Diagnostic Accuracy of CEUS LI-RADS for the Characterization of Liver Nodules 20 mm or Smaller in Patients at Risk for Hepatocellular Carcinoma

Advances in liver US, CT, and MRI: moving toward the future

Over the past two decades, the epidemiology of chronic liver disease has changed with an increase in the prevalence of nonalcoholic fatty liver disease in parallel to the advent of curative treatments for hepatitis C. Recent developments provided new tools for diagnosis and monitoring of liver diseases based on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), as applied for assessing steatosis, fibrosis, and focal lesions. This narrative review aims to discuss the emerging approaches for qualitative and quantitative liver imaging, focusing on those expected to become adopted in clinical practice in the next 5 to 10 years. While radiomics is an emerging tool for many of these applications, dedicated techniques have been investigated for US (controlled attenuation parameter, backscatter coefficient, elastography methods such as point shear wave elastography [pSWE] and transient elastography [TE], novel Doppler techniques, and three-dimensional contrast-enhanced ultrasound [3D-CEUS]), CT (dual-energy, spectral photon counting, extracellular volume fraction, perfusion, and surface nodularity), and MRI (proton density fat fraction [PDFF], elastography [MRE], contrast enhancement index, relative enhancement, T1 mapping on the hepatobiliary phase, perfusion). Concurrently, the advent of abbreviated MRI protocols will help fulfill an increasing number of examination requests in an era of healthcare resource constraints.

Impact of Revision of the LR-M Criteria on the Diagnostic Performance of Contrast-Enhanced Ultrasound LI-RADS

This study was aimed at revising the LI-RADS M category (LR-M) criteria to improve the diagnostic performance categories LR-5 and LR-M of the contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) Version 2017. We enrolled 264 patients (264 nodules) with a risk for hepatocellular carcinoma (HCC). The nodules were assigned specific CEUS LI-RADS categories. Washout onset times for all nodules were noted. The diagnostic performance of LR-5 and LR-M was analyzed based on the different early washout criterion for the LR-M category. The positive predictive values in LR-5, LR-4 and LR-3 were 98.6%, 72.2% and 16.7%, respectively, and that for non-HCC malignancies in LR-M was 25.0%. Patients in the LR-M category were reclassified using 45 s as the early washout criterion. LR-5 had higher sensitivity (65.5% vs. 76.2%, p = 0.012) and area under the receiver operating characteristic curve (0.80 vs. 0.85, p = 0.001) for HCC diagnosis after reclassification. LR-M also had higher specificity (71.4% vs. 81.3%, p = 0.010) in diagnosing non-HCC malignancies after reclassification. Our findings suggest CEUS LR-5 is effective for HCC diagnosis. The use of 45 s as the time criterion of early washout for LR-M can improve LR-5 and LR-M performance in the diagnosis of HCC and non-HCC malignancies, respectively.

MicroRNAs as Diagnostic Tools in Hepatocellular Carcinoma

Liver cancer is the fourth leading cause of cancer-related deaths worldwide, with hepatocellular carcinoma (HCC) accounting for approximately 80% of all liver cancers. The serum concentration of alpha-fetoprotein (AFP) is the only validated biomarker for HCC diagnosis. MicroRNAs (miRNAs) are small non-coding RNAs of 21–30 nucleotides playing a critical role in human carcinogenesis, with types of miRNAs with oncogenic (oncomiRs) or tumor suppressor features. The altered expression of miRNAs in HCC is associated with many pathological processes, such as cancer initiation, tumor growth, apoptosis escape, promotion of migration and invasion. Moreover, circulating miRNAs have been increasingly investigated as non-invasive biomarkers for HCC diagnosis. MiRNAs’ expression patterns are altered in HCC and several single miRNAs or miRNAs panels have been found significantly up or downregulated in HCC with respect to healthy controls or non-oncological patients (cirrhotic or with viral hepatitis). However, any of the investigated miRNAs or miRNAs panels has entered clinical practice so far. This has mostly to do with lack of protocols standardization, small sample size and discrepancies in the measurement techniques. This review summarizes the major findings regarding the diagnostic role of miRNAs in HCC and their possible use together with standard biomarkers in order to obtain an early diagnosis and easier differential diagnosis from non-cancerous liver disease.

The Value of Contrast-Enhanced Ultrasound Liver Imaging Reporting and Data System in the Diagnosis of Hepatocellular Carcinoma:: A Meta-Analysis

OBJECTIVES

The aim of this study is to systematically evaluate the diagnostic ability of the contrast-enhanced ultrasound (CEUS) liver imaging reporting and data system (LI-RADS) in hepatocellular carcinoma (HCC).

METHODS

We searched relevant studies from PubMed, Medline, and Embase database. After literature search, duplicate removal, and data extraction, we calculated and analyzed the pooled sensitivity, pooled specificity, pooled odds ratios of diagnostic, pooled likelihood ratio (LR) of positive and negative, and area under the curve (AUC), accuracy, and F1 score to evaluate the diagnostic value of CEUS LI-RADS for HCC.

