Introduction to the Liver Imaging Reporting and Data System for Hepatocellular Carcinoma

Enhancing deep-seated hepatocellular carcinoma detection: assessing the added value of high mechanical index setting in sonazoid-based contrast-enhanced ultrasound during post-vascular phase

PURPOSE

This retrospective study aimed to investigate the role of an additional high mechanical index (MI) setting scan during the post-vascular phase (PVP) in detecting deep-seated hepatocellular carcinoma (HCC) lesions.

METHODS

A total of 805 confirmed HCCs, which underwent Sonazoid-based contrast-enhanced ultrasound (CEUS) between January 2014 and October 2021, were included. Low MI scan was initially employed for lesion detection during the PVP, followed by high MI scan. Propensity score matching (PSM) was utilized to address confounding variables.

RESULTS

Of the 805 study lesions, 668 were detected as perfusion defects at the initial low MI setting, while 137 remained undetected. Among these 137 undetected lesions, 77 were identified at the subsequent high MI setting, whereas 60 remained undetected. Lesions that were larger (18.69 ± 11.27 mm vs. 16.55 ± 7.42 mm, p = 0.006), more superficial (6.06 ± 2.41 cm vs. 7.40 ± 2.74 cm, p < 0.001), and hypoechoic (482/668 vs. 62/137, p < 0.001) were detectable at the initial low MI setting. Male patients benefited more from the additional high MI scan (63/97 vs. 14/40, p < 0.001). Lesions identified with additional high MI were larger (18.30 ± 8.76 mm vs. 14.30 ± 4.34 mm, p < 0.001) and deeper than undetected ones (8.48 ± 2.48 cm vs. 6.02 ± 2.43 cm, p < 0.001). After PSM, depth was shown to be an independent predictor in multivariate analysis (odds ratio: 1.557, 95% confidence interval: 1.249-1.941). The depth cutoff was 7.75 cm, with a sensitivity of 0.681, specificity of 0.851, and area under the curve of 0.774.

CONCLUSIONS

The additional high MI setting scan during the PVP of Sonazoid-based CEUS leads to enhanced detection of deep-seated HCCs.

Recommended 10-Year Follow-Up Strategy for Small Hepatocellular Carcinoma After Radiofrequency Ablation: A Cost-Effectiveness Evaluation

INTRODUCTION

An optimal follow-up schedule for small (≤3-cm) hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) remains unclear in clinical guidelines. We aimed to assess the cost-effectiveness of follow-up strategies in patients with small HCC after RFA.

METHODS

In total, 11,243 patients were collected from global institutions to calculate recurrence rates. Subsequently, a Markov model covering a 10-year period was developed to compare 25 surveillance strategies involving different surveillance techniques (computed tomography [CT], magnetic resonance imaging or ultrasonography [US], and α-fetoprotein [AFP]) and intervals (3 or 6 months). The study endpoint was incremental cost-effectiveness ratio (ICER), which represented additional cost per incremental quality-adjusted life year. Sensitivity analysis was conducted by varying the values of input parameters to observe the ICER.

RESULTS

In a base case analysis, the dominant strategy was CT every 3 months during an initial 2 years, followed by semiannual CT, and then switch to biannual the combination of US screening and AFP testing after 5 years (m3_CT-m6_CT-m6_USAFP), with an ICER of $68,570.92 compared with the "not followed" strategy. One-way sensitivity analysis showed the ICER consistently remained below the willingness-to-pay threshold of $100,000.00. In a probabilistic sensitivity analysis, m3_CT-m6_CT-m6_USAFP was the most cost-effective approach in 95.6% of simulated scenarios at a willingness-to-pay threshold.

DISCUSSION

For small HCC after RFA, the recommended follow-up strategy is CT, with scans scheduled every 3 months for the first 2 years, every 6 months thereafter, and transition to biannual the combination of US screening and AFP testing after 5 years.

Hepatic Steatosis Has No Effect in Diagnosis Accuracy of LI-RADS v2018 Categorization of Hepatocellular Carcinoma in MR Imaging

BACKGROUND

In clinical practice, hepatocellular carcinoma (HCC) is widely diagnosed by using MRI, however, whether the imaging features are affected by hepatic steatosis (HS) is still unknown.

PURPOSE

To investigate and compare the differences in HCC related imaging features between with- and without-HS groups, and to further determine whether HS affects the diagnosis accuracy of Liver Imaging Reporting and Data System (LI-RADS) v2018 of HCC in MRI.

STUDY TYPE

Prospective.

SUBJECTS

One hundred and seventy-one patients (mean age, 52 ± 11 years; range, 26-83 years) including 137 men and 34 women.

FIELD STRENGTH/SEQUENCE

3.0 T, gradient echo (GRE).

ASSESSMENT

Subjects were classified as HS and non-HS groups according to MRI-proton density fat-fraction (PDFF). HS was defined as MRI-PDFF >5.6%. Three radiologists accessed HCC features and assigned LI-RADS categories in MRI independently based on LI-RADS v2018. Frequencies of HCC major features and LR categorization assignment between the two groups as well as interobserver agreement between the two radiologists were assessed.

STATISTICAL TESTS

Unpaired t-test, Chi-square test, Fisher's exact test, kappa statistic, intraclass correlation coefficient (ICC). A two-sided P value <0.05 was considered as statistically significant.

RESULTS

Major features including arterial hyperenhancement (APHE), enhancing "capsule" and nonperipheral "washout" observed between HS and non-HS groups were not significantly different (78.95% vs.78.62%, P = 0.866; 57.89% vs.52.98%, P = 0.483; and 75% vs.81.46%, P = 0.257, respectively), and the assessment of observation size showed a borderline difference (P = 0.059). No significant difference in LR-5 assignment between the two groups (69.74% vs. 72.85% for reader 1, P = 0.641; 71.05% vs. 72.19% for reader 2, P = 0.877). Interobserver agreement between the two radiologists showed almost perfect in LR-5 assignment (κ = 0.869) and size observation (ICC = 0.997).

DATA CONCLUSION

The diagnosis of HCC based on LI-RADS v2018 in MRI is of comparable performance regardless of HS, in which there is no significant difference in either the major imaging features or LR categorization.

LEVEL OF EVIDENCE

2 Technical Efficacy Stage: 2.

Prognostic Value of Liver Biomarkers in Hepatocellular Carcinoma Patients Undergoing Yttrium 90 Transarterial Radioembolization (TARE): A Retrospective Pilot Study

INTRODUCTION

Hepatocellular carcinoma (HCC) is a common cause of cancer-related death worldwide. The prognosis for HCC depends on the tumor stage, and curative therapies are more accessible in the early stages. However, effective treatments are available even in advanced stages. Transarterial radioembolization (TARE) is an alternative to transarterial chemoembolization (TACE) with reduced risk and extended disease progression time. Identifying prognostic indicators and treatment response biomarkers remains crucial. The purpose of this study was to assess the association between biomarkers related to fibrosis, liver function, and immune inflammation with tumor response to yttrium 90 transarterial radiotherapy (Y90 or TARE) in patients with HCC.

METHODS

This study enrolled patients who underwent Y90 radiotherapy for bridging, downstaging, or palliative treatment after discussion in a multidisciplinary tumor board. Using the modified Response Evaluation Criteria in Solid Tumors (mRECIST), tumor response was classified into two groups: "responders" (complete and partial response) and "non-responders" (stable and progressive disease). Logistic regression analysis was used to evaluate the association between predictors, biomarkers such as aspartate aminotransferase (AST)-to-platelet ratio index (APRI), fibrosis-4 (FIB-4), albumin-bilirubin (ALBI) score, model for end-stage liver disease (MELD) score, MELD sodium, and the systemic immune-inflammatory indexes, at established cut-offs and tumor response.

