New hallmark of hepatocellular carcinoma, early hepatocellular carcinoma and high-grade dysplastic nodules on Gd-EOB-DTPA MRI in patients with cirrhosis: a new diagnostic algorithm

Modified LR-5 criteria based on gadoxetic acid can improve the sensitivity in the diagnosis of hepatocellular carcinoma

BACKGROUND

Currently, only tumors classified as LR-5 are considered definitive hepatocellular carcinoma (HCC), and no further pathologic confirmation is required to initiate therapy. Previous studies have shown that the sensitivity of LR-5 is modest, and lesions enhanced by gadoxetic acid (Gd-EOB-DTPA) may exhibit lower sensitivity than those enhanced by Gd-DTPA.

AIM

To identify malignant ancillary features (AFs) that can independently and significantly predict HCC in Liver Imaging Reporting and Data System version 2018, and to develop modified LR-5 criteria to improve diagnostic performance on Gd-EOB-DTPA - enhanced magnetic resonance imaging.

METHODS

Imaging data from patients with HCC risk factors who underwent abdominal Gd-EOB-DTPA - enhanced magnetic resonance imaging were collected. Univariate and multivariate logistic regression analyses were performed to determine AFs that could independently and significantly predict HCC. The modified LR-5 criteria involved reclassifying LR-4/LR-3 lesions based on major features combined with independently significant AFs for HCC, or by substituting threshold growth with significant AFs. McNemar's test was used to compare the diagnostic performance of the modified LR-5 criteria.

RESULTS

A total of 244 lesions from 216 patients were included. Transitional phase hypointensity, mild - moderate T2 hyperintensity, and fat in mass (more than adjacent liver) were identified as significant independent predictors of HCC. Using the modified LR-5 criteria (e.g., LR-5-M1: LR-4 + transitional phase hypointensity; LR-5-M4: LR-5 by transitional phase hypointensity instead of threshold growth; LR-5-M5: LR-5 by mild - moderate T2 hyperintensity instead of threshold growth; LR-5-M8: LR-3/LR-4 + any two features of transitional phase hypointensity/mild - moderate T2 hyperintensity/fat in mass), sensitivities were significantly increased (88.5%-89.1%) compared to the standard LR-5 (60.6%; all P values < 0.05), while specificities (84.8%-89.9%) remained largely unchanged (93.7%; all P values > 0.05). The LR-5-M8 criterion achieved the highest sensitivity.

CONCLUSION

Mild - moderate T2 hyperintensity, transitional phase hypointensity, and fat in mass are independent and significant predictors of HCC malignant AFs. The modified LR-5 criteria can improve sensitivity without significantly reducing specificity.

EASL Clinical Practice Guidelines on the management of hepatocellular carcinoma

Liver cancer is the third leading cause of cancer-related deaths worldwide, with hepatocellular carcinoma (HCC) accounting for approximately 90% of primary liver cancers. Advances in diagnostic and therapeutic tools, along with improved understanding of their application, are transforming patient treatment. Integrating these innovations into clinical practice presents challenges and necessitates guidance. These clinical practice guidelines offer updated advice for managing patients with HCC and provide a comprehensive review of pertinent data. Key updates from the 2018 EASL guidelines include personalised surveillance based on individual risk assessment and the use of new tools, standardisation of liver imaging procedures and diagnostic criteria, use of minimally invasive surgery in complex cases together with updates on the integrated role of liver transplantation, transitions between surgical, locoregional, and systemic therapies, the role of radiation therapies, and the use of combination immunotherapies at various stages of disease. Above all, there is an absolute need for a multiparametric assessment of individual risks and benefits, considering the patient's perspective, by a multidisciplinary team encompassing various specialties.

Diagnostic performance of LR-5 based on hypointensity on Gd-EOB-DTPA-enhanced MRI in the hepatobiliary phase for sHCC using LI-RADS v2018 criteria

AIM

To investigate the value of the LR-5, which is based on hepatobiliary phase (HBP) hypointensity, for small hepatocellular carcinoma (sHCC) using LI-RADS v2018 criteria.

MATERIALS AND METHODS

From January 2015 to December 2021 in institution 1, and from January 2019 to February 2022 in institution 2, 239 patients at high risk for hepatocellular carcinoma (HCC) underwent contrast-enhanced MRI. Two radiologists independently evaluated the imaging features and classified them according to LI-RADS v2018 criteria, calculating the diagnostic performance of LR-5 based on consensus data. LI-RADS-m1: HBP hypointensity was used as an additional major feature along with the LI-RADS v2018. LI-RADS-m2: HBP hypointensity replaced nonperipheral "washout" in the portal venous phase. The definition of LR-DN was nodules pathologically diagnosed as high-grade dysplastic nodules (HGDN) were recategorized as LR-DN. The diagnostic performance of LR-5 was recalculated. The diagnostic performance of the LR-5 was compared using McNemar's test.

RESULTS

Using LI-RADS v2018, LI-RADS-m1, and LI-RADS-m2 criteria for LR-5, the sensitivities were 82.67%, 86.22%, and 88.44%, the specificities were 82.00%, 66.00%, and 54.00%, and the accuracies were 82.55%, 82.55%, and 82.18%, respectively. After the addition of the LR-DN, the sensitivities of LR-5 in the above diagnostic model remained unchanged, with accuracies of 84.36%, 87.27%, and 88.36% and specificities of 92.00%, 92.00%, and 88.00%, respectively.

CONCLUSIONS

HBP hypointensity may improve the sensitivity of LR-5. We attempted to propose the LR-DN, HBP hypointensity may be used as a complement to washout as an additional major feature without significantly decreasing specificity.

Hepatocellular Carcinoma: Imaging Advances in 2024 with a Focus on Magnetic Resonance Imaging

The EASL diagnostic algorithm for hepatocellular carcinoma, currently in use, dates back to 2018. While awaiting its update, numerous advancements have emerged in the field of hepatocellular carcinoma imaging. These innovations impact every step of the diagnostic algorithm, from surveillance protocols to diagnostic processes, encompassing aspects preceding a patient's inclusion in surveillance programs as well as the potential applications of imaging after the hepatocellular carcinoma diagnosis. Notably, these diagnostic advancements are particularly evident in the domain of magnetic resonance imaging. For example, the sensitivity of ultrasound in diagnosing very early-stage and early-stage hepatocellular carcinoma during the surveillance phase is very low (less than 50%) and a potential improvement in this sensitivity value could be achieved by using abbreviated protocols in magnetic resonance imaging. The aim of this review is to explore the 2024 updates in magnetic resonance imaging for hepatocellular carcinoma, with a focus on its role in surveillance, nodular size assessment, post-diagnosis imaging applications, and its potential role before the initiation of surveillance.

Advanced Imaging of Hepatocellular Carcinoma: A Review of Current and Novel Techniques

Hepatocellular carcinoma (HCC) is the most common primary carcinoma arising from the liver. Although HCC can arise de novo, the vast majority of cases develop in the setting of chronic liver disease. Hepatocarcinogenesis follows a well-studied process during which chronic inflammation and cellular damage precipitate cellular and genetic aberrations, with subsequent propagation of precancerous and cancerous lesions. Surveillance of individuals at high risk of HCC, early diagnosis, and individualized treatment are keys to reducing the mortality associated with this disease. Radiological imaging plays a critical role in the diagnosis and management of these patients. HCC is a unique cancer in that it can be diagnosed with confidence by imaging that meets all radiologic criteria, obviating the risks associated with tissue sampling. This article discusses conventional and emerging imaging techniques for the evaluation of HCC.

New strategy of LI-RADS v2018 to improve the sensitivity for small hepatocellular carcinoma ≤ 3.0 cm on extracellular-contrast enhanced MRI

INTRODUCTION

We aimed to modify LI-RADS version 2018 to improve sensitivity and determine the value of the combination of high alpha-fetoprotein (AFP) levels for small HCC (sHCC, ≤ 30 mm) diagnosis.

METHODS

A total of 984 patients at high risk for HCC, with 1204 observations (including 997 small observations ≤ 30 mm), who underwent extracellular contrast-enhanced MRI were enrolled from five independent centers. Blinded readers evaluated the LI-RADS features and categorized each observation according to the LI-RADS v2018, modified LI-RADS and EASL. Odds ratios of LI-RADS major features (MFs) and several high AFP levels for sHCC diagnosis were analyzed using multivariable logistic regression. The modified LR-5 criteria was developed by including no APHE at any size with two MFs, and non-rim APHE with one MF (≥ 10 mm) or with two MFs (< 10 mm). The diagnostic performance of each version of the LR-5 was compared using generalized estimating equations.

RESULTS

APHE, washout, enhancing capsule and five high AFP levels were independently associated with sHCC. In three datasets, the modified LI-RADS had higher sensitivities for sHCC (76.8 ∼ 85.5 % vs. 73.7 ∼ 75.9 %, P < 0.05) to the LR-5 v2018. The modified LI-RADS with AFP ≥ 200 ng/mL as an additional feature or as an alternative to threshold growth provided higher sensitivities for sHCC than LI-RADS v2018 (82.1 ∼ 90.1 % vs. 73.7 ∼ 75.9 %, all P < 0.05), modified LI-RADS (82.1 ∼ 90.1 % vs. 76.8 ∼ 85.5 %, all P < 0.05) and EASL version 2018 (82.1 ∼ 90.1 % vs. 73.3 ∼ 74.7 %, all P < 0.05), with comparable specificities (all P > 0.05).

CONCLUSION

The new strategy of LI-RADS v2018 provides significantly higher sensitivity and comparable specificity than those of LI-RADS v2018 for sHCC diagnosis on ECA-MRI.

