Improved diagnosis of well-differentiated hepatocellular carcinoma with gadolinium ethoxybenzyl diethylene triamine pentaacetic acid-enhanced magnetic resonance imaging and Sonazoid contrast-enhanced ultrasonography

Development of a Novel Contrast-Enhanced Ultrasound-Based Nomogram for Superficial Lymphadenopathy Differentiation: Postvascular Phase Value

OBJECTIVE

The aim of this study was to develop and prospectively validate a prediction model for superficial lymphadenopathy differentiation using Sonazoid contrast-enhanced ultrasound (CEUS) combined with ultrasound (US) and clinical data.

METHODS

The training cohort comprised 260 retrospectively enrolled patients with 260 pathological lymph nodes imaged between January and December 2020. Two clinical US-CEUS models were created using multivariable logistic regression analysis and compared using receiver operating characteristic curve analysis: Model 1 included clinical and US characteristics; Model 2 included all confirmed predictors, including CEUS characteristics. Feature contributions were evaluated using the SHapley Additive exPlanations (SHAP) algorithm. Data from 172 patients were prospectively collected between January and May 2021 for model validation.

RESULTS

Age, tumor history, long-axis diameter of lymph node, blood flow distribution, echogenic hilus, and the mean postvascular phase intensity (MPI) were identified as independent predictors for malignant lymphadenopathy. The area under the curve (AUC), sensitivity, specificity, and accuracy of MPI alone was 0.858 (95% confidence interval [CI], 0.817-0.891), 86.47%, 74.55%, and 81.2%, respectively. Model 2 had an AUC of 0.919 (95% CI, 0.879-0.949) and good calibration in training and validation cohorts. The incorporation of MPI significantly enhanced diagnostic capability (p < 0.0001 and p = 0.002 for training and validation cohorts, respectively). Decision curve analysis indicated Model 2 as the superior diagnostic tool. SHAP analysis highlighted MPI as the most pivotal feature in the diagnostic process.

CONCLUSION

The employment of our straightforward prediction model has the potential to enhance clinical decision-making and mitigate the need for unwarranted biopsies.

Correlation between CEUS LI-RADS categorization of HCC < 20 mm and clinic-pathological features

OBJECTIVE

To retrospectively evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) LI-RADS in liver nodules < 20 mm at high risk of hepatocellular carcinoma (HCC) and their correlation with clinic-pathological features.

METHODS

A total of 432 pathologically proved liver nodules < 20 mm were included from January 2019 to June 2022. Each nodule was categorized as LI-RADS grade (LR)-1 to LR-5 through LR-M according to CEUS LI-RADS. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of CEUS LI-RADS were evaluated using pathological reference standard. Correlations between clinic-pathological features and CEUS LI-RADS categorization, together with major CEUS features, were further explored.

RESULTS

With LR-5 to diagnose HCC, the sensitivity, specificity, PPV, NPV, and AUC were 50.3%, 70.0%, 91.2%, 18.5%, and 0.601, respectively. The proportion of LR-5 in primary HCCs was significantly higher than that in recurrent ones (p = 0.014). HCC 10-19 mm showed significantly more frequent arterial phase hyper-enhancement (APHE) and late washout (p < 0.05) and less no-washout (p = 0.003) compared with those in HCC < 10 mm. Well-differentiated HCCs showed more frequent non-APHE and no-washout than moderate- and poor-differentiated HCCs (p < 0.05). Upgrading "APHE without washout" LR-4 nodules 10-19 mm with HCC history and "APHE with late mild washout" LR-4 nodules < 10 mm to LR-5 could improve the diagnostic performance of LR-5. The corresponding sensitivity, specificity, PPV, NPV, and AUC are 60.2%, 70.0%, 92.6%, 22.1%, and 0.651, respectively.

CONCLUSIONS

CEUS LI-RADS is valuable in the diagnosis of HCC < 20 mm and performance can be improved with the combination of clinic-pathological features.

CRITICAL RELEVANCE STATEMENT

CEUS LI-RADS was valuable in the diagnosis of HCC < 20 mm and its diagnostic performance can be improved by combining clinic-pathological features. Further research is needed to define its value in this set of lesions.

KEY POINTS

Contrast-enhanced ultrasound can detect small liver lesions where LI-RADS accuracy is uncertain. Many LI-RADS Grade-4 nodules were upgraded to Grade-5 by combining imaging with clinic-pathological factors. The reclassification of LI-RADS Grade-5 can improve sensitivity without decreasing positive predictive value.

Assessment of arterial-phase hyperenhancement and late-phase washout of hepatocellular carcinoma-a meta-analysis of contrast-enhanced ultrasound (CEUS) with SonoVue® and Sonazoid®

OBJECTIVES

The recognition of arterial phase hyperenhancement (APHE) and washout during the late phase is key for correct diagnosis of hepatocellular carcinoma (HCC) with contrast-enhanced ultrasound (CEUS). This meta-analysis was conducted to compare SonoVue®-enhanced and Sonazoid®-enhanced ultrasound in the assessment of HCC enhancement and diagnosis.

METHODS

Studies were included in the analysis if they reported data for HCC enhancement in the arterial phase and late phase for SonoVue® or in the arterial phase and Kupffer phase (KP) for Sonazoid®. Forty-two studies (7502 patients) with use of SonoVue® and 30 studies (2391 patients) with use of Sonazoid® were identified. In a pooled analysis, the comparison between SonoVue® and Sonazoid® CEUS was performed using chi-square test. An inverse variance weighted random-effect model was used to estimate proportion, sensitivity, and specificity along with 95% confidence interval (CI).