RESULTS

Thirteen studies and 6491 patients were included in this analysis. The pooled sensitivity and pooled specificity were 0.72 (95% confidence interval [CI], 0.70-0.73) and 0.92 (95% CI, 0.91-0.93), respectively. The positive LR was 8.02 (95% CI, 4.93-13.06) and the negative LR was 0.31 (95% CI, 0.27-0.37). The pooled diagnostic odds ratio was 27.91 (95% CI, 15.39-50.63). The overall AUC was 0.8406 and the accuracy was 0.77.

CONCLUSIONS

CEUS LI-RADS is an effective and promising method to diagnose HCC.

Comparison Between SonoVue and Sonazoid Contrast-Enhanced Ultrasound in Characterization of Focal Nodular Hyperplasia Smaller Than 3 cm

OBJECTIVES

This study aimed to compare the diagnostic efficacy of contrast-enhanced ultrasound (CEUS), including SonoVue (SV; sulfur hexafluoride; Bracco SpA, Milan, Italy) and Sonazoid (SZ; perflubutane; GE Healthcare, Oslo, Norway), and explore the differences between them in the characterization of CEUS features in focal nodular hyperplasia (FNH) smaller than 3 cm.

METHODS

This retrospective study included 31 lesions smaller than 3 cm diagnosed as FNH by CEUS between April 2019 and November 2019. Nine patients underwent SZ CEUS examinations, and 22 patients underwent SV CEUS examinations; all of them were confirmed by pathologic examinations or 2 other kinds of CEUS methods. We compared the CEUS features between SZ and SV in different phases, including arterial, portal venous, delayed, and Kupffer (SZ) phases.

RESULTS

Twenty-eight lesions were eventually diagnosed as FNH; 3 were misdiagnosed as FNH by SV CEUS. The overall diagnostic accuracy of CEUS including SZ and SV was 90.3% (28 of 31). No significant difference was found (P > .05) for the positive predictive value. Likewise, no significant difference in depicting centrifugal filling (9 of 9 versus 19 of 19), spoke wheel artery (6 of 9 versus 8 of 19), or feeding artery (2 of 9 versus 10 of 19) features was found between the contrast agents; However, SZ was significantly better at depicting the presence of a central scar than SV (5 of 9 versus 3 of 19; P = .030). Misdiagnosed cases are discussed in detail.

CONCLUSIONS

Contrast-enhanced ultrasound enables an accurate diagnosis in FNH smaller than 3 cm. Sonazoid CEUS and SV CEUS were comparable in diagnosing small FNH, and both agents were highly capable of depicting the centrifugal filling dynamic process of FNH smaller than 3 cm. Sonazoid CEUS might be better than SV CEUS at depicting a central scar.

Tumor size-based validation of contrast-enhanced ultrasound liver imaging reporting and data system (CEUS LI-RADS) 2017 for hepatocellular carcinoma characterizing

OBJECTIVES

To validate the efficacy of contrast-enhanced ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) and its major features in diagnosing hepatocellular carcinoma (HCC) of different sizes in high-risk patients.

METHODS

Between January 2014 and December 2015, a total of 545 untreated liver nodules were included. These liver nodules were divided into two groups (<20 mm and ≥20 mm). Each nodule was classified based on CEUS LI-RADS. The diagnostic performance comparison was assessed by the chi-square test, with pathology results as the golden criterion.

RESULTS

The accuracy, sensitivity, specificity, and positive predictive value (PPV) of CEUS LR-5 criteria in <20 mm group vs ≥20 mm group in diagnosing HCC were 60.5% vs 59.8%, 55.6% vs 57.6%, 85.7% vs 88.6 and 95.2% vs 98.5%, respectively, without significant difference (all p > 0.05). The accuracy, sensitivity and PPV of LR5/M for malignancy in <20 mm group were lower than in ≥20 mm group, with values of 79.1% vs 95.0%, 84.2% vs 95.7 and 91.4% vs 99.2%, respectively (p < 0.05).

CONCLUSIONS

The CEUS LI-RADS has a comparable performance for diagnosing HCC between lesions ≥ 20 mm and <20 mm. For diagnosing malignancy including HCC, it has a higher efficacy for lesions ≥ 20 mm than <20 mm.

ADVANCES IN KNOWLEDGE

1.For diagnosing HCC, CEUS LI-RADS has comparable performances between lesions ≥ 20 mm and <20 mm.2. For diagnosing malignancy including HCC, CEUS LI-RADS has a higher efficacy for lesions ≥ 20 mm than <20 mm.

Contrast-enhanced ultrasound (CEUS) in HCC diagnosis and assessment of tumor response to locoregional therapies

Hepatocellular carcinoma (HCC) is a global problem constituting the second leading cause of cancer deaths worldwide, thereby necessitating an accurate and cost-effective solution for managing care. Ultrasound is well poised to address this need due to its low cost, portability, safety, and excellent temporal resolution. The role of ultrasound for HCC screening has been well established and supported by multiple international guidelines. Similarly, contrast-enhanced ultrasound (CEUS) can be used for the characterization of focal liver lesions in high-risk populations, and standardized criteria for CEUS have been established by the American College of Radiology Liver Imaging Reporting & Data System (LI-RADS). Following HCC identification, CEUS can also be highly beneficial in treatment planning, delivery, and monitoring HCC response to locoregional therapies. Specific advantages of CEUS include providing real-time treatment guidance and improved diagnostic performance for the detection of residual tumor viability or recurrence, thereby identifying patients in need of retreatment substantially earlier than contrast-enhanced CT and MRI. This review provides a primer on ultrasound and CEUS for the screening and characterization of HCC, with an emphasis on assessing tumor response to locoregional therapies.