Performance of LI-RADS category 5 vs combined categories 4 and 5: a systemic review and meta-analysis

OBJECTIVE

Computed tomography (CT)/magnetic resonance imaging (MRI) Liver Imaging Reporting and Data System (LI-RADS, LR) category 5 has high specificity and modest sensitivity for diagnosis of hepatocellular carcinoma (HCC). The purpose of this study was to compare the diagnostic performance of LR-5 vs combined LR-4 and LR-5 (LR-4/5) for HCC diagnosis.

METHODS

MEDLINE and EMBASE databases through January 03, 2023 were searched for studies reporting the performance of LR-5 and combined LR-4/5 for HCC diagnosis, using CT/MRI LI-RADS version 2014, 2017, or 2018. A bivariate random-effects model was used to calculate the pooled per-observation diagnostic performance. Subgroup analysis was performed based on imaging modalities and type of MRI contrast material.

RESULTS

Sixty-nine studies (15,108 observations, 9928 (65.7%) HCCs) were included. Compared to LR-5, combined LR-4/5 showed significantly higher pooled sensitivity (83.0% (95% CI [80.3-85.8%]) vs 65.7% (95% CI [62.4-69.1%]); p < 0.001), lower pooled specificity (75.0% (95% CI [70.5-79.6%]) vs 91.7% (95% CI [90.2-93.1%]); p < 0.001), lower pooled positive likelihood ratio (3.60 (95% CI [3.06-4.23]) vs 6.18 (95% CI [5.35-7.14]); p < 0.001), and lower pooled negative likelihood ratio (0.22 (95% CI [0.19-0.25]) vs 0.38 (95% CI [0.35-0.41]) vs; p < 0.001). Similar results were seen in all subgroups.

CONCLUSIONS

Our meta-analysis showed that combining LR-4 and LR-5 would increase sensitivity but decrease specificity, positive likelihood ratio, and negative likelihood ratio. These findings may inform management guidelines and individualized management.

CLINICAL RELEVANCE STATEMENT

This meta-analysis estimated the magnitude of changes in the sensitivity and specificity of imaging criteria when LI-RADS categories 4 and 5 were combined; these findings can inform management guidelines and individualized management.

KEY POINTS

There is no single worldwide reporting system for liver imaging, partly due to regional needs. Combining LI-RADS categories 4 and 5 increased sensitivity and decreased specificity and positive and negative likelihood ratios. Changes in the sensitivity and specificity of imaging criteria can inform management guidelines and individualized management.

An overview of risk assessment and monitoring of malignant transformation in cirrhotic nodules

Cirrhotic liver nodules can progress to hepatocellular carcinoma (HCC) through a multi-step carcinogenesis model, with dysplastic nodules being particularly high risk. Currently, monitoring the progression of non-HCC cirrhotic nodules is primarily through dynamic observation, but there is a lack of sensitive, efficient, and convenient methods. Dynamic monitoring and risk evaluation of malignant transformation are essential for timely treatment and improved patient survival rates. Routine liver biopsies are impractical for monitoring, and imaging techniques like ultrasound, computed tomography, and magnetic resonance imaging are not suitable for all patients or for accurately assessing subcentimeter nodules. Identifying serum biomarkers with high sensitivity, specificity, and stability, and developing a multi-index evaluation model, may provide a more convenient and efficient approach to monitoring pathological changes in cirrhotic nodules.

Management Consensus Guidelines for Hepatocellular Carcinoma: 2023 Update on Surveillance, Diagnosis, Systemic Treatment, and Posttreatment Monitoring by the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related mortality in Taiwan. The Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan established HCC management consensus guidelines in 2016 and updated them in 2023. Current recommendations focus on addressing critical issues in HCC management, including surveillance, diagnosis, systemic treatment, and posttreatment monitoring. For surveillance and diagnosis, we updated the guidelines to include the role of protein induced by vitamin K absence or antagonist II (PIVKA-II) and gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) in detecting HCCs. For systemic treatment, the updated guidelines summarize the multiple choices available for targeted therapy, immune checkpoint inhibitors, and a combination of both, especially for those carcinomas refractory to or unsuitable for transarterial chemoembolization. We have added a new section, posttreatment monitoring, that describes the important roles of PIVKA-II and EOB-MRI after HCC therapy, including surgery, locoregional therapy, and systemic treatment. Through this update of the management consensus guidelines, patients with HCC may benefit from optimal diagnosis, therapeutic modalities, and posttreatment monitoring.

Trapped in Endosome PEGylated Ultra-Small Iron Oxide Nanoparticles Enable Extraordinarily High MR Imaging Contrast for Hepatocellular Carcinomas

The early diagnosis of hepatocellular carcinomas (HCCs) remains challenging in the clinic. Primovist-enhanced magnetic resonance imaging (MRI) aids HCC diagnosis but loses sensitivity for tumors <2 cm. Therefore, developing advanced MRI contrast agents is imperative for improving the diagnostic accuracy of HCCs in very-early-stage. To address this challenge, PEGylated ultra-small iron oxide nanoparticles (PUSIONPs) are synthesized and employed as liver-specific T1 MRI contrast agents. Intravenous delivery produces simultaneous hyperintense HCC and hypointense hepatic parenchyma signals on T1 imaging, creating an extraordinarily high tumor-to-liver contrast. Systematic studies uncover PUSIONP distribution in hepatic parenchyma, HCC lesions at the organ, tissue, cellular, and subcellular levels, revealing endosomal confinement of PUSIONP without aggregation. By mimicking such situations, the dependency of relaxometric properties on local PUSIONP concentration is investigated, emphasizing the key role of different endosomal concentrations in liver and tumor cells for high tumor-to-liver contrast and clear tumor boundaries. These findings offer exceptional imaging capabilities for early HCC diagnosis, potentially benefiting real HCC patients.

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.

Multiparametric MRI for characterization of the tumour microenvironment

Our understanding of tumour biology has evolved over the past decades and cancer is now viewed as a complex ecosystem with interactions between various cellular and non-cellular components within the tumour microenvironment (TME) at multiple scales. However, morphological imaging remains the mainstay of tumour staging and assessment of response to therapy, and the characterization of the TME with non-invasive imaging has not yet entered routine clinical practice. By combining multiple MRI sequences, each providing different but complementary information about the TME, multiparametric MRI (mpMRI) enables non-invasive assessment of molecular and cellular features within the TME, including their spatial and temporal heterogeneity. With an increasing number of advanced MRI techniques bridging the gap between preclinical and clinical applications, mpMRI could ultimately guide the selection of treatment approaches, precisely tailored to each individual patient, tumour and therapeutic modality. In this Review, we describe the evolving role of mpMRI in the non-invasive characterization of the TME, outline its applications for cancer detection, staging and assessment of response to therapy, and discuss considerations and challenges for its use in future medical applications, including personalized integrated diagnostics.

Decreasing Albumin mRNA Expression in Cholangiocarcinomas along the Bile Duct Tree

INTRODUCTION

The progressive technologies in albumin in situ hybridization (ISH) changed the routine application and the differential diagnosis of hepatic malignancies in the last years. The aim of the present work was to assess the diagnostic utility of albumin ISH on different cholangiocarcinoma (CCA) subtypes, as well as to assess how albumin production changes along the biliary tree.

METHODS

Forty-five CCAs were retrospectively selected: 29 intrahepatic (15 small-duct and 14 large-duct subtypes), 7 perihilar, and 9 extrahepatic. Histology was revised in all cases, and albumin ISH was automatically performed by the RNAscope®.

RESULTS

ISH was always negative in extrahepatic CCAs, only 1 perihilar case was positive, and any positivity was observed in 25/29 (86.2%) intrahepatic CCAs (p < 0.001). Concerning CCA subtypes, mean cell positivity was 38.8 ± 29.8% in small-duct CCAs and 11.4 ± 21.9 in large-duct CCAs, respectively (p = 0.003); 12/15 (80.0%) small-duct and 3/14 (21.4%) large-duct CCAs showed >5% positive cells (p = 0.002; odds ratio 14.7).

CONCLUSIONS

The introduction of more sensitive techniques changed the indications for ISH since most small-duct intrahepatic CCAs show diffuse positivity. Albumin positivity decreases from liver periphery to the large ducts, suggesting that ISH can be helpful in the differential diagnosis between small-duct and large-duct CCAs, as well as between intrahepatic large-duct CCAs and metastases.

Radiomics-based distinction of small (≤2 cm) hepatocellular carcinoma and precancerous lesions based on unenhanced MRI

AIM

To assess the feasibility of a radiomics model based on unenhanced magnetic resonance imaging (MRI) to differentiate small hepatocellular carcinoma (S-HCC) (≤2 cm) and pre-hepatocellular carcinoma (Pre-HCC).

MATERIALS AND METHODS

One hundred and fourteen histopathologically confirmed 114 hepatic nodules were analysed retrospectively. All patients had undergone MRI before surgery using a 3 T MRI system. Each nodule was segmented on unenhanced MRI sequences (T1-weighted imaging [T1] and T2WI with fat-suppression [FS-T2]). Radiomics features were extracted and the optimal features were selected using the least absolute shrinkage and selection operator (LASSO). The support vector machine (SVM) was used to establish the radiomics model. One abdominal radiologist performed the conventional qualitative analysis for classification of S-HCC and Pre-HCC. The diagnostic performances of the radiomics and radiologist models were evaluated using receiver operating characteristic (ROC) analysis.

RESULT

Radiomics features (n=1,223) were extracted from each sequence and the optimal features were selected from T1, FS-T2, and T1+FS-T2 to construct the radiomics models. The radiomics model based on T1+FS-T2 showed the best performance among the three models, with areas under the ROC curves (AUCs) of 0.95 (95 % confidence interval [CI], 0.875-0.986) and 0.942 (95 % CI, 0.775-0.985), accuracies of 86 % and 88.5 %, sensitivities of 94.12 % and 100 %, and specificities of 85.48 % and 85.19 %, respectively. The radiomics model on FS-T2 showed better performance on a single sequence than that of the T1-based model. The diagnostic performance for the radiomic model was significantly higher than that for the radiologist (AUC = 0.518, p<0.05).