RESULTS

Of 35 patients, 22 (63%) were Whites and non-Hispanics, 32 (91%) were diagnosed with cirrhosis, and 14 (40%) of these had a viral etiology. According to mRECIST, 18 (51%) patients were classified as "responders." In multivariable logistic regression analysis, biomarkers associated with tumor response were ALBI score ≤-2.8 (odds ratio (OR) 6.1, 95%CI 2.7-14.4) and the neutrophil-to-lymphocyte ratio (NLR) ≤ 1.92 (OR 5.1, 95%CI 0.8-11.9). Biomarkers had moderate accuracy in predicting tumor response (C-statistic 0.75).

CONCLUSION

The ALBI score is a reliable predictor of treatment response following TARE. The NLR index may offer further prognostic information, and both biomarkers can be used in combination; however, further research in larger sample sets is needed.

Axial Spondyloarthritis: Does Magnetic Resonance Imaging Classification Improve Report Interpretation

OBJECTIVE

The interpretation of magnetic resonance imaging (MRI) reports is crucial for the diagnosis of axial spondyloarthritis, but the subjective nature of narrative reports can lead to varying interpretations. This study presents a validation of a novel MRI reporting system for the sacroiliac joint in clinical practice.

METHODS

A historical review was conducted on 130 consecutive patients referred by 2 rheumatologists for initial MRI assessment of possible axial spondyloarthritis. The original MRI reports were interpreted by the rheumatologists and the radiologist who originally read the images and then categorized according to the novel system. Two musculoskeletal radiologists then reinterpreted the original MRI scans using the new system, and the resulting reports were interpreted and categorized by the same rheumatologists. The quality of the new framework was assessed by comparing the interpretations of both reports.

RESULTS

Ninety-two patients met the study criteria. The rheumatologists disagreed on the categorization of the original MRI reports in 12% of cases. The rheumatologists and original radiologists disagreed on the categorization of the initial report in 23.4% of cases. In contrast, there was 100% agreement between the rheumatologists and radiologists on the categorization of the new MRI report.

CONCLUSION

The new MRI categorization system significantly improved the agreement between the clinician and radiologist in report interpretation. The system provided a standard vocabulary for reporting, reduced variability in report interpretation, and may therefore improve clinical decision-making.

Diagnostic efficacy of contrast-enhanced ultrasound, dynamic contrast-enhanced MRI combined with tumor markers AFP and DCP for primary hepatocellular carcinoma

The purpose of this study was to investigate the diagnostic efficacy of contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) combined with tumor markers alpha-fetoprotein (AFP) and des-γ-carboxyl prothrombin (DCP) for primary hepatic carcinoma (PHC). A total of 70 patients with PHC (PHC group), 42 patients with liver cyst (benign liver disease group (BLDG)) and 30 healthy people (healthy group (HG)) were selected as the research objects. CEUS and DCE-MRI were performed by American GE Vivid E9 color Doppler ultrasound system and Siemens 1.5T magnetic resonance imager, respectively. The levels of AFP and DCP were detected by ABBOTT i2000SR chemiluminescence instrument and enzyme-linked immunoassay (ELISA), respectively. In DCE-MRI examination, the portal phase and prolonged phase were mostly low signal in T1-weighted imaging (T1WI) sequence, and arterial phase was mostly high signal in T2WI sequence. In CEUS, most lesions showed hyper-enhancement in arterial phase, and hypo-enhancement in portal phase and delayed phase. AFP and DCP levels in PHC group were significantly higher than that in BLDG group and HG group. There were statistically significant differences among the three groups. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of combined diagnosis were statistically significant when compared with CEUS, AFP and DCP alone and either AFP or DCP positive. CEUS, DCE-MRI combined with tumor markers AFP and DCP have high sensitivity, specificity and accuracy in the diagnosis of PHC, which can more accurately diagnose the lesion type, provide basis for further treatment, and is worthy of clinical application.

Overview of Current Hepatocellular Carcinoma Staging Systems: Is There an Optimal System?

Multiple hepatocellular carcinoma (HCC) staging systems have been proposed and used clinically over time. These may consider clinical, pathological, radiological, or treatment response factors, depending on the model. Given the heterogeneity of HCC treatment in its different stages and the validation of the systems in different populations, they are not universal. Likewise, the improvement in diagnostic tools, as well as novel therapeutic alternatives, have made these models more complex. Despite this, some have been modified over time in line with advances in the field, and although there is no universally accepted one, each has its usefulness, strengths, and weaknesses.

Hepatocellular carcinoma surveillance - utilization, barriers and the impact of changing aetiology

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. Surveillance for HCC is critical for early detection and treatment, but fewer than one-quarter of individuals at risk of HCC undergo surveillance. Multiple failures across the screening process contribute to the underutilization of surveillance, including limited disease awareness among patients and health-care providers, knowledge gaps, and difficulty recognizing patients who are at risk. Non-alcoholic fatty liver disease and alcohol-associated liver disease are the fastest-rising causes of HCC-related death worldwide and are associated with unique barriers to surveillance. In particular, more than one-third of patients with HCC related to non-alcoholic fatty liver disease do not have cirrhosis and therefore lack a routine indication for HCC surveillance on the basis of current practice guidelines. Semi-annual abdominal ultrasound with measurement of α-fetoprotein levels is recommended for HCC surveillance, but the sensitivity of this approach for early HCC is limited, especially for patients with cirrhosis or obesity. In this Review, we discuss the current status of HCC surveillance and the remaining challenges, including the changing aetiology of liver disease. We also discuss strategies to improve the utilization and quality of surveillance for HCC.

Differences between CEUS LI-RADS and CECT LI-RADS in the diagnosis of focal liver lesions in patients at risk for HCC

OBJECTIVES

To compare the inter-modality consistency and diagnostic performances of the contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) and contrast-enhanced computed tomography (CECT) LI-RADS in patients at risk for hepatocellular carcinoma (HCC), so as to help clinicians to select a more appropriate modality to follow the focal liver lesions (FLLs).

METHODS

This retrospective study included untreated 277 FLLs from 247 patients who underwent both CEUS and CECT within 1 month. The ultrasound contrast medium used was SonoVue. FLL categories were independently assigned by two ultrasound physicians and two radiologists using CEUS LI-RADS v2017 and CECT LI-RADS v2018, respectively. The diagnostic performances of CEUS and CECT LI-RADS were evaluated using sensitivity, specificity, positive predictive value (PPV), and negative predictive value. Cohen's Kappa was employed to evaluate the concordance of the LI-RADS category.

RESULTS

The inter-modality consistency for CEUS and CECT LI-RADS was 0.31 (p < 0.001). HCC was more frequently observed in CECT LR-3 and LR-4 hepatic lesions than in CEUS (7.3% vs. 19.5%, p < 0.001). The specificity and PPV of CEUS and CECT LR-5 for the diagnosis of HCC were 89.5%, 95.0%, and 82.5%, 94.4%, respectively. The sensitivity of CEUS LR-5 + LR-M for the diagnosis of hepatic malignancies was higher than that of CECT (93.7% vs. 82.7%, p < 0.001). The specificity and PPV of CEUS LR-M for the diagnosis of non-HCC malignancies were lower than those of CECT (59.7% vs. 95.5%, p < 0.001; 23.4% vs. 70.3%, p < 0.001).

