gadoxetic-acid-disodium and Angiomyolipoma

Gadoxetic acid, a hepatocyte-specific magnetic resonance imaging (MRI) contrast agent, has emerged as an important tool for hepatocellular carcinoma (HCC) diagnosis. Gadoxetic acid-enhanced MRI is useful for the evaluation of earlystage HCC, diagnosis of HCC precursor lesions, and highly sensitive diagnosis of HCC. Furthermore, functional information provided by gadoxetic acid-enhanced MRI can aid in the characterization of focal liver lesions. For example, whereas lesions lack functioning hepatocytes appear hypointense in the hepatobiliary phase, preserved or enhanced expression of organic anion transporting polypeptides in some HCCs as well as focal nodular hyperplasia lead to hyperintensity in the hepatobiliary phase; and a targetoid appearance on transitional phase or hepatobiliary phase imaging can be helpful for identifying the histopathological composition of tumors. While gadoxetic acid-enhanced MRI may improve the sensitivity of HCC diagnosis and provide new insights into the characterization of focal liver lesions, there are many challenges associated with its use. This article reviews the pros and cons of HCC diagnosis with gadoxetic acid-enhanced MRI and discuss some clues in the radiological differentiation of HCC from HCC mimickers.

Topics: Angiomyolipoma; beta Catenin; Carcinoma, Hepatocellular; Contrast Media; Diagnosis, Differential; Gadolinium DTPA; Humans; Liver Neoplasms; Magnetic Resonance Imaging

Hepatocellular carcinoma is the most common primary hepatic malignant tumor. With widespread use of liver imaging, various cirrhosis-related nodules are frequently detected in patients with chronic liver disease, while diverse hypervascular hepatic lesions are incidentally detected but undiagnosed on dynamic computed tomography and magnetic resonance imaging (MRI). However, use of hepatocyte-specific MR contrast agents with combined perfusion and hepatocyte-selective properties have improved diagnostic performance in detection and characterization of focal liver lesions. Meanwhile, the enhancement patterns observed during dynamic phases using hepatocyte-specific agents may be different from those observed during MRI using conventional extracellular fluid agents, leading to confusion in diagnosis. Therefore, we discuss useful tips for the differentiation of hepatocellular carcinoma from similar lesions in patients with and without chronic liver disease using liver MRI with hepatocyte-specific agents.

Topics: Adenoma, Liver Cell; Angiomyolipoma; Bile Duct Neoplasms; Carcinoma, Hepatocellular; Cholangiocarcinoma; Contrast Media; Diagnosis, Differential; Focal Nodular Hyperplasia; Gadolinium DTPA; Hemangioma; Hepatocytes; Humans; Liver Cirrhosis; Liver Neoplasms; Magnetic Resonance Imaging

Functional imaging [diffusion-weighted imaging (DWI) and dynamic contrast enhancement (DCE)] techniques combined with T2-weighted (T2W) and chemical-shift imaging (CSI), with or without urography, constitutes a comprehensive multiparametric (MP) MRI protocol of the kidneys. MP-MRI of the kidneys can be performed in a time-efficient manner. Breath-hold sequences and parallel imaging should be used to reduce examination time and improve image quality. Increased T2 signal intensity (SI) in a solid renal nodule is specific for renal cell carcinoma (RCC); whereas, low T2 SI can be seen in RCC, angiomyolipoma (AML), and haemorrhagic cysts. Low b-value DWI can replace conventional fat-suppressed T2W. DWI can be performed free-breathing (FB) with two b-values to reduce acquisition time without compromising imaging quality. RCC demonstrates restricted diffusion; however, restricted diffusion is commonly seen in AML and in chronic haemorrhage. CSI must be performed using the correct echo combination at 3 T or T2* effects can mimic intra-lesional fat. Two-dimensional (2D)-CSI has better image quality compared to three-dimensional (3D)-CSI, but volume averaging in small lesions can simulate intra-lesional fat using 2D techniques. SI decrease on CSI is present in both AML and clear cell RCC. Verification of internal enhancement with MRI can be challenging and is improved with image subtraction. Subtraction imaging is prone to errors related to spatial misregistration, which is ameliorated with expiratory phase imaging. SI ratios can be used to confirm subtle internal enhancement and enhancement curves are predictive of RCC subtype. MR urography using conventional extracellular gadolinium must account for T2* effects; however, gadoxetic acid enhanced urography is an alternative. The purpose of this review it to highlight important technical and interpretive pearls and pitfalls encountered with MP-MRI of solid renal masses.

Topics: Angiomyolipoma; Carcinoma, Renal Cell; Contrast Media; Cysts; Diffusion Magnetic Resonance Imaging; Gadolinium DTPA; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Kidney; Kidney Neoplasms; Magnetic Resonance Imaging; ROC Curve; Sensitivity and Specificity

A 47-year-old Japanese man was referred to hospital after the detection of a liver tumor. Dynamic computed tomography and gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging were consistent with a diagnosis of hepatocellular carcinoma (HCC). No perfusion defect was observed in the post-vascular phase of contrast-enhanced ultrasound (CEUS). Histopathological staining of the tumor cells was positive for antibodies against HMB-45 and cluster of differentiation (CD) 68, confirming the diagnosis of hepatic angiomyolipoma (HAML). These findings indicated the presence of macrophages in HAML. We herein report a case of HAML explain how macrophages that are present within the tumor affect the staining characteristics in the post-vascular phase of CEUS.

