Jeong Daniel, Malalis Christian, Arrington John A, Field Aaron S, Choi Jung W, Kocak Mehmet
1 Department of Radiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA ; 2 Department of Diagnostic Radiology, Rush University Medical Center, Chicago, IL, USA ; 3 Department of Radiology, University of Wisconsin-Madison, Madison, WI, USA.
Quant Imaging Med Surg. 2015 Dec;5(6):835-45. doi: 10.3978/j.issn.2223-4292.2015.12.05.
To evaluate mean apparent diffusion coefficient (ADC) values on pre-radiotherapy magnetic resonance (MR) at sites that gave rise to glioblastoma (GBM) recurrence compared to similar surrounding background tissue that did not progress to tumor.
Twenty out of 110 consecutive patients with pathology proven GBM treated at our institution from 1/1/2009 to 5/31/2012 had definitive recurrence 6 months following radiotherapy. In this single-center retrospective cohort study, pre- and post-radiotherapy MR brain exams were evaluated. Sites of tumor recurrence on post-therapy exams were co-localized to pre-therapy exams and the background tissue type which gave rise to tumor was noted (i.e., T2 hyperintensity, normal appearing white or gray matter). Similar surrounding background tissue not progressing to tumor was also selected. Two radiologists compared mean ADC values on pre-radiotherapy MR for sites which gave rise to future tumor recurrence and sites of similar background tissue.
Pre-radiotherapy mean ADC values were significantly lower in regions of future tumor recurrence than in regions of surrounding background tissue not progressing to tumor (P=0.003). There were no significant quantitative differences on T1-weighted pre contrast (P=0.50) or T2-weighted (P=0.10) sequences between sites. There was strong interobserver agreement with an intraclass correlation of 0.867 for ADC values at sites of future tumor recurrence and background tissue.
Mean ADC values may help predict sites of future gross tumor recurrence in GBM, which could be helpful in radiation therapy planning.
评估胶质母细胞瘤（GBM）复发部位放疗前磁共振成像（MR）的平均表观扩散系数（ADC）值，并与未进展为肿瘤的相似周围背景组织进行比较。
2009年1月1日至2012年5月31日在本机构接受治疗的110例经病理证实的GBM连续患者中，有20例在放疗后6个月出现明确复发。在这项单中心回顾性队列研究中，对放疗前后的脑部MR检查进行了评估。将治疗后检查中肿瘤复发部位与治疗前检查进行共定位，并记录引发肿瘤的背景组织类型（即T2高信号、外观正常的白质或灰质）。还选择了未进展为肿瘤的相似周围背景组织。两名放射科医生比较了放疗前MR上未来肿瘤复发部位和相似背景组织部位的平均ADC值。
未来肿瘤复发区域放疗前的平均ADC值显著低于未进展为肿瘤的周围背景组织区域（P = 0.003）。各部位在T1加权平扫（P = 0.50）或T2加权（P = 0.10）序列上无显著定量差异。观察者间一致性很强，未来肿瘤复发部位和背景组织部位ADC值的组内相关系数为0.867。
平均ADC值可能有助于预测GBM未来大体肿瘤复发部位，这对放射治疗计划可能有帮助。
