Abbreviated Magnetic Resonance Imaging for HCC Surveillance

MRI for hepatocellular carcinoma and the role of abbreviated MRI for surveillance of hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) constitutes the majority of liver cancers and significantly impacts global cancer mortality. While ultrasound (US) with or without alpha-fetoprotein is the mainstay for HCC surveillance, its limitations highlight the necessity for more effective surveillance tools. Therefore, this review explores evolving imaging modalities and abbreviated magnetic resonance imaging (MRI) (AMRI) protocols as promising alternatives, addressing challenges in HCC surveillance.

AREAS COVERED

This comprehensive review delves into the evaluation and challenges of HCC surveillance tools, focusing on non-contrast abbreviated MRI (NC-AMRI) and contrast-enhanced abbreviated MRI protocols. It covers the implementation of AMRI for HCC surveillance, patient preferences, adherence, and strategies for optimizing cost-effectiveness. Additionally, the article provides insights into prospects for HCC surveillance by summarizing meta-analyses, prospective studies, and ongoing clinical trials evaluating AMRI protocols.

EXPERT OPINION

The opinions underscore the transformative impact of AMRI on HCC surveillance, especially in overcoming US limitations. Promising results from NC-AMRI protocols indicate its potential for high-risk patient surveillance, though prospective studies in true surveillance settings are essential for validation. Future research should prioritize risk-stratified AMRI protocols and address cost-effectiveness for broader clinical implementation, alongside comparative analyses with US for optimal surveillance strategies.

Abbreviated magnetic resonance imaging in hepatocellular carcinoma surveillance: A review

Hepatocellular carcinoma (HCC) is one of the most common primary malignancies of the liver and a leading cause for cancer-related deaths worldwide. HCC surveillance aims at early detection. The recommended strategy for screening HCC is biannual ultrasound with or without alpha-fetoprotein. However, this strategy is associated with sub-optimal sensitivity. Abbreviated magnetic resonance imaging (AMRI) is a promising alternative to ultrasound (US) for surveillance of HCC. The data regarding the role of AMRI in HCC screening is evolving. There are different AMRI protocols, each having its merits and disadvantages. In this review, we discuss the need for AMRI, protocols of AMRI and hindrances to widespread adoption of AMRI.

Current Challenges and Future Direction in Surveillance for Hepatocellular Carcinoma in Patients with Nonalcoholic Fatty Liver Disease

The burden for hepatocellular carcinoma (HCC) attributed to nonalcoholic fatty liver disease (NAFLD) continues to grow in parallel with rising global trends in obesity. The risk of HCC is elevated among patients with NAFLD-related cirrhosis to a level that justifies surveillance based on cost-effectiveness argument. The quality of current evidence for HCC surveillance in all patients with chronic liver disease is poor, and even lower in those with NAFLD. For a lack of more precise risk-stratification tools, current approaches to defining a target population in noncirrhotic NAFLD are limited to noninvasive tests for liver fibrosis, as a proxy for liver-related morbidity and mortality. Beyond etiology and severity of liver disease, traditional and metabolic risk factors, such as diabetes mellitus, older age, male gender and tobacco smoking, are not enough for HCC risk stratification for surveillance efficacy and effectiveness in NAFLD. There is an association between molecular and genetic factors and HCC risk in NAFLD, and risk models integrating both clinical and genetic factors will be key to personalizing HCC risk. In this review, we discuss concerns regarding defining a target population, surveillance test accuracy, surveillance underuse, and other cost-effective considerations for HCC surveillance in individuals with NAFLD.

Surveillance Strategies for Hepatocellular Carcinoma: Recent Advances and the Shifting Paradigm

Currently, international liver societies recommend screening at-risk individuals for HCC (patients with cirrhosis regardless of etiology, and/or chronic hepatitis B virus, and/or advanced liver fibrosis) with biannual abdominal ultrasound (USG) with or without alpha-fetoprotein (AFP). The global acceptance of USG in surveillance relies on the absence of risks, non-invasiveness, and lower costs. However, the suboptimal performance of USG ± AFP in reaching direct and indirect goals of HCC surveillance highlights the need for alternative surveillance strategies. Several studies targeted contrast-enhanced magnetic resonance imaging techniques, but the main barriers for their entrance to surveillance programs have been concerns about cost-effectivity and long scan times. Overall, the HCC risk stratification appears at hand by several validated multiple score systems, but their optimal performance is obtained only in populations who show highly homogenous clinical, pathological, epidemiologic, etiologic, and therapeutic characteristics, and this limitation poses a major drawback to their sustainable use in clinical practice. We need globally validated and molecular integrated risk stratification tools to shape the future tailored HCC surveillance decision algorithms. A dynamic process for HCC surveillance algorithms awaits us owing to the expected further prospective studies focusing on risk-stratified screening strategy.

MRI is the most commonly used imaging modality for HCC screening at a tertiary care transplant center

PURPOSE

In this study, we describe the patterns of hepatocellular carcinoma (HCC) screening with imaging and factors associated with imaging modality selection in a tertiary care transplant center.

METHODS

This was a retrospective study where all adult patients with cirrhosis and/or chronic hepatitis B virus infection referred for HCC screening with ultrasound (US), CT or MRI were identified during 2017. The association between imaging methods, demographic/clinical data were analyzed by uni- and multivariate analysis.

RESULTS

A total of 1437 patients were included (median age 61y, 59% male, median BMI 27.5 kg/m², median AFP 3.4 ng/mL, 37% with HCV and 87% with cirrhosis). Index screening imaging method utilization included MRI (51%), US (33%) and CT (16%). Use of US as the index imaging modality for screening was significantly associated with race/ethnicity [Odds Ratio (OR) 1.71-2.01, all p < 0.05] in multivariate analysis. Presence of cirrhosis (OR 0.29, p < 0.001) and referral by a hepatologist (OR 0.23, p < 0.001) were associated with screening with MRI in the multivariate analysis; while gender, age, BMI, etiology and income at ZIP code of residence were not significantly associated with imaging modality selection. HCC was observed in 62 patients (prevalence 4.3%). Rate of HCC detection was significantly higher with MRI vs US (5.9% vs. 1.5%, p = 0.001).

CONCLUSION

MRI was the most frequently used modality (> 50%) for HCC screening in our tertiary care center, in contrast with the current practice guidelines. Race/ethnicity, cirrhosis and referral by a hepatologist were associated with the imaging method used for HCC screening.