摘要
目的基于4DCT扫描探讨胸段食管癌原发肿瘤靶区（GTV）三维方向位移及其影响因素。方法65例胸段食管癌患者在自由呼吸状态下完成4DCT、3DCT模拟定位，获取呼吸周期中GTV左右（LR）、前后（AP）和上下（sI）方向位移，记录GTV上下缘与主动脉弓及隆突下缘、双侧膈顶距离。依据年龄、性别、肿瘤部位、病理类型、体积和长度分组，分析上述因素对GTV位移的影响及肿瘤上下缘位置差异与位移相关性。结果GTV在LR、AP、SI方向位移分别为0．15、0．12、0．34cm，胸下段GTV在LR及AP方向位移明显大于上、中段（P=0．036、0．014），SI方向相似（P=0．123）。性别、年龄及体重指数差异对GTV位移无影响（PLR=0．46、0．96、0．73，PAP，=0．924、0．594、0．865，Psl=0．955、0．264、0．139），肿瘤长度差异仅对LR方向位移有影响（P=0．014）；GTV位移与淋巴结存在与否无相关性（P=0．502、0．665、0．815），但与其上下缘距离气管隆突距离呈负相关（P=0．000—0．014）。结论平静呼吸状态下胸段食管癌GTV的sI方向位移最大，而年龄、性别、体重等及纵隔转移淋巴结存在与否并不影响靶区外扩范围，靶区分次内外扩范围应参照肿瘤分段及食管癌与气管隆突的毗邻关系。
Objective To investigate the three-dimensional （3D） motion of gross tumor volume （GTV） and its influential factors in patients with primary thoracic esophageal cancer based on four- dimensional CT （4DCT）. Methods Sixty-five patients with thoracic esophageal cancer underwent 3DCT and 4DCT simulation scans during normal breathing to measure the centroid motions of GTV in the left-right （LR）, anterior-posterior （AP）, and superior-inferior （SI） directions. The distances from the upper and lower edges of GTV to the lower edges of the aortic arch and tracheal carina and the diaphragmatic dome at both sides were measured. The patients were grouped based on age, sex, and the location, pathological type, volume, and length of tumor. The impacts of the above factors on GTV motion and the correlation between the positions of tumor upper/lower edges and GTV motion were analyzed. Results The centroid motions of GTV in the LR, AP, and SI directions were 0. 15 cm, 0. 12 cm, and 0. 34 cm, respectively. The patients with lower thoracic esophageal cancer had lager centroid motions of GTV in the LR and AP directions than those with upper and middle thoracic esophageal cancer （P = 0. 036 and 0. 014）, but there was no significant difference in the centroid motion of GTV in the SI direction （P = 0. 123 ）. There were no relationships between GTV motion and the sex, age, and body mass index （BMI） of patients （ PLR = 0. 464, 0. 962, and 0. 727, PAt, = 0. 924, 0. 594, and 0. 865, Psx = 0. 955, 0. 264, and 0. 139）. A significant difference was found between patients with different tumor lengths in terms of the GTV motion in the LR direction （P = 0. 014）. GTV motions were not correlated with whether lymph node metastasis occurred （P = 0. 502, 0. 665, and 0. 815 ）, but they were negatively correlated with the distances between the upper and lower edges of GTV and the tracheal carina （P = 0. 000-0. 014 ）. Conclusions The maximum GTV motion is seen in the SI direction among patients with thoracic esophageal cancer during normal breathing. Age, sex, BMI, and mediastinal lymph node metastasis have no impacts on target volume expansion, and appropriate site-specific internal target volume expansion should be determined in consideration of the tumor location and the distances between the upper and lower edges of GTV and the tracheal carina.
出处
《中华放射肿瘤学杂志》
CSCD
北大核心
2013年第4期282-285,共4页
Chinese Journal of Radiation Oncology
基金
山东省科技发展计划项目（2011YD18039）
山东省科技发展计划项目（2011YD18082）
关键词
食管肿瘤
放射疗法
体层摄影术
x线计算机
四维
靶区位移
影响因素
Esophageal neoplasms/radiotherapy
Tomography, X-ray computed, four- dimensional
Target displacement
Influencing factors
