Development of hepatocellular carcinomas in patients with absence of tumors on a prior ultrasound examination

Joint Consensus Statement of the Indian National Association for Study of the Liver and Indian Radiological and Imaging Association for the Diagnosis and Imaging of Hepatocellular Carcinoma Incorporating Liver Imaging Reporting and Data System

Hepatocellular carcinoma (HCC) is the 6th most common cancer and the second most common cause of cancer-related mortality worldwide. There are currently no universally accepted practice guidelines for the diagnosis of HCC on imaging owing to the regional differences in epidemiology, target population, diagnostic imaging modalities, and staging and transplant eligibility. Currently available regional and national guidelines include those from the American Association for the Study of Liver Disease (AASLD), the European Association for the Study of the Liver (EASL), the Asian Pacific Association for the Study of the Liver, the Japan Society of Hepatology, the Korean Liver Cancer Study Group, Hong Kong, and the National Comprehensive Cancer Network in the United States. India with its large population and a diverse health infrastructure faces challenges unique to its population in diagnosing HCC. Recently, American Association have introduced a Liver Imaging Reporting and Data System (LIRADS, version 2017, 2018) as an attempt to standardize the acquisition, interpretation, and reporting of liver lesions on imaging and hence improve the coherence between radiologists and clinicians and provide guidance for the management of HCC. The aim of the present consensus was to find a common ground in reporting and interpreting liver lesions pertaining to HCC on imaging keeping LIRADSv2018 in mind.

Noncontrast magnetic resonance imaging versus ultrasonography for hepatocellular carcinoma surveillance (MIRACLE-HCC): study protocol for a prospective randomized trial

BACKGROUND

Biannual ultrasound (US)-with or without alpha-fetoprotein (AFP)-is recommended by current guidelines for the surveillance of hepatocellular carcinoma (HCC). However, the inadequate sensitivity of US has been a concern. Magnetic resonance imaging (MRI) is known to have high sensitivity in detecting hepatic malignancies, even without contrast enhancement. The purpose of our study is to compare US with noncontrast (unenhanced) MRI for HCC surveillance of high-risk patients.

METHODS/DESIGN

MIRACLE-HCC (usefulness of noncontrast MagnetIc Resonance imAging versus nonContrast ultrasonography for surveiLlancE of HepatoCellular Carcinoma) is a prospective, single-center, nonblinded, balanced-randomized, parallel-group study. This study was approved by our institutional review board, and informed consent will be obtained from all participating patients. All patients with compensated liver cirrhosis will undergo noncontrast US or MRI, with serum AFP testing every 6 months. If a suspicious lesion is newly detected, or if the serum AFP level is elevated in an increasing trend for two consecutive tests, dynamic contrast-enhanced imaging will be performed to confirm the diagnosis. The primary endpoints are detection rates of very early or early stage HCC, stage distribution at the initial diagnosis, and false positive referral rates, which will be compared using Fisher's exact or chi-square tests. The study will include 416 patients in a tertiary academic medical center in South Korea.

DISCUSSION

MIRACLE-HCC is the first prospective randomized trial to compare the effectiveness of noncontrast MRI and noncontrast US in the surveillance of HCC in at-risk patients. The results of this trial will show whether noncontrast MRI surveillance is superior to noncontrast US surveillance in the early detection of HCC. The trial will also determine whether there are fewer false referrals with noncontrast MRI than with noncontrast US and, eventually, whether there is improvement in the overall survival of HCC patients.

TRIAL REGISTRATION

The date of trial registration (ClincalTrials.gov: NCT02514434 ) for this study is July 23, 2015. Enrollment of participants was finished in November 2017. No authors have relationships, conditions, or circumstances that present potential conflicts of interest.

Advanced-stage hepatocellular carcinoma presenting without radiographic liver lesions

In patients with known risk factors for hepatocellular carcinoma and an elevated AFP, the diagnosis should remain on the differential even in the absence of hepatic lesions. High index of suspicion is needed, and aggressive diagnostic approaches are needed to not miss this entity.

Comparison of biannual ultrasonography and annual non-contrast liver magnetic resonance imaging as surveillance tools for hepatocellular carcinoma in patients with liver cirrhosis (MAGNUS-HCC): a study protocol

Background

Ultrasonography (US) is recommended as a standard surveillance tool for patients with a high risk of developing hepatocellular carcinoma (HCC). However, the low sensitivity of US for small HCC can lead to surveillance failure, resulting in advanced stage tumor presentations. For the early detection of HCC in high-risk patients and to improve survival and prognosis, a new efficient imaging tool with a high sensitivity for HCC detection is needed. The purpose of this study is to evaluate and compare the feasibility and efficacy of non-contrast magnetic resonance imaging (MRI) with US as a surveillance tool for HCC in patients with liver cirrhosis.

Methods

MAGNUS-HCC is a prospective, multicenter clinical trial with a crossover design for a single arm of patients. This study was approved by six Institutional Review Boards, and informed consent was obtained from all participants. All patients will undergo liver US every 6 months and non-contrast liver MRI every 12 months during a follow-up period of 3 years. If a focal liver lesion suspected of harboring HCC is detected, dynamic liver computed tomography (CT) will be performed to confirm the diagnosis. After the last surveillance round, patients without suspicion of HCC or who are not diagnosed with HCC will be evaluated with a dynamic liver CT to exclude false-negative findings. The primary endpoint is to compare the rate of detection of HCC by US examinations performed at 6-month intervals with that of yearly non-contrast liver MRI studies during a 3-year follow-up. The secondary endpoint is the survival of the patients who developed HCC within the 3-year follow-up period.