CONCLUSIONS

The inter-modality consistency between the CEUS and CECT LI-RADS categories is fair. CEUS LI-RADS was more sensitive than CECT LI-RADS in terms of identifying hepatic malignancies, but weaker in terms of separating HCC from non-HCC malignancies.

Multimodality imaging of hepatocellular carcinoma and intrahepatic cholangiocarcinoma

Hepatocellular carcinoma and intrahepatic cholangiocarcinoma are the two most common primary malignant tumors of the liver. The similarities and variations in imaging characteristics that may aid in distinguishing between these two primary tumors will be discussed and outlined in this review. Knowledge of imaging techniques that are currently available would assist in the differentiation between these primary malignancies.

Diagnostic Value of CT Delayed Phase Images Added to Gd-EOB-DTPA MRI for HCC Diagnosis in LR-3/4 Lesions

Objective

To explore the potential value of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) magnetic resonance imaging (MRI) in the diagnosis of hepatocellular carcinoma (HCC) in LR-3/4 lesions by adding computed tomography (CT) delayed images based on the Liver Imaging Reporting And Data System (LI-RADS).

Methods

The differences in clinical and imaging characteristics between hepatocellular carcinoma and non-HCC were compared, and logistic regression was used to analyze the imaging risk factors for the diagnosis of HCC. Based on the main and HCC-specific auxiliary features of Gd-EOB-DTPA MRI, the HCC diagnostic model 1 was established, and the diagnostic efficacy was analyzed. Based on model 1, delayed phase CT images were added to establish model 2 to find reliable predictors of HCC diagnosis. Receiver operating characteristic (ROC) analysis and the DeLong test were used to compare the two models.

Results

There was a significant difference in serum AFP between HCC and non-HCC (P = 0.008). Based on main and HCC-specific auxiliary features of Gd-EOB-DTPA MRI, enhancing capsule (OR = 0.197, 95% CI = 0.06-0.595, P = 0.005) and washout (OR = 10.345, 95% CI = 3.460-30.930, P < 0.001) were independent risk factors in Model 1. After adding CT delayed-phase images to build model 2, enhancing capsule (OR = 0.132, 95% CI = 0.139-0.449, P = 0.001), MRI and (or) CT washout (OR = 0.052, 95% CI = 0.016-0.172, P < 0.001) were reliable predictors for HCC diagnosis. The AUC of model 1 was 0.808, sensitivity was 63.46%, and specificity was 85.00%. The AUC of model 2 was 0.854, the sensitivity was 71.20%, and the specificity was 85.00%. DeLong test (P = 0.040) demonstrated the diagnostic efficacy of model 2 significantly superior than model 1.

Conclusion

Tumor washout and enhanced capsule are reliable factors for the diagnosis of HCC. Gd-EOB-DTPA MRI with delayed phase CT images can improve the sensitivity and diagnostic efficiency of HCC in LR-3/4 lesions on the premise of maintaining high specificity. Future studies are required to reinforce our finding.

Strategy for Accurate Diagnosis by Contrast-Enhanced Ultrasound of Focal Liver Lesions in Patients Not at High Risk for Hepatocellular Carcinoma: A Preliminary Study

OBJECTIVE

To develop an effective strategy for accurate diagnosis of focal liver lesions (FLLs) in patients with non-high risk for hepatocellular carcinoma (HCC).

METHODS

From January 2012 to December 2015, consecutive patients with non-high risk for HCC who underwent contrast-enhanced ultrasound (CEUS) were included in this retrospective double-reader study. All patients were stratified into 2 different risks (intermediate, low-risk) groups according to criteria based on clinical characteristics, known as clinical risk stratification criteria. For the intermediate-risk group, the CEUS criteria for identifying benign lesions and HCCs were constructed based on selected CEUS features. The diagnostic performance of the clinical risk stratification criteria, and CEUS criteria for identifying benign lesions and HCCs was evaluated.

RESULTS

This study included 348 FLLs in 348 patients. The sensitivity and specificity of the clinical risk stratification criteria for malignancy was 97.8 and 69.8%. Patients were classified as intermediate risk if they were male, or older than 40 years of age, or HBcAb positive, or having positive tumor markers. Otherwise, patients were classified as low risk. Among the 348 patients, 327 were in the intermediate-risk group and 21 were in the low-risk group. In the intermediate-risk group, the CEUS criteria for identifying benign lesions were any of the following features: 1) hyper/isoenhancement in the arterial phase without washout, 2) nonenhancement in all phases, 3) peripheral discontinuous globular enhancement in the arterial phase, 4) centrifugal enhancement or peripheral enhancement followed by no central enhancement, or 5) enhanced septa. The accuracy, sensitivity, and specificity of the CEUS criteria for identifying benign lesions were 94.5, 83.0, and 99.6%, respectively. Arterial phase hyperenhancement followed by mild and late washout (>60 seconds) was more common in HCC patients than in non-HCC patients (P < .001). Using arterial phase hyperenhancement followed by mild and late washout as the CEUS criteria for identifying HCCs, the sensitivity and specificity were 52.6 and 95.3%, but unfortunately, the positive predictive value was only 82.0%. For the low-risk group, no further analysis was performed due to the small sample size.

CONCLUSIONS

Initial clinical risk stratification followed by assessment of certain CEUS features appears to be a promising strategy for the accurate diagnosis of FLLs in patients not at high risk for HCC.

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.

Correlation of LI-RADS 3 or 4 Observations with Histopathologic Diagnosis in Patients with Cirrhosis

Patients with cirrhosis are high risk for developing hepatocellular carcinoma (HCC) and warrant surveillance using abdominal ultrasound and α-fetoprotein.1 Those with positive surveillance results should undergo diagnostic evaluation with multiphase computed tomography (CT) or magnetic resonance imaging (MRI). The LI-RADS system is an evidence-based system to classify observations on CT or MRI in at-risk patients, ranging from LR-1 (definite benign) to LR-5 (definite HCC), with LR-3 and LR-4 observations being intermediate risk for HCC.2 LR-3 and LR-4 observations are observed on CT or MRI in more than one-fourth of patients undergoing HCC surveillance and have a high, yet variable, risk for progression to HCC.3 Approximately one-third of patients with LR-3 observations and more than two-thirds of LR-4 observations develop HCC, and surveillance strategies vary widely in practice.4,5 Variation in radiographic appearance and natural history of these observations suggests that this may be a heterogeneous group of patients; however, their histopathology has not been well described. Herein, we correlated imaging findings and explant histopathology from liver transplant recipients with at least 1 LR-3 or LR-4 observation on CT or MRI within 6 months preceding transplantation.

Risk of Hepatocellular Carcinoma in Patients With Indeterminate (LI-RADS 3) Liver Observations

Early hepatocellular cancer (HCC) detection is associated with curative treatment and improved survival.1 The American Association for the Study of Liver Diseases recommends semiannual ultrasound and α-fetoprotein (AFP) in patients with cirrhosis, and those with abnormal results should undergo diagnostic multiphase computed tomography (CT) or magnetic resonance imaging (MRI).2 The Liver Imaging Reporting and Data System (LI-RADS) was devised to standardize reporting of liver observations in at-risk individuals, ranging from LR-1 ("definitely benign") to LR-5 ("definitely HCC''), with indeterminate observations classified as LR-3 ("intermediate probability of malignancy").3 A study among 999 cirrhosis patients found that indeterminate liver observations are common, being reported on diagnostic CT or MRI in 98 (38.3%) of 256 patients with abnormal ultrasound results.4 Prior studies have reported a wide range in HCC risk, from 4% to 31%, for LR-3 observations, so there is insufficient evidence to recommend a standardized strategy for monitoring LR-3 observations.5,6.