RESULTS

In the meta-analysis, the proportion of HCC showing APHE with SonoVue®, 93% (95% CI 91-95%), was significantly higher than the proportion of HCC showing APHE with Sonazoid®, 77% (71-83%) (p < 0.0001); similarly, the proportion of HCC showing washout at late phase/KP was significantly higher with SonoVue®, 86% (83-89%), than with Sonazoid®, 76% (70-82%) (p < 0.0001). The sensitivity and specificity for the detection of APHE plus late-phase/KP washout detection in HCC were also higher with SonoVue® than with Sonazoid® (sensitivity 80% vs 52%; specificity 80% vs 73% in studies within unselected patient populations).

CONCLUSION

APHE and late washout in HCC are more frequently observed with SonoVue® than with Sonazoid®. This may affect the diagnostic performance of CEUS in the diagnosis of HCCs.

CLINICAL RELEVANCE STATEMENT

Meta-analysis data show the presence of key enhancement features for diagnosis of hepatocellular carcinoma is different between ultrasound contrast agents, and arterial hyperenhancement and late washout are more frequently observed at contrast-enhanced ultrasound with SonoVue® than with Sonazoid®.

KEY POINTS

• Dynamic enhancement features are key for imaging-based diagnosis of HCC. • Arterial hyperenhancement and late washout are more often observed in HCCs using SonoVue®-enhanced US than with Sonazoid®. • The existing evidence for contrast-enhanced US may need to be considered being specific to the individual contrast agent.

Characterization of hepatobiliary phase hypointense nodules without arterial phase hyperenhancement on gadoxetic acid-enhanced MRI via contrast-enhanced ultrasound using perfluorobutane

PURPOSE

Hepatobiliary phase (HBP) hypointense nodules without arterial phase hyperenhancement (APHE) on gadoxetic acid-enhanced MRI (GA-MRI) may be nonmalignant cirrhosis-associated nodules or hepatocellular carcinomas (HCCs). We aimed to characterize HBP hypointense nodules without APHE on GA-MRI by performing contrast-enhanced ultrasound using perfluorobutane (PFB-CEUS).

METHODS

In this prospective, single-center study, participants at high-risk of HCC having HBP hypointense nodules without APHE at GA-MRI were enrolled. All participants underwent PFB-CEUS; if APHE and late, mild washout or washout in the Kupffer phase were present, the diagnosis of HCC was established according to the v2022 Korean guidelines. The reference standard consisted of histopathology or imaging. The sensitivity, specificity, and positive/negative predictive values of PFB-CEUS for detecting HCC were calculated. Associations between clinical/imaging features and the diagnosis of HCC were evaluated with logistic regression analyses.

RESULTS

In total, 67 participants (age, 67.0 years ± 8.4; 56 men) with 67 HBP hypointense nodules without APHE (median size, 1.5 cm [range, 1.0-3.0 cm]) were included. The prevalence of HCC was 11.9% (8/67). The sensitivity, specificity, and positive and negative predictive values of PFB-CEUS for detecting HCC were 12.5%(1/8), 96.6%(57/59), 33.3%(1/3) and 89.1%(57/64), respectively. Mild-moderate T2 hyperintensity on GA-MRI (odds ratio, 5.756; P = 0.042) and washout in the Kupffer phase on PFB-CEUS (odds ratio, 5.828; P = 0.048) were independently associated with HCC.

CONCLUSION

Among HBP hypointense nodules without APHE, PFB-CEUS was specific for detecting HCC, which had a low prevalence. Mild-moderate T2 hyperintensity on GA-MRI and washout in the Kupffer phase on PFB-CEUS may be useful to detect HCC in those nodules.

Diagnosing Hepatocellular Carcinoma Using Sonazoid Contrast-Enhanced Ultrasonography: 2023 Guidelines From the Korean Society of Radiology and the Korean Society of Abdominal Radiology

Sonazoid, a second-generation ultrasound contrast agent, was introduced for the diagnosis of hepatic nodules. To clarify the issues with Sonazoid contrast-enhanced ultrasonography for the diagnosis of hepatocellular carcinoma (HCC), the Korean Society of Radiology and Korean Society of Abdominal Radiology collaborated on the guidelines. The guidelines are de novo, evidence-based, and selected using an electronic voting system for consensus. These include imaging protocols, diagnostic criteria for HCC, diagnostic value for lesions that are inconclusive on other imaging results, differentiation from non-HCC malignancies, surveillance of HCC, and treatment response after locoregional and systemic treatment for HCC.

Performance of adding hepatobiliary phase image in magnetic resonance imaging for detection of hepatocellular carcinoma: a meta-analysis

OBJECTIVES

To determine the performance of diagnostic algorithm of adding hepatobiliary phase (HBP) images in Gd-EOB-DTPA-enhanced MRI for the detection of hepatocellular carcinoma (HCC) measuring up to 3 cm in patients with chronic liver disease.

METHODS

We searched multiple databases from inception to April 10, 2020, to identify studies on using Gd-EOB-DTPA-enhanced MRI for the diagnostic accuracy of HCC (≤ 3 cm) in patients with chronic liver disease. The diagnostic algorithm of Gd-EOB-DTPA-enhanced MRI with HBP for HCC was defined as a nodule showing hyperintensity during arterial phase and hypointensity during the portal venous, delayed, or hepatobiliary phases. For gadoxetic acid-enhanced MRI without HBP, the diagnostic criteria were a nodule showing arterial enhancement and hypointensity on the portal venous or delayed phases. The data were extracted to calculate summary estimates of sensitivity, specificity, diagnostic odds ratio, likelihood ratio, and summary receiver operating characteristic (sROC) by using a bivariate random-effects model.

RESULTS

Twenty-nine studies with 2696 HCC lesions were included. Overall Gd-EOB-DTPA-enhanced MRI with HBP had a sensitivity of 87%, specificity of 92%, and the area under the sROC curve of 95%. The summary sensitivity of Gd-EOB-DTPA-enhanced MRI with HBP was significantly higher than that without HBP (84% vs 68%, p = 0.01).

