应用DWI指导胶质瘤放疗靶区勾画的初步研究

Primary Study of DWI in the Delineation of Radiotherapy Target Volume of Glioma

目的:高级别胶质瘤中的间变性星形细胞瘤(AA)(WHO III级)和胶质母细胞瘤(GBM)(WHO IV级)预后差别大,但放疗靶区的设定未进一步细分,本研究通过弥散加权成像(DWI)对肿瘤及周围区域进行研究,探讨两者术后放疗靶区勾画的差异。方法:对我院收治的高级别胶质瘤术后残留患者入组,放疗前行DWI检查,测量肿瘤区、近瘤周区、中瘤周区、远瘤周区及瘤周区外的表观弥散系数(ADC)值。结果:2013年9月至2014年12月,共76例患者入组,其中24例AA,52例GBM。AA的ADC值在近瘤周区最大;GBM的ADC值在中瘤周区最大。在肿瘤区、中瘤周区和远瘤周区,AA和GBM的ADC值(包括最小值和平均值)均有统计学差异;在瘤周区外,两组无显著差异。结论 :DWI及ADC值有助于指导胶质瘤术后放疗靶区的勾画。

Purpose： The prognosis of anaplastic astrocytoma （AA） and glioblastoma （GBM） is different, but the treatment in radiotherapy is not further refined. This study was to explore the values of DWI in the delineation of radiotherapy target volume for the post-operative AA and GBM patients. Methods：： The post-operative high grade glioma （HGG） patients with residual tumor were included in this prospective study. All patients were performed MRI with DWI sequence before radiotherapy. The values of ADC were measured in residual tumor, peritumoral tissue and the corresponding normal tissue. The perittunoral tissue is divided into four areas： the proximal area; the middle area; the distal area; the outside area. Results： From Sep. 2013 to Dec. 2014, 76 patients were included. There were 24 cases AA and 52 cases GBM. The ADC values reached maximum in the proximal area of the group AA, but the group GBM was in the middle area. In addition to the proximal area and the outside area, the differences of the ADC between two groups were with statistical significant in the rest areas. Couclusion： DWI and the ADC values could present valuable information for target delineation for HGG after operation.