主动呼吸控制方法在非小细胞肺癌精确放疗中的应用

目的:评价主动呼吸控制方法( activebreathing control, ABC)在非小细胞肺癌(non smallcell lung cancer, NSCLC)精确放疗中的应用及其在减小放射性肺和脊髓损伤方面的作用。方法:对10例周围型NSCLC患者在适形放疗定位时分别在自由呼吸(free breathing, FB)状态下常规轴位扫描及ABC时螺旋CT快速扫描采集图象,将两套图象传输至计划系统,分别制定适形放疗计划,计算和比较2个计划的大体靶区(gross tumor volume, GTV)、临床靶区(clinical target volume, CTV)、计划靶区(planning target volume,PTV)、双肺V20、平均受量(Dmean)和脊髓最大受量。结果:ABC计划的GTV、CTV、PTV、V20、Dmean和脊髓最大受量比FB计划均要小,差异有统计学意义,P< 0. 01, (P 值分别为0 .000、0 .000、0. 000、0. 000、0. 000、0 .001)。结论:相对于FB常规放疗计划,在NSCLC精确放疗中使用ABC可以有效地减少周围型NSCLC正常组织的受照体积和剂量,减少肺和脊髓放射性损伤的发生率。

Active breathing control using in accurate radiotherapy of peripheral non-small cell lung cancer

OBJECTIVE:To evaluate the application in accurate radiotherapy of peripheral NSCLC using the active breathing control (ABC) and the effects in the reduction of radioactive lung and spinal cord damages. METHODS:Ten patients with peripheral NSCLC were included. For each patient, two CT scans were obtained with the general axial CT scans under free breathing (FB) and the fast spiral CT scans under ABC. Two treatment plans based on two CT scans were optimized. GTV, CTV, PTV, V_ 20 , D_ mean and spinal cord dose of the two plans were calculated and compared. RESULTS: Differences in GTV, CTV, PTV, V_ 20 , D_ mean and spinal cord dose between ABC and FB plans were significant, P <0.01 ( P =0.000 , 0.000, 0.000, 0.000, 0.000, 0.001), respectively. CONCLUSIONS: Compared with FB conditions, ABC in precise radiotherapy of peripheral NSCLC can decrease radiation volume and dose to the normal tissues as well as the probability of lung and spinal cord damages induced by radiation.