后程三维适形放射治疗鼻咽癌的近期疗效观察

Observation of Short-Term Result of Late-Course Three Dimensional Conformal Radiation Therapy for Nasopharyngeal Carcinoma

目的 分析鼻咽癌后程三维适形放射治疗（3DCRT）近期疗效。方法 32例初治无远处转移的鼻咽癌患者，采用分三阶段对原发灶放射治疗。第一段用面颈联合野常规放疗DT 36Gy，第二段用耳前野放疗DT 14Gy，第三段用3DCRT DT 20～25Gy。总照射剂量DT 70～75Gy。颈部用切线野或者加电子线野作常规分割照射，设野上界保持与主野下界衔接，对颈淋巴结阴性照射DT 50Gy，淋巴结阳性照射DT 66～70Gy。结果 局部肿瘤消退率（有效率）100％，完全缓解率93、75％，1年生存率100％。无严重并发症。结论 鼻咽癌后程三维适形放射治疗可以获得比较理想的剂量分布，近期疗效满意。

Objective To evaluate the short-term efficacy of late-course 3-dimensional conformal radiation therapy （3DCRT） for nasopharyngeal carcinoma （NPC） . Methods From 32 NPC patients with untreated but distant metastasis. The radiation schedule was divided into three phases. The first was to all were treated by conventional radiotherapy with 36 Gy on the facio-neck field, then followed received 14 Gy on the preauricular field and 20-25Gy with 3DCRT.The whole dose was 70- 75 Gy. Routine fraetionated irradiation was made on neck with tangential field or both tangential field and negatron field. The upperbound of designed therapeutic field was set to connect with the lowerbound of main therapeutic field. Patients without lymph node metastasis were given 50 Gy to the neck, while 66 - 70 Gy was delivered to node positive groups. Results Local completion was observed in 100 % , the eomplete response was 93.75 % , giving a 1-year survival rate of 100%, without serious consequence. Conclusions Late-course 3-dimensional conformal radiation therapy yields better dose distribution in nasopharyngeal carcinoma. The preliminary clinical result is encouraging.