Importance of small (< or = 20-mm) enhancing lesions seen only during the hepatic arterial phase at MR imaging of the cirrhotic liver: evaluation and comparison with whole explanted liver.
Importance of small (< or = 20-mm) enhancing lesions seen only during the hepatic arterial phase at MR imaging of the cirrhotic liver: evaluation and comparison with whole explanted liver.
复制标题
肝硬化肝脏 MR 成像中仅在肝动脉期可见的小（< 或 = 20 毫米）增强病变的重要性：与整个移植肝脏的评估和比较。
作者：
A. Holland;E. Hecht;W. Hahn;W. Hahn;Daniel Kim;J. Babb;V. Lee;A. West;G. Krinsky
目的
回顾性评估在门脉期和/或平衡期以及在未增强的T1和T2加权磁共振（MR）成像中隐匿的小（直径≤ 20 mm）肝动脉期增强（HAPE）病变的重要性和影像学表现，并通过全肝移植比较确定大体病理诊断。
材料和方法
这项回顾性研究得到了机构审查委员会的批准，符合HIPPA。对46例在90天内接受MR成像和移植的肝硬化患者进行了1.5 T屏气T2加权和体积三维钆增强梯度回波MR成像，包括肝动脉、门静脉和平衡期。三名对病理结果不知情的阅片者回顾性审查了MR图像，一致认为T2加权及门脉期和/或平衡期MR成像中隐藏的小HAPE结节。只有动脉期结节增强的患者被纳入最终研究组，其中包括16名患者（12名男性和4名女性），年龄18-66岁（中位年龄51.5岁）。将移植的肝脏连续切成5-8 mm厚的切片，以评价发育不良结节和肝细胞癌（HCC）。进行Fisher精确检验以确定HCC和仅HAPE肿瘤性病变之间是否存在关系。使用Mann-Whitney检验来确定具有至少一个肿瘤性仅HAPE病变的患者是否具有更多数量的非仅HAPE病变。
结果
这16名患者有45个HAPE病变;其中3个（7%）是肿瘤性的，包括1个明显的HCC，1个HCC出现在发育不良结节中，1个发育不良结节。其余42例仅HAPE病变（93%）均无相关病理结果。所有三个肿瘤性病变只在动脉期被发现在8例合并HCC，谁也有额外的13个病理证实的非肿瘤性HAPE只有病变。在8例无HCC的患者中，仅HAPE病变均为肿瘤性。伴随的非HAPE肿瘤性病变不是存在至少一个肿瘤性HAPE病变的显著（P = 0.2）预测因子。初步但不显著（P = 0.13）的迹象表明，仅肿瘤性HAPE病变患者的非仅HAPE病变数量往往更高。
结论
大多数（93%）在T2加权及门脉期和/或平衡期MR成像中隐匿的HAPE病灶是非肿瘤性的，即使在病理证实的HCC患者中也是如此。
PURPOSE
To retrospectively assess the importance and imaging appearance of small (< or = 20 mm in diameter) hepatic arterial phase-enhancing (HAPE) lesions that are occult during portal and/or equilibrium phases and at unenhanced T1- and T2-weighted magnetic resonance (MR) imaging and to determine the gross pathologic diagnosis with whole-liver explant comparison.
MATERIALS AND METHODS
This retrospective study was approved by the institutional review board and compliant with HIPPA. Forty-six patients with cirrhosis who underwent MR imaging and transplantation within 90 days were evaluated with breath-hold T2-weighted and volumetric three-dimensional gadolinium-enhanced gradient-echo MR imaging in the hepatic arterial, portal venous, and equilibrium phases at 1.5 T. Three readers, who were blinded to the pathologic results, retrospectively reviewed the MR images in consensus for small HAPE nodules that were occult at T2-weighted and portal and/or equilibrium phase MR imaging. Only patients with nodules that enhanced during the arterial phase were included in the final study group, which included 16 patients (12 men and four women) aged 18-66 years (median age, 51.5 years). Explanted livers were serially sliced into 5-8-mm-thick sections to evaluate dysplastic nodules and hepatocellular carcinomas (HCCs). The Fisher exact test was performed to determine whether there was a relationship between HCC and the presence of a neoplastic HAPE-only lesion. The Mann-Whitney test was used to determine if patients with at least one neoplastic HAPE-only lesion had a larger number of non-HAPE-only lesions.
RESULTS
The 16 patients had 45 HAPE-only lesions; three (7%) of which were neoplastic, including one overt HCC, one HCC arising in a dysplastic nodule, and one dysplastic nodule. None of the remaining 42 HAPE-only lesions (93%) had correlative pathologic findings. All three neoplastic lesions seen only during the arterial phase were found in eight patients with concomitant HCC, who also had an additional 13 pathologically proved nonneoplastic HAPE-only lesions. In eight patients without HCC, none of the HAPE-only lesions were neoplastic. A concomitant non-HAPE-only neoplastic lesion was not a significant (P = .2) predictor for the presence of at least one neoplastic HAPE-only lesion. There was a preliminary but insignificant (P = .13) indication that the number of non-HAPE-only lesions tends to be higher in patients with neoplastic HAPE-only lesions.
CONCLUSION
The majority (93%) of HAPE-only lesions that are occult at T2-weighted and portal and/or equilibrium phase MR imaging are nonneoplastic, even in patients with pathologically proved HCC.