CONCLUSION

This study suggested that a radiomics model based on unenhanced MRI may serve as a feasible and non-invasive tool to classify S-HCC and Pre-HCC.

Mean ADC values and arterial phase hyperintensity discriminate small (≤ 3 cm) well-differentiated hepatocellular carcinoma from dysplastic nodule

BACKGROUND/AIM

This research endeavor sought to distinguish small (≤ 3 cm) well-differentiated hepatocellular carcinoma (WD-HCC) from dysplastic nodules (DN) by employing traditional imaging features and mean apparent diffusion coefficient (mADC) values derived from diffusion-weighted imaging (DWI).

MATERIALS AND METHODS

In this retrospective analysis, we assessed a cohort of ninety patients with confirmed dysplastic nodules (DNs) (n = 71) or well-differentiated hepatocellular carcinoma (WD-HCC) (n = 41) who had undergone dynamic contrast-enhanced magnetic resonance imaging between March 2018 and June 2021. Multivariable logistic regression analyses were executed to pinpoint characteristics that can effectively differentiate histologic grades. A region-of-interest (ROI) encompassing all lesion voxels was delineated on each slice containing the mass in the ADC map. Subsequently, the whole-lesion mean ADC (mADC) were computed from these delineations. A receiver operating characteristic (ROC) curve was generated to assess the discriminatory efficacy of the mADC values in distinguishing between WD-HCC and DN.

RESULTS

Among the histopathological types from benign to malignant, mADC showed a significant decrease (P < 0.001). The mADCs were effective in distinguishing WD-HCC from DN [AUC, 0.903 (95% CI 0.849-0.958)]. The best cutoffs for the Youden index were 0.0012 mm2/s for mADC, with moderate sensitivity (70.7%) and high specificity (94.4%). MRI features including hyperintensity at arterial phase (odds ratio, 21.2; P = 0.009), mADC < 0.0012 mm2/s (odds ratio, 52.2; P < 0.001) were independent predictors for WD-HCC at multivariable analysis. The AUC value of hyperintensity at arterial phase was 0.857 (95% CI 0.786-0.928). The composite diagnostic criterion of arterial hyperintensity + mADC < 0.0012 mm2/s showed good performance [AUC, 0.926 (95% CI 0.878-0.975)], displaying increased sensitivity compared to individual assessments involving arterial hyperintensity (P = 0.013), mADC < 0.0012 mm2/s (P = 0.004), or LR-5 (P < 0.001), with similar specificity compared to LR-5 (P = 0.193).

CONCLUSION

DN and WD-HCC displayed contrasting diffusion characteristics, attainable to distinguish with satisfactory accuracy. The utilization of arterial phase hyperintensity and mADC < 0.0012 on MRI facilitated the differentiation of WD-HCC from DN.

Liver Lesions at Risk of Transformation into Hepatocellular Carcinoma in Cirrhotic Patients: Hepatobiliary Phase Hypointense Nodules without Arterial Phase Hyperenhancement

Recent technical advances in liver imaging and surveillance for patients at high risk for developing hepatocellular carcinoma (HCC) have led to an increase in the detection of borderline hepatic nodules in the gray area of multistep carcinogenesis, particularly in those that are hypointense at the hepatobiliary phase (HBP) and do not show arterial phase hyperenhancement. Given their potential to transform and advance into hypervascular HCC, these nodules have progressively attracted the interest of the scientific community. To date, however, no shared guidelines have been established for the decision management of these borderline hepatic nodules. It is therefore extremely important to identify features that indicate the malignant potential of these nodules and the likelihood of vascularization. In fact, a more complete knowledge of their history and evolution would allow outlining shared guidelines for their clinical-surgical management, to implement early treatment programs and decide between a preventive curative treatment or a watchful follow-up. This review aims to summarize the current knowledge on hepatic borderline nodules, particularly focusing on those imaging features which are hypothetically correlated with their malignant evolution, and to discuss current guidelines and ongoing management in clinical practice.

Suboptimal performance of LI-RADS v2018 on gadoxetic acid-enhanced MRI for detecting hepatocellular carcinoma in liver transplant candidates

OBJECTIVES

To evaluate the diagnostic performance for hepatocellular carcinoma (HCC) detection of the Liver Imaging Reporting and Data System (LI-RADS) version 2018 on gadoxetic acid-enhanced MRI, comparing liver transplant candidates (LT group) with patients who underwent surgical resection (SR group), and to determine significant clinical factors for diagnostic performance of LI-RADS v2018.

METHODS

Patients who underwent gadoxetic acid-enhanced MRI and subsequent SR or LT for HCC were retrospectively included between January 2019 and December 2020. The sensitivity and specificity of LI-RADS LR-5 for HCC were compared between the two groups using generalized estimating equations. The accuracy of patient allocation according to the Milan criteria was calculated for the LT group. Univariable and multivariable logistic regression analyses were performed to determine significant clinical factors associated with the sensitivity of LI-RADS.

RESULTS

Of the 281 patients, 237 were assigned to the SR group, and 44 were assigned to the LT group. The LT group showed significantly lower per-patient (48.5% vs. 79.6%, p < .001) and per-lesion sensitivity (31.0% vs. 75.9%, p < .001) than the SR group, whereas no significant difference in both per-patient (100.0% vs. 91.7%, p > .99) and per-lesion specificities (100.0% vs. 94.1%, p > .99). The accuracy of patient allocation was 50.0%. Sensitivity was significantly lower in patients with a smaller lesion size (p < .001), a larger lesion number (p = .002), and a higher Child-Pugh score (p = .009).

CONCLUSION

LI-RADS v2018 on gadoxetic acid-enhanced MRI might be insufficient in liver transplant candidates and other diagnostic imaging tests should be considered in patients with these significant clinical factors.

CLINICAL RELEVANCE STATEMENT

In liver transplant candidates with a smaller lesion size, a larger lesion number, and a higher Child-Pugh score, imaging tests other than gadoxetic acid-enhanced MRI may be clinically useful to determine the transplant eligibility.

KEY POINTS

• The sensitivity of the Liver Imaging Reporting and Data System (LI-RADS) was lower in liver transplant candidates than in those who underwent surgical resection. • With the use of gadoxetic acid-enhanced MRI, the accuracy of patient allocation for liver transplantation on the basis of the Milan criteria was suboptimal. • The sensitivity of LI-RADS v2018 was significantly associated with lesion size, lesion number, and Child-Pugh classification.

Hepatobiliary-Phase Hypointense Nodules Without Arterial-Phase Hyperenhancement: Developing a Risk Stratification for Hypervascular Transformation Based on a Real-World Observational Cohort Study

PURPOSE

To develop a risk stratification based on MRI features to predict hypervascular transformation for hepatobiliary-phase (HBP) hypointense nodules without arterial-phase hyperenhancement (APHE).

MATERIALS AND METHODS

This retrospective observational cohort study included 55 HBP hypointense nodules without APHE in 35 patients with chronic liver disease, cirrhosis, or current hepatocellular carcinoma (HCC) who underwent gadoxetic acid-enhanced MRI. The hypervascular transformation during the follow-up MRI(s) was the primary endpoint analyzed for the nodules. Univariable and multivariable Cox proportional hazard regression analyses were performed to identify risk features predicting transformation and assess their predictive value.

RESULTS

Among the 55 nodules, 27 developed hypervascular transformation, while 28 did not. Diffusion-weighted imaging (DWI) hyperintensity (hazard ratio [HR], 4.98; 95% confidence interval [CI]: 1.60, 15.54; p = 0.006) and portal venous phase (PVP) hypointensity (HR, 4.08; 95% CI: 1.43, 11.64; p = 0.009) were associated with hypervascular transformation. DWI hyperintensity and PVP hypointensity had 44.4% (95% CI: 26.0%, 64.4%) and 81.9% (95% CI: 61.3%, 93.0%) sensitivity, while their specificity was 78.2% (95% CI: 64.6%, 87.8%) and 67.9 (95% CI: 47.6%, 83.4%), respectively. The specificity of the combination of two features was 100% (95% CI: 85.0%, 100%). The hypervascular transformation rates for nodules with both, either and neither of the risk MRI findings were 100% (10/10), 60.9% (14/23), and 13.6% (3/22), respectively; the median intervals for transformation were 312 (range: 73-838), 409 (range: 50-1643) and 555 (range: 423-968) days, respectively.

CONCLUSION

The combination of DWI hyperintensity and PVP hypointensity may be used as a high-risk indicator for the hypervascular transformation of HBP hypointense nodules without APHE; nodules without either feature may be treated as low-risk nodules and could adopt an extended interval follow-up schedule.

CT and MR imaging of primary biliary cholangitis: a pictorial review

Primary biliary cholangitis (PBC) is a rare chronic autoimmune-mediated cholestatic liver disease involving medium and small bile ducts that can lead to liver fibrosis and cirrhosis. To date, the pathogenesis of PBC remains elusive, and there is currently no curative medical treatment. Computed tomography (CT) and magnetic resonance (MR) imaging, as common technical tools that allow non-invasive monitoring of liver tissue in vivo, play crucial roles in the diagnosis, staging, and prognosis prediction in PBC by enabling assessment of abnormalities in liver morphology and parenchyma, irregular configuration of bile ducts, lymphadenopathy, portal hypertension, and complications of cirrhosis. Moreover, CT and MRI can be used to monitor the disease progression after treatment of PBC (e.g. the onset of cirrhotic decompensation or HCC) to guide the clinical decisions for liver transplantation. With the optimization of imaging technology, magnetic resonance elastography (MRE) offers additional information on liver stiffness, allows for the identification of early cirrhosis in PBC and provides a basis for predicting prognosis. Gadoxetic acid-enhanced MRI enables the assessment of liver function in patients with PBC. The purpose of this review is to detail and illustrate the definition, pathological basis, and clinical importance of CT and MRI features of PBC to help radiologists and clinicians enhance their understanding of PBC.Critical Relevance StatementCharacteristic CT and MR imaging manifestations of primary biliary cholangitis may reflect the course of the disease and provide information associated with histological grading and altered cellular function.Key points• Imaging has become highly useful for differentiating PBC from other diseases.• Key pathological alterations of PBC can be captured by CT and MRI.• Characteristic manifestations provide information associated with histological grade and cellular function.• Despite this, the CT or MRI features of PBC are not specific.

