Hepatospecific MR contrast agent uptake on hepatobiliary phase can be used as a biomarker of marked ß-catenin activation in hepatocellular adenoma.

OBJECTIVES: To assess the value of hepatospecific MR contrast agent uptake on hepatobiliary phase (HBP) images to detect marked activation of the ß-catenin pathway in hepatocellular adenomas (HCAs). METHODS: This multicentric retrospective IRB-approved study included all patients with a pathologically proven HCA who underwent gadobenate dimeglumine-enhanced liver MRI with HBP. Tumor signal intensity on HBP was first assessed visually, and lesions were classified into three distinct groups-hypointense, isointense, or hyperintense-according to the relative signal intensity to liver. Uptake was then quantified using the lesion-to-liver contrast enhancement ratio (LLCER). Finally, the accuracy of HBP analysis in depicting marked ß-catenin activation in HCA was evaluated. RESULTS: A total of 124 HCAs were analyzed including 12 with marked ß-catenin activation (HCA B+). Visual analysis classified 94/124 (76%), 12/124 (10%), and 18/124 (14%) HCAs as being hypointense, isointense, and hyperintense on HBP, respectively. Of these, 1/94 (1%), 3/12 (25%), and 8/18 (44%) were HCA B+, respectively (p < 0.001). The LLCER of HCA B+ was higher than that of HCA without marked ß-catenin activation in the entire cohort (means 4.9 ± 11.8% vs. - 19.8 ± 11.4%, respectively, p < 0.001). A positive LLCER, i.e., LLCER ≥ 0%, had 75% (95% CI 43-95%) sensitivity and 97% (95% CI 92-99%) specificity, with a LR+ of 28 (95% CI 8.8-89.6) for the diagnosis of HCA B+. CONCLUSIONS: Hepatospecific contrast uptake on hepatobiliary phase is strongly associated with marked activation of the ß-catenin pathway in hepatocellular adenoma, and its use might improve hepatocellular adenoma subtyping on MRI. KEY POINTS: • Tumor uptake on hepatobiliary phase in both the visual and quantitative analyses had a specificity higher than 90% for the detection of marked ß-catenin activation in hepatocellular adenoma. • However, the sensitivity of visual analysis alone is inferior to that of LLCER quantification on HBP due to the high number of HCAs with signal hyperintensity on HBP, especially those developed on underlying liver steatosis.

Point-shear wave elastography predicts liver hypertrophy after portal vein embolization and postoperative liver failure.

PURPOSE: To correlate point-shear wave elastography (SWE) with liver hypertrophy after right portal vein embolization (RPVE) and to determine its usefulness in predicting postoperative liver failure in patients undergoing partial liver resection. PATIENTS AND METHODS: Point-SWE was performed the day before RPVE in 56 patients (41 men) with a median age of 66 years. The percentage (%) of future remnant liver (FRL) volume increase was defined as: %FRLpost-%FRLpre%FRLpre×100 and assessed on computed tomography performed 4 weeks after RPVE. RESULTS: Median (range) %FRLpre and %FRLpost was respectively, 31.5% (12-48%) and 41% (23-61%) (P<0.001), with a median %FRL volume increase of 25.6% (-8; 123%). SWE correlated with %FRL volume increase (P=-0.510; P<0.001). SWV (P=0.003) and %FRLpre (P<0.001) were associated with %FRL volume increase at multivariate regression analysis. Forty-three patients (77%) were operated. Postoperative liver failure occurred in 14 patients (32.5%). Median SWE was different between the group with (1.68m/s) and without liver failure (1.07m/s) (P=0.018). The AUROC of SWE predicting liver failure was 0.724 with a best cut-off of 1.31m/s, corresponding to a sensitivity of 21%, specificity of 96%, positive predictive value 75% and negative predictive value of 72%. SWE was the single independent preoperative variable associated with liver failure. CONCLUSIONS: SWE assessed by point-SWE is a simple and useful tool to predict the FRL volume increase and postoperative liver failure in a population of patients with liver tumor.

Steatotic hepatocellular adenomas with different phenotypic subtypes: a case report.