MR versus CEUS LI-RADS for Distinguishing Hepatocellular Carcinoma from other Hepatic Malignancies in High-Risk Patients

Distinguishing between other hepatic malignancies (OMs) and hepatocellular carcinoma (HCC) is vital to allow clinicians to determine optimal treatment and assess prognosis in patients at high risk for HCC. This study evaluated the performance of the Liver Imaging Reporting and Data System (LI-RADS) using magnetic resonance imaging (MRI) versus contrast-enhanced ultrasonography (CEUS) for differentiating HCC from OMs in patients at high risk for HCC. This retrospective study consecutively enrolled 106 high-risk patients with HCC and 52 high-risk patients with OMs. Patients underwent both MRI and CEUS, with histologic diagnosis as a reference standard. The diagnostic performance of MR versus CEUS LI-RADS was calculated and compared. The performance of the modified CEUS LI-RADS criteria was also evaluated and compared. Our research found that MRI features significantly differed between patients with OMs and those with HCC (p < 0.05), with sensitivities of 34.6%-69.2% and specificities of 83.0%-95.3% for diagnosing OMs and an LI-RADS M (LR-M): definite or probable malignancy, not specific for hepatocellular carcinoma sensitivity of 90.4% and specificity of 83.0% for diagnosing OM. CEUS features also significantly differed between patients with OM and HCC (p < 0.05), with sensitivities of 11.5%-96.2% and specificities of 23.6%-100% for diagnosing OMs, and an LR-M sensitivity of 98.1% and specificity of 84.0% for diagnosing OMs. Accuracies of category LR-M did not significantly differ between MR and CEUS LI-RADS (85.4% vs. 88.6%, p = 0.724). After reclassification of category LR-M nodules to category LR-5 if they exhibited clear intratumoral non-enhanced area boundaries and no punched-out appearance before 5 min, accuracy increased from 88.6% to 96.8% for CEUS LR-M and from 84.8% to 91.1% for CEUS LR-5. LR-M accuracies were significantly higher for the modified version of the CEUS LI-RADS than for MR LI-RADS (96.8% vs. 85.4%, respectively, p = 0.04). CEUS LI-RADS and MR LI-RADS can effectively be used to distinguish HCC from OMs. In patients at high risk of HCC, performance may be further improved by using a modified CEUS LI-RADS classification system in which category LR-M lesions are considered LR-5 if they have clear intratumoral non-enhanced area boundaries and do not have a punched-out appearance.

Can Risk Stratification Based on Ultrasound Elastography of Background Liver Assist CEUS LI-RADS in the Diagnosis of HCC?

Objective

To explore whether risk stratification based on ultrasound elastography of liver background assists contrast-enhanced ultrasound liver imaging reporting and data system (CEUS LI-RADS) in diagnosing HCC.

Materials and Methods

In total, 304 patients with focal liver lesions (FLLs) confirmed by pathology underwent CEUS and ultrasound elastography were included in this retrospective study. Patients with chronic hepatitis B (CHB, n=193) and non-CHB (n=111) were stratified by four liver stiffness measurement (LSM) thresholds. A LI-RADS category was assigned to FLLs using CEUS LI-RADS v2017. The diagnostic performance was assessed with the AUC, sensitivity, specificity, PPV, and NPV.

Results

The mean background liver stiffness of HCC patients with CHB, HCC patients without CHB and non-HCC patients without CHB were 9.72 kPa, 8.23 kPa and 4.97 kPa, respectively. The AUC, sensitivity, specificity and PPV of CEUS LI-RADS for HCC in CHB patients with LSM ≥ 5.8 kPa, ≥ 6.8 kPa, ≥ 9.1 kPa, and ≥ 10.3 kPa were high, with corresponding values of 0.745 to 0.880, 94.2% to 95.3%, 81.3% to 85.7%, and 98.1% to 98.8%, respectively. Higher AUC and specificity for HCC was observed in non-CHB patients with LSM ≥ 9.1 kPa and ≥ 10.3 kPa compared to non-CHB patients with LSM ≥ 5.8 kPa and ≥ 6.8 kPa, with corresponding values of0.964/1.000 vs 0.590/0.580, and 100%/100% vs 60%/70%, respectively.

Conclusion

CEUS LI-RADS has a good diagnostic performance in CHB patients regardless of the background liver stiffness. Furthermore, CEUS LI-RADS can be applied for non-CHB patients with a LSM ≥ 9.1 kPa.