Guidelines for the Diagnosis and Treatment of Primary Liver Cancer (2022 Edition)

Background

Primary liver cancer, of which around 75-85% is hepatocellular carcinoma in China, is the fourth most common malignancy and the second leading cause of tumor-related death, thereby posing a significant threat to the life and health of the Chinese people.

Summary

Since the publication of Guidelines for Diagnosis and Treatment of Primary Liver Cancer in China in June 2017, which were updated by the National Health Commission in December 2019, additional high-quality evidence has emerged from researchers worldwide regarding the diagnosis, staging, and treatment of liver cancer, that requires the guidelines to be updated again. The new edition (2022 Edition) was written by more than 100 experts in the field of liver cancer in China, which not only reflects the real-world situation in China but also may reshape the nationwide diagnosis and treatment of liver cancer.

Key Messages

The new guideline aims to encourage the implementation of evidence-based practice and improve the national average 5-year survival rate for patients with liver cancer, as proposed in the "Health China 2030 Blueprint."

Multidisciplinary consensus recommendations for management of hepatocellular carcinoma in Middle East and North Africa region

Hepatocellular carcinoma (HCC) is a growing health concern projected to cross over a million cases worldwide by 2025. HCC presents a significant burden of disease in Middle East and North African (MENA) countries due to a high prevalence of risk factors such as hepatitis C and B infections and rising incidence of non-alcoholic steatohepatitis and non-alcoholic fatty liver disease. In August 2022, an advisory meeting consisting of experts from 5 MENA countries was convened in an attempt to provide consensus recommendations on HCC screening, early diagnosis, current treatment modalities and unmet medical needs in the region. Data were collected from a pre-meeting survey questionnaire and responses analysed and presented during the advisory meeting. This review summarizes the evidence discussed at the meeting and provides expert recommendations on the management of HCC. The 2022 update of Barcelona clinic liver cancer (BCLC) staging and treatment strategy and its implementation in the MENA region was extensively discussed. A key consensus of the expert panel was that multidisciplinary care is crucial to effective patient management that results in better clinical outcomes and overall survival of the patient. The panel recommended the use of predictive and early response biomarkers to guide clinicians in arriving at more effective therapeutic decisions. The experts also emphasized the role of robust screening/surveillance systems, population-based registries, effective referral pathways and standardization of guidelines to ensure the successful management of HCC in the region.

Advances in Histological and Molecular Classification of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a primary liver cancer characterized by hepatocellular differentiation. HCC is molecularly heterogeneous with a wide spectrum of histopathology. The prognosis of patients with HCC is generally poor, especially in those with advanced stages. HCC remains a diagnostic challenge for pathologists because of its morphological and phenotypic diversity. However, recent advances have enhanced our understanding of the molecular genetics and histological subtypes of HCC. Accurate diagnosis of HCC is important for patient management and prognosis. This review provides an update on HCC pathology, focusing on molecular genetics, histological subtypes, and diagnostic approaches.

LI-RADS version 2018 for hepatocellular carcinoma < 1.0 cm on gadoxetate disodium-enhanced magnetic resonance imaging

OBJECTIVES

We aimed to develop and evaluate a modified Liver Imaging Reporting and Data System (LI-RADS) version 2018 using significant ancillary features for diagnosing hepatocellular carcinoma (HCC) < 1.0 cm on gadoxetate disodium-enhanced magnetic resonance imaging (MRI).

METHODS

Patients who underwent preoperative gadoxetate disodium-enhanced MRI for focal solid nodules < 2.0 cm within 1 month of MRI between January 2016 and December 2020 were retrospectively analyzed. Major and ancillary features were compared between HCCs of < 1.0 cm and 1.0-1.9 cm using the chi-square test. Significant ancillary features associated with HCC < 1.0 cm were determined by univariable and multivariable logistic regression analysis. The sensitivity and specificity of LR-5 were compared between LI-RADS v2018 and our modified LI-RADS (applying the significant ancillary feature) using generalized estimating equations.

RESULTS

Of 796 included nodules, 248 were < 1.0 cm and 548 were 1.0-1.9 cm. HCC < 1.0 cm less frequently showed an enhancing capsule (7.1% vs. 31.1%, p < .001) and threshold growth (0% vs. 8.3%, p = .007) than HCC of 1.0-1.9 cm. Restricted diffusion was the only ancillary feature significant for diagnosing HCC < 1.0 cm (adjusted odds ratio = 11.50, p < .001). In the diagnosis of HCC, our modified LI-RADS using restricted diffusion had significantly higher sensitivity than LI-RADS v2018 (61.8% vs. 53.5%, p < .001), with similar specificity (97.3% vs. 97.8%, p = .157).

CONCLUSION

Restricted diffusion was the only significant independent ancillary feature for diagnosing HCC < 1.0 cm. Our modified LI-RADS using restricted diffusion can improve the sensitivity for HCC < 1.0 cm.

KEY POINTS

• The imaging features of hepatocellular carcinoma (HCC) < 1.0 cm differed from those of HCC of 1.0-1.9 cm. • Restricted diffusion was the only significant independent ancillary feature for HCC < 1.0 cm. • Modified Liver Imaging Reporting and Data System (LI-RADS) with the addition of restricted diffusion can improve the sensitivity for HCC < 1.0 cm.

Quality Assessment of Ultrasound and Magnetic Resonance Imaging for Hepatocellular Carcinoma Surveillance: A Systematic Review and Meta-Analysis

INTRODUCTION

To achieve early detection and curative treatment options, surveillance imaging for hepatocellular carcinoma (HCC) must remain of quality and without substantial limitations in liver visualization. However, the prevalence of limited liver visualization during HCC surveillance imaging has not been systematically assessed. Utilizing a systematic review and meta-analytic approach, we aimed to determine the prevalence of limited liver visualization during HCC surveillance imaging.

METHODS

MEDLINE and Embase electronic databases were searched to identify published data on liver visualization limitations of HCC surveillance imaging. An analysis of proportions was pooled using a generalized linear mixed model with Clopper-Pearson intervals. Risk factors were analysed using a generalized mixed model with a logit link and inverse variance weightage.

RESULTS

Of 683 records, 10 studies (7,131 patients) met inclusion criteria. Seven studies provided data on liver visualization limitations on ultrasound (US) surveillance exams: prevalence of limited liver visualization was 48.9% (95% CI: 23.5-74.9%) in the overall analysis and 59.2% (95% CI: 24.2-86.9%) in a sensitivity analysis for cirrhotic patients. Meta-regression determined that non-alcoholic fatty liver disease was associated with limited liver visualization on US. Four studies provided data for liver visualization limitations in abbreviated magnetic resonance imaging (aMRI), with inadequate visualization ranging from 5.8% to 19.0%. One study provided data for complete MRI and none for computed tomography.

CONCLUSION

A substantial proportion of US exams performed for HCC surveillance provide limited liver visualization, especially in cirrhosis, which may hinder detection of small observations. Alternative surveillance strategies including aMRI may be appropriate for patients with limited US visualization.

The interplay between sarcopenia and portal hypertension predicts ascites and mortality in cirrhosis

BACKGROUND

The role of sarcopenia in predicting decompensation other than hepatic encephalopathy is unclear. We aimed to evaluate the prognostic role of sarcopenia, assessed by computed tomography (CT), in the development of ascites and mortality in patients with advanced chronic liver disease (ACLD) outside the liver transplantation (LT) setting.

MATERIAL AND METHODS

We retrospectively evaluated ACLD patients with liver stiffness measurement (LSM) >10 kPa and an available CT scan within 6 months. Sarcopenia was defined as skeletal muscle index (SMI) <50 and <39 cm²/m², respectively, in men and women. Competing risk regression models were used to assess the variables associated with the main outcomes.

RESULTS

209 patients were included in the final analysis and sarcopenia was present in 134 (64.1%). During a median follow-up of 37 (20-63) months, 52 patients developed ascites, 24 underwent LT, and 30 died. Sarcopenia was found a predictive factor of decompensation with ascites (SHR 2.083, 95%-CI: 1.091-3.978), independently from the features of clinically significant portal hypertension (LSM≥21 kPa or portosystemic shunts). Sarcopenia (SHR: 2.744, 95%-CI: 1.105-6.816) and LSM≥21 kPa (SHR: 3.973, 95%-CI: 1.548-10.197) were independent risk factors for increased mortality.

CONCLUSIONS

Sarcopenia and portal hypertension are two major and independent risk factors for decompensation with ascites and mortality in cirrhotic patients outside the LT context.

Evaluation of Preoperative Microvascular Invasion in Hepatocellular Carcinoma Through Multidimensional Parameter Combination Modeling Based on Gd-EOB-DTPA MRI

BACKGROUND AND AIMS

The study established and compared the efficacy of the clinicoradiological model, radiomics model and clinicoradiological-radiomics hybrid model in predicting the microvascular invasion (MVI) of hepatocellular carcinoma (HCC) using gadolinium ethoxybenzyl diethylene triaminepentaacetic acid (Gd-EOB-DTPA) enhanced MRI.