Hepatocellular adenomas (HCAs) are heterogeneous group of benign tumors; three pathomolecular subtypes have been identified so far: hepatocyte nuclear factor 1 α-inactivated HCA (H-HCA) (35-40%), inflammatory HCA (I-HCA) (>50%), ß-catenin activated HCA (10%). Ten percent of I-HCA are also ß-catenin activated. We report a rare case of three histologically confirmed steatotic HCAs of three different phenotypes: I-HCA, ß-catenin activated I-HCA, and H-HCA in a 36-year-old woman. This observation outlines that in the same patient, HCA may be of different subtypes. The predisposition to develop different HCA hypothetically caused by a "benign tumorigenic field effect" may result, even rarely, in different genotypes/phenotypes such as H-HCA and I-HCA. Moreover, we illustrate the very high specificity of MR for subtyping HCA.

Hepar lobatum carcinomatosum associated with liver metastases from breast cancer: report of five cases.

BACKGROUNDS AND AIMS: Hepar lobatum carcinomatosum (HLC) is an exceptional acquired hepatic distortion which consists in irregularly lobulated hepatic contours seen in patients with known liver metastases, usually from breast carcinoma. We aimed to describe and analyze five similar cases of HLC resulting from metastatic mammary carcinoma in the liver and associated with rapid hepatic failure. METHODS: Five cases of HLC were investigated. Medical (including blood liver tests), radiological and histological data (2 cases) were collected and retrospectively analyzed. All patients were followed up for metastatic invasive ductal carcinoma of the breast and had a common pattern of treatment with combination of targeted therapies (bevacizumab, AVASTIN) and chemotherapy (paclitaxel, TAXOL). RESULTS: All the patients showed rapid hepatic failure after a mean of 9 courses of bevacizumab/paclitaxel. In all cases, liver imaging revealed liver capsule retraction and an irregular lobular margin. An apparent tumor regression of all liver metastases was showed in two cases. Biopsies were consistent with sinusoidal obstruction syndrome (SOS) and, surprisingly, no tumoral cells were found. CONCLUSION: Although rare, such an unusual pattern of liver metastasis may mimick acute cirrhosis and cause rapid hepatic failure in patients, despite possible apparent tumor regression on imaging. The etiology of this pathology is unclear, and may involve multiple pathogenic factors. Direct or indirect vascular injury plays an important role in the development of HLC.

[An ophthalmologic diagnostic error leading to a rare systemic diagnosis: Erdheim-Chester disease]. / Une errance diagnostique ophtalmologique aboutissant à un diagnostic systémique rare: la maladie d'Erdheim-Chester.

INTRODUCTION: Erdheim-Chester disease is a rare systemic disease. The diagnosis is difficult due to significant clinical and morphological polymorphism. Orbital involvement is rare, but constitutes a classic means of detection. OBSERVATION: We report the case of a 60-year-old man, who consulted for evaluation of bilateral retro-orbital tumors. These tumors had been discovered on head CT two years previously during work-up of proptosis. Two biopsies were performed. The first one revealed polymorphous inflammatory tissue. The second one revealed intense granulomatous reaction, rich in non-specific foamy histiocytes. Thoracic-abdominal-pelvic CT scan detected peri-aortic and retroperitoneal infiltration. The association of these signs pointed to a diagnosis of Erdheim-Chester disease, confirmed by the re-examination of the histological samples. DISCUSSION: Erdheim-Chester disease is a rare non-Langerhans histiocytosis with a specific tropism for perivascular and fatty connective tissue. The cause is not known. The diagnosis of this systemic disease is histological. CONCLUSION: In the case of bilateral intra-orbital tumors, the diagnosis of Erdheim-Chester disease must be considered.

Pulmonary aspergilloma in a cavity formed after percutaneous radiofrequency ablation.

We report two cases of pulmonary aspergilloma (PA) in a cavity formed after percutaneous radiofrequency ablation (PRFA), a rare complication that has only been described once in the literature. The first patient was a 59-year-old white woman treated for a secondary lung nodule of an advanced hepatocellular carcinoma. One month after PRFA, a consolidation of a cavity was noticed with an "air crescent sign," and aspergilloma serology was highly positive. A bisegmentectomy was performed due to the proximity of the lesion to mediastinal vessels and the absence of significant regression after antifungal treatment. Histological examination confirmed the diagnosis of PA. The second patient was a 61-year-old white man followed-up for a non-small-cell lung cancer. A cavitation with thick margins in the ablation zone was noticed 6 months after PRFA. A biopsy was performed, and aspergilloma was diagnosed. Medical treatment with itraconazole was administered for 13 months, and there was significant regression.

Interest of contrast-enhanced sonography to identify focal nodular hyperplasia with sinusoidal dilatation.

