From the Department of Radiology, Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, South Korea (M.H.Y., J.H.K., J.H.Y., H.C.K., J.W.C., J.K.H., B.I.C.); and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, South Korea (J.W.C., J.K.H., B.I.C.).
Radiology. 2014 Jun;271(3):748-60. doi: 10.1148/radiol.14131996. Epub 2014 Feb 1.
To assess diagnostic performance and imaging features of gadoxetic acid-enhanced magnetic resonance (MR) imaging in small (≤1-cm) hepatocellular carcinoma (HCC) detection in patients with chronic liver disease.
The institutional review board approved this retrospective study and waived informed consent. Sixty patients (56 men, four women; mean age, 60.1 years) with HCC (146 lesions; 70 > 1 cm, 76 ≤ 1 cm) underwent gadoxetic acid-enhanced MR imaging. HCC was confirmed at surgical resection (72 lesions; 30 > 1 cm, 42 ≤ 1 cm) or by showing interval growth with typical enhancement patterns at follow-up dynamic computed tomography or MR imaging (74 lesions; 40 > 1 cm, 34 ≤ 1 cm). Two radiologists assessed MR imaging features and graded likelihood of HCC with a five-point confidence scale. Jackknife alternative free-response receiver operating characteristic (JAFROC) method was used.
Mean JAFROC figure of merit for small HCC was 0.717; that for large (>1-cm) HCC was 0.973 with substantial agreement (κ = 0.676). Mean sensitivity and positive predictive value (PPV) were 46.0% (70 of 152) and 48.3% (70 of 145) for small HCC versus 95.0% (133 of 140) and 78.2% (133 of 170) for large HCC, respectively. Eleven of 76 small HCCs (14%) were not seen on MR images, even after careful investigation. MR imaging features of small HCC included arterial enhancement (79%, 60 of 76), hypointensity on hepatobiliary phase (HBP) images (68%, 52 of 76), washout on 3-minute delayed phase images (50%, 38 of 76), hyperintensity on T2-weighted images (43%, 33 of 76), hypointensity on T1-weighted images (32%, 24 of 76), and restriction on diffusion-weighted images (28%, 20 of 72). Arterial enhancement and washout on 3-minute delayed phase images or hypointensity on HBP images occurred in 66% of small HCCs (50 of 76).
Diagnostic performance of gadoxetic acid-enhanced MR imaging for small HCC detection is still low, with mean sensitivity of 46.0% (70 of 152) and mean PPV of 48.3% (70 of 145). By adding hypointensity on HBP images as washout, diagnostic performance for small HCC detection can be improved.
评估钆塞酸增强磁共振成像（MR）在检测慢性肝病患者小（≤1cm）肝细胞癌（HCC）中的诊断性能和影像学特征。
本回顾性研究经机构审查委员会批准，并豁免了知情同意。60 名患者（56 名男性，4 名女性；平均年龄 60.1 岁）患有 HCC（146 个病灶；70 个病灶＞1cm，76 个病灶≤1cm），接受了钆塞酸增强 MR 成像检查。HCC 在手术切除时得到证实（72 个病灶；30 个病灶＞1cm，42 个病灶≤1cm），或通过在随访的动态 CT 或 MR 成像上显示出具有典型强化模式的间隔生长得到证实（74 个病灶；40 个病灶＞1cm，34 个病灶≤1cm）。两名放射科医生使用五分制置信度量表评估 MR 成像特征并分级 HCC 的可能性。采用 Jackknife 替代自由响应接收器操作特征（JAFROC）方法。
小 HCC 的平均 JAFROC 表现得分为 0.717；大（＞1cm）HCC 的得分为 0.973，具有显著一致性（κ=0.676）。小 HCC 的平均敏感度和阳性预测值（PPV）分别为 46.0%（70/152）和 48.3%（70/145），而大 HCC 分别为 95.0%（133/140）和 78.2%（133/170）。76 个小 HCC 中有 11 个（14%）在 MR 图像上无法看到，即使经过仔细检查也是如此。小 HCC 的 MR 成像特征包括动脉期强化（79%，60/76）、肝胆期（HBP）图像低信号（68%，52/76）、3 分钟延迟期图像洗脱（50%，38/76）、T2 加权图像高信号（43%，33/76）、T1 加权图像低信号（32%，24/76）和扩散加权图像受限（28%，20/72）。在 66%的小 HCC 中（50/76）出现动脉期强化和 3 分钟延迟期图像洗脱或 HBP 图像低信号。
钆塞酸增强 MR 成像在小 HCC 检测中的诊断性能仍然较低，平均敏感度为 46.0%（70/152），平均 PPV 为 48.3%（70/145）。通过添加 HBP 图像上的低信号作为洗脱，可提高小 HCC 检测的诊断性能。
