CT灌注成像对非小细胞肺癌放疗靶区确定的临床意义

目的探讨CT灌注成像扫描对非小细胞肺癌（NSCLC）行三维适形放疗（3DCRT）时靶区确定的临床意义。方法对36例经病理组织学检查证实为NSCLC患者,先后行胸部常规CT扫描及CT灌注成像扫描。根据成像勾画原发病灶范围,分别称为CT-GTV和CTPI-CTV,由三维治疗计划系统得出GTV具体数值进行比较。结果所有患者均有不同程度差别。CT-GTV平均为133.00cm^3（90～194cm^3）,CTPI-CTV平均为106.60cm^3（67～152cm^3）;CTPI-CTV较CT-GTV缩小19.8%（26.4cm^3）（P=0.00）。GTV减少的主要原因是CT灌注成像能辨别肺不张和肿瘤,因而可以减少肿瘤靶体积并且避免正常组织不必要的勾画。结论CT灌注成像在确定非小细胞肺癌3DCRT靶区方面具有一定临床价值,并由此提高了靶区定位的精确性。

The Value of CT Perfusion Imaging in The Target Delineation in Patients With Non-small Cell Lung Cancer

Objective To investigate the potential benefit of using CT perfusion imaging to delineate the gross tumor volume（GTV） in patients with non - small cell lung cancer（NSCLC） who were to be treated with three - dimensional conformal radiation therapy（3DCRT）. Methods 36 patients with histologically proven NSCLC were studied. All patients were scanned with both thoracic CT and CT perfnsion imaging. The GTV was contoured based on both CT image （ CT - GTV） and CT perfusion image （ CTPI - CTV）. The volumes of GTV obtained from 3 dimensional treatment planning system were compared. Results The volumes were different between every paired CT - GTV and CTPI - CTV. As a whole, the patients GTV was reduced by 19.8% （26.4 cm^3 ） with median CT - GTV of 133 cm^3 （90 - 194 cm^3 ） and median CTPI - CTV of 106.6 cm^3 （ 67 - 152 cm^3 ） （ P = 0.00）. The reduction of CTPI - CTV was due to differentiation of atelectasis from gross tumor by CT perfusion imaging, which helped reduce the target volume and spared more surrounding normal tissue. Conclusion The CT perfusion imaging might be helpful in the target delineation in patients with non small cell lung cancer.