US LI-RADS in surveillance for recurrent hepatocellular carcinoma after curative treatment.

OBJECTIVES: To investigate the performance of US LI-RADS in surveillance for recurrent hepatocellular carcinoma (RHCC) after curative treatment. MATERIALS AND METHODS: This study enrolled 644 patients between January 2018 and August 2018 as a derivation cohort, and 397 patients from September 2018 to December 2018 as a validation cohort. The US surveillance after HCC curative treatment was performed. The US LI-RADS observation categories and visualization scores were analyzed. Four criteria using US LI-RADS or Alpha-fetoprotein (AFP) as the surveillance algorithm were evaluated. The sensitivity, specificity, and negative predictive value (NPV) were calculated. RESULTS: A total of 212 (32.9%) patients in derivation cohort and 158 (39.8%) patients in validation cohort were detected to have RHCCs. The criterion of US-2/3 or AFP ≥ 20 µg/L had higher sensitivity (derivation, 96.7% vs 92.9% vs 81.1% vs 90.6%; validation, 96.2% vs 90.5% vs 80.4% vs 89.9%) and NPV (derivation, 95.7% vs 93.3% vs 88.0% vs 91.8%; validation, 94.6% vs 89.4% vs 83.6% vs 89.0%), but lower specificity (derivation, 35.9% vs 48.2% vs 67.6% vs 51.9%; validation, 43.5% vs 52.7% vs 66.1% vs 54.0%) than criterion of US-2/3, US-3, and US-3 or AFP ≥ 20 µg/L. Analysis of the visualization score subgroups confirmed that the sensitivity (89.2-97.6% vs 81.0-83.3%) and NPV(88.4-98.0% vs 80.0-83.3%) of score A and score B groups were higher than score C group in criterion of US-2/3 in both two cohorts. CONCLUSIONS: In the surveillance for RHCC, US LI-RADS with AFP had a high sensitivity and NPV when US-2/3 or AFP ≥ 20 µg/L was considered a criterion. CLINICAL RELEVANCE STATEMENT: The criterion of US-2/3 or AFP ≥ 20 µg/L improves sensitivity and NPV for RHCC surveillance, which provides a valuable reference for patients in RHCC surveillance after curative treatment. KEY POINTS: • US LI-RADS with AFP had high sensitivity and NPV in surveillance for RHCC when considering US-2/3 or AFP ≥ 20 µg/L as a criterion. • After US with AFP surveillance, patients with US-2/3 or AFP ≥ 20 µg/L should perform enhanced imaging for confirmative diagnosis. Patients with US-1 or AFP < 20 µg/L continue to repeat US with AFP surveillance. • Patients with risk factors for poor visualization scores limited the sensitivity of US surveillance in RHCC.

Shear-wave elastography combined with contrast-enhanced ultrasound algorithm for noninvasive characterization of focal liver lesions.

PURPOSE: To establish shear-wave elastography (SWE) combined with contrast-enhanced ultrasound (CEUS) algorithm (SCCA) and improve the diagnostic performance in differentiating focal liver lesions (FLLs). MATERIAL AND METHODS: We retrospectively selected patients with FLLs between January 2018 and December 2019 at the First Affiliated Hospital of Sun Yat-sen University. Histopathology was used as a standard criterion except for hemangiomas and focal nodular hyperplasia. CEUS with SonoVue (Bracco Imaging) and SCCA combining CEUS and maximum value of elastography with < 20 kPa and > 90 kPa thresholds were used for the diagnosis of FLLs. The diagnostic performance of CEUS and SCCA was calculated and compared. RESULTS: A total of 171 FLLs were included, with 124 malignant FLLs and 47 benign FLLs. The area under curve (AUC), sensitivity, and specificity in detecting malignant FLLs were 0.83, 91.94%, and 74.47% for CEUS, respectively, and 0.89, 91.94%, and 85.11% for SCCA, respectively. The AUC of SCCA was significantly higher than that of CEUS (P = 0.019). Decision curves indicated that SCCA provided greater clinical benefits. The SCCA provided significantly improved prediction of clinical outcomes, with a net reclassification improvement index of 10.64% (P = 0.018) and integrated discrimination improvement of 0.106 (P = 0.019). For subgroup analysis, we divided the FLLs into a chronic-liver-disease group (n = 88 FLLs) and a normal-liver group (n = 83 FLLs) according to the liver background. In the chronic-liver-disease group, there were no differences between the CEUS-based and SCCA diagnoses. In the normal-liver group, the AUC of SCCA and CEUS in the characterization of FLLs were 0.89 and 0.83, respectively (P = 0.018). CONCLUSION: SCCA is a feasible tool for differentiating FLLs in patients with normal liver backgrounds. Further investigations are necessary to validate the universality of this algorithm.

