CRT group and 82% in routine group, and no severe complications were found. There was no difference in the overall survival between the two groups （ P 〉0.05）. [Conclusion] The patients have good tolerance and short-term response with late-course three-dimensional conformal radiotherapy after external irradiation for nasopharyngeal carcinoma.