应用CBCT动态观察鼻咽癌调强放疗中肿瘤、唾液腺位置变化

Position Changes of Tumor、Salivary Gland During IMRT for Patients with NPC Using CBCT

目的通过CBCT动态观察鼻咽癌患者调强放疗中肿瘤、唾液腺位置变化。方法利用直线加速器CBCT,每周采集鼻咽癌患者调强放疗中的CBCT影像,观察患者GTVnx、GTVnd、腮腺、颌下腺的位置变化。结果肿瘤及唾液腺位置逐步发生移动,在第21次放疗前后时变化较显著。除GTVnx变化与初始体积无关外,余均与其初始体积大小呈正相关。结论通过CBCT能动态观察鼻咽癌患者放疗中肿瘤及唾液腺位置变化。

Objective To observe the position changes of the tumor,salivary glands by Cone Beam Computer Tomography( CBCT) scan,during intensity modulated radiation therapy( IMRT) for patients with nasopharyngeal carcinoma( NPC).Methods The linear accelerator with CBCT was used to gather CBCT images weekly during IMRT for patients with NPC. The dynamic changes of position for GTVnx,GTVnd,parotid and submandibular glands were analyzed. Results The position of GTVnx,GTVnd,parotid and submandibular glands were changed significantly. The rate of changes were obvious at the 21 st time radiotherapy. All changes of volume were positively related to its initial size besides GTVnx. Conclusion The changes of tumor and salivary glands can be dynamically observed by CBCT scanning during radiotherapy for patients with NPC.