Real-life assessment of standardized contrast-enhanced ultrasound (CEUS) and CEUS algorithms (CEUS LI-RADS®/ESCULAP) in hepatic nodules in cirrhotic patients-a prospective multicenter study

Objectives

Hepatocellular carcinoma (HCC) can be diagnosed non-invasively with contrast-enhanced ultrasound (CEUS) in cirrhosis if the characteristic pattern of arterial phase hyperenhancement followed by hypoenhancement is present. Recent studies suggest that diagnosis based on this “hyper-hypo” pattern needs further refinement. This study compares the diagnostic accuracies of standardized CEUS for HCC according to the current guideline definition and following the newly developed CEUS algorithms (CEUS LI-RADS®, ESCULAP) in a prospective multicenter real-life setting.

Methods

Cirrhotic patients with liver lesions on B-mode ultrasound were recruited prospectively from 04/2018 to 04/2019, and clinical and imaging data were collected. The CEUS standard included an additional examination point after 4–6 min in case of no washout after 3 min. The diagnostic accuracies of CEUS following the guidelines (“hyper-hypo” pattern), based on the examiner’s subjective interpretation (“CEUS subjective”), and based on the CEUS algorithms ESCULAP and CEUS LI-RADS® were compared.

Results

In total, 470 cirrhotic patients were recruited in 43 centers. The final diagnosis was HCC in 378 cases (80.4%) according to the reference standard (histology 77.4%, MRI 16.4%, CT 6.2%). The “hyper-hypo” pattern yielded 74.3% sensitivity and 63% specificity. “CEUS subjective” showed a higher diagnostic accuracy (sensitivity, 91.5%; specificity, 67.4%; positive predictive value, 92%; negative predictive value, 66%). Sensitivity was higher for ESCULAP (95%) and “CEUS subjective” (91.5%) versus CEUS LI-RADS® (65.2%; p < 0.001). Specificity was highest for CEUS LI-RADS® (78.6%; p < 0.001).

Conclusions

CEUS has an excellent diagnostic accuracy for the non-invasive diagnosis of HCC in cirrhosis. CEUS algorithms may be a helpful refinement of the “hyper-hypo” pattern defined by current HCC guidelines.

Key Points

• Contrast-enhanced ultrasound (CEUS) has a high diagnostic accuracy for the non-invasive diagnosis of hepatocellular carcinoma (HCC) in cirrhosis.

• The CEUS algorithm ESCULAP (Erlanger Synopsis for Contrast-enhanced Ultrasound for Liver lesion Assessment in Patients at risk) showed the highest sensitivity, whereas the CEUS LI-RADS® (Contrast-Enhanced UltraSound Liver Imaging Reporting and Data System) algorithm yielded the highest specificity.

• A standardized CEUS examination procedure with an additional examination point in the late phase, after 4–6 min in lesions with no washout after 3 min, is vital.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-07872-3.

Diagnostic performance of intravascular perfusion based contrast-enhanced ultrasound LI-RADS in the evaluation of hepatocellular carcinoma

BACKGROUND

The contrast-enhanced ultrasound (CEUS) liver imaging reporting and data system (LI-RADS) is a relative new algorithm for hepatocellular carcinoma (HCC) assessment.

OBJECTIVE

To validate the diagnostic efficiency of the intravascular perfusion based CEUS LI-RADS for HCC.

METHODS

Archives of 873 patients with focal liver lesions (FLLs) undergoing CEUS were reviewed, and target images were read by two sonologists independently according to the CEUS LI-RADS. The diagnostic performance was calculated and compared.

RESULTS

Assessment with reference to CEUS LI-RADS, 87 of 218 FLLs (39.9%) were categorized as LR-5, 131 of 218 FLLs (60.1%) were categorized as non-LR-5, 19 of 99 HCCs were categorized as non-LR-5, and 7 of 119 non-HCCs were categorized as LR-5. The sensitivity, specificity, AUROC, positive and negative predictive values of CEUS LI-RADS for diagnosing HCC were 80.81%(95%CI: 71.7%-88.0%), 94.1%(95%CI: 88.3%-97.6%), 0.87 (95%CI: 0.82-0.92), 91.9%(95%CI: 84.1%-96.7%), and 85.5%(95%CI: 78.3%-91.0%), respectively.

CONCLUSIONS

The diagnostic efficiency of the intravascular perfusion based CEUS LI-RADS for the evaluation of HCCs is very good.

Clinical Application of Liver Imaging Reporting and Data System for Characterizing Liver Neoplasms: A Meta-Analysis

The Liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing liver imaging in patients at risk of developing hepatocellular carcinoma (HCC). We aimed to determine the diagnostic performance of LI-RADS category 5 (LR5) for diagnosing HCC and LI-RADS category M (LRM) for characterizing other non-HCC malignancies (OM) using contrast-enhanced ultrasound (CEUS) and computed tomography (CT)/magnetic resonance imaging (MRI). Multiple databases were searched for articles evaluating the diagnostic accuracy of CEUS LI-RADS and/or CT/MRI LI-RADS. A random-effects model was adopted to synthesize the summary estimates of the diagnostic accuracy of LR5 for diagnosing HCC and LRM for characterizing OM using CEUS and CT/MRI. The pooled sensitivity and specificity of CEUS LR5 for the diagnosis of HCC were 69% and 93%, respectively. The pooled sensitivity was 67% and the specificity, 93% of CT/MRI LR5 for HCC diagnosis. There was no significant difference between the overall diagnostic accuracy for HCC diagnosis of CEUS LR5 and that of CT/MRI LR5 in terms of diagnostic odds ratio (DOR) (p = 0.55). The sensitivity was 84% with a specificity of 90% in the CEUS LRM for characterizing OM, while the sensitivity and specificity of CT/MRI LRM for characterizing OM was 63% and 95%. The DOR of CEUS LRM for characterizing OM was higher than that of CT/MRI LRM without significant difference (50.59 vs. 36.06, p = 0.34). This meta-analysis indicated that CEUS LI-RADS is qualified to characterize HCC and OM and may provide complementary information on liver nodules to CT/MRI LI-RADS.

Pathological considerations of CEUS LI-RADS: correlation with fibrosis stage and tumour histological grade

OBJECTIVES

To evaluate the influence of pathological factors, such as fibrosis stage and histological grade, on the Liver Imaging Reporting and Data System (LI-RADS) v2017 category of contrast-enhanced ultrasonography (CEUS) in patients with high risk of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Between June 2015 and December 2016, 441 consecutive patients at high risk of HCC with 460 pathologically proven HCCs were enrolled in this retrospective study. All patients underwent a CEUS examination. The major features (arterial phase hyperenhancement, late and mild washout) were assessed, and LI-RADS categories were assigned according to CEUS LI-RADS v2017. CEUS LI-RADS categories and major features were compared in different histological grades and fibrosis stages.

RESULTS

The CEUS LR-5 category was more frequently assigned in the low-grade group (151/280) than in the high-grade group (66/159) (p = 0.013), whereas the LR-TIV category was more frequently assigned in the high-grade group (36/159) than in the low-grade group (40/280) (p = 0.035). CEUS LI-RADS category was not significantly different among different fibrosis stages (p ≥ 0.05). Arterial phase hyperenhancement (APHE) and the hepatic fibrosis stage showed a significant correlation in HCCs ≥ 2 cm and the low-grade group (p = 0.027 and p = 0.003, respectively). No major features of CEUS LI-RADS showed statistically significant differences between the low- and high-grade groups (p ≥ 0.05).

CONCLUSION

Hepatic fibrosis stage can influence APHE but showed no impact on the CEUS LI-RADS classification, whereas the histological grade of HCC influenced the LR-5 and LR-TIV categories.

KEY POINTS

• Histological grade influenced CEUS LR-5 and LR-TIV category (p = 0.013 and p = 0.035 respectively). Low-grade HCCs occurred more frequently in LR-5 category whereas high-grade HCCs occurred more frequently in LR-TIV category. • Fibrosis stage shows significant influence on APHE on HCCs of the size ≥ 2 cm and low-grade group (p = 0.027 and p = 0.003, respectively). • Hepatic fibrosis stage and HCC histological grade exhibited limited impact on CEUS LI-RADS. CEUS LI-RADS may be feasible for diagnosing HCC in patients regardless of histological grade and fibrosis stage.

Combined hepatocellular-cholangiocarcinoma: can we use contrast-enhanced ultrasound Liver Imaging Reporting and Data System (LI-RADS) to predict the patient's survival?

OBJECTIVES

To evaluate the relationship between contrast-enhanced (CE) ultrasound Liver Reporting and Data System (LI-RADS) classification of combined hepatocellular-cholangiocarcinoma (cHCC-CCA) and their histopathological component predominance, and to determine if the CEUS LI-RADS category can be used to predict the patient's survival after surgical resection.

METHODS

Between January 2011 and December 2018, medical records and CEUS of patients with pathologically proven cHCC-CCA were studied. The predominance of hepatocellular carcinoma (HCC)/intrahepatic cholangiocarcinoma (ICC) component of cHCC-CCA was analyzed by histopathology. The proportion of HCC-predominant cHCC-CCA in different LI-RADS category was compared by using Fisher's exact test. Factors affecting tumor recurrence were analyzed by Cox proportional hazard model. Disease-free survival (DFS) was estimated by using Kaplan-Meier survival curve and compared by log-rank test.

RESULTS

The study included 37 cHCC-CCA patients (33 men, 4 women; average age, 50.4 ± 11.0 years) and 37 nodules (mean diameter, 6.1 ± 3.9 cm). According to CEUS LI-RADS, 62.2% (23/37), 18.9% (7/37), and 18.9% (7/37) of cHCC-CCA were classified as LR-M, LR-5, and LR-TIV, respectively. The ratio of HCC predominance in LR-5 was 100% (10/10) vs 81.5% (22/27) in the LR-M group (p = 0.591). In our population, LR-5 patients had longer DFS than LR-M and LR-TIV patients combined (median DFS: 18.0 vs 6.4 months, p = 0.016). Multiple lesions (hazard ratio, 3.1; p = 0.007), tumor size (≥ 5 cm, hazard ratio, 4.1; p = 0.003), and CEUS LI-RADS category (LR-M and LR-TIV, hazard ratio, 4.7; p = 0.011) showed independent association with shorter DFS.