CONCLUSION

Gd-EOB-DTPA-enhanced MRI with HBP showed higher sensitivity than that without HBP and had comparable specificity for diagnosis of HCC in patients with chronic liver disease.

KEY POINTS

• Hypointensity on HBP is a major feature for diagnosis of HCC. • Extending washout appearance to the transitional or hepatobiliary phase on Gd-EOB-DTPA provides favorable sensitivity and comparable specificity for diagnosis HCC. • The summary sensitivity of gadoxetic acid-enhanced MRI with HBP was significantly higher than that without HBP (84% vs 68%, p = 0.01) for diagnosis of HCC in patients with chronic liver disease.

The diagnostic performance of gadoxetic acid disodium-enhanced magnetic resonance imaging and contrast-enhanced ultrasound in detecting hepatocellular carcinoma: A meta-analysis

The purpose of this study was to identify and compare the diagnostic performance of gadolinium-ethoxybenzyl-diethyltriethylenetriacetic acid (Gd-EOB-DTPA) enhanced magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS) in hepatocellular carcinoma (HCC).Two researchers searched PubMed, EMBASE, and Cochrane Library databases from the inception of each database to 10 February 2020, to find comparative studies of Gd-EOB-DTPA-MRI and CEUS in detection of HCC.The study included eight studies (374 patients). MRI is superior to CEUS in diagnostic sensitivity of HCC, P = .03. The diagnostic sensitivity of MRI in lesions with a diameter of less than 30 mm was significantly higher than that of CEUS, P = .04. MRI and CEUS had no significant difference in diagnostic specificity of HCC, P = .95. Summary Receiver Operating Characteristics (SROC) of MRI showed a larger than that of CEUS, but with P > .05.Gd-EOB-DTPA-MRI showed higher sensitivity than CEUS for hepatocellular carcinoma lesions, especially for lesions of less than 30 mm across.

Differentiation of Small Hepatocellular Carcinoma From Dysplastic Nodules in Cirrhotic Liver: Texture Analysis Based on MRI Improved Performance in Comparison Over Gadoxetic Acid-Enhanced MR and Diffusion-Weighted Imaging

Background: Accurate characterization of small (3 cm) hepatocellular carcinoma (sHCC) and dysplastic nodules (DNs) in cirrhotic liver is challenging. We aimed to investigate whether texture analysis (TA) based on T2-weighted images (T2WI) is superior to qualitative diagnosis using gadoxetic acid-enhanced MR imaging (Gd-EOB-MRI) and diffusion-weighted imaging (DWI) for distinguishing sHCC from DNs in cirrhosis.

Materials and methods: Sixty-eight patients with 73 liver nodules (46 HCCs, 27 DNs) pathologically confirmed by operation were included. For imaging diagnosis, three sets of images were reviewed by two experienced radiologists in consensus: a Gd-EOB-MRI set, a DWI set, and a combined set (combination of Gd-EOB-MRI and DWI). For TA, 279 texture features resulting from T2WI were extracted for each lesion. The performance of each approach was evaluated by a receiver operating characteristic analysis. The area under the receiver operating characteristic curve (A_z), sensitivity, specificity, and accuracy were determined.

Results: The performance of TA (A_z = 0.96) was significantly higher than that of imaging diagnosis using Gd-EOB-MRI set (A_z = 0.86) or DWI set (A_z = 0.80) alone in differentiation of sHCC from DNs (P = 0.008 and 0.025, respectively). The combination of Gd-EOB-MRI and DWI showed a greater sensitivity (95.6%) but reduced specificity (66.7%). The specificity of TA (92.6%) was significantly higher than that of the combined set (P < 0.001), but no significant difference was observed in sensitivity (97.8 vs. 95.6%, P = 0.559).

Conclusion: TA-based T2WI showed a better classification performance than that of qualitative diagnosis using Gd-EOB-MRI and DW imaging in differentiation of sHCCs from DNs in cirrhotic liver. TA-based MRI may become a potential imaging biomarker for the early differentiation HCCs from DNs in cirrhosis.

Combining the Arterial Phase of Contrast-Enhanced Ultrasonography, Gadoxetic Acid-Enhanced Magnetic Resonance Imaging and Diffusion-Weighted Imaging in the Diagnosis of Hepatic Nodules ≤20 mm in Patients with Cirrhosis

Contrast-enhanced ultrasonography (CEUS) and gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) were compared with respect to diagnostic efficacy in the detection of small hepatocellular carcinoma. A new diagnostic strategy that combines the arterial phase of CEUS, the hepatobiliary phase of EOB-MRI and diffusion-weighted MR imaging (DWI) is described. One hundred sixteen nodules were enrolled to validate the performance of the strategy. For lesions ≤20 mm in size, the areas under the receiver operating characteristic curves (Az) of CEUS and EOB-MRI were 0.930 (95% confidence interval [CI]: 0.867-0.969) and 0.920 (95% CI: 0.855-0.962) (p = 0.796), respectively. The Az value of the new diagnostic strategy was 0.985 (95% CI: 0.942-0.999) (vs. CEUS, p = 0.026; vs. EOB-MRI, p = 0.014). The sensitivity, specificity and diagnostic accuracy of the new strategy were 95.5% (95% CI: 88.9%-98.8%), 96.3% (95% CI: 81.0%-99.9%) and 95.7% (95% CI: 91.9%-99.4%), respectively. The new diagnostic strategy based on the arterial phase of CEUS, hepatobiliary phase of EOB-MRI and DWI represents an appealing solution for distinguishing small hepatocellular carcinomas from benign lesions, especially when the nodules present atypical enhancement patterns.

