Choi Young Jun, Kim Ho Sung, Jahng Geon-Ho, Kim Sang Joon, Suh Dae Chul
Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul.
Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul
Acta Radiol. 2013 May;54(4):448-54. doi: 10.1177/0284185112474916. Epub 2013 Apr 30.
Pseudoprogression is a treatment-related reaction with an increase in contrast-enhancing lesion size, followed by subsequent improvement. Differentiating tumor recurrence from pseudoprogression remains a problem in neuro-oncology.
To validate the added value of arterial spin labeling (ASL), compared with dynamic susceptibility contrast (DSC) perfusion magnetic resonance imaging (MRI) alone, in distinguishing early tumor progression from pseudoprogression in patients with newly diagnosed glioblastoma multiforme (GBM).
We retrospectively evaluated 117 consecutive patients with newly diagnosed GBM who underwent surgical resection and concurrent chemoradiotherapy (CCRT) as standard treatment modality. Sixty-two patients who developed contrast-enhancing lesions were assessed by both ASL and DSC perfusion MRI and classified into groups of early tumor recurrence (n = 34) or pseudoprogression (n = 28) based on pathologic analysis or clinical-radiologic follow-up. We used a qualitative analysis and semi-quantitative grade system on the basis of the tumor perfusion signal intensity into those equal to white matter (grade I), gray matter (grade II), and blood vessels (grade III) on ASL imaging. ASL grade was correlated with histogram parameters derived from DSC perfusion MRI.
Pseudoprogression was observed in 15 (53.6%) patients with ASL grade I, 13 (46.4%) with grade II, and 0 (0%) with grade III, with early tumor progression observed in seven (20.6%) patients with ASL grade I, 11 (32.3%) with grade II, and 16 (47.1%) with grade III (P = 0.0022). DSC perfusion histogram parameters differed significantly among ASL grades. ASL grade was an independent predictor differentiating pseudoprogression from early tumor progression (odds ratio, 4.73; P = 0.0017). On qualitative review, adjunctive ASL produced eight (12.9%) more accurate results than DSC perfusion MRI alone.
ASL improves the diagnostic accuracy of DSC perfusion MRI in differentiating pseudoprogression from early tumor progression.
假性进展是一种与治疗相关的反应，表现为对比增强病灶大小增加，随后病情改善。在神经肿瘤学中，区分肿瘤复发与假性进展仍然是一个问题。
验证动脉自旋标记（ASL）与单独的动态磁敏感对比（DSC）灌注磁共振成像（MRI）相比，在区分新诊断的多形性胶质母细胞瘤（GBM）患者的早期肿瘤进展与假性进展方面的附加价值。
我们回顾性评估了117例连续的新诊断GBM患者，这些患者接受了手术切除和同步放化疗（CCRT）作为标准治疗方式。对62例出现对比增强病灶的患者进行了ASL和DSC灌注MRI评估，并根据病理分析或临床影像学随访分为早期肿瘤复发组（n = 34）或假性进展组（n = 28）。我们基于肿瘤灌注信号强度，在ASL成像上采用定性分析和半定量分级系统，将其分为等于白质（I级）、灰质（II级）和血管（III级）。ASL分级与从DSC灌注MRI得出的直方图参数相关。
在ASL I级的15例（53.6%）患者中观察到假性进展，II级的13例（46.4%）患者中观察到假性进展，III级的0例（0%）患者中观察到假性进展；在ASL I级的7例（约20.6%）患者中观察到早期肿瘤进展，II级的11例（32.3%）患者中观察到早期肿瘤进展，III级的16例（47.1%）患者中观察到早期肿瘤进展（P = 0.0022）。DSC灌注直方图参数在ASL各等级之间存在显著差异。ASL分级是区分假性进展与早期肿瘤进展的独立预测指标（优势比，4.73；P = 0.0017）。在定性评估中，辅助ASL比单独的DSC灌注MRI产生了多8例（12.9%）的准确结果。
ASL提高了DSC灌注MRI在区分假性进展与早期肿瘤进展方面的诊断准确性。