CONCLUSION

cHCC-CCA characterized as LR-5 on CEUS tend to represent HCC-predominant tumors with significantly longer disease-free survival compared to cHCC-CCA categorized as LR-M and LR-TIV.

KEY POINTS

• By using the American College of Radiology contrast-enhanced ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS), majority (30/37, 81.1%) of cHCC-CCA tumors were classified as LR-M or LR-TIV and only 18.9% (7/30) of cHCC-CCA were categorized as LR-5. • Patients with CEUS LR-5 cHCC-CCA had statistically significant longer disease-free time than those with LR-M and TIV cHCC-CCA (median DFS: 18.0 vs 6.4 months, p = 0.016). • Multiple lesions (hazard ratio, 3.1; p = 0.007), tumor size (≥ 5 cm, hazard ratio, 4.1; p = 0.003), and CEUS LI-RADS category (LR-M and LR-TIV, hazard ratio, 4.7; p = 0.011) showed independent association with shorter DFS.

Contrast-enhanced ultrasound in association with serum biomarkers for differentiating combined hepatocellular-cholangiocarcinoma from hepatocellular carcinoma and intrahepatic cholangiocarcinoma

BACKGROUND

Combined hepatocellular-cholangiocarcinoma (CHC) is a rare type of primary liver cancer. Due to its complex histopathological characteristics, the imaging features of CHC can overlap with those of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC).

AIM

To investigate the possibility and efficacy of differentiating CHC from HCC and ICC by using contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) and tumor biomarkers.

METHODS

Between January 2016 and December 2019, patients with histologically confirmed CHC, ICC and HCC with chronic liver disease were enrolled. The diagnostic formula for CHC was as follows: (1) LR-5 or LR-M with elevated alpha-fetoprotein (AFP) and carbohydrate antigen 19-9 (CA19-9); (2) LR-M with elevated AFP and normal CA19-9; or (3) LR-5 with elevated CA19-9 and normal AFP. The sensitivity, specificity, accuracy and area under the receiver operating characteristic curve were calculated to determine the diagnostic value of the criteria.

RESULTS

After propensity score matching, 134 patients (mean age of 51.4 ± 9.4 years, 108 men) were enrolled, including 35 CHC, 29 ICC and 70 HCC patients. Based on CEUS LI-RADS classification, 74.3% (26/35) and 25.7% (9/35) of CHC lesions were assessed as LR-M and LR-5, respectively. The rates of elevated AFP and CA19-9 in CHC patients were 51.4% and 11.4%, respectively, and simultaneous elevations of AFP and CA19-9 were found in 8.6% (3/35) of CHC patients. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy and area under the receiver operating characteristic curve of the aforementioned diagnostic criteria for discriminating CHC from HCC and ICC were 40.0%, 89.9%, 58.3%, 80.9%, 76.9% and 0.649, respectively. When considering the reported prevalence of CHC (0.4%-14.2%), the positive predictive value and NPV were revised to 1.6%-39.6% and 90.1%-99.7%, respectively.

CONCLUSION

CHCs are more likely to be classified as LR-M than LR-5 by CEUS LI-RADS. The combination of the CEUS LI-RADS classification with serum tumor markers shows high specificity but low sensitivity for the diagnosis of CHC. Moreover, CHC could be confidently excluded with high NPV.

Diagnostic Accuracy of Contrast-Enhanced Ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) for Differentiating Between Hepatocellular Carcinoma and Other Hepatic Malignancies in High-Risk Patients: A Meta-Analysis

OBJECTIVES

 The American College of Radiology (ACR) contrast-enhanced ultrasound liver imaging reporting and data system (CEUS LI-RADS), which includes diagnostic criteria for hepatocellular carcinoma (HCC) and other hepatic malignancies (OM), is increasingly used in clinical practice. This study performed a meta-analysis to assess the diagnostic accuracy of CEUS LI-RADS for differentiating between HCC and OM in high-risk patients.

METHODS

 PubMed, Embase (Ovid), and Cochrane (CENTRAL) were searched for relevant studies. All studies that reported the percentage of HCC and OM in the LI-RADS categories were included. Random-effects models were used to calculate the pooled sensitivity and specificity, diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curve.

RESULTS

 Eight studies involving 4215 focal liver lesions were included in the final analysis. The pooled sensitivity and specificity of the LR-5 criteria for HCC were 0.71 (95 % CI, 0.69-0.72) and 0.88 (0.85-0.91), respectively, the DOR was 18.36 (7.41-45.52), and the area under the SROC curve (AUC) was 0.8128. The pooled sensitivity and specificity of the LR-M criteria for OMs were 0.85 (0.81-0.88) and 0.86 (0.85-0.87), the DOR was 27.82 (11.83-65.40), respectively, and the SROC AUC was 0.9098.

CONCLUSION

 The CEUS LI-RADS can effectively distinguish HCC from other hepatic malignancy in high-risk patients based on LR-5 criteria and LR-M criteria. However, further studies are needed for validation due to the limited number of included studies and the potential heterogeneity among the included studies.