Focal Nodular Hyperplasia of the Liver: Contrast-Enhanced Ultrasonographic Features With Sonazoid

OBJECTIVES

To investigate ultrasonographic features of focal nodular hyperplasia of the liver with contrast-enhanced ultrasonography (CEUS) using Sonazoid (perflubutane; GE Healthcare, Oslo, Norway).

METHODS

Thirty-one patients with 31 focal nodular hyperplasia nodules who underwent CEUS using Sonazoid between July 2012 and February 2015 were included in this study. After the microbubble contrast agent was injected, intermittent CEUS images were obtained during the following 4 phases: arterial (10-40 seconds), portal venous (60-90 seconds), delayed (3 minutes), and Kupffer (>10 minutes). Three abdominal radiologists retrospectively reviewed the images and achieved consensus for vascular (central artery, stellate vascularity, and centrifugal enhancement) and dynamic enhancement patterns during the late arterial, portal venous, delayed, and Kupffer phases.

RESULTS

The patients included 12 men and 19 women (age range, 21-82 years; mean, 47 years). The mean diameter of the lesions ± SD was 2.2 ± 0.9 cm (range, 1.0-4.0 cm). On CEUS, 24 of 31 lesions (77.4%) showed central artery and stellate vascularity in the early arterial phase, and 25 (80.6%) showed centrifugal enhancement. Twenty-six lesions (83.9%) were hyperechoic during the late arterial phase and showed hyperenhancement or isoenhancement during the serial dynamic phases. Kupffer-phase images indicated that only 2 lesions (6.5%) were hypoechoic compared with surrounding liver parenchyma, whereas 29 (93.5%) remained either hyperechoic (2 [6.5%]) or isoechoic (27 [87.1%]).

CONCLUSIONS

Contrast-enhanced US using Sonazoid for focal nodular hyperplasia showed typical vascular patterns of central artery vascularity, stellate vascularity, and centrifugal enhancement. Most cases were either hyperenhanced or isoenhanced on serial dynamic- and Kupffer-phase imaging. Based on these results, CEUS can provide useful information for noninvasive focal nodular hyperplasia diagnoses.

Contrast agents in dynamic contrast-enhanced magnetic resonance imaging

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a noninvasive method to assess angiogenesis, which is widely used in clinical applications including diagnosis, monitoring therapy response and prognosis estimation in cancer patients. Contrast agents play a crucial role in DCE-MRI and should be carefully selected in order to improve accuracy in DCE-MRI examination. Over the past decades, there was much progress in the development of optimal contrast agents in DCE-MRI. In this review, we describe the recent research advances in this field and discuss properties of contrast agents, as well as their advantages and disadvantages. Finally, we discuss the research perspectives for improving this promising imaging method.

Imaging for the diagnosis of hepatocellular carcinoma: A systematic review and meta-analysis

Multiphasic computed tomography (CT) and magnetic resonance imaging (MRI) are both used for noninvasive diagnosis of hepatocellular carcinoma (HCC) in patients with cirrhosis. To determine if there is a relative diagnostic benefit of one over the other, we synthesized evidence regarding the relative performance of CT, extracellular contrast-enhanced MRI, and gadoxetate-enhanced MRI for diagnosis of HCC in patients with cirrhosis. We also assessed whether liver biopsy versus follow-up with the same versus alternative imaging is best for CT-indeterminate or MRI-indeterminate liver nodules in patients with cirrhosis. We searched multiple databases from inception to April 27, 2016, for studies comparing CT with extracellular contrast-enhanced MRI or gadoxetate-enhanced MRI in adults with cirrhosis and suspected HCC. Two reviewers independently selected studies and extracted data. Of 33 included studies, 19 were comprehensive, while 14 reported sensitivity only. For all tumor sizes, the 19 comprehensive comparisons showed significantly higher sensitivity (0.82 versus 0.66) and lower negative likelihood ratio (0.20 versus 0.37) for MRI over CT. The specificities of MRI versus CT (0.91 versus 0.92) and the positive likelihood ratios (8.8 versus 8.1) were not different. All three modalities performed better for HCCs ≥2 cm. Performance was poor for HCCs <1 cm. No studies examined whether adults with cirrhosis and an indeterminate nodule are best evaluated using biopsy, repeated imaging, or alternative imaging. Concerns about publication bias, inconsistent study results, increased risk of bias, and clinical factors precluded support for exclusive use of either gadoxetate-enhanced or extracellular contrast-enhanced MRI over CT.

CONCLUSION

CT, extracellular contrast-enhanced MRI, or gadoxetate-enhanced MRI could not be definitively preferred for HCC diagnosis in patients with cirrhosis; in patients with cirrhosis and an indeterminate mass, there were insufficient data comparing biopsy to repeat cross-sectional imaging or alternative imaging. (Hepatology 2018;67:401-421).

Management consensus guideline for hepatocellular carcinoma: 2016 updated by the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality in Taiwan. To help clinical physicians to manage patients with HCC, the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan produced the management consensus guideline for HCC.

METHODS

The recommendations focus on nine important issues on management of HCC, including surveillance, diagnosis, staging, surgery, local ablation, transarterial chemoembolization/transarterial radioembolization/hepatic arterial infusion chemotherapy, systemic therapy, radiotherapy, and prevention.

RESULTS

The consensus statements were discussed, debated and got consensus in each expert team. And then the statements were sent to all of the experts for further discussion and refinement. Finally, all of the experts were invited to vote for the statements, including the level of evidence and recommendation.

CONCLUSION

With the development of the management consensus guideline, HCC patients could benefit from the optimal therapeutic modality.

