Ozaki Kumi, Yoneda Norihide, Harada Kenichi, Ikeno Hiroshi, Takahashi Misa, Kaizaki Yasuharu, Maeda Kazuya, Higuchi Shohei, Takata Kenji, Gabata Toshifumi
Departments of Radiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
Department of Radiology, Hamamatsu University School of Medicine, Hamamatsu, Japan.
Radiol Case Rep. 2023 Jun 22;18(9):3093-3100. doi: 10.1016/j.radcr.2023.05.049. eCollection 2023 Sep.
Focal nodular hyperplasia (FNH) or FNH-like lesions of the liver are benign lesions that can be mostly diagnosed by hepatobiliary phase gadoxetic acid-enhanced magnetic resonance imaging (MRI). Accurate imaging diagnosis is based on the fact that most FNHs or FNH-like lesions show characteristic hyper- or isointensity on hepatobiliary phase images. We report a case of an FNH-like lesion in a 73-year-old woman that mimicked a malignant tumor. Dynamic contrast-enhanced computed tomography (CT) and MRI using gadoxetic-acid revealed an ill-defined nodule showing early enhancement in the arterial phase and gradual and prolonged enhancement in the portal and equilibrium/transitional phases. Hepatobiliary phase imaging revealed inhomogeneous hypointensity, accompanied by a slightly isointense area compared to the background liver. Angiography-assisted CT showed a portal perfusion defect of the nodule, inhomogeneous arterial blood supply in the early phase, and less internal enhancement in the late phase, accompanied by irregularly shaped peritumoral enhancement. No central stellate scar was identified in any of the images. Imaging findings could not exclude the possibility of hepatocellular carcinoma, but the nodule was pathologically diagnosed as an FNH-like lesion by partial hepatectomy. In the present case, an unusual inhomogeneous hypointensity on hepatobiliary phase imaging made it difficult to diagnose the FNH-like lesions.
肝脏局灶性结节性增生（FNH）或FNH样病变是良性病变，大多可通过肝胆期钆塞酸增强磁共振成像（MRI）进行诊断。准确的影像诊断基于大多数FNH或FNH样病变在肝胆期图像上表现出特征性的高信号或等信号这一事实。我们报告一例73岁女性的FNH样病变，该病变酷似恶性肿瘤。动态对比增强计算机断层扫描（CT）和使用钆塞酸的MRI显示一个边界不清的结节，在动脉期呈早期强化，在门静脉期和平衡/过渡期呈逐渐且持续的强化。肝胆期成像显示不均匀低信号，与背景肝脏相比伴有一个稍等信号区。血管造影辅助CT显示该结节有门静脉灌注缺损，早期动脉血供不均匀，晚期内部强化较少，伴有瘤周不规则形强化。在任何图像中均未发现中央星状瘢痕。影像表现不能排除肝细胞癌的可能性，但通过部分肝切除术，该结节病理诊断为FNH样病变。在本病例中，肝胆期成像上不寻常的不均匀低信号使得FNH样病变难以诊断。