BACKGROUND AND AIMS: Focal nodular hyperplasia with major sinusoidal dilatation (FNH-sd) is a misleading entity, with some features resembling inflammatory hepatocellular adenoma (HCA). We aimed to assess the performance of contrast-enhanced ultrasound (CEUS) for the diagnosis of FNH-sd. METHODS: Four histologically proven FNH-sd nodules in four patients were investigated with both MRI and CEUS imaging. Sinusoidal dilatation was focally visible in all cases in histology. RESULTS: In MRI, in all the four cases, lesions were hypervascular in arterial phase, with high intensity in T2-weighted sequence imaging and persistent enhancement in the delayed gadolinium-enhanced phase. These MRI features were more indicative of HCA than FNH. On the other hand, CEUS showed a very specific centrifugal filling followed by a strong, homogeneous enhancement of the whole lesion. CONCLUSION: CEUS seems to be an essential step for the diagnosis of non-typical FNH, such as FNH-sd. This small series highlights the interest of performing both CEUS and MRI for the diagnosis of atypical focal liver lesions, such as FNH-sd.

Ultrasound elastography in liver.

Conventional imaging techniques cannot provide information about tissue mechanical properties. Many injuries can cause changes in tissue stiffness, especially tumors and fibrosis. In recent years, various non-invasive ultrasound methods have been developed to study tissue elasticity for a large number of applications (breast, thyroid, prostate, kidneys, blood vessels, liver…). For non-invasive assessment of liver diseases, several ultrasound elastography techniques have been investigated: Transient elastography (the most extensively used), Real Time Elastography (RTE), Acoustic Radiation Force Impulse Imaging (ARFI) and more recently Shear Wave Elastography (SWE). Even if evaluation of liver fibrosis in chronic liver disease remains the principal application, there are many others applications for liver: predicting cirrhosis-related complications; monitoring antiviral treatments in chronic viral liver disease; characterizing liver tumors; monitoring local treatments, etc. The aim of this article is to report on the different hepatic ultrasound elastography techniques, their advantages and disadvantages, their diagnostic accuracy, their applications in clinical practice.

Volumetric feedback ablation of uterine fibroids using magnetic resonance-guided high intensity focused ultrasound therapy.

OBJECTIVE: The purpose of this prospective multicenter study was to assess the safety and technical feasibility of volumetric Magnetic Resonance-guided High Intensity Focused Ultrasound (MR-HIFU) ablation for treatment of patients with symptomatic uterine fibroids. METHODS: Thirty-three patients with 36 fibroids were treated with volumetric MR-HIFU ablation. Treatment capability and technical feasibility were assessed by comparison of the Non-Perfused Volumes (NPVs) with MR thermal dose predicted treatment volumes. Safety was determined by evaluation of complications or adverse events and unintended lesions. Secondary endpoints were pain and discomfort scores, recovery time and length of hospital stay. RESULTS: The mean NPV calculated as a percentage of the total fibroid volume was 21.7%. Correlation between the predicted treatment volumes and NPVs was found to be very strong, with a correlation coefficient r of 0.87. All patients tolerated the treatment well and were treated on an outpatient basis. No serious adverse events were reported and recovery time to normal activities was 2.3 ± 1.8 days. CONCLUSION: This prospective multicenter study proved that volumetric MR-HIFU is safe and technically feasible for the treatment of symptomatic uterine fibroids. KEY POINTS: • Magnetic-resonance-guided high intensity focused ultrasound allows non-invasive treatment of uterine fibroids. • Volumetric feedback ablation is a novel technology that allows larger treatment volumes • MR-guided ultrasound ablation of uterine fibroids appears safe using volumetric feedback.

Can elastometry be used for a better identification of cirrhosis?

Increased stiffness has been directly associated to fibrosis. Stage 4 fibrosis defines cirrhosis. Can elastometry (transient elastography, acoustic radiation force impulse imaging) be used for a better identification of cirrhosis? The answer is obviously yes, provided hepatologists, radiologists, pathologists, and biologists combine their expertise because severe chronic liver disease is a complex subject. Considering the pathogenesis of cirrhosis, it is likely that factors such as parenchymal extinction (leading to atrophy of the liver mass with approximation of portal tracts and hepatic veins) and exudation (congestion) play a role in liver stiffness not mentioning heart failure, liver necrosis and extrahepatic cholestasis. Neglecting these factors, elastometry will lead too often to a wrong appreciation of the degree and type of liver damage and eventually to wrong medical decision.