Superparamagnetic iron oxide-enhanced magnetic resonance imaging is useful in predicting malignant potential of vascular transformation of hypointense hypovascular nodules on gadoxetic acid-enhanced magnetic resonance imaging

AIM

To examine whether superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) can be used to assess the malignant potential of hepatic hypovascular nodules showing hypointensity during the hepatobiliary phase (HBP) on gadoxetic acid (Gd-EOB-DTPA)-enhanced MRI.

METHODS

The study included 42 patients with chronic liver disease who had small hypovascular nodules (5-15 mm) showing hypointensity during the HBP on Gd-EOB-DTPA-enhanced MRI. The SPIO-enhanced T2-weighted MRI analyzed whether the signal intensity of each nodule was high. Nodules were prospectively followed up until hypervascularization by periodic Gd-EOB-DTPA-enhanced MRI. Initial MRI findings and clinical variables were used to analyze predictive factors for hypervascularization.

RESULTS

We analyzed 77 nodules, of which 19 (25%) showed hypervascularization during the observation period. The cumulative rates for hypervascularization were 11% and 22% at 1 and 2 years, respectively. Hyperintensity was observed in 12 nodules (16%) on SPIO-enhanced T2-weighted MRI; among these, 7 (58%) showed hypervascularization, whereas 12 (18%) of the remaining 65 nodules without hyperintensity showed hypervascularization (P = 0.007). A Cox model revealed that independent predictors of hypervascularization included hyperintense nodules on SPIO-enhanced MRI (P < 0.001). The cumulative rates for hypervascularization in hyperintense nodules on SPIO-enhanced MRI were 52% at 1 year, whereas these rates were 3% for non-hyperintense nodules.

CONCLUSION

Superparamagnetic iron oxide-enhanced MRI is useful for predicting the malignant potential of vascular transformation of hypovascular nodules with hypointensity observed in the HBP on Gd-EOB-DTPA-enhanced MRI.

Contrast-Enhanced Ultrasound Using Perfluorobutane-Containing Microbubbles in the Assessment of Liver Allograft Damage: An Exploratory Prospective Study

This prospective study investigated the usefulness of contrast (perfluorobutane-containing microbubbles)-enhanced ultrasound in the non-invasive assessment of liver allograft damage. Forty-one liver recipients underwent contrast-enhanced ultrasound followed by a liver biopsy. The hepatic filling rate (time between the arrival of contrast agent in the right hepatic artery and the maximum intensity of hepatic parenchyma) and parenchymal intensity difference before and after instantaneous high-power emission in the Kupffer phase were measured. Patients with allograft damage had higher hepatic filling rates and lower parenchymal intensity differences than those without damage (42.0 ± 16.9 vs. 30.5 ± 7.7 s, p = 0.005; 6.1 ± 7.4 vs. 16.6 ± 16.1 dB, p = 0.047, respectively). In the diagnosis of liver allograft damage, hepatic filling rate and parenchymal intensity difference had sensitivities of 61.5% and 90.9% and specificities of 92.6% and 63.6% using cutoffs of >38.5 s and ≤10.3 dB, respectively. In conclusion, contrast-enhanced ultrasound may be a promising tool in the detection of liver allograft damage.

Role of contrast-enhanced ultrasonography with Sonazoid for hepatocellular carcinoma: evidence from a 10-year experience

Hepatocellular carcinoma (HCC) represents primary liver cancer. Because the development of HCC limits the prognosis as well as the quality of life of the patients, its management should be properly conducted based on an accurate diagnosis. The liver is the major target organ of ultrasound (US), which is the simple, non-invasive, and real-time imaging method available worldwide. Microbubble-based contrast agents are safe and reliable and have become popular, which has resulted in the improvement of diagnostic performances of US due to the increased detectability of the peripheral blood flow. Sonazoid (GE Healthcare, Waukesha, WI, USA), a second-generation contrast agent, shows the unique property of accumulation in the liver and spleen. Contrast-enhanced US with Sonazoid is now one of the most frequently used modalities in the practical management of liver tumors, including the detection and characterization of the nodule, evaluation of the effects of non-surgical treatment, intraoperative support, and post-treatment surveillance. This article reviews the 10-year evidence for contrast-enhanced US with Sonazoid in the practical management of HCC.

Usefulness of early vascular phase images from contrast-enhanced ultrasonography using Sonazoid for the diagnosis of hypovascular hepatocellular carcinoma

AIM

This study aimed to evaluate the usefulness of early vascular phase images produced by contrast-enhanced ultrasonography (CE-US) with Sonazoid for the diagnosis of hypovascular hepatocellular carcinoma (HCC).

METHODS

Four hundred and seventeen patients with 674 hepatic nodules were evaluated using CE-US with Sonazoid between January 2007 and March 2010. Retrospective analysis was conducted on 49 histologically confirmed nodules showing hypovascularity relative to the surrounding liver tissue in the early vascular phase and no enhancement defect in the Kupffer phase of CE-US with Sonazoid. These nodules were classified according to early vascular phase image enhancement patterns as types I (largest avascular; avascular as a whole), II (second avascular; partially avascular), III (smallest avascular; not avascular, but faintly hypovascular relative to the surrounding liver) and IV (hypovascular as a whole with vessel-like structures passing inside nodules).

RESULTS

Among the 49 nodules, types I, II, III and IV were identified in 19 (38.8%), nine (18.4%), 15 (30.6%) and six (12.2%) cases, respectively. The proportion of tumorous nodules (well-differentiated HCC and high-grade dysplastic nodules) significantly decreased with a reduction of the avascular area (68.4% in the type I, 55.6% in the type II and 33.3% in the type III nodules; P < 0.05). All nodules demonstrating the type IV enhancement pattern were non-tumorous.

CONCLUSION

Based on the size of avascular area in the early vascular phase of CE-US with Sonazoid, we can predict the malignant potential of the nodules. CE-US with Sonazoid is very useful for evaluation of hypovascular hepatic nodules.

