宫颈癌 IMRT 靶区及 OAR 体积与位置变化研究  

A study of changes in volume and location of target areas and organs at risk in intensity-modulated radiotherapy for cervical cancer

作　　者：陈建武[1] 刘萍[2] 陈文娟[3] 柏朋刚[3] 李江山[3] 倪晓雷[4] 陈开强[3] 李奇欣[3] 

机构地区：[1]福建医科大学附属第二医院放疗科,泉州362000 [2]福建医科大学第二临床医学院 [3]福建医科大学教学医院福建省肿瘤医院放疗科 [4]福建省龙岩市第一医院放疗科

出　　处：《中华放射肿瘤学杂志》2015年第4期395-399,共5页Chinese Journal of Radiation Oncology

基　　金：福建省卫生厅青年课题（2012-1-7）;国家临床重点专科建设项目（2012）;福建省临床重点专科肿瘤放射治疗科建设项目（2012）

摘　　要：目的：通过量化方法研究 IMRT 前与放疗中期靶区及正常组织体积与空间位置的变化。方法选取40例经过 IMRT 的宫颈癌患者。分别于放疗前及放疗剂量达27 Gy （15次）时各扫描1组 CT 图像。临床医生分别在这两组 CT 中勾画出靶区与 OAR。通过 Pinnacle 计划系统图像配准把第1次靶区与 OAR 映射至第2次 CT 图像上。分析靶区与各 OAR 体积变化，并使用体积差异法和 DICE 相似度法来评价空间位置变化情况。配对 t 检验差异。结果疗前和放疗15次的原发灶GTV、盆腔转移淋巴结 GTV 均不同（P＝0.000、0.000）。使用体积差异法评价原发灶 GTV 变化率平均为（38．64±19.50）％，范围3．16％～86.49％；盆腔转移淋巴结变化率平均为（42．49±25.68）％，范围2．79％～87.42％； OAR 中膀胱体积变化率最大，平均为（55．13±33.40）％，范围3．25％～116.01％。使用 DICE 值法评价，原发灶 GTV 平均为0．50±0.18，范围0．10～0.85；盆腔转移淋巴结 GTV 平均为0．31±0.20，范围0．00～0.71，OAR中直肠DICE参数最小，平均为0．57±0.14，范围0．18～0.76。结论 IMRT 宫颈癌患者疗前和疗中靶区及正常组织体积与空间位置发生明显变化，应及时修改放疗计划确保靶区足够剂量，同时避免 OAR 超过剂量限值是非常有必要的。Objective To investigate the changes in volume and spatial location of target areas and normal tissues before and during intensity.modulated radiotherapy （IMRT） for cervical cancer by quantitative means. Methods Forty patients with cervical cancer who were treated with IMRT were enrolled as subjects. Computed tomography （ CT） was performed before IMRT and during IMRT when a dose of 27 Gy （ 15 fractions） was reached. Clinicians delineated the target areas and organs at risk in the two groups of CT images. The target areas and organs at risk in one group of images were mapped to the other group of CT image by image registration using the Pinnacle treatment planning system. Volume changes in target areas and organs at risk were analyzed, and changes in the spatial location were evaluated by volume difference method and Dice similarity method. Comparison was made by paired t.test. Results There were significant differences in gross target volumes of primary tumor lesions （ GTV.T） and pelvic metastatic lymph nodes （GTV.N） before and during IMRT （ P= 0. 000; P= 0. 000）. According to the evaluation by volume difference method, the average rate of change in GTV.T was （38.64±19. 50）% with a range between 3. 16%and 86. 49%, while the average rate of change in GTV.N was （42.49± 25. 68）% with a range between 2. 79% and 87. 42%. In the organs at risk, the bladder had the maximum rate of volume change, the average of which was （55.13±33. 40）% with a range between 3. 25% and 116. 01%. According to the evaluation by Dice similarity method, the average Dice similarity coefficient for GTV.T was 0.50± 0. 18 with a range between 0. 10 and 0. 85, while the average Dice similarity coefficient for GTV.N was 0.31±0. 20 with a range between 0. 00 and 0. 71. The rectum had the minimum Dice coefficient in the organs at risk, the average of which was 0.57± 0. 14 with a range between 0. 18 and 0. 76 . Conclusions For patients with cervical cancer to receive IMRT, since there are substantial changes i

关 键 词：宫颈肿瘤/ 调强放射疗法 DICE 参数 体积变化率 

分 类 号：R737.33[医药卫生—肿瘤]