Diagnostic Values of the Liver Imaging Reporting and Data System in the Detection and Characterization of Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

This review was undertaken to assess the diagnostic value of the Liver Imaging Reporting and Data System (LI-RADS) in patients with a high risk of hepatocellular carcinoma (HCC). Google Scholar, PubMed, Web of Science, Embase, PROQUEST, and Cochrane Library, as the international databases, were searched with appropriate keywords. Using the binomial distribution formula, the variance of all studies was calculated, and using Stata version 16 (StataCorp LLC, College Station, TX, USA), the obtained data were analyzed. Using a random-effect meta-analysis approach, we determined the pooled sensitivity and specificity. Utilizing the funnel plot and Begg's and Egger's tests, we assessed publication bias. The results exhibited pooled sensitivity and pooled specificity of 0.80% and 0.89%, respectively, with a 95% confidence interval (CI) of 0.76-0.84 and 0.87-0.92, respectively. The 2018 version of LI-RADS showed the greatest sensitivity (0.83%; 95% CI 0.79-0.87; I ² = 80.6%; P < 0.001 for heterogeneity; T ² = 0.001). The maximum pooled specificity was detected in LI-RADS version 2014 (American College of Radiology, Reston, VA, USA; 93.0%; 95% CI 89.0-96.0; I ² = 81.7%; P < 0.001 for heterogeneity; T ² = 0.001). In this review, the results of estimated sensitivity and specificity were satisfactory. Therefore, this strategy can serve as an appropriate tool for identifying HCC.

Recall patterns and risk of primary liver cancer for subcentimeter ultrasound liver observations: a multicenter study

BACKGROUND

Patients with cirrhosis and subcentimeter lesions on liver ultrasound are recommended to undergo short-interval follow-up ultrasound because of the presumed low risk of primary liver cancer (PLC).

AIMS

The aim of this study is to characterize recall patterns and risk of PLC in patients with subcentimeter liver lesions on ultrasound.

METHODS

We conducted a multicenter retrospective cohort study among patients with cirrhosis or chronic hepatitis B infection who had subcentimeter ultrasound lesions between January 2017 and December 2019. We excluded patients with a history of PLC or concomitant lesions ≥1 cm in diameter. We used Kaplan Meier and multivariable Cox regression analyses to characterize time-to-PLC and factors associated with PLC, respectively.

RESULTS

Of 746 eligible patients, most (66.0%) had a single observation, and the median diameter was 0.7 cm (interquartile range: 0.5-0.8 cm). Recall strategies varied, with only 27.8% of patients undergoing guideline-concordant ultrasound within 3-6 months. Over a median follow-up of 26 months, 42 patients developed PLC (39 HCC and 3 cholangiocarcinoma), yielding an incidence of 25.7 cases (95% CI, 6.2-47.0) per 1000 person-years, with 3.9% and 6.7% developing PLC at 2 and 3 years, respectively. Factors associated with time-to-PLC were baseline alpha-fetoprotein >10 ng/mL (HR: 4.01, 95% CI, 1.85-8.71), platelet count ≤150 (HR: 4.90, 95% CI, 1.95-12.28), and Child-Pugh B cirrhosis (vs. Child-Pugh A: HR: 2.54, 95% CI, 1.27-5.08).

CONCLUSIONS

Recall patterns for patients with subcentimeter liver lesions on ultrasound varied widely. The low risk of PLC in these patients supports short-interval ultrasound in 3-6 months, although diagnostic CT/MRI may be warranted for high-risk subgroups such as those with elevated alpha-fetoprotein levels.

Imaging features of hepatobiliary MRI and the risk of hepatocellular carcinoma development

OBJECTIVE

This study aimed to determine whether hepatocellular carcinoma (HCC) risk and time to HCC development differ according to hepatobiliary magnetic resonance imaging (MRI) findings among people at risk for developing HCC.

MATERIALS AND METHODS

A total of 199 patients aged 40 years or older with liver cirrhosis or chronic liver disease who underwent gadoxetic acid-enhanced hepatobiliary MRI between 2011 and 2015 were analyzed. An independent radiologist retrospectively reviewed MRI findings, blinded to clinical information, and categorized them into low-risk features, high-risk features and high-risk nodules. High-risk features were defined as liver cirrhosis diagnosed by imaging. High-risk nodules were defined as LR-3 or LR-4 nodules based on LI-RADS version 2018. The primary outcome was development of HCC within 5-year of MRI evaluation.

RESULTS

HCC was diagnosed in 28 patients (14.1%). HCC development was null for those with low-risk features (n = 84). The cumulative incidence rates of HCC were 0%, 2.3%, 13.4% and 22.1% at 1-, 2-, 3- and 5-year for those with high-risk features (n= 64), and were 19.1%, 31.8%, 37.3% and 46.7% at 1-, 2-, 3- and 5-year for those with high-risk nodules (n= 51). Among 28 patients developed HCC, the median time from baseline MRI to HCC diagnosis was 33.1 months (interquartile range: 25.9-46.7 months) for high-risk feature group, and 17.3 months (interquartile range: 6.2-26.5 months) for high-risk nodule group.

CONCLUSIONS

HCC risk and time to HCC development differ according to baseline hepatobiliary MRI findings, indicating that hepatobiliary MRI findings can be used as biomarkers to differentiate HCC risk.

Clinical outcomes of patients with Liver Imaging Reporting and Data System 3 or Liver Imaging Reporting and Data System 4 observations in patients with cirrhosis: A systematic review

Patients with indeterminate liver nodules, classified as LR-3 and LR-4 observations per the Liver Imaging Reporting and Data System, are at risk of developing hepatocellular carcinoma (HCC), but risk estimates remain imprecise. We conducted a systematic review of Ovid MEDLINE, EMBASE, and Cochrane databases from inception to December 2021 to identify cohort studies examining HCC incidence among patients with LR-3 or LR-4 observations on computed tomography (CT) or magnetic resonance imaging (MRI). Predictors of HCC were abstracted from each study, when available. Of 13 total studies, nine conducted LR-3 observation-level analyses, with the proportions of incident HCC ranging from 1.2% to 12.5% at 12 months and 4.2% to 44.4% during longer study follow-up. Among three studies with patient-level analyses, 8%-22.2% of patients with LR-3 lesions developed LR-4 observations and 11.1%-24.5% developed HCC. Among nine studies conducting LR-4 observation-level analyses, incident HCC ranged from 30.8% to 44.0% at 12 months and 30.9% to 71.0% during study follow-up; conversely, 6%-42% of observations were downgraded to LR-3 or lower. Patient-level factors associated with HCC included older age, male sex, higher alpha-fetoprotein levels, viral etiology, and prior history of HCC; observation-level factors included maximum diameter, threshold growth, T2 hyperintensity, and visibility on ultrasound. Studies were limited by small sample sizes, inclusion of patients with prior HCC, short follow-up duration, and failure to account for clustering of observations in patients or competing risks of transplantation and death. LR-3 and LR-4 observations have elevated but variable risks of HCC. Higher quality studies are necessary to identify high-risk patients who warrant close CT or MRI-based follow-up.