METHODS

This was a study that enrolled 602 HCC patients from two institutions. Least absolute shrinkage and selection operator (Lasso) method was used to screen for the most important clinicoradiological and radiomics features that predict MVI pre-operatively. Three machine learning algorithms were used to establish the clinicoradiological, radiomics, and clinicoradiological-radiomics hybrid models. Area under the curve (AUC) of receiver operating characteristic (ROC) curves and Delong's test were used to compare and quantify the predictive performance of the models.

RESULTS

The AUCs of the clinicoradiological model in training and validation cohorts were 0.793 and 0.701, respectively. The radiomics signature of arterial phase (AP) images alone achieved satisfying predictive efficacy for MVI, with AUCs of 0.671 and 0.643 in training and validation cohort, respectively. The combination of clinicoradiological factors and fusion radiomics signature of AP and VP images achieved AUCs of 0.824 and 0.801 in training and validation cohorts, 0.812 and 0.805 in prospective validation and external validation cohorts, respectively. The hybrid model provided the best prediction results. The results of the Delong test revealed that there were statistically significant differences among the clinicoradiological-radiomics hybrid model, clinicoradiological model, and radiomics model (p<0.05).

CONCLUSIONS

The combination of clinicoradiological factors and fusion radiomics signature of AP and VP images based on Gd-EOB-DTPA-enhanced MRI can effectively predict MVI.

LI-RADS v2018: utilizing ancillary features on gadoxetic acid-enhanced MRI to improve the diagnostic performance of small hapatocellular carcinoma (≤ 20 mm)

PURPOSE

To evaluate the role of ancillary features (AFs) of Liver Imaging Reporting and Data System (LI-RADS) in the diagnostic performance of small HCC (≤ 20 mm) on gadoxetic acid-enhanced MRI.

METHODS

A total of 154 patients with 183 hepatic observations were analysed in this retrospective study. Observations were categorized using only major features (MFs) and combined MFs and AFs. Independently significant AFs were identified through logistic regression analysis, and upgraded LR-5 criteria were developed using these as new MFs. The diagnostic performance of the modified LI-RADS (mLI-RADS) was calculated and compared with that of LI-RADS v2018 using McNemar's test.

RESULTS

Restricted diffusion, transitional and hepatobiliary phase hypointensity were independently significant AFs. The mLI-RADS a, c, e, g, h and i (upgraded LR-4 lesions that were categorized using only MFs to LR-5 using a certain or any one, two, three of the above AFs as new MFs) yielded a significantly greater sensitivity than that of the LI-RADS v2018 (68.0%, 69.1%, 69.1%, 69.1%, 69.1%, 68.0% vs. 61.9%, all p < 0.05), whereas the specificities were not significantly different (84.9%, 86.0%, 84.9%, 83.7%, 84.9%, 87.2% vs. 88.4% all p > 0.05). When independently significant AFs were used to upgrade the LR-4 nodules categorized by combined MFs and AFs (mLI-RADS b, d and f), the sensitivities were improved, but the specificities were decreased (all p < 0.05).

CONCLUSIONS

Independently significant AFs may be used to upgrade an observation from LR-4 (categorized only using MFs) to LR-5, which can improve diagnostic performance for small HCC.

A new classification and regression tree algorithm: Improved diagnostic sensitivity for HCC ≤ 3.0 cm using gadoxetate disodium-enhanced MRI

PURPOSE

To develop and validate an effective algorithm, based on classification and regression tree (CART) analysis and LI-RADS features, for diagnosing HCC ≤ 3.0 cm with gadoxetate disodium‑enhanced MRI (Gd-EOB-MRI).

METHOD

We retrospectively included 299 and 90 high-risk patients with hepatic lesions ≤ 3.0 cm that underwent Gd-EOB-MRI from January 2018 to February 2021 in institution 1 (development cohort) and institution 2 (validation cohort), respectively. Through binary and multivariate regression analyses of LI-RADS features in the development cohort, we developed an algorithm using CART analysis, which comprised the targeted appearance and independently significant imaging features. On per-lesion basis, we compared the diagnostic performances of our algorithm, two previously reported CART algorithms, and LI-RADS LR-5 in development and validation cohorts.

RESULTS

Our CART algorithm, presenting as a decision tree, included targetoid appearance, HBP hypointensity, nonrim arterial phase hyperenhancement (APHE), and transitional phase hypointensity plus mild-moderate T2 hyperintensity. For definite HCC diagnosis, the overall sensitivity of our algorithm (development cohort 93.2%, validation cohort 92.5%; P < 0.006) was significantly higher than those of Jiang's algorithm modified LR-5 (defined as targetoid appearance, nonperipheral washout, restricted diffusion, and nonrim APHE) and LI-RADS LR-5, with the comparable specificity (development cohort: 84.3%, validation cohort: 86.7%; P ≥ 0.006). Our algorithm, providing the highest balanced accuracy (development cohort: 91.2%, validation cohort: 91.6%), outperformed other criteria for identifying HCCs from non-HCC lesions.

CONCLUSIONS

In high-risk patients, our CART algorithm developed with LI-RADS features showed promise for the early diagnosis of HCC ≤ 3.0 cm with Gd-EOB-MRI.

Utilization of a Machine Learning Algorithm for the Application of Ancillary Features to LI-RADS Categories LR3 and LR4 on Gadoxetate Disodium-Enhanced MRI

BACKGROUND

This study aimed to identify the important ancillary features (AFs) and determine the utilization of a machine-learning-based strategy for applying AFs for LI-RADS LR3/4 observations on gadoxetate disodium-enhanced MRI.

METHODS

We retrospectively analyzed MRI features of LR3/4 determined with only major features. Uni- and multivariate analyses and random forest analysis were performed to identify AFs associated with HCC. A decision tree algorithm of applying AFs for LR3/4 was compared with other alternative strategies using McNemar's test.

RESULTS

We evaluated 246 observations from 165 patients. In multivariate analysis, restricted diffusion and mild-moderate T2 hyperintensity showed independent associations with HCC (odds ratios: 12.4 [p < 0.001] and 2.5 [p = 0.02]). In random forest analysis, restricted diffusion is the most important feature for HCC. Our decision tree algorithm showed higher AUC, sensitivity, and accuracy (0.84, 92.0%, and 84.5%) than the criteria of usage of restricted diffusion (0.78, 64.5%, and 76.4%; all p < 0.05); however, our decision tree algorithm showed lower specificity than the criterion of usage of restricted diffusion (71.1% vs. 91.3%; p < 0.001).

CONCLUSION

Our decision tree algorithm of applying AFs for LR3/4 shows significantly increased AUC, sensitivity, and accuracy but reduced specificity. These appear to be more appropriate in certain circumstances in which there is an emphasis on the early detection of HCC.

Gadoxetic acid-enhanced MRI with a focus on LI-RADS v2018 imaging features predicts the prognosis after radiofrequency ablation in small hepatocellular carcinoma

Introduction

Gadoxetic acid-enhanced magnetic resonance imaging (MRI) contributes to evaluating the prognosis of small hepatocellular carcinoma (sHCC) following treatment. We have investigated the potential role of gadoxetic acid-enhanced MRI based on LI-RADS (Liver Imaging Reporting and Data System) v2018 imaging features in the prognosis prediction of patients with sHCC treated with radiofrequency ablation (RFA) as the first-line treatment and formulated a predictive nomogram.

Methods

A total of 204 patients with sHCC who all received RFA as the first-line therapy were enrolled. All patients had undergone gadoxetic acid-enhanced MRI examinations before RFA. Uni- and multivariable analyses for RFS were assessing using a Cox proportional hazards model. A novel nomogram was further constructed for predicting RFS. The clinical capacity of the model was validated according to calibration curves, the concordance index (C-index), and decision curve analyses.

Results

Alpha fetoprotein (AFP) > 100 ng/ml (HR, 2.006; 95% CI, 1.111-3.621; P = 0.021), rim arterial phase hyperenhancement (APHE) (HR, 2.751; 95% CI, 1.511-5.011; P = 0.001), and targetoid restriction on diffusion-weighted imaging (DWI) (HR, 3.289; 95% CI, 1.832-5.906; P < 0.001) were considered as the independent risk features for recurrence in patients with sHCC treated with RFA. The calibration curves and C-indexes (C-index values of 0.758 and 0.807) showed the superior predictive performance of the integrated nomogram in both the training and validation groups.

Discussion

The gadoxetic acid-enhanced MRI features based on LI-RADS v2018, including rim APHE, targetoid restriction on DWI, and the AFP level, are the independent risk factors of recurrence in patients with sHCC treated with RFA as the first-line therapy. The predictive clinical-radiological nomogram model was constructed for clinicians to develop individualized treatment and surveillance strategies.

Classification tree analysis to evaluate the most useful magnetic resonance image type in the differentiation between early and progressed hepatocellular carcinoma

AIM

Using classification tree analysis, we evaluated the most useful magnetic resonance (MR) image type in the differentiation between early and progressed hepatocellular carcinoma (eHCC and pHCC).

METHODS

We included pathologically proven 214 HCCs (28 eHCCs and 186 pHCCs) in 144 patients. The signal intensity of HCCs was assessed on in-phase (T1in) and opposed-phase T1-weighted images (T1op), ultrafast T2-weighted images (ufT2WI), fat-saturated T2-weighted images (fsT2WI), diffusion-weighted images (DWI), contrast enhanced T1-weighted images in the arterial phase (AP), portal venous phase (PVP), and the hepatobiliary phase. Fat content and washout were also evaluated. Fisher's exact test was performed to evaluate usefulness for the differentiation. Then, we chose MR images using binary logistic regression analysis and performed classification and regression tree analysis with them. Diagnostic performances of the classification tree were evaluated using a stratified 10-fold cross-validation method.

