Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-Gu, Seoul, 05505, South Korea.
Eur Radiol. 2019 Nov;29(11):5763-5771. doi: 10.1007/s00330-019-06200-0. Epub 2019 Apr 26.
To compare focal-type autoimmune pancreatitis (AIP) and pancreatic ductal adenocarcinoma (PDA) using contrast-enhanced MR imaging (CE-MRI), and to assess diagnostic performance of the lesion contrast at arterial phase (AP) (Contrast) for differentiating between the two diseases.
Thirty-six patients with focal-type AIP and 72 patients with PDA were included. All included patients underwent CE-MRI with triple phases. The signal intensity (SI) of the mass and normal pancreas was measured at each phase, and the lesion contrast (SI/SI) was compared between AIP and PDA groups. The sensitivity and specificity of Contrast using an optimal cutoff point were compared with those of key imaging features specific to AIP and PDA.
The lesion contrast differed significantly between AIP and PDA groups at all phases of CE-MRI; the maximum difference was observed at AP. For AIP, the sensitivity (94.4%) and specificity (87.5%) of Contrast (cutoff ≤ 1.41) were comparable or significantly higher than those of all key imaging features (sensitivity, 38.9-88.9%; specificity, 48.6-95.8%), except for the halo sign. For PDA, the sensitivity (87.5%) and specificity (94.4%) of Contrast (cutoff > 1.41) were comparable or significantly higher than those of all key imaging features (sensitivity, 40.3-68.1%; specificity, 72.2-94.4%), except for the discrete mass.
Quantitative analysis of the lesion contrast using CE-MRI, particularly at AP, was helpful to differentiate focal-type AIP from PDA. The diagnostic performance of Contrast was mostly comparable or higher than those of the key imaging features.
• Diagnosis of focal-type AIP vs. PDA using imaging techniques is extremely challenging. • Lesion contrast in the arterial-phase MRI differs significantly between focal-type AIP and PDA. • Quantitative analysis of lesion contrast using CE-MRI, particularly at the arterial phase, is helpful to differentiate focal-type AIP from PDA.
通过对比增强磁共振成像（CE-MRI）比较局灶型自身免疫性胰腺炎（AIP）和胰腺导管腺癌（PDA），评估动脉期（AP）病变对比（Contrast）对鉴别两种疾病的诊断性能。
纳入 36 例局灶型 AIP 患者和 72 例 PDA 患者。所有患者均行 CE-MRI 三期扫描。测量各期肿块与正常胰腺的信号强度（SI），比较 AIP 和 PDA 组之间的病灶对比（SI/SI）。采用最佳截断值比较 Contrast 的灵敏度和特异度与 AIP 和 PDA 特定的关键影像学特征的灵敏度和特异度。
CE-MRI 的所有期相均显示 AIP 和 PDA 组之间的病灶对比差异有统计学意义，最大差异出现在 AP 期。对于 AIP，Contrast（截断值≤1.41）的灵敏度（94.4%）和特异度（87.5%）与所有关键影像学特征（灵敏度 38.9-88.9%；特异度 48.6-95.8%）相当或更高，除晕环征外。对于 PDA，Contrast（截断值>1.41）的灵敏度（87.5%）和特异度（94.4%）与所有关键影像学特征（灵敏度 40.3-68.1%；特异度 72.2-94.4%）相当或更高，除离散肿块外。
CE-MRI 病变对比的定量分析，尤其是在 AP 期，有助于鉴别局灶型 AIP 和 PDA。Contrast 的诊断性能大多与关键影像学特征相当或更高。
使用影像学技术诊断局灶型 AIP 与 PDA 极具挑战性。
局灶型 AIP 和 PDA 的动脉期 MRI 病灶对比差异显著。
使用 CE-MRI 对病变对比进行定量分析，特别是在动脉期，有助于鉴别局灶型 AIP 和 PDA。
