鼻咽癌局部复发适形放疗近期疗效分析

目的：采用适形放疗提高鼻咽癌局部复发的治疗效果，探讨最佳剂量分割方法。方法：1997年9月至2000年2月对41例鼻咽癌局部复发病人行适形放疗。27例常规外照射39Gy，在3周内分30次完成后进行低分割适形放疗，80％等剂量线4～7Gy/次，总量20～24Gy，分4次在2周内完成；14例全程超分割适形放疗，90％等剂量线59.8Gy,4.6周内分46次完成。结果：适形放疗的等剂量线分布在三维方向上与靶区适形。急性放射性粘膜炎、后组颅神经损伤、张口困难两组相似，低分割组22％鼻咽粘膜坏死，3.7％视神经损伤。超分割组无鼻咽粘膜坏死、视神经损伤。两组治疗有效率均达93％。结论：鼻咽癌局部复发病人采用超分割适形放疗取得满意的近期效果，低分割适形放疗不宜采用。

Short-Term Effect of Conformal Radiotherapy for Recurrent Nasopharyngeal Carcinoma

Objective： The current study was designed to evaluate the treatment results of nasopharyngeal carcinoma by conformal radiotherapy. Methods： From September 1997 to February 2000, a total of 41 cases of recurrent nasopharyngeal carcinoma were treated by conformal radiotherapy. Among them, 27 cases were treated by late-course hypofraction conformal radiotherapy with the dose of 20- 24 Gy at 80％ isodose, 4- 7 Gy per time, following routine radiotherapy of 39 Gy/30f/3weeks. Fourteen cases received total-course conformal radiotherapy with the dose of 59.8 Gy/46f/4.6weeks at 90％ isodose. Results： The reference isodose curves conform to the target in three dimensions in conformal radiotherapy. The acute radiation mucositis, cranial nerve paralysis and trismus incidence were similar in two groups, however, in the hypofractionation group 22％ developed necrosis of nasopharyngeal mucosa, 3.7％ developed reduced optic nerve lesion, whereas none of the hyperfractionation group had these complications. The tumor response rate were both 93％ for two groups. Conclusion： Hyperfraction conformal radiotherapy is effective in the treatment of recurrent nasopharyngeal carcinoma and has relatively lower incidence of radiation complication.