RESULTS

T1in, ufT2WI, fsT2WI, DWI, AP, PVP, fat content, and washout were all useful for the differentiation (p < 0.05), and AP and T1in were finally chosen for creating classification trees (p < 0.05). AP appeared in the first node in the tree. The area under the curve, sensitivity and specificity for eHCC, and balanced accuracy of the classification tree were 0.83 (95% CI 0.74-0.91), 0.64 (18/28, 95% CI 0.46-0.82), 0.94 (174/186, 95% CI 0.90-0.97), and 0.79 (95% CI 0.70-0.87), respectively.

CONCLUSIONS

AP is the most useful MR image type and T1in the second in the differentiation between eHCC and pHCC.

Percentages of Hepatocellular Carcinoma in LI-RADS Categories with CT and MRI: A Systematic Review and Meta-Analysis

Background The Liver Imaging Reporting and Data System (LI-RADS) CT and MRI algorithm applies equally to CT, MRI with extracellular contrast agents (ECA-MRI), and MRI with gadoxetate (Gx-MRI). Purpose To estimate pooled percentages of hepatocellular carcinoma (HCC) and overall malignancy for each LI-RADS category with CT and MRI. Materials and Methods MEDLINE and EMBASE databases were searched for research articles (January 2014-April 2021) reporting the percentages of observations in each LI-RADS category with use of versions 2014, 2017, or 2018. Study design, population characteristics, imaging modality, reference standard, and numbers of HCC and non-HCC malignancies in each category were recorded. A random-effects model evaluated the pooled percentage of HCC and overall malignancy for each category. Results There were 49 studies with 9620 patients and a total 11 562 observations, comprising 7921 HCCs, 1132 non-HCC malignancies, and 2509 benign entities. No HCC or non-HCC malignancies were reported with any modality in the LR-1 category. The pooled percentages of HCC for CT, ECA-MRI, and Gx-MRI, respectively, were 10%, 6%, and 1% for LR-2 (P = .16); 48%, 31%, and 38% for LR-3 (P = .42); 76%, 64%, and 77% for LR-4 (P = .62); 96%, 95%, and 96% for LR-5 (P = .76); 88%, 76%, and 78% for LR-5V or LR-TIV (tumor in vein) (P = .42); and 20%, 30%, and 35% for LR-M (P = .32). Most LR-M (93%-100%) and LR-5V or LR-TIV (99%-100%) observations were malignant, regardless of modality. Conclusion There was no difference in percentages of hepatocellular carcinoma and overall malignancy between CT, MRI with extracellular contrast agents, and MRI with gadoxetate for any Liver Imaging Reporting and Data System categories. © RSNA, 2023 Supplemental material is available for this article See also the editorial by Ronot in this issue.

Radiomics on Gadoxetate Disodium-enhanced MRI: Non-invasively Identifying Glypican 3-Positive Hepatocellular Carcinoma and Postoperative Recurrence

RATIONALE AND OBJECTIVES

To investigate the impact of preoperative gadoxetate disodium (EOB) MRI-based radiomics on predicting glypican 3 (GPC3)-positive expression and the relevant recurrence-free survival (RFS) of HCC ≤ 5 cm.

MATERIALS AND METHODS

Between January 2014 and October 2018, 259 patients with solitary HCC ≤ 5 cm who underwent hepatectomy and preoperative EOB-MRI were retrieved. Multivariate logistic regression was implemented to identify independent predictors for GPC3. By combining five feature selection strategies and three classifiers, 15 GPC3-oriented radiomics models could be constructed, the best of which with independent clinicoradiologic predictors was integrated into the comprehensive nomogram.

RESULTS

GPC3 was an independent risk factor of postoperative recrudescence for HCC. Alpha-fetoprotein >20 ng/mL, homogenous T2 signal and hypointensity on hepatobiliary phase were independently related to GPC3-positive expression in the clinicoradiologic model. With 10 features selected by support vector machines-recursive feature elimination, logistic regression-based classifier achieved the best performance among 15 radiomics models. After five-fold cross-validation, our comprehensive nomogram acquired better average area under receiver operating characteristic curves (training and validation cohorts: 0.931 vs. 0.943) than the clinicoradiologic algorithm (0.738 vs. 0.739) and the optimal radiomics model (0.943 vs. 0.931). Net reclassification indexes further demonstrated the superiority of GPC3 nomogram over clinicoradiologic and radiomics algorithms (46.54%, p < 0.001; 7.84%, p = 0.207). Meanwhile, higher radiomics score significantly shortened the median RFS (from >77.9 to 48.2 months, p = 0.044), which was analogue to that of the histological GPC3-positive phenotype (from >73.9 to 43.2 months, p < 0.001).

CONCLUSIONS

Preoperative EOB-MRI radiomics-based nomogram satisfactorily distinguished GPC3 status and outcomes of solitary HCC ≤ 5 cm.

Preoperative differentiation of hepatocellular carcinoma with peripheral rim-like enhancement from intrahepatic mass-forming cholangiocarcinoma on contrast-enhanced MRI

Purpose

The present study aimed to determine the reliable imaging features to distinguish atypical hepatocellular carcinoma (HCC) with peripheral rim-like enhancement from intrahepatic mass-forming cholangiocarcinoma (IMCC) on contrast-enhanced magnetic resonance imaging (MRI).

Methods

A total of 168 patients (130 male, 57.10 ± 10.53 years) pathological confirmed HCC or IMCC who underwent contrast-enhanced MRI between July 2019 and February 2022 were retrospectively included. Univariate and multivariate logistic regression analyses were used to determine independent differential factors for distinguishing HCC from IMCC, and the model was established. Bootstrap resampling 1000 times was used to verify the model, which was visualized by nomograms. The predictive performance of the model was evaluated based on discrimination, calibration, and clinical utility.

Results

Radiological capsule (OR 0.024, 95% CI: 0.006, 0.095, P<0.001), heterogeneous signal intensity (SI) on T1WI (OR 0.009, 95%CI: 0.001,0.056, P<0.001) were independent differential factors for predicting HCC over IMCC. A lobulated contour (OR 11.732, 95%CI: 2.928,47.007, P = 0.001), target sign on DP (OR 14.269, 95%CI: 2.849,82.106, P = 0.007), bile duct dilatation (OR 12.856, 95%CI: 2.013, P = 0.001) were independent differential factors for predicting IMCCs over HCCs. The independent differential factors constituted a model to distinguish atypical HCCs and IMCCs. The area under receiver operating characteristic (ROC) curve, sensitivity, and specificity values of the model were 0.964(0.940,0.987), 0.88, and 0.906, indicating that the model had an excellent differential diagnostic performance. The decision curve analysis (DCA) curve showed that the model obtained a better net clinical benefit.

Conclusion

The present study identified reliable imaging features for distinguishing atypical HCCs with peripheral rim-like enhancement from IMCCs on contrast-enhanced MRI. Our findings may help radiologists provide clinicians with more accurate preoperative imaging diagnoses to select appropriate treatment options.

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 Value of Contrast-Enhanced Magnetic Resonance Imaging Enhancement in the Differential Diagnosis of Hepatocellular Carcinoma and Combined Hepatocellular Cholangiocarinoma

Background

The distinction between combined hepatocellular-cholangiocarcinoma (cHCC-CC) and hepatocellular carcinoma (HCC) before the operation has an important clinical significance for optimizing the treatment plan and predicting the prognosis of patients. Magnetic resonance imaging (MRI) has been widely used in the preoperative diagnosis and evaluation of primary liver malignant tumors.

Purpose

The aim is to study the value of preoperative clinical data and enhanced MRI in the differential diagnosis of HCC and cHCC-CC and obtain independent risk factors for predicting cHCC-CC. Study type. Retrospective. Population. The clinical and imaging data of 157 HCC and 59 cHCC-CC patients confirmed by pathology were collected. Field Strength/Sequence. 1.5T; cross-sectional T1WI (gradient double echo sequence); cross-sectional T2WI (fast spin echo sequence, fat suppression); enhancement (3D LAVA technology). Assessment. The differences between the HCC and cHCC-CC patients were compared. Statistic Tests. Using the t-test, chi-square test, and logistic regression analysis, P < 0.05 was considered statistically significant.

Result

1. CHCC-CC was more likely to show multiple lesions than HCC (28.81% vs. 10.83%, P = 0.001) and more prone to microvascular invasion (MVI) (36.31% vs. 61.02%, P < 0.001). However, HCC had a higher incidence of liver cirrhosis than cHCC-CC (50.85% vs. 72.61%, P = 0.003). 2. The incidence of nonsmooth margin was higher in the cHCC-CC group (84.75% vs. 52.23%, P < 0.001). The incidence of peritumor enhancement in the arterial phase was higher in the cHCC-CC group (11.46% vs. 62.71%, P < 0.001) 3. According to the multivariate analysis, arterial peritumor enhancement (OR = 8.833,95%CI:4.033,19.346, P < 0.001) was an independent risk factor for cHCC-CC (P < 0.001)). It had high sensitivity (62.71%) and specificity (88.54%) in the diagnosis of cHCC-CC. Date Conclusions. Liver cirrhosis and the imaging findings of GD-DTPA-enhanced MRI are helpful for the differential diagnosis of HCC and cHCC-CC. In addition, the imaging sign of peritumoral enhancement in the arterial phase has high sensitivity and specificity for the diagnosis of cHCC-CC.

Portal hypertension may influence the registration of hypointensity of small hepatocellular carcinoma in the hepatobiliary phase in gadoxetic acid MR

BACKGROUND

The aim of the study was to analyze the association between the liver uptake of Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) in the hepatobiliary phase (HBP) in cirrhotic patients and the presence of clinically significant portal hypertension (CSPH), and how these features impact on hepatocellular carcinoma (HCC) detection in the HBP.