Diagnostic efficacy of contrast-enhanced ultrasound versus MRI Liver Imaging Reporting and Data System (LI-RADS) for categorising hepatic observations in patients at risk of hepatocellular carcinoma

AIM

To investigate the diagnostic efficacy of the contrast-enhanced ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) for categorising hepatic observations in patients at risk of hepatocellular carcinoma (HCC) compared with magnetic resonance imaging (MRI) LI-RADS.

MATERIALS AND METHODS

CEUS and MRI data were analysed retrospectively according to the LI-RADS scheme. Follow-up results and pathological findings served as the reference standard. Receiver operating characteristic (ROC) curve analysis was used to reveal the area under the curve (AUC). The sensitivity, specificity, accuracy, and positive (PPV) and negative predictive values (NPV) of LR-5 for determining HCC were calculated. The intra-observer agreement of CEUS LI-RADS was also evaluated.

RESULTS

Eighty-four patients with 86 liver observations were enrolled. Forty-two observations were classified as LR-5 by CEUS and MRI, respectively. Based on the reference standard, 53 nodules were HCC. The AUCs were 0.876 for CEUS and 0.873 for MRI, without a significant difference (Z=0.050, p=0.960). The sensitivity, specificity, PPV, NPV, and accuracy of LR-5 was 75.47%, 93.94%, 95.24%, 70.45%, 82.56% with CEUS and 73.58%, 90.9%, 92.86%, 68.18%, 80.23% with MRI, respectively. There was a significant difference in specificity between CEUS and MRI (p=0.006). There was almost perfect agreement for arterial phase hyperenhancement (k=0.870), substantial agreement for washout (k=0.765) and CEUS LI-RADS category (k=0.787).

CONCLUSION

The CEUS LI-RADS scheme is an effective diagnostic tool for HCC with substantial intra-observer reliability. The diagnostic performance of CEUS LI-RADS for determining HCC was comparable to MRI LI-RADS, and the specificity of CEUS LR-5 was significantly higher.

Accuracy of contrast-enhanced ultrasound liver imaging reporting and data system: a systematic review and meta-analysis

BACKGROUND AND AIM

After the introduction of the contrast-enhanced ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS), several studies have reported on its performance, but the reported data vary considerably. Therefore, we performed a systematic review and meta-analysis to determine the diagnostic performance of CEUS LI-RADS in patients at risk for hepatocellular carcinoma (HCC) and investigate the causes of study heterogeneity.

METHODS

Original studies published until May 30, 2020, investigating the diagnostic performance of CEUS LI-RADS were identified in the MEDLINE, EMBASE, and Cochrane library databases. Study quality was assessed using the QUADAS-2 tool. Meta-analytic summary sensitivity and specificity for the diagnosis of HCC were calculated using a bivariate random-effects model. Meta-regression analysis was performed to explore the causes of study heterogeneity.

RESULTS

Of the 105 articles screened, eight studies were finally analyzed (5428 hepatic observations). The summary sensitivity and specificity of CEUS LI-RADS category 5 (LR-5) for diagnosing HCC were 73% [95% confidence interval (CI) 65-79%; I² = 93%] and 95% (95% CI 91-97%; I² = 89%), respectively. Substantial study heterogeneity was noted in both sensitivity and specificity. Study heterogeneity was significantly associated with the proportion of cases of HCC and the type of reference standard (p ≤ 0.05).

CONCLUSION

CEUS LI-RADS had high pooled specificity for diagnosing HCC but suboptimal pooled sensitivity. Substantial study heterogeneity was found, which was significantly associated with the proportion of cases of HCC and the type of reference standard.

Imaging Diagnosis of Hepatocellular Carcinoma: The Liver Imaging Reporting and Data System, Why and How?

The Liver Imaging Reporting and Data System (LI-RADS) provides standardized lexicon, technique, interpretation, and reporting of liver imaging in patients at risk for hepatocellular carcinoma (HCC). When applied to at-risk populations, LI-RADS achieves higher than 95% positive predictive value for the noninvasive diagnosis of HCC on computed tomography (CT), MRI and contrast-enhanced ultrasound (CEUS). This article focuses on similarities and differences between the CT/MRI diagnostic algorithm (CT/MRI LI-RADS) and the CEUS diagnostic algorithm (CEUS LI-RADS) to inform health care professionals for efficient and appropriate clinical decisions through the management of patients at risk.

Contrast-enhanced ultrasound liver imaging reporting and data system for diagnosing hepatocellular carcinoma: A meta-analysis

BACKGROUND & AIMS

Contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing CEUS at high risk for hepatocellular carcinoma (HCC). We performed a meta-analysis to determine the diagnostic performance of the CEUS LR-5 for HCC and the pooled proportions of HCCs in each CEUS LI-RADS category.