Predictive value of quantitative contrast-enhanced ultrasound in hepatocellular carcinoma recurrence after ablation

AIM: To investigate the relationship between contrast-enhanced ultrasound (CEUS), basic fibroblast growth factor (bFGF), endothelin-1 (ET-1), and hepatocellular carcinoma (HCC) recurrence after ablation.

METHODS: A total of 51 HCC patients (38 males and 13 females) who received radiofrequency ablation in our hospital from June 2012 to July 2014 were enrolled in this study. The patients were divided into two groups: recurrence group and non-recurrence group. Routine abdominal examination was first performed in the horizontal position. Then the patients underwent CEUS and immunohistochemical staining before receiving radiofrequency ablation. All patients were followed-up every three months for one year. The results of CEUS and serum tumor marker levels were evaluated and combined together to estimate HCC recurrence and metastasis. Patients were divided into two groups: recurrence group and non-recurrence group. Quantitative parameters of CEUS and tumor expression levels of bFGF and ET-1 were compared between the two groups, respectively. Binary logistic regression analysis was used to analyze the relationship between CEUS quantitative parameters, expression levels of ET-1 and bFGF, and HCC recurrence after ablation.

RESULTS: Based on the quantitative parameters of CEUS before patients received radiofrequency ablation, the levels of tumor rise time (tRT), tumor time to peak (tTTP), tumor peak intensity (tPI) and tumor-parenchymal peak intensity (t-pPI) in the recurrence group were significantly lower than those in the non-recurrence group (16.6 ± 6.1 vs 23.2 ± 7.0, P = 0.000; 41.2 ± 10.2 vs 59.6 ± 14.2, P = 0.000; 23.8 ± 6.7 vs 31.4 ± 6.4, P = 0.000; 7.1 ± 3.4 vs 14.6 ± 7.4, P = 0.000; respectively). The expression levels of bFGF in the recurrence group were significantly higher than those in the non-recurrence group (P < 0.05). Levels of tTTP showed a significant inverse correlation with the level of bFGF in tumors (r = -0.312, P = 0.037). The Binary logistic regression analysis results revealed that the levels of tRT, tTTP, tPI and the level of bFGF were associated with HCC recurrence after radiofrequency ablation (P < 0.05).

CONCLUSION: CEUS is a noninvasive and effective method for evaluating the angiogenesis of HCC, and predicting its recurrence and prognosis.

Imaging Techniques for the Diagnosis of Hepatocellular Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

Several imaging modalities are available for diagnosis of hepatocellular carcinoma (HCC).

PURPOSE

To evaluate the test performance of imaging modalities for HCC.

DATA SOURCES

MEDLINE (1998 to December 2014), the Cochrane Library Database, Scopus, and reference lists.

STUDY SELECTION

Studies on test performance of ultrasonography, computed tomography (CT), or magnetic resonance imaging (MRI).

DATA EXTRACTION

One investigator abstracted data, and a second investigator confirmed them; 2 investigators independently assessed study quality and strength of evidence.

DATA SYNTHESIS

Few studies have evaluated imaging for HCC in surveillance settings. In nonsurveillance settings, sensitivity for detection of HCC lesions was lower for ultrasonography without contrast than for CT or MRI (pooled difference based on direct comparisons, 0.11 to 0.22), and MRI was associated with higher sensitivity than CT (pooled difference, 0.09 [95% CI, 0.07 to 12]). For evaluation of focal liver lesions, there were no clear differences in sensitivity among ultrasonography with contrast, CT, and MRI. Specificity was generally 0.85 or higher across imaging modalities, but this item was not reported in many studies. Factors associated with lower sensitivity included use of an explanted liver reference standard, and smaller or more well-differentiated HCC lesions. For MRI, sensitivity was slightly higher for hepatic-specific than nonspecific contrast agents.

LIMITATIONS

Only English-language articles were included, there was statistical heterogeneity in pooled analyses, and costs were not assessed. Most studies were conducted in Asia and had methodological limitations.

CONCLUSION

CT and MRI are associated with higher sensitivity than ultrasonography without contrast for detection of HCC; sensitivity was higher for MRI than CT. For evaluation of focal liver lesions, the sensitivities of ultrasonography with contrast, CT, and MRI for HCC are similar.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality. (

PROSPERO

CRD42014007016).

Usefulness of contrast-enhanced ultrasonography using Sonazoid for the assessment of therapeutic response to percutaneous radiofrequency ablation for hepatocellular carcinoma

AIM

Accurate assessment of the coagulated area is imperative to achieve an excellent outcome from percutaneous radiofrequency ablation (PRFA) for the treatment of hepatocellular carcinoma (HCC). We evaluated the efficacy of contrast-enhanced ultrasonography (CEUS) with the contrast-enhancing agent Sonazoid for precisely assessing the therapeutic effect of PRFA for HCC.

METHODS

We enrolled 87 consecutive patients with solitary naïve HCC of less than 3 cm in diameter. PRFA treatment was performed with a 17-G cool-tip needle, and CEUS was performed to assess the ablative margin 3 h after the procedure, when the coagulated tumor outline was easiest to discern. The treatment was repeated until an ablative margin greater than 5 mm was confirmed. After CEUS assessment of the therapeutic response, the patients were followed to investigate local tumor recurrence.

RESULTS

In 78 patients (89.7%), the outline of the coagulated tumors could be recognized by ultrasonography, and CEUS assessment of the ablative margin was successful. The remaining nine patients were assessed by computed tomography. The 5-year cumulative survival rate after the assessment of the treatment response with CEUS was 58.4%, and the 4-year cumulative total recurrence rate was 72.3%. The 5-year cumulative local tumor recurrence rate was very low (2.3%).

CONCLUSION

The assessment with CEUS at 3 h after the PRFA procedure was successful in the majority of the patients, and it yielded a very low rate of local recurrence.

