Javadi Saba, Eckstein Jacob, Ulizio Vincent, Palm Russell, Reddy Krishna, Pearson David
Department of Radiation Oncology, University of Toledo, 1325 Conference Drive, Toledo, OH 43614, USA.
Department of Radiation Oncology, University of Toledo, 1325 Conference Drive, Toledo, OH 43614, USA.
Med Dosim. 2019;44(4):365-369. doi: 10.1016/j.meddos.2019.01.007. Epub 2019 Mar 7.
The goal of this retrospective study was to determine the benefit in using abdominal compression to reduce tumor motion for patients treated with lung stereotactic body radiotherapy. Forty-four lung lesions (n = 44) from 37 patients (N = 37) treated at the University of Toledo's Dana Cancer Center were assessed by determining the overall tumor displacement along with possible surrogates such as change in tidal volume and diaphragm displacement, with and without abdominal compression. Measurements of lung capacity were acquired from the 4DCT at maximum and minimum respiration in order to determine the tidal volume, with and without abdominal compression. Tumor centroid and diaphragm apex motion was then assessed in 3 dimensions from phase 0 to phase 50. This was measured in centimeters using the ruler method on MIM software, both with and without the compression belt. Change in overall tumor movement was 0.61 cm ± 0.09 cm with compression, and 0.60 cm ± 0.09 cm without the compression belt. Delta tumor motion was reduced in 5 cases, increased (made worse) in 6 cases, and did not clinically impact the remaining 33 cases. Average tidal volume with abdominal compression was 379.7 mL or 12.0% ± 0.724% of total lung volume while average tidal volume without abdominal compression was 337.7 mL or 10.5% ± 0.649% of total lung volume. Change in diaphragm position throughout the breathing cycle was 1.21 cm ± 0.10 cm with compression, and 1.28 ± 0.13 cm without the compression belt. These findings indicate that abdominal compression may not be an effective method in the reduction of respiratory motion, and can even negatively impact tumor motion by increasing its displacement. Compression decreased tumor motion in 5 out of the 44 cases studied. The 5 cases that benefitted tended to be lesions close to the diaphragm but these 5 corresponded to less than half of the inferior lesions, suggesting that even inferior lung lesions may not be prime candidates for abdominal compression.
这项回顾性研究的目的是确定在接受肺部立体定向体部放射治疗的患者中，使用腹部压迫来减少肿瘤运动的益处。对托莱多大学达纳癌症中心治疗的37例患者（N = 37）的44个肺部病变（n = 44）进行了评估，通过确定有无腹部压迫时肿瘤的整体位移以及诸如潮气量变化和膈肌位移等可能的替代指标。在有和没有腹部压迫的情况下，从4DCT获取最大和最小呼吸时的肺容量测量值，以确定潮气量。然后从第0相到第50相在三个维度上评估肿瘤质心和膈肌顶点运动。使用MIM软件上的标尺法以厘米为单位进行测量，有和没有压迫带时均进行测量。有压迫时肿瘤整体运动变化为0.61 cm±0.09 cm，没有压迫带时为0.60 cm±0.09 cm。5例肿瘤运动差值减小，6例增大（变差），其余33例在临床上未受影响。有腹部压迫时的平均潮气量为379.7 mL，占肺总量的12.0%±0.724%，而没有腹部压迫时的平均潮气量为337.7 mL，占肺总量的10.5%±0.649%。有压迫时整个呼吸周期中膈肌位置的变化为1.21 cm±0.10 cm，没有压迫带时为1.28±0.13 cm。这些发现表明，腹部压迫可能不是减少呼吸运动的有效方法，甚至可能通过增加肿瘤位移对肿瘤运动产生负面影响。在所研究的44例病例中，压迫使5例肿瘤运动减小。受益的5例往往是靠近膈肌的病变，但这5例占下叶病变的不到一半，这表明即使是下叶肺部病变也可能不是腹部压迫的主要候选对象。