Discussion

MAGNUS-HCC is the first study to compare the feasibility of non-contrast MRI with US as a surveillance tool for the detection of HCC in high-risk patients. We anticipate that the evidence presented in this study will establish the efficacy of non-contrast MRI as a surveillance tool for HCC in high-risk patients.

Trial registration

The date of trial registration (NCT02551250) in this study was September 15, 2015, and follow-up is still ongoing.

MRI of hepatocellular carcinoma: an update of current practices

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and liver transplantation is the optimal treatment for selected patients with HCC and chronic liver disease (CLD). Accurate selection of patients for transplantation is essential to maximize patient outcomes and ensure optimized allocation of donor organs. Magnetic resonance imaging (MRI) is a powerful tool for the detection, characterization, and staging of HCC. In patients with CLD, the MRI findings of an arterial-enhancing mass with subsequent washout and enhancing capsule on delayed interstitial phase images are diagnostic for HCC. Major organizations with oversight for organ donor distribution, such as The Organ Procurement and Transplantation Network (OPTN), accept an imaging diagnosis of HCC, no longer requiring tissue biopsy. In patients that are awaiting transplantation, or are not candidates for liver transplantation, localized therapies such as transarterial chemoembolization and radiofrequency ablation may be offered. MRI can be used to monitor treatment response. The purpose of this review article is to describe the role of imaging methods in the diagnosis, staging, and follow-up of HCC, with particular emphasis on established and evolving MRI techniques employing nonspecific gadolinium chelates, hepatobiliary contrast agents, and diffusion weighted imaging. We also briefly review the recently developed Liver Imaging Reporting and Data System (LI-RADS) formulating a standardized terminology and reporting structure for evaluation of lesions detected in patients with CLD.

MRI Findings and Prediction of Time to Progression of Patients with Hepatocellular Carcinoma Treated with Drug-eluting Bead Transcatheter Arterial Chemoembolization

The purpose of this study was to investigate the utility of MRI findings after drug-eluting beads (DEB) - transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma in predicting time to progression (TTP). This study included 48 patients with 60 lesions who underwent liver MRI within 3 months after DEB-TACE. MRI was assessed for arterial enhancement pattern, late washout, arterioportal shunt, signal intensity on T2-weighted image, intratumoral septa, enhancing tissue on subtraction images, and treatment response. Cox-regression analysis was performed to identify independent factors to predict TTP. TTP was calculated using the Kaplan-Meier method with the log-rank test. Per lesion, 30 achieved complete remission, 22 had a partial response, and the remaining 8 lesions displayed stable disease on MRI. Arterial enhancement pattern, washout and enhancing tissue on subtraction images from MRI were associated with viable tumor on the last follow-up computerized tomography. Arterial enhancement, washout and enhancing tissue on subtraction images were significant predictors of TTP, but only enhancing tissue on subtraction images remained a significant predictor of TTP (P=0.018) in the multivariate analysis. TTP was longer in the group without enhancing tissue on subtraction images compared to the group with enhancing tissue (601 days vs. 287 days, P<0.001). Enhancing tissue on subtraction images from MRI after DEB-TACE is predictive for longer TTP.

Magnetic resonance imaging of the cirrhotic liver: An update

Noninvasive imaging has become the standard for hepatocellular carcinoma (HCC) diagnosis in cirrhotic livers. In this review paper, we go over the basics of MR imaging in cirrhotic livers and describe the imaging appearance of a spectrum of hepatic nodules marking the progression from regenerative nodules to low- and high-grade dysplastic nodules, and ultimately to HCCs. We detail and illustrate the typical imaging appearances of different types of HCC including focal, multi-focal, massive, diffuse/infiltrative, and intra-hepatic metastases; with emphasis on the diagnostic value of MR in imaging these lesions. We also shed some light on liver imaging reporting and data system, and the role of different magnetic resonance imaging (MRI) contrast agents and future MRI techniques including the use of advanced MR pulse sequences and utilization of hepatocyte-specific MRI contrast agents, and how they might contribute to improving the diagnostic performance of MRI in early stage HCC diagnosis.

Insight into hepatocellular carcinoma biology with gadoxetate disodium-enhanced MRI

The current algorithm for the imaging diagnosis of hepatocellular carcinoma accurately detects large, progressed tumors displaying the classical imaging features of arterial hyperenhancement with 'washout' and/or 'capsule' appearance. Liver MRI with the relatively newer hepatobiliary agent, gadoxetate disodium, provides information on hepatocellular function in addition to vascularity, facilitates detection of small progressed tumors, as well as early/vaguely nodular tumors, and shows promise for characterizing hepatocellular carcinoma biology. Prediction of tumor grade, presence of biliary and stem cell markers, microvascular invasion, future hypervascularization and post-treatment recurrence have all been studied with gadoxetate disodium-enhanced MRI with encouraging results. Incorporation of gadoxetate disodium-enhanced MRI into standard diagnostic and management algorithms will likely unfold in the future.