The utility of gadoxetic acid-enhanced MR imaging to characterize atypical cirrhotic nodules detected on dynamic CT images

Purpose

To evaluate whether gadoxetic acid (Gd-EOB-DTPA)-enhanced MR images of tumors taken during the hepatocyte-specific phase can aid in the differentiation between hepatocellular carcinoma (HCC) and dysplastic nodules (DNs) in patients with atypical cirrhotic nodules detected on dynamic CT images.

Materials and Methods

Seventy-one patients with 112 nodules showing atypical dynamic enhancement on CT images underwent gadoxetic acid-enhanced MR imaging (MRI) studies. Using a reference standard, we determined that 33 of the nodules were DNs and that 79 were true HCCs. Tumor size, signal intensity on precontrast T1-weighted images (T1WI) and T2WI, and the pattern of dynamic enhancement on MR images taken in the hepatocyte-phase were determined.

Results

There were significant differences in tumor size, hyperintensity on T2WI, hypointensity on T1WI, typical HCC enhancement pattern on dynamic MR images, or hypointensity on hepatocyte-phase images between DNs and HCC. The sensitivity and specificity were 60.8% and 87.9% for T2WI, 38.0% and 87.9% for T1WI, 17.7% and 100% for dynamic MR imaging, 83.5% and 84.9% for hepatocyte-phase imaging, and 60.8% and 87.9% for tumor size (threshold of 1.7 cm).

Conclusion

Gd-EOB-DTPA-enhanced hepatocyte-phase imaging is recommended for patients at high risk of HCC who present with atypical lesions on dynamic CT images.

Contrast-enhanced ultrasound: Improving the preoperative staging of hepatocellular carcinoma and guiding individual treatment

AIM: To investigate the clinical role of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CE-CT) or magnetic resonance imaging to improve the preoperative staging of hepatocellular carcinoma (HCC) and guide surgical decision-making.

METHODS: Sixty-nine patients who underwent liver resection for HCC in our center were enrolled prospectively in the study. CEUS and CE-CT/MRI were performed before surgery. Intraoperative ultrasound (IOUS) was carried out after liver mobilization. Lesions depicted by each imaging modality were counted and mapped. To investigate the impact of tumor size on the study, we divided the patients into two groups, the “Smaller group”(S-group, ≤ 5 cm in diameter) and the “Larger-group” (L-group, > 5 cm in diameter). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CE-CT/MRI, CEUS, IOUS, CEUS+CE-CT/MRI and the tumor node metastasis staging of tumors were calculated and compared. Changes in the surgical strategy as a result of CEUS and IOUS were analyzed.

RESULTS: One hundred and twenty-seven nodules, comprising 94 HCCs confirmed by histopathology and 33 benign lesions confirmed by histopathology and follow-up, were identified in 69 patients. The overall diagnostic sensitivity rates of CE-CT/MRI, CEUS, IOUS and CEUS+ CE-CT/MRI were 78.7%, 89.4%, 89.4% and 89.4%, respectively. There was a significant difference between CEUS + CE-CT/MRI and CE-CT/MRI (P = 0.046). Combining CEUS with CT or MRI increased, the diagnostic specificity compared with CT/MRI, CEUS and IOUS, and this difference was statistically significant (100%, 72.7%, 97.0%, and 69.7%, P = 0.004, P = 0.002, P = 0.002, respectively). The diagnostic accuracy was significantly higher for CEUS + CT/MRI compared with CT/MRI (92.1% vs 77.2%, P = 0.001). The TNM staging of tumors based on CEUS + CE-CT/MRI approximated to the final pathological TNM staging (P = 0.977). There was a significant difference in the accuracy of TNM staging when comparing CEUS + CE-CT/MRI with CE-CT/MRI (P = 0.002). Before surgery, strategies were changed in 15.9% (11/69) of patients as a result of CEUS. Finally, only 5.7% (4/69) of surgical strategies were changed because of IOUS findings. In the S-group, CEUS revealed 12 false positive lesions, including seven false positive lesions that were diagnosed by preoperative imaging examinations and five by IOUS. In contrast, in the L-group, IUOS revealed eight new malignant lesions; six of these lesions were true HCCs that were also identified by preoperative CEUS.

CONCLUSION: CEUS combined with CT or MRI improves the accuracy of preoperative staging for hepatocellular carcinoma and may help to guide individualized treatment for patients with HCC. CEUS may better identify non-malignant lesions in patients with small tumors and discover new malignant lesions in patients with large tumors.

Surgical resection for small hepatocellular carcinoma in cirrhosis: the Eastern experience

Detection of small Hepatocarcinoma (HCC) by screening of high-risk populations is important to increase the percentage of patients suitable for curative treatment, which would lead to prolongation of the mean survival of patients with HCC. It should be remembered that small HCC is not always necessarily equivalent to early HCC as defined histologically. With recent advances in diagnostic imaging modalities, including contrast-enhanced ultrasonography and magnetic resonance imaging with liver-specific contrast enhancement, accurate differential diagnosis of early HCCs from dysplastic nodules has become possible. Because a certain proportion of small HCCs is known to show microscopic vascular invasion, surgical resection would be the treatment of first choice. To minimize potential microscopic invasion, anatomic resection and/or resection with a wide margin should be performed, while preserving liver function to the maximum extent possible. Surgical resection, however, cannot prevent multicentric occurrence of HCC, which remains a major issue precluding curative treatment of HCC.

Hepatocellular carcinoma in a North American population: does hepatobiliary MR imaging with Gd-EOB-DTPA improve sensitivity and confidence for diagnosis?

PURPOSE

To evaluate the value of hepatobiliary phase imaging for detection and characterization of hepatocellular carcinoma (HCC) in liver MRI with Gd-EOB-DTPA, in a North American population.