METHODS

We searched multiple databases for studies reporting the diagnostic accuracy of the CEUS LI-RADS. Random-effects model was used to determine summary estimates of the diagnostic performance of CEUS LR-5 and the pooled proportions of HCCs in each CEUS LI-RADS category. Risk of bias and concerns regarding applicability were evaluated with the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

Eleven studies were included in the final analysis, which consisted of 5535 observations with 3983 HCCs. The pooled per-observation sensitivity and specificity of the CEUS LR-5 for diagnosing HCC were 69% (95% confidence interval [CI], 64%-73%) and 92% (95% CI, 83%-96%) respectively. The pooled proportions of HCCs were 0% (95% CI, 0-0%) for LR-1, 1% (95% CI, 0%-4%) for CEUS LR-2, 26% (95% CI, 14%-39%) for CEUS LR-3, 77% (95% CI, 68%-86%) for CEUS LR-4, 97% (95% CI, 95%-98%) for CEUS LR-5, 57% (95% CI, 44%-69%) for CEUS LR-M and 100% (95% CI, 93%-100%) for CEUS LR-5V or TIV.

CONCLUSIONS

The CEUS LR-5 category showed moderate sensitivity and high specificity for diagnosing HCC. The proportion of HCCs was higher in the higher CEUS LI-RADS categories.

Contrast-Enhanced Ultrasonography for Screening and Diagnosis of Hepatocellular Carcinoma: A Case Series and Review of the Literature

Background: Contrast-enhanced ultrasound (CEUS) is a safe and noninvasive imaging technique that can characterize and evaluate liver lesions, and has been approved for this use in the Unites States since 2016. CEUS has been shown to be similar in accuracy to computed tomography (CT) and magnetic resonance imaging (MRI) for noninvasive diagnosis of hepatocellular carcinoma (HCC) and offers several advantages in certain patient populations who have contraindications for CT or MRI. However, CEUS has inherent limitations and has not been widely employed for evaluation of HCC. Methods: We present three retrospective cases of liver lesions in patients with cirrhosis, who underwent screening for HCC using concurrent, well-timed CT and CEUS. Results: In these cases, the liver lesions were better visualized and then diagnosed as malignancy via CEUS, whereas the lesions were best appreciated on CT only in retrospect. Conclusions: In some cirrhotic patients, a focal lesion may be more easily identifiable via CEUS than on CT and thus accurately characterized, suggesting an important and complementary role of CEUS with CT or MRI. Further studies are indicated to support the use of CEUS for the diagnosis and characterization of liver lesions in screening patients at risk for developing HCC.

Can contrast enhanced ultrasound differentiate intrahepatic cholangiocarcinoma from hepatocellular carcinoma?

BACKGROUND

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) differ in treatment and prognosis, warranting an effective differential diagnosis between them. The LR-M category in the contrast-enhanced ultrasound (CEUS) liver imaging reporting and data system (LI-RADS) was set up for lesions that are malignant but not specific to HCC. However, a substantial number of HCC cases in this category elevated the diagnostic challenge.

AIM

To investigate the possibility and efficacy of differentiating ICC from HCC classified in the LR-M category according to the CEUS LI-RADS.

METHODS

Patients with complete CEUS records together with pathologically confirmed ICC and LR-M HCC (HCC classified in the CEUS LI-RADS LR-M category) between January 2015 and October 2018 were included in this retrospective study. Each ICC was assigned a category as per the CEUS LI-RADS. The enhancement pattern, washout timing, and washout degree between the ICC and LR-M HCC were compared using the χ² test. Logistic regression analysis was used for prediction of ICC. Receiver operating characteristic (ROC) curve analysis was used to investigate the possibility of LR-M criteria and serum tumor markers in differentiating ICC from LR-M HCC.

RESULTS

A total of 228 nodules (99 ICCs and 129 LR-M HCCs) in 228 patients were included. The mean sizes of ICC and LR-M HCC were 6.3 ± 2.8 cm and 5.5 ± 3.5 cm, respectively (P = 0.03). Peripheral rim-like arterial phase hyperenhancement (APHE) was detected in 50.5% (50/99) of ICCs vs 16.3% (21/129) of LR-M HCCs (P < 0.001). Early washout was found in 93.4% (93/99) of ICCs vs 96.1% (124/129) of LR-M HCCs (P > 0.05). Marked washout was observed in 23.2% (23/99) of ICCs and 7.8% (10/129) of LR-M HCCs (P = 0.002), while this feature did not show up alone either in ICC or LR-M HCC. Homogeneous hyperenhancement was detected in 15.2% (15/99) of ICCs and 37.2% (48/129) of LR-M HCCs (P < 0.001). The logistic regression showed that rim APHE, carbohydrate antigen 19-9 (CA 19-9), and alpha fetoprotein (AFP) had significant correlations with ICC (r = 1.251, 3.074, and -2.767, respectively; P < 0.01). Rim APHE presented the best enhancement pattern for diagnosing ICC, with an area under the ROC curve (AUC) of 0.70, sensitivity of 70.4%, and specificity of 68.8%. When rim hyperenhancement was coupled with elevated CA 19-9 and normal AFP, the AUC and sensitivity improved to 0.82 and 100%, respectively, with specificity decreasing to 63.9%.

CONCLUSION

Rim APHE is a key predictor for differentiating ICC from LR-M HCC. Rim APHE plus elevated CA 19-9 and normal AFP is a strong predictor of ICC rather than LR-M HCC. Early washout and marked washout have limited value for the differentiation between the two entities.