PATIENTS AND METHODS

Post-hoc analysis of a prospective cohort of 62 cirrhotic patients with newly US-detected nodule between 1-2 cm (study group). Twenty healthy subjects were used as control group. Qualitative and quantitative analysis of the liver contrast uptake in the HBP assessed by Relative Liver-Enhancement (RLE), Liver-Spleen (LSCR), Liver-Muscle (LMCR), and Liver-Kidney Contrast-Ratio (LKCR), Contrast Enhancement Index (CEI), and Hepatic Uptake (HUI), and biliary excretion, were registered. CSPH was confirmed invasively (HVPG > 10 mmHg) or by indirect parameters. The appearance of HCC at the HBP was analyzed.

RESULTS

Nineteen patients (30.6%) did not have CSPH. In 41 patients (66.1%) the final diagnosis was HCC. All indices were significantly higher in the control group, indicating a more intense HBP liver signal intensity compared to patients with cirrhosis, even if the comparison was restricted to patients with no CSPH. CSPH was associated to a lower rate of HCC hypointensity in the HBP (51.9% vs. 85.7% without CSPH, p = 0.004).

CONCLUSIONS

Liver uptake of Gd-EOB-DTPA at the HBP is decreased in cirrhosis even if the liver function is minimally impaired and it falls down significantly in patients with CSPH compromising the recognition of hypointense lesions. This fact may represent a limitation for the detection of small HCC in patients with cirrhosis and CSPH.

Modifying LI-RADS on Gadoxetate Disodium-Enhanced MRI: A Secondary Analysis of a Prospective Observational Study

BACKGROUND

The Liver Imaging Reporting and Data System (LI-RADS) is widely used for diagnosing hepatocellular carcinoma (HCC), however, with unsatisfactory sensitivity, complex ancillary features, and inadequate integration with gadoxetate disodium (EOB)-enhanced MRI.

PURPOSE

To modify LI-RADS (mLI-RADS) on EOB-MRI.

STUDY TYPE

Secondary analysis of a prospective observational study.

POPULATION

Between July 2015 and September 2018, 224 consecutive high-risk patients (median age, 51 years; range, 26-83; 180 men; training/testing sets: 169/55 patients) with 742 (median size, 13 mm; interquartile range, 7-27; 498 HCCs) LR-3/4/5 observations.

FIELD STRENGTH/SEQUENCE

3.0 T T₂ -weighted fast spin-echo, diffusion-weighted spin-echo based echo-planar, and 3D T₁ -weighted gradient echo sequences.

ASSESSMENT

Three radiologists (with 5, 5, and 10 years of experience in liver MR imaging, respectively) blinded to the reference standard (histopathology or imaging follow-up) reviewed all MR images independently. In the training set, the optimal LI-RADS version 2018 (v2018) features selected by Random Forest analysis were used to develop mLI-RADS via decision tree analysis.

STATISTICAL TESTS

In an independent testing set, diagnostic performances of mLI-RADS, LI-RADS v2018, and the Korean Liver Cancer Association (KLCA) guidelines were computed using a generalized estimating equation model and compared with McNemar's test. A two-tailed P < 0.05 was statistically significant.

RESULTS

Five features (nonperipheral "washout," restricted diffusion, nonrim arterial phase hyperenhancement [APHE], mild-moderate T2 hyperintensity, and transitional phase hypointensity) constituted mLI-RADS, and mLR-5 was nonperipheral washout coupled with either nonrim APHE or restricted diffusion. In the testing set, mLI-RADS was significantly more sensitive (72%) and accurate (80%) than LI-RADS v2018 (sensitivity, 61%; accuracy 74%; both P < 0.001) and the KLCA guidelines (sensitivity, 64%; accuracy 74%; both P < 0.001), without sacrificing positive predictive value (mLI-RADS, 94%; LI-RADS v2018, 94%; KLCA guidelines, 92%).

DATA CONCLUSION

In high-risk patients, the EOB-MRI-based mLI-RADS was simpler and more sensitive for HCC than LI-RADS v2018 while maintaining high positive predictive value.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 2.

Non-hypervascular hepatobiliary phase hypointense lesions detected in patients with hepatocellular carcinoma: a post hoc analysis of SORAMIC trial to identify risk factors for progression

OBJECTIVES

To identify clinical and imaging parameters associated with progression of non-hypervascular hepatobiliary phase hypointense lesions during follow-up in patients who received treatment for hepatocellular carcinoma.

METHODS

A total of 67 patients with 106 lesions were identified after screening 538 patients who underwent gadoxetic acid-enhanced MRI within the SORAMIC trial. All patients were allocated to the trial treatment according to the trial scheme, and 61 of 67 patients received systemic treatment with sorafenib (either alone or combined with locoregional therapies) during the trial period. Follow-up images after treatment according to trial scheme were reviewed for subsequent hypervascularization or > 1 cm size increase. The correlation between progression and several imaging and clinical parameters was assessed using univariable and multivariable analyses.

RESULTS

On a median 178 (range, 48-1072) days follow-up period, progression was encountered in 18 (16.9%) lesions in 12 (17.9%) patients. In univariable analysis size > 12.6 mm (p = 0.070), ECOG-PS (p = 0.025), hypointensity at T1-weighted imaging (p = 0.028), hyperintensity at T2-weighted imaging (p < 0.001), hyperintensity at DWI images (p = 0.007), and cirrhosis (p = 0.065) were correlated with progression during follow-up. Hyperintensity at T2 images (p = 0.011) was an independent risk factor for progression in multivariable analysis, as well as cirrhosis (p = 0.033) and ECOG-PS (p = 0.030).

CONCLUSIONS

Non-hypervascular hepatobiliary phase hypointense lesions are associated with subsequent progression after treatment in patients with HCC. T2 hyperintensity, diffusion restriction, cirrhosis, and higher ECOG-PS could identify lesions with increased risk. These factors should be considered for further diagnostic evaluation or treatment of such lesions.

KEY POINTS

• Non-hypervascular hepatobiliary phase hypointense lesions have considerable risk of progression in patients with hepatocellular carcinoma receiving treatment. • T2 hyperintensity, cirrhosis, ECOG-PS, and hyperintensity at DWI are associated with increased risk of progression. • Non-hypervascular hepatobiliary phase hypointense lesions should be considered in the decision-making process of locoregional therapies, especially in the presence of these risk factors.

Gadoxetate-Enhanced MRI as a Diagnostic Tool in the Management of Hepatocellular Carcinoma: Report from a 2020 Asia-Pacific Multidisciplinary Expert Meeting

Gadoxetate magnetic resonance imaging (MRI) is widely used in clinical practice for liver imaging. For optimal use, we must understand both its advantages and limitations. This article is the outcome of an online advisory board meeting and subsequent discussions by a multidisciplinary group of experts on liver diseases across the Asia-Pacific region, first held on September 28, 2020. Here, we review the technical considerations for the use of gadoxetate, its current role in the management of patients with hepatocellular carcinoma (HCC), and its relevance in consensus guidelines for HCC imaging diagnosis. In the latter part of this review, we examine recent evidence evaluating the impact of gadoxetate on clinical outcomes on a continuum from diagnosis to treatment decision-making and follow-up. In conclusion, we outline the potential future roles of gadoxetate MRI based on an evolving understanding of the clinical utility of this contrast agent in the management of patients at risk of, or with, HCC.

Risk Stratification and Distribution of Hepatocellular Carcinomas in CEUS and CT/MRI LI-RADS: A Meta-Analysis

Background

CEUS LI-RADS and CT/MRI LI-RADS have been used in clinical practice for several years. However, there is a lack of evidence-based study to compare the proportion of hepatocellular carcinomas (HCCs) in each category and the distribution of HCCs of these two categorization systems.

Purpose

The purpose of this study was to compare the proportion of HCCs between corresponding CEUS LI-RADS and CT/MRI LI-RADS categories and the distribution of HCCs and non-HCC malignancies in each category.

Methods

We searched PubMed, Embase, and Cochrane Central databases from January 2014 to December 2021. The proportion of HCCs and non-HCC malignancies and the corresponding sensitivity, specificity, accuracy, diagnostic odds ratio (DOR), and area under the curve (AUC) of the LR-5 and LR-M categories were determined using a random-effect model.

Results

A total of 43 studies were included. The proportion of HCCs in CEUS LR-5 was 96%, and that in CECT/MRI LR-5 was 95% (p > 0.05). The proportion of non-HCC malignancy in CEUS LR-M was lower than that of CT/MRI LR-M (35% vs. 58%, p = 0.01). The sensitivity, specificity, and accuracy of CEUS LR-5 for HCCs were 73%, 92%, and 78%, respectively, and of CT/MRI LR-5 for HCCs, 69%, 92%, and 76%, respectively.

Conclusion

With the upshift of the LI-RADS category, the proportion of HCCs increased. CEUS LR-3 has a lower risk of HCCs than CT/MRI LR-3. CEUS LR-5 and CT/MRI LR-5 have a similar diagnostic performance for HCCs. CEUS LR-M has a higher proportion of HCCs and a lower proportion of non-HCC malignancies compared with CT/MRI LR-M.

Reproducibility for Hepatocellular Carcinoma CT Radiomic Features: Influence of Delineation Variability Based on 3D-CT, 4D-CT and Multiple-Parameter MR Images

Purpose

Accurate lesion segmentation is a prerequisite for radiomic feature extraction. It helps to reduce the features variability so as to improve the reporting quality of radiomics study. In this research, we aimed to conduct a radiomic feature reproducibility test of inter-/intra-observer delineation variability in hepatocellular carcinoma using 3D-CT images, 4D-CT images and multiple-parameter MR images.