Topics: Angiomyolipoma; Contrast Media; Diagnosis, Differential; Female; Gadolinium DTPA; Humans; Liver Neoplasms; Macrophages; Magnetic Resonance Imaging; Male; Middle Aged; Staining and Labeling

Hepatic angiomyolipomas are a rare, benign group of mesenchymal tumors in the liver. Hepatic angiomyolipoma is sometimes misdiagnosed as hepatocellular carcinoma, and there is the possibility of a malignant transformation. Hence, the accurate diagnosis of this disorder is necessary.. A 64-year-old Japanese man was observed to have a space-occupying lesion of 15-mm diameter in the liver during a follow-up examination for a previously resected cecal carcinoma. He underwent lateral segmentectomy of the liver with a provisional diagnosis of hepatic metastatic recurrence of the carcinoma based on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging and diffusion-weighted imaging.. We have explored the combination of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging and histological examination to confirm our diagnosis of hepatic angiomyolipoma comprising an intimate mixture of numerous abnormal blood vessels, adipocytes, and epithelioid spindle cells of various sizes. Immunohistochemical examination revealed characteristic pathological findings associated with positive qualitative immunoreactions for human melanoma black 45 and desmin. Electron microscopic findings revealed the presence of melanosomes in the epithelioid cells. Diffusion-weighted imaging provides a more accurate diagnostic image with the characteristic macroscopic appearance of hepatic angiomyolipoma. Through immunohistochemistry and electron microscopy, we also show that this benign tumor comprises tissue elements.

Topics: Angiomyolipoma; Carcinoma, Hepatocellular; Contrast Media; Gadolinium DTPA; Humans; Immunohistochemistry; Liver; Liver Neoplasms; Magnetic Resonance Imaging; Male; Microscopy, Electron, Transmission; Middle Aged; Treatment Outcome

The purpose of this study is to describe the imaging characteristics of hepatic angiomyolipoma (AML) on gadoxetic acid-enhanced MRI and to identify imaging features that are helpful for differentiating it from hepatocellular carcinoma (HCC) in a noncirrhotic liver.. We retrospectively identified 18 patients with pathologically proven hepatic AMLs who had undergone gadoxetic acid-enhanced MRI between 2008 and 2012. We randomly chose 36 patients with noncirrhotic liver who had a single HCC diagnosed radiologically during the same period. None of the HCCs was of the fibrolamellar variant. Two readers reviewed images in consensus to assess the lesion size, the presence of fat, signal intensity characteristics, enhancement profile, early draining veins, intratumoral vessels, and tumor capsules. The tumor-to-liver contrast ratios were measured. These features and the measurements were compared between the two groups.. AMLs are more commonly found in women (83.3%), whereas HCCs are more common in men (75%) (p < 0.01). The size of AMLs (3.4 cm) and HCCs (4.3 cm) did not differ significantly. Intratumoral fat was identified in both AMLs (50.0%) and HCCs (30.6%). The dynamic enhancement profile (arterial hypervascularity and hypointensity during the delayed phase) was similar qualitatively and quantitatively except for the portal phase. AMLs and HCCs differed significantly with regard to isointensity on DWI (16.7% vs 0.0%; p = 0.03), washout in the portal phase (61.1% vs 88.9%; p = 0.03), early draining veins (27.8% vs 2.8%; p = 0.01), intratumoral vessels (55.6% vs 22.2%; p = 0.03), and presence of capsule (11.1% vs 50.0%; p = 0.01).. On gadoxetic acid-enhanced MRI of noncirrhotic liver, AML is often indistinguishable from HCC on the basis of the enhancement profiles. Female sex and some imaging features including DWI could facilitate the differentiation.

Topics: Adult; Aged; Angiomyolipoma; Carcinoma, Hepatocellular; Contrast Media; Diagnosis, Differential; Female; Gadolinium DTPA; Humans; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged

To investigate magnetic resonance (MR) findings of angiomyolipoma (AML) on gadoxetic acid-enhanced MR imaging, and to identify features that differentiate AML from hepatocellular carcinoma (HCC) in patients with a low risk of HCC development.. This retrospective study was institutional review board approved, and the requirement for informed consent was waived. Twelve patients with hepatic AML who underwent gadoxetic acid-enhanced MRI with no risk factors for HCC development were recruited. Twenty-seven patients with HCC under the same inclusion criteria were recruited as control. Two radiologists analyzed the images in consensus for morphologic features, enhancement patterns, and hepatobiliary phase (HBP) findings. All results were analyzed using the Mann-Whitney test, two-tailed Fisher exact test, and chi-square test.. Patients with AML were younger than those with HCC (48.8 ± 15 years for AML vs. 62.7 ± 14.2 years for HCC, p = 0.008) with female predominance, while most HCC patients were male (75% (9/12) vs. 15% (4/27), p < 0.001). The most prevalent enhancement pattern was arterial enhancement followed by hypointensity at portal or transitional phases for both AMLs (58% (7/12)) and HCCs (74% (20/27)) (p = 0.455). However, during the HBP, AMLs frequently showed more homogeneous hypointensity than HCCs (83% (10/12) vs. 41% (11/27), p = 0.018). When compared with the signal intensity of the spleen, the mean relative signal intensity of the AML was 91.2 ± 15.4%, while in HCCs, it was 128.7 ± 40% (p < 0.001).. Although AMLs showed similar enhancement patterns to HCCs during the dynamic phases of gadoxetic acid-enhanced MRI, using characteristic MR features of AML during the HBP and demographic differences, one can better differentiate AML from HCC.

Topics: Adult; Aged; Angiomyolipoma; Contrast Media; Diagnosis, Differential; Female; Gadolinium DTPA; Humans; Image Enhancement; Image Processing, Computer-Assisted; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Retrospective Studies

Topics: Adenoma, Bile Duct; Adult; Aged; Angiomyolipoma; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Carcinoma, Hepatocellular; Diagnosis, Differential; Female; Gadolinium DTPA; Humans; Liver Diseases; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Pseudolymphoma; Tomography, X-Ray Computed