MATERIALS AND METHODS

One hundred MRI examinations performed with the intravenous injection of Gd-EOB-DTPA in patients with cirrhosis were reviewed retrospectively. Nodules were classified as HCC (n = 70), indeterminate (n = 33), or benign (n = 22). Five readers independently reviewed each examination with and without hepatobiliary phase images (HBP). Lesion conspicuity scores were compared between the two readings. Lesion detection, confidence scores, and receiver operating characteristic (ROC) analysis were compared.

RESULTS

Lesion detection was slightly improved for all lesion types with the inclusion of the HBP, and was substantially higher for small HCCs (96.0% versus 85.3%). Mean confidence scores for the diagnosis of HCC increased for HCCs overall and each size category (P < 0.001). Diagnostic performance improved with the addition of the HBP (aggregate AROC 87.7% versus 80.0%, P < 0.01), and sensitivity for characterization improved (90.9% versus 78.3%, P < 0.01) while specificity was unchanged.

CONCLUSION

Hepatobiliary phase imaging may improve small lesion detection (<1 cm) and characterization of lesions in general, in MRI of the cirrhotic liver with Gd-EOB-DTPA.

Differentiation of early hepatocellular carcinoma from benign hepatocellular nodules on gadoxetic acid-enhanced MRI

OBJECTIVE

To test new diagnostic criteria for the discrimination of early hepatocellular carcinoma (HCC) from benign hepatocellular nodules on gadoxetic acid-enhanced MRI (Gd-EOB-MRI).

METHODS

We retrospectively analysed 34 patients with 29 surgically diagnosed early HCCs and 31 surgically diagnosed benign hepatocellular nodules. Two radiologists reviewed Gd-EOB-MRI, including diffusion-weighted imaging (DWI), and the signal intensity at each sequence, presence of arterial enhancement and washout were recorded. We composed new diagnostic criteria based on the lesion size and MRI findings, and then the diagnostic performance was compared with that of conventional imaging criteria with logistic regression and a generalised estimating equation method.

RESULTS

A size cut-off value (≥1.5 cm diameter) and MRI findings of T(1) hypointensity, T(2) hyperintensity, DWI hyperintensity on both low and high b-value images (b=50 and 800 s mm(-2), respectively), arterial enhancement, late washout and hepatobiliary hypointensity were selected as the diagnostic criteria. When lesions were considered malignant if they satisfied three or more of the above criteria, the sensitivity was significantly higher than when making a diagnosis based on arterial enhancement and washout alone (58.6% vs 13.8%, respectively; p=0.0002), while the specificity was 100.0% for both criteria.

CONCLUSION

Our new diagnostic criteria on Gd-EOB-MRI may help to improve the discrimination of early HCC from benign hepatocellular nodules.

Usefulness of combination of imaging modalities in the diagnosis of hepatocellular carcinoma using Sonazoid®-enhanced ultrasound, gadolinium diethylene-triamine-pentaacetic acid-enhanced magnetic resonance imaging, and contrast-enhanced computed tomography

OBJECTIVE

To clarify the diagnostic ability of combining imaging methods to diagnose hepatocellular carcinoma (HCC) using Sonazoid®-enhanced ultrasound (US), gadolinium diethylene-triamine-pentaacetic acid-enhanced (Gd-EOB-DTPA) magnetic resonance imaging (MRI), and contrast-enhanced computed tomography (CECT).

METHODS

A total of 32 patients who underwent surgical resection for HCC were studied. Sonazoid-enhanced US, Gd-EOB-DTPA MRI, CECT, and intraoperative contrast-enhanced ultrasonography were done for all patients. The definitive diagnosis of HCC in those patients was based on histopathological confirmation.

RESULTS

A total of 50 histologically proven HCCs were obtained from 32 patients; their mean (± SD) age was 68.3 years ± 8.1. The mean (± SD) nodule size was 2.6 cm ± 1.9. Twenty percent were well-differentiated HCC, 64% were moderately differentiated HCC, 10% were poorly differentiated HCC, 4% were combined HCC and CCC, and 2% were HCC with severe necrosis. The overall diagnostic sensitivity of CEUS, CECT, and Gd-EOB-DTPA MRI was 72, 74, and 86%, respectively; however, there was no significant difference between the three imaging modalities in diagnosing typical HCC (p = 0.092). When combining the diagnostic ability of the different imaging modalities, the diagnostic sensitivity of Sonazoid-enhanced US and Gd-EOB-DTPA MRI was 90%, while addition of Sonazoid-enhanced US to CECT and CECT to Gd-EOB-DTPA MRI had a sensitivity of 82 and 88%, respectively. There was no significant difference between the three imaging combinations (p = 0.970).

CONCLUSION

Sonazoid-enhanced US and Gd-EOB-DTPA MRI can be confidently used in daily clinical practice for the management of HCC.

Magnetic resonance imaging of focal liver lesions: approach to imaging diagnosis

This article is a review of magnetic resonance imaging (MRI) of incidental focal liver lesions. This review provides an overview of liver MRI protocol, diffusion-weighted imaging, and contrast agents. Additionally, the most commonly encountered benign and malignant lesions are discussed with emphasis on imaging appearance and the diagnostic performance of MRI based on a review of the literature.

APASL and AASLD Consensus Guidelines on Imaging Diagnosis of Hepatocellular Carcinoma: A Review

Consensus guidelines for radiological diagnosis of hepatocellular carcinoma (HCC) have been drafted by several large international working groups. This article reviews the similarities and differences between the most recent guidelines proposed by the American Association for Study of Liver Diseases and the Asian Pacific Association for the Study of the Liver. Current evidence for the various imaging modalities for diagnosis of HCC and their relevance to the consensus guidelines are reviewed.