Spontaneous regression of hepatocellular carcinoma: what three cases of regression and disease reoccurrence can tell US

Hepatocellular carcinoma (HCC) is a highly morbid disease both in the United States and worldwide. Chronic liver inflammation puts people at risk of developing HCC. As chronic liver disease prevalence increases in the United States there can be an expected rise in HCC. Spontaneous regression of HCC is a rare phenomenon but can provide much needed information on how to better understand disease characteristics and progression. The two proposed theories that may explain spontaneous regression are tumor hypoxia and immunologic reaction. In these cases, we describe 3 patients with heavy disease burden at presentation who showed spontaneous regression of cancer. The patient's characteristics correlate most with systemic immunologic reaction resulting in spontaneous regression. Unfortunately, all of these patients had disease recurrence shortly after regression. By studying patient data in cases of spontaneous regression, we can gain a better understanding of disease progression and which exogenous or endogenous factors determine HCC mortality. With this knowledge we hope to better characterize how spontaneous regression occurs, and how we can use this information to help in developing treatment options in the future.

A Narrative Review on LI-RADS Algorithm in Liver Tumors: Prospects and Pitfalls

Liver cancer is the sixth most detected tumor and the third leading cause of tumor death worldwide. Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with specific risk factors and a targeted population. Imaging plays a major role in the management of HCC from screening to post-therapy follow-up. In order to optimize the diagnostic-therapeutic management and using a universal report, which allows more effective communication among the multidisciplinary team, several classification systems have been proposed over time, and LI-RADS is the most utilized. Currently, LI-RADS comprises four algorithms addressing screening and surveillance, diagnosis on computed tomography (CT)/magnetic resonance imaging (MRI), diagnosis on contrast-enhanced ultrasound (CEUS) and treatment response on CT/MRI. The algorithm allows guiding the radiologist through a stepwise process of assigning a category to a liver observation, recognizing both major and ancillary features. This process allows for characterizing liver lesions and assessing treatment. In this review, we highlighted both major and ancillary features that could define HCC. The distinctive dynamic vascular pattern of arterial hyperenhancement followed by washout in the portal-venous phase is the key hallmark of HCC, with a specificity value close to 100%. However, the sensitivity value of these combined criteria is inadequate. Recent evidence has proven that liver-specific contrast could be an important tool not only in increasing sensitivity but also in diagnosis as a major criterion. Although LI-RADS emerges as an essential instrument to support the management of liver tumors, still many improvements are needed to overcome the current limitations. In particular, features that may clearly distinguish HCC from cholangiocarcinoma (CCA) and combined HCC-CCA lesions and the assessment after locoregional radiation-based therapy are still fields of research.

Dynamic Changes in Ultrasound Quality for Hepatocellular Carcinoma Screening in Patients With Cirrhosis

BACKGROUND & AIMS

Identifying patients in whom ultrasound may be inadequate to exclude the presence of hepatocellular carcinoma (HCC) can inform interventions to improve screening effectiveness. We aimed to characterize correlates of suboptimal ultrasound quality and changes in ultrasound quality over time in patients with cirrhosis undergoing HCC screening.

METHODS

We performed a retrospective cohort study of patients with cirrhosis who underwent ultrasound examination at 2 large health systems between July 2016 and July 2019. Exam adequacy was graded by radiologists using the LI-RADS Visualization Score (A, B, C); we evaluated changes in visualization over time among patients with >1 ultrasound exams. We performed multivariable logistic regression to identify characteristics associated with limited ultrasound visualization (scores B or C).

RESULTS

Of 2053 cirrhosis patients, 1685 (82.1%) had ultrasounds with score A, 262 (12.8%) had score B, and 106 (5.2%) had score C. Limited visualization was associated with alcohol-related or nonalcoholic fatty liver disease cirrhosis and presence of class II-III obesity. Among 1546 patients with >1 ultrasounds, 1129 (73.0%) had the same visualization score on follow-up (1046 score A, 60 score B, 23 score C). However, 255 (19.6%) of 1301 with score A at baseline had limited visualization when repeated (230 score B, 25 score C), and 130 (53.1%) of 245 patients with baseline limited visualization had good visualization when repeated.

CONCLUSIONS

Nearly 1 in 5 patients with cirrhosis had moderately-severely limited ultrasound visualization for HCC nodules, particularly those with obesity or alcohol-related or nonalcoholic fatty liver disease cirrhosis. Ultrasound quality can change between exams, including improvement in many patients with limited visualization.

Early detection of hepatocellular carcinoma: roadmap for improvement

INTRODUCTION

Hepatocellular carcinoma (HCC) has a poor prognosis, related, in part, to frequent late-stage diagnosis. Improved implementation of effective HCC surveillance is critical to reduce HCC mortality.

AREAS COVERED

We performed a targeted literature review to identify intervention targets for improving HCC surveillance effectiveness, including enriched risk stratification tools, improved surveillance tools with higher accuracy for early HCC detection, and increasing surveillance adherence.

EXPERT OPINION

HCC surveillance has been demonstrated to be efficacious in several cohort studies but has lower surveillance effectiveness in clinical practice. HCC surveillance is currently recommended in all patients with cirrhosis, and improved risk stratification using clinical risk scores, genetic scores, and novel biomarkers are important to move from a 'one-size-fits-all' strategy to one more aligned with values of precision medicine. Current surveillance modalities, ultrasound, and AFP, miss over one-third of HCC at an early stage and are associated with potential surveillance harms, underscoring a need for alternative surveillance strategies with higher accuracy. MRI- and biomarker-based surveillance strategies have promising early data in phase II studies but require validation in phase III cohorts before routine use in practice. Finally, surveillance is underused in clinical practice, highlighting a need for intervention strategies to increase utilization.

MRI-Based Radiomic Features Help Identify Lesions and Predict Histopathological Grade of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common form of liver cancer. Radiomics is a promising tool that may increase the value of magnetic resonance imaging (MRI) in the management of HCC. The purpose of our study is to develop an MRI-based radiomics approach to preoperatively detect HCC and predict its histological grade. Thirty-eight HCC patients at staging who underwent axial T2-weighted and dynamic contrast-enhanced MRI (DCE-MRI) were considered. Three-dimensional volumes of interest (VOIs) were manually placed on HCC lesions and normal hepatic tissue (HT) on arterial phase post-contrast images. Radiomic features from T2 images and arterial, portal and tardive post-contrast images from DCE-MRI were extracted by using Pyradiomics. Feature selection was performed using correlation filter, Wilcoxon-rank sum test and mutual information. Predictive models were constructed for HCC differentiation with respect to HT and HCC histopathologic grading used at each step an imbalance-adjusted bootstrap resampling (IABR) on 1000 samples. Promising results were obtained from radiomic prediction models, with best AUCs ranging from 71% to 96%. Radiomics MRI based on T2 and DCE-MRI revealed promising results concerning both HCC detection and grading. It may be a suitable tool for personalized treatment of HCC patients and could also be used to develop new prognostic biomarkers useful for HCC assessment without the need for invasive procedures.

Clinical Outcomes of Patients with Suspicious (LI-RADS 4) Liver Observations

Hepatocellular cancer (HCC) surveillance is associated with increased curative treatment and improved survival, underscoring its importance in patients with cirrhosis.¹ Surveillance is 1 step in a larger HCC screening continuum, and those with abnormal screening results must undergo diagnostic evaluation with multiphase computed tomography (CT) or magnetic resonance imaging (MRI).² The Liver Imaging Reporting and Data System (LI-RADS) classifies liver observations in at-risk patients based on risk of malignancy and HCC, with LR-5 observations having a positive predictive value exceeding 95% for HCC. However, indeterminate liver nodules (ie, LR-3 or LR-4) are commonly observed in clinical practice, associated with heterogenous HCC risk, and have large variations in practice management.^3,4 We previously reported the natural history of LR-3 observations in a multicenter cohort of patients with cirrhosis, demonstrating a high annual incidence for HCC development of 8.4 cases per 100 person-years;⁵ however, the natural history of LR-4 observations remains uncertain. Herein, we aimed to characterize clinical outcomes in patients with LR-4 observations in a multicenter cohort.

