Department of Radiation Oncology & Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA.
Future Oncol. 2014 May;10(7):1277-97. doi: 10.2217/fon.13.271.
A familiar challenge for neuroradiologists and neuro-oncologists is differentiating between radiation treatment effect and disease progression in the CNS. Both entities are characterized by an increase in contrast enhancement on MRI and present with similar clinical signs and symptoms that may occur either in close temporal proximity to the treatment or later in the disease course. When radiation-related imaging changes or clinical deterioration are mistaken for disease progression, patients may be subject to unnecessary surgery and/or a change from otherwise effective therapy. Similarly, when disease progression is mistaken for treatment effect, a potentially ineffective therapy may be continued in the face of progressive disease. Here we describe the three types of radiation injury to the brain based on the time to development of signs and symptoms--acute, subacute and late--and then review specific imaging changes after intensity-modulated radiation therapy, stereotactic radiosurgery and brachytherapy. We provide an overview of these phenomena in the treatment of a wide range of malignant and benign CNS illnesses. Finally, we review the published data regarding imaging techniques under investigation to address this well-known problem.
神经放射学家和神经肿瘤学家面临的一个常见挑战是区分中枢神经系统（CNS）中的放射治疗效果和疾病进展。这两种情况的特点是 MRI 上对比增强增加，并伴有相似的临床症状和体征，这些症状和体征可能发生在治疗后接近的时间内，也可能发生在疾病过程的后期。当与放射治疗相关的影像学改变或临床恶化被误认为是疾病进展时，患者可能会接受不必要的手术和/或改变原本有效的治疗方法。同样，当疾病进展被误认为是治疗效果时，在疾病进展的情况下，可能会继续使用潜在无效的治疗方法。在这里，我们根据症状出现的时间描述了脑放射损伤的三种类型——急性、亚急性和迟发性，然后回顾了调强放疗、立体定向放疗和近距离放疗后的特定影像学改变。我们概述了这些现象在治疗各种良恶性 CNS 疾病中的应用。最后，我们回顾了目前正在研究的成像技术的相关数据，以解决这一众所周知的问题。