Materials and Methods

For this retrospective study, 19 HCC patients undergoing 3D-CT, 4D-CT and multiple-parameter MR scans were included in this study. The gross tumor volume (GTV) was independently delineated twice by two observers based on contrast-enhanced computed tomography (CECT), maximum intensity projection (MIP), LAVA-Flex, T2W FRFSE and DWI-EPI images. We also delineated the peritumoral region, which was defined as 0 to 5 mm radius surrounding the GTV. 107 radiomic features were automatically extracted from CECT images using 3D-Slicer software. Quartile coefficient of dispersion (QCD) and intraclass correlation coefficient (ICC) were applied to assess the variability of each radiomic feature. QCD<10% and ICC≥0.75 were considered small variations and excellent reliability. Finally, the principal component analysis (PCA) was used to test the feasibility of dimensionality reduction.

Results

For tumor tissues, the numbers of radiomic features with QCD<10% indicated no obvious inter-/intra-observer differences or discrepancies in 3D-CT, 4D-CT and multiple-parameter MR delineation. However, the number of radiomic features (mean 89) with ICC≥0.75 was the highest in the multiple-parameter MR group, followed by the 3DCT group (mean 77) and the MIP group (mean 73). The peritumor tissues also showed similar results. A total of 15 and 7 radiomic features presented excellent reproducibility and small variation in tumor and peritumoral tissues, respectively. Two robust features showed excellent reproducibility and small variation in tumor and peritumoral tissues. In addition, the values of the two features both represented statistically significant differences among tumor and peritumoral tissues (P<0.05). The PCA results indicated that the first seven principal components could preserve at least 90% of the variance of the original set of features.

Conclusion

Delineation on multiple-parameter MR images could help to improve the reproducibility of the HCC CT radiomic features and weaken the inter-/intra-observer influence.

New Liver MR Imaging Hallmarks for Small Hepatocellular Carcinoma Screening and Diagnosing in High-Risk Patients

Objective

Early detection and diagnosis of hepatocellular carcinoma (HCC) is essential for prognosis; however, the imaging hallmarks for tumor detection and diagnosis has remained the same for years despite the use of many new immerging imaging methods. This study aimed to evaluate the detection performance of hepatic nodules in high risk patients using either hepatobiliary specific contrast (HBSC) agent or extracellular contrast agent (ECA), and further to compare the diagnostic performances for hepatocellular carcinoma (HCC) using different diagnostic criteria with the histopathological results as reference standard.

Methods

This prospective study included 247 nodules in 222 patients (mean age, 53.32 ± 10.84 years; range, 22–79 years). The detection performance and imaging features of each nodule were evaluated in all MR sequences by three experienced abdominal radiologists. The detection performance of each nodule on all MR sequences were compared and further the diagnostic performance of various diagnostic criteria were evaluated.

Results

For those patients who underwent ECA-MRI, the conventional imaging hallmark of “AP + PVP and/or DP” was recommended, as 60.19% diagnostic sensitivity, 80.95% specificity and 100% lesion detection rate. Additionally, for those patients who underwent HBSC-MRI, the diagnostic criteria of “DWI + HBP” was recommended. This diagnostic criteria demonstrated, both in all tumor size and for nodules ≤2 cm, higher sensitivity (93.07 and 90.16%, all p <0.05, respectively) and slightly lower specificity (64.71 and 87.50%, all p >0.05, respectively) than that of the European Association for the Study of the Liver (EASL) criteria.

Conclusions

Different abbreviated MR protocols were recommended for patients using either ECA or HBSC. These provided imaging settings demonstrated high lesion detection rate and diagnostic performance for HCC.

Added value of enhanced CT on LR-3 and LR-4 observation of Gd-EOB-DTPA MRI for the diagnosis of HCC: are CT and MR washout features interchangeable?

OBJECTIVE

To characterize the use of portal venous or delayed phase CT as an alternative to estimate washout for the non-invasive diagnosis of hepatocellular carcinoma (HCC) on gadoxetic acid-enhanced MRI in combination with other features.

METHODS

This retrospective study included 226 observations (n = 162 patients) at high risk for HCC imaged with gadoxetic acid-enhanced MRI and enhanced liver CT between March 2015 and March 2018. Two radiologists independently evaluated two sets of images and assigned the final Liver Imaging Reporting and Data System (LI-RADS) categories by consensus using gadoxetic acid-enhanced MRI. LR-1, LR-2, LR-5, and LR-M were excluded from the study.The observations were divided using different criteria for washout: hypointensity on the portal venous phase (PVP) at MRI (criteria 1), hypointensity on PVP at MRI and/or hypoattenuation on the PVP/delayed phase at dynamic CT (criteria 2), and hypointensity on the PVP and/or hepatobiliary phase at MRI (criteria 3). The sensitivity, specificity, and accuracy for the diagnosis of HCC were analyzed for each criterion.

RESULTS

Using gadoxetic acid-enhanced, 226 lesions were diagnosed as LR-3 or LR-4 by LI-RADS. Among them, 98 and 152 had "washout" at criteria 1 and 2, respectively. For the diagnosis of HCC, criteria 2 and 3 showed significantly higher sensitivities (67.3 and 92.5%, respectively) compared with criteria 1 (35.5%) (p < 0.001). The specificity of criteria 3 (13%) was significantly lower than those of criteria 1 and 2 (40.7% and 38.4%, respectively, p < 0.001). The specificities between criteria 1 and 2 were not statistically different (p = 0.427).

CONCLUSION

Although the LI-RADS lexicon does not permit the interchange of image features among various image modalities, the sensitivity of HCC diagnosis could be improved without any decrease in specificity by adding CT image washout features.

ADVANCES IN KNOWLEDGE

Although the LI-RADS lexicon does not permit the interchange of image features among various image modalities, complementary use of dynamic CT in LR-3 or LR-4 categories on the basis of gadoxetic acid-enhanced MRI may contribute to major imaging feature.

The Value of Color Doppler Ultrasound and CT Combined with Serum AFP Examination in the Diagnosis of Hepatocellular Carcinoma

Objective

To evaluate the value of the combination of color Doppler ultrasound, computed tomography (CT), and serum tumor marker alpha-fetoprotein (AFP) examination in the diagnosis of hepatocellular carcinoma (HCC).

Methods

98 patients with HCC (malignant tumor group) and 50 liver lesion patients (benign control group), were selected for the study, and retrospective statistical methods were used to evaluate the diagnostic values of the three examinations on hepatocellular carcinoma.

Results

(1) When comparing color Doppler ultrasound blood flow parameters, the hepatic artery diameter, peak flow velocity, minimum flow velocity, and resistance index (RI) of hepatocellular carcinoma were significantly higher than those of the benign control group (P < 0.05), while the portal vein flow velocity was significantly lower than that of the control group (P < 0.05). (2) Enhanced CT imaging of hepatocellular carcinoma lesions showed mostly outflow-type enhancement changes, with high- or slightly high-density shadowing and uneven enhancement in the arterial phase, relatively low density and withdrawal of enhancement in the portal vein phase and delayed phase. (3) The serum AFP level of hepatocellular carcinoma patients was significantly higher than that of the benign control group (P < 0.01). (4) The sensitivity of color Doppler ultrasound, CT, and serum AFP alone for the diagnosis of HCC was 79.59%, 85.71%, and 66.33%, and the accuracy was 83.78%, 87.16%, and 74.32%, respectively, while the combination of the three tests could significantly increase the sensitivity to 96.94% and the accuracy to 93.92%, compared with each individual test (P < 0.01).

Conclusion

Color Doppler ultrasound and CT combined with serum AFP examination could significantly improve the sensitivity and accuracy of hepatocellular carcinoma diagnosis, reduce misdiagnosis, and facilitate early diagnosis and clinical early intervention.

Do transition and hepatobiliary phase hypointensity improve LI-RADS categorization as an alternative washout: a systematic review and meta-analysis

OBJECTIVE

The definition of washout in gadoxetate disodium-enhanced MRI (Gd-EOB-MRI) is controversial. The current Liver Imaging Reporting and Data System (LI-RADS) defines washout only in the portal venous phase on Gd-EOB-MRI, leading to low diagnostic sensitivity for HCC. We performed a meta-analysis to compare the diagnostic performance of Gd-EOB-MRI using conventional (cWO) and modified (mWO) definitions of washout.

METHODS

The PubMed and EMBASE databases were searched to identify studies published between January 1, 2010, and August 1, 2021, that compared the diagnostic performance of cWO and mWO for HCC. The mWOs added transition phase (TP) hypointensity (mWO-1), hepatobiliary phase (HBP) hypointensity (mWO-2), or both (mWO-3). The pooled sensitivity and specificity were calculated using a bivariate random-effects model. Study heterogeneity was explored by subgroup analysis and meta-regression analysis.

RESULTS

Ten comparative studies with 2391 patients were included. Compared to cWO, the overall mWO yielded significantly higher sensitivity (71% vs. 81%, p = 0.00) and lower specificity (97% vs. 93%, p = 0.01) for diagnosing HCC. The area under the curve (AUC) was 0.90 and 0.94 for the cWO and mWO, respectively. Regarding the three types of mWOs, mWO-2 showed the highest sensitivity (85%) and specificity (96%) for diagnosing HCC. mWO-2 achieved the highest AUC (0.97), followed by mWO-1 (0.90), and mWO-3 (0.89). Average reviewer experience and scanner field strength were significantly associated with study heterogeneity (p < 0.05).

CONCLUSIONS

Inclusion of TP and HBP hypointensity in the definition of washout improved the sensitivity with slightly lower specificity for diagnosing HCC in LI-RADS.

KEY POINTS

• Compared to the conventional definition of washout, studies using a modified definition had higher sensitivity (71% vs. 81%) but lower specificity (97% vs. 93%) in LI-RADS for the diagnosis of HCC. • Hepatobiliary phase hypointensity may be a preferred alternative washout for HCC diagnosis with the highest area under the curve. • Studies with experienced reviewer or 3.0T MRI showed higher sensitivity and lower specificity for diagnosing HCC when using modified washout (p < 0.05).