Comparative efficacy of an optimal exam between ultrasound versus abbreviated MRI for HCC screening in NAFLD cirrhosis: A prospective study

BACKGROUND

Retrospective studies report that visualisation of the liver may be severely limited using ultrasound (US), potentially contributing to diminished sensitivity for detection of hepatocellular carcinoma (HCC) among patients with nonalcoholic fatty liver disease (NAFLD) and cirrhosis, but there are limited prospective data.

AIMS

To compare liver visualisation scores prospectively for US and abbreviated hepatobiliary phase (HBP) magnetic resonance imaging (AMRI) in a cohort of participants with NAFLD cirrhosis and a clinical indication for HCC surveillance.

METHODS

This prospective multicenter study included 54 consecutive participants (67% women) with NAFLD cirrhosis who underwent contemporaneous US as well as HBP-AMRI with gadoxetic acid. Primary outcome was the proportion of imaging examinations with severe limitations in liver visualisation (visualisation score C) compared head-to-head between US and AMRI.

RESULTS

The mean (± standard deviation) age was 63.3 years (±8.4) and body mass index was 32.0 kg/m2 (±6.0). Nineteen participants (35%) had severe visualisation limitations on US, compared with 10 (19%) with AMRI, p < 0.0001. Nine (17%) participants had <90% of the liver visualised on US, compared with only 1 (2%) participant with AMRI, p < 0.0001. Obesity was a strong and independent predictor for severe visualisation limitation on US (OR 5.1, CI 1.1-23.1, p = 0.03), after adjustment for age, sex and ethnicity.

CONCLUSION

More than one-third of participants with NAFLD cirrhosis had severe visualisation limitations on US for HCC screening, compared with one-sixth on AMRI. US adequacy should be reported in all clinical studies and when suboptimal then AMRI may be considered for HCC screening.

Contrast-enhanced US diagnostic algorithm of hepatocellular carcinoma in patients with occult hepatitis B

PURPOSE

To assess the diagnostic performance of contrast-enhanced (CE) US Liver Imaging Reporting and Data System (LI-RADS) version 2017 and propose a diagnostic algorithm in diagnosing hepatocellular carcinoma (HCC) in patients with occult HBV infection (OBI).

METHODS

251 OBI patients with 251 newly diagnosed focal liver lesions were retrospectively enrolled. Each nodule was evaluated according to CEUS LI-RADS. The subgroup analyses were also performed in patients with alpha-fetoprotein (AFP) more than 20ug/L or not. Diagnostic performance of CEUS LI-RADS for diagnosing HCC was validated via sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV), respectively.

RESULTS

There were 90 HCCs (90 of 251, 35.9%), of which 2 (2.0%), 53 (53.5%), and 35 (35.4%) were classified as LR-4, LR-5, and LR-M, respectively. The sensitivity, specificity, accuracy, PPV, and NPV of CEUS LR-5 for HCC diagnosis were 58.9%, 88.8%, 78.1%, 74.6%, and 79.4%, respectively. AFP increased in 50.6% (45/89) HCCs. Using a proposed diagnostic algorithm (for OBI patients with AFP more than 20 ug/L, LR-5 nodules were diagnosed as definitely HCC), the sensitivity, specificity, accuracy, PPV, and NPV were 62.2%, 71.4%, 63.5%, 93.3%, and 22.7%, respectively. Therefore, 12.2% (30 of 246) nodules could be confirmed as HCC by CEUS without biopsy.

CONCLUSION

HCC diagnosis in patients with OBI is challenging. However, using LR-5 as a noninvasively diagnostic standard in OBI patients with AFP more than 20ug/L, HCC could be confirmed by CEUS without biopsy.

Liver Imaging Reporting and Data System: Review of Pros and Cons

The American College of Radiology has released the Liver Imaging Reporting and Data System (LI-RADS) scheme which categorizes focal liver lesions (FLLs) in patients at risk for hepatocellular carcinoma (HCC) according to the degree of risk of nodules to be HCC. It subgroups FLL in LR-1 (definitely benign), LR-2 (probably benign), LR-3 (intermediate probability of malignancy), LR-4 (probably HCC), LR-5 (definitely HCC), and LR-M (probable malignancy not specific for HCC). Computed tomography/magnetic resonance imaging (CT/MRI) and contrast enhanced ultrasound (CEUS) LI-RADS diagnostic algorithm have the goal to standardize the acquisition, interpretation, reporting, and data collection for imaging examinations in patients at risk for HCC. Nevertheless, there remain controversial issues that should be dealt with. The aim of this review is to discuss the pros and cons of the interpretation and reporting part of CT/MRI and CEUS LI-RADS diagnostic algorithm to permit future refinements of the scheme and optimize patient and nodule management.

Conceptual Model for the Hepatocellular Carcinoma Screening Continuum: Current Status and Research Agenda

Hepatocellular carcinoma (HCC) continues to have a dismal prognosis, with 5-year survival below 20%. This poor prognosis can be in part attributed to failures along the cancer screening process continuum such as underuse of screening in at risk patients and appropriate treatments for patients with HCC. Better understanding these process failures, and how they compare to those seen in other cancer types, can help inform potential intervention targets and strategies to reduce HCC-related mortality. Herein, we outline a conceptual model with several discrete steps in the HCC screening process continuum including risk assessment, screening initiation, follow-up of screening results, diagnostic evaluation, and treatment evaluation. The conceptual model illustrates how each step in the screening process is prone to delays or failure, resulting in worse outcomes such as late stage diagnosis or poor survival, and how factors at the patient, provider, and health care system levels can contribute to these failures. We compare cancer screening processes for HCC with those employed in breast and colorectal cancer screening to identify opportunities for improvement. The Translational Liver Cancer consortium was recently established by the National Cancer Institute with the goal of improving early detection of HCC. Studies designed to address failures in the HCC screening process continuum will help accomplish this goal.

Systematic review: radiomics for the diagnosis and prognosis of hepatocellular carcinoma

BACKGROUND

Advances in imaging technology have the potential to transform the early diagnosis and treatment of hepatocellular carcinoma (HCC) through quantitative image analysis. Computational "radiomic" techniques extract biomarker information from images which can be used to improve diagnosis and predict tumour biology.

AIMS

To perform a systematic review on radiomic features in HCC diagnosis and prognosis, with a focus on reporting metrics and methodologic standardisation.

METHODS

We performed a systematic review of all full-text articles published from inception through December 1, 2019. Standardised data extraction and quality assessment metrics were applied to all studies.

RESULTS

A total of 54 studies were included for analysis. Radiomic features demonstrated good discriminatory performance to differentiate HCC from other solid lesions (c-statistics 0.66-0.95), and to predict microvascular invasion (c-statistic 0.76-0.92), early recurrence after hepatectomy (c-statistics 0.71-0.86), and prognosis after locoregional or systemic therapies (c-statistics 0.74-0.81). Common stratifying features for diagnostic and prognostic radiomic tools included analyses of imaging skewness, analysis of the peritumoural region, and feature extraction from the arterial imaging phase. The overall quality of the included studies was low, with common deficiencies in both internal and external validation, standardised imaging segmentation, and lack of comparison to a gold standard.

CONCLUSIONS

Quantitative image analysis demonstrates promise as a non-invasive biomarker to improve HCC diagnosis and management. However, standardisation of protocols and outcome measurement, sharing of algorithms and analytic methods, and external validation are necessary prior to widespread application of radiomics to HCC diagnosis and prognosis in clinical practice.

