Small hypervascular hepatocellular carcinomas: value of “washout” on gadolinium-enhanced dynamic MR imaging compared to superparamagnetic iron oxide-enhanced imaging

Abstract

The aim of this study was to retrospectively compare the value of "washout" on dynamic MR imaging with superparamagnetic iron oxide (SPIO)-enhanced imaging features of small hepatocellular carcinoma (HCC). A total of 74 small (5-30 mm) hypervascular HCCs in 42 cirrhotic patients who underwent double contrast material-enhanced MR imaging were evaluated to determine the presence of washout in the portal or equilibrium phase of gadolinium-enhanced dynamic imaging and decreased uptake of SPIO on T2*-weighted imaging. HCCs were verified histologically (n = 13) or by serial follow-up imaging studies (n = 61). According to the size of the lesions, 27 vs. 73% (<10 mm, n = 15; P = 0.016 on McNemar test), 39 vs. 79% (10-14 mm, n = 28; P = 0.002), 50 vs. 93% (15-20 mm, n = 14; P = 0.031), and 82 vs. 100% (>20 mm, n = 17; P = 0.250) of the lesions showed washout vs. decreased SPIO accumulation respectively. The larger the lesion, the higher the prevalence of washout or decreased SPIO uptake (P = 0.004 or P = 0.036, respectively, on Mantel-Haenszel test). In many small hypervascular HCCs up to 2 cm, SPIO-enhanced MR imaging offers essential information for early diagnosis in the absence of washout on dynamic imaging.

Small (≤2 cm) hepatocellular carcinoma in patients with chronic liver disease: comparison of gadoxetic acid-enhanced 3.0 T MRI and multiphasic 64-multirow detector CT

“…In clinical practice, although HCCs .2 cm usually show the typical enhancement pattern (i.e. hypervascular at arterial phase and washout at portal or equilibrium phase) of HCC on dynamic CT or MRI, this is not always the case for HCCs ,2 cm, based on previous reports [5,[35][36][37][38] and our study. Furthermore, small nodular arterial enhancing pseudolesions such as arterioportal shunt are frequently encountered in cirrhotic liver, which is a major mimicker of small HCCs.…”

Comparison of Portal Venous and Delayed Phases of Gadolinium-Enhanced Magnetic Resonance Imaging Study of Cirrhotic Liver for the Detection of Contrast Washout of Hypervascular Hepatocellular Carcinoma

“…11,33 Furthermore, it has been suggested that superparamagnetic iron oxideYenhanced MRI could help in the early diagnosis of HCC when small hypervascular lesions without evidence of venous washout are detected at dynamic imaging. 34 Some limitations of our study need to be addressed, besides its retrospective nature. Among them, the small patient population, the lack of pathological proof for all nodules believed to be HCC, and the lack of analysis of lesions other than HCC detected on the MR images may be overcome by studies conducted on a large cohort of consecutive liver-transplanted patients.…”

Validation of Contrast-Enhanced Magnetic Resonance Imaging to Monitor Regenerative Efficacy After Cell Therapy in a Porcine Model of Convalescent Myocardial Infarction

“…An interim MRI analysis of the still-ongoing SCIPIO trial (where MRI was performed only in treated, primarily non-randomized patients) showed similar results 4 . Although late Gd-enhanced cardiac MRI has been extensively validated for the quantification of necrotic/fibrotic and viable myocardium in acute/chronic MI 6-8 , its validity to accurately characterize tissue viability after cell therapy has been questioned 10 : cell administration may increase vascular wall thickness, resulting in decreased vessel permeability and attenuation of Gd-contrast extravasation in cell-treated myocardial regions, or stimulate angiogenesis, leading to enhanced drainage of Gd-contrast from the cell-treated myocardium (a phenomenon that has been described in hypervascular hepatocellular carcinomas 11 ). Any of these confounding factors, if operative, would result in altered Gd-contrast myocardial kinetics (in the form of decreased contrast extravasation or accelerated wash-out) that could compromise the fidelity of contrast-enhanced MRI 10 .…”

“…However, its validity in characterizing tissue viability after cell administration has been called into question 10 . Without evidence, concerns have been raised that cell therapy may promote changes in vessel density or architecture (e.g., increase in wall thickness or decrease in vascular permeability) that could affect gadolinium (Gd)-contrast myocardial kinetics (in the form of accelerated contrast wash-out [a phenomenon that has been described in non-cardiac tissues 11 ] or decreased contrast extravasation, respectively), therefore compromising the ability of contrast-enhanced MRI to distinguish scar from viable myocardium 10 .…”