Sheela Agarwal

Management of Hepatocellular Adenoma: Recent Advances

Hepatocellular adenoma (HCA) is a rare benign liver cell neoplasm that occurs more frequently in young women with a history of prolonged use of oral contraceptives. Surgical resection is considered because of the risk of hemorrhage in 25% and of malignant transformation in 5% of patients with HCA. HCA is a heterogeneous disease comprising 3 subtypes with distinct molecular and complication profiles. The inflammatory or telangiectatic subtype is at increased risk for hemorrhage, the β-catenin-activated subtype is at increased risk for malignant transformation, and the hepatocyte nuclear factor-1α-inactivated or steatotic subtype is at the least risk for complications. One-third of the patients with HCA have multiple tumors on imaging with no increased risk of complications. Magnetic resonance imaging is the modality of choice for the diagnosis and subtype characterization of HCA. Systematic resection of HCA is recommended in male patients owing to the higher incidence of malignant transformation, and surgical excision in women should be reserved for tumors 5 cm or larger associated with an increased risk of complications. Cessation of hormonal therapy and radiologic surveillance in women with HCA tumors smaller than 5 cm shows that the vast majority of HCA remain stable or undergo spontaneous regression. Percutaneous core needle biopsy is of limited value because the therapeutic strategy is based primarily on patient sex and tumor size. Transarterial embolization is the initial treatment for HCA complicated by hemorrhage. Pregnancy should not be discouraged in the presence of HCA, however, frequent sonographic surveillance is recommended.

Inflammatory Hepatocellular Adenomas Can Mimic Focal Nodular Hyperplasia on Gadoxetic Acid–Enhanced MRI

OBJECTIVE Inflammatory hepatocellular adenoma (HCA) is a recently categorized entity of hepatocellular neoplasms. We investigated whether gadoxetic acid-enhanced MRI can distinguish inflammatory HCA from focal nodular hyperplasia (FNH). MATERIALS AND METHODS From January 1, 2009, through January 1, 2013, gadoxetic acid-enhanced MRI examinations from two institutions were reviewed for HCA, with specific histologic features of inflammatory HCA. Biopsy and resection slides were reviewed, and immunohistochemistry for glutamine synthetase was performed in a subset to confirm the initial diagnosis. RESULTS A total of 10 possible cases of inflammatory HCA were identified in the pathology database. On the basis of glutamine synthetase staining performed for this study, three cases were rediagnosed as FNH and thus were excluded from the study. Therefore, a total of seven patients with inflammatory HCA were identified. On gadoxetic acid-enhanced MRI, four of these patients had classic features of FNH (group A, FNH mimics), and three had imaging features suggestive of HCA (group B, typical inflammatory HCA). Imaging features that were considered diagnostic of FNH included isointense or minimal T2 hyperintensity, arterial enhancement, and diffuse hyperintensity on hepatobiliary phase. Three of the four patients with FNH mimics had slides available for pathologic rereview, and the diagnosis of inflammatory HCA was supported by glutamine synthetase immunohistochemistry findings. The pathology reports of the remaining four cases were rereviewed and were also found to have features consistent with inflammatory HCA. CONCLUSION Inflammatory HCA can mimic FNH on MRI, including hepatobiliary phase hyperintensity. Moreover, conventional pathology using histopathology alone may lead to misclassification of inflammatory HCA.

Retrospective assessment of prevalence of nephrogenic systemic fibrosis (NSF) after implementation of a new guideline for the use of gadobenate dimeglumine as a sole contrast agent for magnetic resonance examination in renally impaired patients

From May 2007 to January 2008, patients with Stage 3‐5 chronic kidney disease (CKD) undergoing gadobenate dimeglumine (GBD)‐enhanced magnetic resonance (MR) examinations were included in the retrospective investigation. The electronic medical records were reviewed to assess the prevalence of nephrogenic systemic fibrosis (NSF) in renally impaired patients underwent GBD‐enhanced MR examinations. In all, 250 patients (98 men, mean age 72.6 years) were included: 97% of the patients had Stage 3 CKD (estimated GFR 30–59 mL/min/1.73 m2); 37% had been exclusively exposed to GBD. The remaining were exposed to GBD and other gadolinium‐based contrast agents (GBCAs). The mean dose of GBD was 22 mL (standard deviation [SD], 11.2). Including exposure to other GBCAs, the mean cumulative dose of gadolinium was 61 mL (SD, 62.3). A total of 206 patients (82%) had skin examinations following the last GBD administration (mean duration, 108 days). No evidence of suspected or diagnosed NSF was found. In conclusion, on the basis of a retrospective chart review there was no skin evidence of NSF in predominantly Stage 3 CKD patients who were exposed to GBD at an average follow‐up of 108 days, either solely or in combination with other GBCAs. J. Magn. Reson. Imaging 2009;30:1335–1340.

New Liver Imaging Techniques

Over the past decade, major technological advances have occurred in all the imaging modalities that have provided a completely new perspective to hepatic imaging. Dual-energy computed tomography (CT) acquires images at two different photon energies concurrently, and permits material decomposition based on the energy-dependent attenuation profile of specific material. It provides both morphologic and functional information in the same study, and potentially benefits hepatic tumor imaging. Hardware and software improvements in magnetic resonance imaging (MRI) technology have enabled faster MRI scanning and improved image quality. In addition to several newer MRI pulse sequences, the introduction of a new hepatocyte-specific contrast agent, gadoxetate disodium, offers additional benefits for improved detection and characterization of focal lesions, and allows functional hepatic and biliary imaging. In this article, we discuss the recent advances in CT and MRI technology and their applications for improving hepatic imaging.

The Double-edged Sword of Functional Liver Imaging

Nassif et al have shown that the physiologic properties of gadolinium ethoxybenzyl dimeglumine that enable certain lesion characterization are also responsible for the variability in MR imaging features in different patients.

Retail Venue Based Screening Mammography: Assessment of Women's Preferences.

RATIONALE AND OBJECTIVES The aim of this study was to explore womens interest and preferences in undergoing screening mammography in a retail health care setting. MATERIALS AND METHODS Self-administered surveys were distributed to 400 mammography patients in May to June 2009. All of the women who were asked were eligible for screening (age >40 years, no abnormal mammographic findings in the recent past). Three hundred eighty-six screening-eligible women filled out and returned the self-administered survey. RESULTS The average respondent age was 57 years. Three hundred ten of the patients (80.3%) had college or postgraduate educations. Two hundred three (52.6%) reported annual incomes >

CT Liver Imaging: What is New?

60,000. Two hundred forty-one respondents (62.4%) had been undergoing screening mammography for >10 years, while this was the first examination for eight patients (2%). More than half of the patients (n = 215 [55.7%]) affirmed their interest in undergoing annual screening mammography in a private area within a retail shopping facility. Most preferred a pharmacy (77%) over Wal-Mart or a grocery store. Appealing factors about a retail setting were proximity to home (90%), free parking (62%), and operating hours (48.8%). CONCLUSIONS There is interest among women in undergoing screening mammography at retail health care clinics, preferably pharmacies. The provision of services at a convenient location can increase adherence to guidelines for screening mammography.

Appearance of hepatocellular adenomas on gadoxetic acid-enhanced MRI

This review article aims to bring the reader up to date on advances in liver CT imaging, with an emphasis on the literature from the past year. Recent studies and developments in hepatic imaging using dual-energy CT, perfusion CT, low-tube-voltage imaging, and iterative reconstruction techniques are discussed.