LI-RADS treatment response lexicon: review, refresh and resolve with emerging data

The imaging findings after loco regional treatment of hepatocellular carcinoma are variable based on the type of treatment used, the timing interval of imaging after treatment, and the cross-sectional modality used for treatment response assessment. Liver Imaging Reporting and Data System (LI-RADS) Treatment Response Algorithm (TRA) is a relatively new standardized method of evaluating treatment response after loco regional therapy to hepatocellular carcinoma. In this article, we provide an overview of the evolution of the treatment response algorithm, its current applicability and its outlook for the future. We will review current guidelines and discuss proposed changes to the algorithm as a means to continually improve LI-RADS TRA as an assessment tool post-loco regional treatment of hepatocellular carcinoma.

Evaluation of Hepatocellular Carcinoma Treatment Response After Locoregional Therapy

Locoregional therapy (LRT) for hepatocellular carcinoma can be used alone or with other treatment modalities to reduce rates of progression, improve survival, or act as a bridge to cure. As the use of LRT expands, so too has the need for systems to evaluate treatment response, such as the World Health Organization and modified Response Evaluation Criteria In Solid Tumors systems and more recently, the Liver Imaging Reporting and Data System (LI-RADS) treatment response algorithm (TRA). Early validation results for LI-RADS TRA have been promising, and as research accrues, the TRA is expected to evolve in the near future.

Does Training in LI-RADS Version 2018 Improve Readers' Agreement with the Expert Consensus and Inter-reader Agreement in MRI Interpretation?

BACKGROUND

The Liver Imaging Reporting and Data System (LI-RADS) was established for noninvasive diagnosis for hepatocellular carcinoma (HCC). However, whether training can improve readers' agreement with the expert consensus and inter-reader agreement for final categories is still unclear.

PURPOSE

To explore training effectiveness on readers' agreement with the expert consensus and inter-reader agreement.

STUDY TYPE

Prospective.

SUBJECTS

Seventy lesions in 61 patients at risk of HCC undergoing liver MRI; 20 visiting scholars.

FIELD STRENGTH/SEQUENCE

1.5 T or 3 T, Dual-echo T₁ WI, Fast spin-echo T₂ WI, SE-EPI DWI, and Dynamic multiphase fast gradient-echo T₁ WI.

ASSESSMENT

Seventy lesions assigned LI-RADS categories of LR1-LR5, LR-M, and LR-TIV by three radiologists in consensus were randomly selected, with 10 cases for each category. The consensus opinion was the standard reference. The third radiologist delivered the training. Twenty readers reviewed images independently and assigned each an LI-RADS category both before and after the training.

STATISTICAL TESTS

Accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, receiver operating characteristic (ROC) analysis, simple and weighted kappa statistics, and Fleiss kappa statistics.

RESULTS

Before and after training: readers' AUC (areas under ROC) for LR-1-LR-5, LR-M, and LR-TIV were 0.898 vs. 0.913, 0.711 vs. 0.876, 0.747 vs. 0.860, 0.724 vs. 0.815, 0.844 vs. 0.895, 0.688 vs. 0.873, and 0.720 vs. 0.948, respectively, and all improved significantly (P < 0.05), except LR-1(P = 0.25). Inter-reader agreement between readers for LR-1-LR-5, LR-M, LR-TIV were 0.725 vs. 0.751, 0.325 vs. 0.607, 0.330 vs. 0.559, 0.284 vs. 0.488, 0.447 vs. 0.648, 0.229 vs. 0.589, and 0.362 vs. 0.852, respectively, and all increased significantly (P < 0.05). For training effectiveness on both AUC and inter-reader agreement, LR-TIV, LR-M, and LR-2 improved most, and LR-1 made the least.

DATA CONCLUSION

This study shows LI-RADS training could improve reader agreement with the expert consensus and inter-reader agreement for final categories.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 2.

Need for Systematic Magnetic Resonance Imaging Interpretation and Reporting after Partial Prostate Gland Ablation

Interpretation guidelines for prostate multiparametric magnetic resonance imaging findings in the post-ablation setting are not available yet; this poses a significant challenge for accurate risk stratification in this clinical setting. Here we propose the development and implementation of a post-ablation Prostate Imaging-Reporting and Data System that would improve patient surveillance and management after prostate ablation for localized prostate cancer.

Understanding Gaps in the Hepatocellular Carcinoma Cascade of Care: Opportunities to Improve Hepatocellular Carcinoma Outcomes

Hepatocellular carcinoma (HCC) is a leading cause of morbidity and mortality. Existing studies have highlighted significant disparities in HCC outcomes, particularly among vulnerable populations, including ethnic minorities, safety-net populations, underinsured patients, and those with low socioeconomic status and high risk behaviors. The majority of these studies have focused on HCC surveillance. Although HCC surveillance is one of the most important first steps in HCC monitoring and management, it is only one step in the complex HCC cascade of care that evolves from surveillance to diagnosis and tumor staging that leads to access to HCC therapies. In this current review, we explore the disparities that exist along this complex HCC cascade of care and further highlight potential interventions that have been implemented to improve HCC outcomes. These interventions focus on patient, provider, and system level factors and provide a potential framework for health systems to implement quality improvement initiatives to improve HCC monitoring and management.

Liver Imaging Reporting and Data System Version 2018: What Radiologists Need to Know

In this article, we aim to review Liver Imaging Reporting and Data System version 18 (LI-RADS v2018). Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy. Liver Imaging Reporting and Data System developed for standardizing interpreting, reporting, and data collection of HCC describes 5 major features for accurate HCC diagnosis and several ancillary features, some favoring HCC in particular or malignancy in general and others favoring benignity. Untreated hepatic lesions LI-RADS affords 8 unique categories based on imaging appearance on computed tomography and magnetic resonance imaging, which indicate the possibility of HCC or malignancy with or without tumor in vein. Furthermore, LI-RADS defines 4 treatment response categories for treated HCCs after different locoregional therapy. These continuous recent updates on LI-RADS improve the communication between the radiologists and the clinicians for better management and patient outcome.

Diagnostic efficacy of dynamic liver imaging using qualitative diagnostic algorithm versus LI-RADS v2018 lexicon for atypical versus classical HCC lesions: A decade of experience from a tertiary liver institute

OBJECTIVE

To analyze and evaluate the diagnostic performance of conventional diagnostic (qualitative) imaging features versus LI-RADSv2018 lexicon for indeterminate and atypical Hepatocellular carcinoma (HCC) on dynamic liver imaging with reference to histopathology.

PATIENTS AND METHODS

This retrospective study (June 2009-June 2019) evaluated the performance characteristics of conventional imaging findings, versus the Liver Imaging Reporting and Data System (LIRADS) v2018, for interpretation of indeterminate and atypical HCC, in patients who underwent subsequent histopathological analysis (gold standard). A total of 100,457 dynamic hepatobiliary CT and MR examinations were performed over ten years at our institute. Using current international imaging guidelines, 3218 patients were found to have suspected liver cancer lesions on imaging. Classical enhancement pattern of typical HCC was seen in 2916 of these patients. These patients did not require further biopsy. We enrolled, the remaining (n = 302) patients, who underwent biopsy, into our study group. Two radiologists, blinded to pathology findings, reviewed and classified these lesions, in consensus, according to LI-RADS® lexicon and as per 'conventional' (Indeterminate, Atypical HCC, Classical HCC, other malignancies) imaging. The histopathology diagnosis was considered as the final diagnosis. Alpha feto protein (AFP) levels amongst various subgroups were compared. Statistical analysis was performed to calculate the efficacy of LIRADS versus qualitative imaging parameters in comparison with histopathology.

