鼻咽癌不同放疗技术的剂量学对比

目的比较不同放疗技术对鼻咽癌肿瘤靶区及各危及器官的剂量学影响。方法选择鼻咽癌患者8例,应用治疗计划系统对每个病例分别模拟常规分割二维放疗（CRT）、后程三维适形放疗（3DCRT）和全程调强适形放疗（IMRT）,比较各靶区和危及器官的受照剂量及相关受照剂量体积。结果在临床靶区1（CTV1）、临床靶区2（CTV2）调强组的靶区覆盖优于另两组（P〈0.05）。调强组脑干和脊髓的最高受量分别为57.25 Gy和42.52 Gy,腮腺、颞叶、颞颌关节和下颌骨的平均受量分别为38.66、19.84、44.53、43.5 Gy,且各危及器官超过最小耐受剂量（TD5/5）的体积均明显低于另两组（P〈0.05）。结论调强技术能够减少大多数危及器官的受照剂量。

Dosimetric comparison among different treatment planning for the patients with nasopharyngeal carcinoma

Objective To investigate the dosimetric effect on target volumes and the organs at risk （OARs） with conventional radiotherapy （CRT）,late-course three dimensional conformal radiotherapy （late-course 3DCRT） and intensity-modulated radiotherapy （IMRT） in the treatment of nasopharyngeal carcinoma （NPC）. Methods Eight cases with NPC were selected. Three plans were designed for every ease to compare the dose of target volumes or OARs and the related volume among the plans and carried out by the treatment planning system （TPS）. Results To the clinical target volume 1 （CTV1） and the clinical target volume 2 （CTV2）, the prescribed dose coverage with IMRT were all superior to other two groups （P 〈 0.05 ）. At the IMRT group, the average maximum dose of brain stem and spinal cord were 57.25 and 42.52, respectively, the average mean dose of parotid, temporal, temporomandibular joint （TMJ） and mandible were 38.66,19.84,44.53,43.5 Gy, respectively, and the volume covered by more than minimum tolerance dose （TDS/5） at the OARs mentioned above were less than the other two groups （ P 〈 0.05 ）. Conclusion IMRT may reduce the exposure doses of most OARs.