Division of Neuroradiology, Department of Radiology, Henry Ford Health System, Detroit, MI 48202, USA.
Neuro Oncol. 2011 Sep;13(9):1037-46. doi: 10.1093/neuonc/nor075. Epub 2011 Jul 29.
Differentiating treatment-induced necrosis (TIN) from recurrent/progressive tumor (RPT) in brain tumor patients using conventional morphologic imaging features is a very challenging task. Functional imaging techniques also offer moderate success due to the complexity of the tissue microenvironment and the inherent limitation of the various modalities and techniques. The purpose of this retrospective study was to assess the utility of nonmodel-based semiquantitative indices derived from dynamic contrast-enhanced T1-weighted MR perfusion (DCET1MRP) in differentiating TIN from RPT. Twenty-nine patients with previously treated brain tumors who showed recurrent or progressive enhancing lesion on follow-up MRI underwent DCET1MRP. Another 8 patients with treatment-naive high-grade gliomas who also underwent DCET1MRP were included as the control group. Semiquantitative indices derived from DCET1MRP included maximum slope of enhancement in initial vascular phase (MSIVP), normalized MSIVP (nMSIVP), normalized slope of delayed equilibrium phase (nSDEP), and initial area under the time-intensity curve (IAUC) at 60 and 120 s (IAUC(60) and IAUC(120)) obtained from the enhancement curve. There was a statistically significant difference between the 2 groups (P < .01), with the RPT group showing higher MSIVP (15.78 vs 8.06), nMSIVP (0.046 vs 0.028), nIAUC(60) (33.07 vs 6.44), and nIAUC(120) (80.14 vs 65.55) compared with the TIN group. nSDEP was significantly lower in the RPT group (7.20 × 10(-5) vs 15.35 × 10(-5)) compared with the TIN group. Analysis of the receiver-operating-characteristic curve showed nMSIVP to be the best single predictor of RPT, with very high (95%) sensitivity and high (78%) specificity. Thus, nonmodel-based semiquantitative indices derived from DCET1MRP that are relatively easy to derive and do not require a complex model-based approach may aid in differentiating RPT from TIN and can be used as robust noninvasive imaging biomarkers.
利用常规形态学成像特征区分脑肿瘤患者的治疗诱导性坏死（TIN）和复发性/进展性肿瘤（RPT）是一项极具挑战性的任务。由于组织微环境的复杂性以及各种模态和技术的固有局限性，功能成像技术的成功率也相当有限。本回顾性研究的目的是评估源自动态对比增强 T1 加权磁共振灌注（DCET1MRP）的非模型基半定量指标在区分 TIN 与 RPT 方面的效用。29 例经治疗的脑肿瘤患者在随访 MRI 上显示复发性或进行性强化病灶，行 DCET1MRP 检查。另 8 例经治疗的高级别胶质瘤患者，行 DCET1MRP 检查作为对照组。源自 DCET1MRP 的半定量指标包括初始血管相最大强化斜率（MSIVP）、归一化 MSIVP（nMSIVP）、延迟平衡相归一化斜率（nSDEP）以及 60 和 120 秒时强化曲线下初始面积（IAUC）（IAUC(60) 和 IAUC(120)）。两组间存在统计学差异（P＜.01），RPT 组的 MSIVP（15.78 比 8.06）、nMSIVP（0.046 比 0.028）、nIAUC(60)（33.07 比 6.44）和 nIAUC(120)（80.14 比 65.55）均显著高于 TIN 组。RPT 组的 nSDEP 明显低于 TIN 组（7.20×10(-5) 比 15.35×10(-5)）。受试者工作特征曲线分析表明，nMSIVP 是 RPT 的最佳单项预测指标，具有非常高（95%）的灵敏度和高（78%）的特异性。因此，源自 DCET1MRP 的非模型基半定量指标相对容易获得，且不需要复杂的基于模型的方法，有助于区分 RPT 与 TIN，可作为可靠的无创成像生物标志物。