RESULTS

A total of n = 302 patients, [89 % men (n = 269), mean age 57.08 ± 12.43 years] underwent biopsy for suspected liver lesions. Qualitative imaging had 92.3 % (CI 88.53-94.91) sensitivity, 41.4 % (CI 25.51-59.26) specificity, positive predictive value (PPV) of 93.7 % (CI 90.11-96.02), negative predictive value (NPV) of 36.4 % (CI 22.19-53.38), positive likelihood ratio (PLHR) of 1.575 (CI 1.40-1.77) and negative likelihood ratio of (NLHR) 0.19 (CI 0.13-0.26). It correctly classified 87.4 % of lesions diagnosed on pathology. In comparison, LI-RADS was found to have 92 % sensitivity, 55.5 % specificity, 97 % PPV, 30.3 %, NPV, PLHR 2.068 (CI 1.62-2.64), NLHR 0.15 (CI 0.11-0.18) and 89.7 % diagnostic accuracy. A total of 38 patients (17 false negative, 21 false positive lesions) had discordant diagnoses on imaging versus histopathology. The kappa agreement between LIRADs and qualitative Imaging was found to be 0.77 ± .07 (p < 0.001). LIRADS and qualitative imaging collectively had 97 % sensitivity, 30 % specificity, 91.9 % PPV, 55.6 % NPV, PLHR of 1.39 (CI 1.27-1.51) and NLHR of 0.09 (0.048-0.19) which was better than, either reporting system, independently.

CONCLUSION

It was observed that the LI-RADS v2018 lexicon with qualitative imaging as a combination technique added extra value in interpretation of atypical HCC or indeterminate lesions on dynamic CT and MRI compared to either as 'stand- alone' reporting systems.

Interobserver Agreement of Magnetic Resonance Imaging of Liver Imaging Reporting and Data System Version 2018

AIM

This study aimed to assess the interobserver agreement of magnetic resonance (MR) imaging of Liver Imaging Reporting and Data System version 2018 (LI-RADS v2018).

SUBJECTS AND METHODS

Retrospective analysis was done for 119 consecutive patients (77 male and 42 female) at risk of hepatocellular carcinoma who underwent dynamic contrast MR imaging. Image analysis was done by 2 independent and blinded readers for arterial phase hyperenhancement, washout appearance, enhancing capsule appearance, and size. Hepatic lesions were classified into 7 groups according to LI-RADS v2018.

RESULTS

There was excellent interobserver agreement of both reviewers for LR version 4 (κ = 0.887, P = 0.001) with 90.76% agreement. There was excellent interobserver agreement for nonrim arterial phase hyperenhancement (κ = 0.948; 95% confidence interval [CI], 0.89-0.99; P = 0.001), washout appearance (κ = 0.949; 95% CI, 0.89-1.0; P = 0.001); and enhancing capsule (κ = 0.848; 95% CI, 0.73-0.97; P = 0.001) and excellent reliability of size (interclass correlation, 0.99; P = 0.001). There was excellent interobserver agreement for LR-1 (κ = 1.00, P = 0.001), LR-2 (κ = 0.94, P = 0.001), LR-5 (κ = 0.839, P = 0.001), LR-M (κ = 1.00, P = 0.001), and LR-TIV (κ = 1.00; 95% CI, 1.0-1.0; P = 0.001), and good agreement for LR-3 (κ = 0.61, P = 0.001) and LR-4 (κ = 0.61, P = 0.001).

CONCLUSION

MR imaging of LI-RADS v2018 is a reliable imaging modality and reporting system that may be used for standard interpretation of hepatic focal lesions.

A proposal for a useful algorithm to diagnose small hepatocellular carcinoma on MRI

OBJECTIVE

To assess MRI features for the diagnosis of small hepatocellular carcinomas (HCCs) and especially for nodules not showing both of the typical hallmarks.

PATIENTS AND METHODS

Three hundred and sixty-four cirrhotic patients underwent liver MRI for 10-30 mm nodules suggestive of HCC. The diagnostic performances of MRI features [T1, T2; diffusion-weighted (DW) imaging signal, enhancement, capsule, fat content] were tested, both individually and in association with both typical hallmarks and as substitutions for one hallmark. The diagnostic reference was obtained using a multifactorial algorithm ensuring high specificity (Sp).

RESULTS

Four hundred and ninety-three nodules were analyzed. No alternative features, associations or substitutions outperformed the typical hallmarks for the diagnosis of HCC. For 10-20 mm nodules not displaying one of the typical hallmarks, hyperintensity on DW images was the most accurate substitutive sign, providing a sensitivity of 71.4% and Sp of 75% for nodules without arterial enhancement and sensitivity = 65.2% and Sp = 66% for nodules without washout on the portal or delayed phases. A new diagnostic algorithm, including typical hallmarks as a first step then the best-performing substitutive signs (capsule presence or DW hyperintensity) in combination with the nonmissing typical hallmark as a second step, enabled the correct classification of 77.7% of all nodules, regardless of size.

CONCLUSION

Using MRI, the typical hallmarks remain the best criteria for the diagnosis of small HCCs. However, by incorporating other MRI features, it is possible to build a simple algorithm enabling the noninvasive diagnosis of HCCs displaying both or only one of the typical hallmarks.

Controversies in the management of hepatocellular carcinoma

The management of hepatocellular carcinoma (HCC) has evolved considerably over the last decade. Surveillance of cirrhotic patients and refinements to imaging techniques have enabled a relevant proportion of patients to be diagnosed at an early stage, when effective therapies are feasible. Resection, transplantation and ablation are all options in patients with early stage HCC. Thus, there is some controversy regarding which is the best treatment approach in challenging scenarios. There have also been major developments in locoregional therapies, particularly in intra-arterial approaches. Finally, the systemic treatment for HCC has changed dramatically following the demonstration of a survival benefit with sorafenib; there are currently several first-line (sorafenib and lenvatinib) and second-line (regorafenib, cabozantinib and ramucirumab) treatments that have shown a survival benefit. Expectations for immune checkpoint inhibitors are high, with the results of the ongoing phase III trials eagerly awaited. In this review we discuss some of the controversies in the management of HCC, focussing in particular on systemic therapy.

Detect or not to detect very early stage hepatocellular carcinoma? The western perspective

Very early stage hepatocellular carcinoma (HCC) is defined as a single tumor with the largest diameter of the lesion measuring 2 cm or less according to Barcelona Liver Cancer staging system. Detection of very early stage HCC is clinically important as it confers an excellent prognosis with the 5-year survival rates over 60 to 80% after patients receive curative treatments. While diagnosing HCC at a very early stage is crucial, it is technically challenging and may come with the physical or psychosocial harms related to diagnostic tests. It is further complicated by the fact that patients with very early stage HCC are not prioritized for liver transplant (LT) in the United States organ allocation system. When LT-eligible patients present with an indeterminate lesion measuring between 1 and 2 cm on the multiphasic computed tomography or magnetic resonance imaging, clinicians often observe patients carefully until the lesion grows up to 2 cm so that patients can be eligible to receive a Model for End-Stage Liver Disease (MELD) exception score for HCC in the United States. The European guideline recommends a routine biopsy of such lesion. In conclusion, attempting to detect very early stage HCC is difficult to achieve and controversial. Clinicians should take into account of the risk and the benefit of diagnostic tests, LT candidacy of patients and the local organ allocation system.