Preoperative prognostic value of alfa-fetoprotein density in patients with hepatocellular carcinoma undergoing radiofrequency ablation.

OBJECTIVES: To examine the prognostic value of preoperative alfa-fetoprotein (AFP) density and other clinical factors in patients undergoing percutaneous radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). METHODS: From January 2010 to December 2018, a total of 543 patients undergoing RFA for HCC meeting the Milan criteria were included at our institution. AFP density was calculated as absolute AFP pre-ablation divided by the total volume of all HCC lesions. The survival rates according to AFP density were estimated using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate Cox proportional-hazards regression analyses were used to assess predictors of overall survival (OS) and progression-free survival (PFS). RESULTS: The Kaplan-Meier 1-, 3-, and 5-year OS rates were 98.8%, 88.5%, and 70.4%, respectively, for the low AFP density group, and 98.3%, 74.9%, and 49.4%, respectively, for the high AFP density group. The corresponding PFS rates were 78.9%, 56.7%, and 40.9% (low AFP density group), and 63.6%, 40.8%, and 27.5% (high AFP density group). High AFP density was associated with significantly reduced PFS and OS (both p < 0.001). Multivariate analysis suggested that AFP density was a predictor of OS and PFS. CONCLUSIONS: Serum AFP density may serve as a promising predictor of survival in patients with HCC undergoing RFA. High AFP density could identify patients who might be prone to recurrence or progression and need close surveillance.

Identification of the origin of tumor in vein: comparison between CEUS LI-RADS v2017 and v2016 for patients at high risk.

OBJECTIVES: To compare the diagnostic performance of the Contrast-Enhanced Ultrasound (CEUS) Liver Imaging Report and Data System (LI-RADS) v2016 and v2017 in identifying the origin of tumor in vein (TIV). METHODS: From April 2014 to December 2018, focal liver lesions (FLLs) accompanied by TIV formation in patients at high risk for hepatocellular carcinoma (HCC) were enrolled. Histologic evaluation or composite imaging reference standard were served as the reference standard. Each case was categorized according to the CEUS LI-RADS v2016 and v2017, respectively. Diagnostic performance of CEUS LI-RADS v2016 and v2017 in identifying the originated tumor of TIV was validated via sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value. RESULTS: A total of 273 FLLs with TIV were analyzed finally, including 266 HCCs and 7 non-HCCs. In v2016, when adopting all TIV as LR-5V, the accuracy and PPV in identifying the originated tumor were both 97.4%. In v2017, when assigning TIV according to contiguous FLLs CEUS LI-RADS category, the accuracy and PPV were 61.9% and 99.4% in subclass of LR-5 as the diagnostic criteria of HCC, and 64.1% and 99.4% in subclass of LR-4/5 as the criteria of HCC diagnosis. There were significant differences in diagnostic accuracy between CEUS LI-RADS v2016 and v2017 in identifying the originated tumor of TIV (p < 0.001). CONCLUSIONS: CEUS LI-RADS v2016 could be better than v2017 in identifying the originated tumor of TIV.

Inter-reader agreement of CEUS LI-RADS among radiologists with different levels of experience.

OBJECTIVES: To investigate the inter-reader agreement of contrast-enhanced ultrasound (CEUS) of Liver Imaging Reporting and Data System version 2017 (LI-RADS v2017) categories among radiologists with different levels of experience. MATERIALS AND METHODS: From January 2014 to December 2014, a total of 326 patients at high risk of hepatocellular carcinoma (HCC) who underwent CEUS were included in this retrospective study. All lesions were classified according to LI-RADS v2017 by six radiologists with different levels of experiences: two residents, two fellows, and two specialists. Kappa coefficient was used to assess consistency of LI-RADS categories and major features among radiologists with different levels of experience. The diagnostic performance of HCC was described by accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC). RESULTS: Inter-reader agreement among radiologists of different experience levels was substantial agreement for arterial phase hyperenhancement, washout appearance, and early or late washout. Inter-reader agreement for LI-RADS categories was moderate to substantial. When LR-5 was used as criteria to determinate HCC, the AUC of LI-RADS for HCC was 0.67 for residents, 0.72 for fellows, and 0.78 for specialist radiologists. When compared between residents and specialists, accuracy, sensitivity, and AUC were significantly different (all p < 0.05). However, there were no significant differences in specificity, PPV, and NPV between the two groups. CONCLUSION: CEUS LI-RADS showed good diagnostic consistency among radiologists with different levels of experience, and consistency increased with experience levels. KEY POINTS: • The inter-reader agreement for LI-RADS categories was moderate to substantial agreement (κ, 0.60-0.80). • When compared between residents and specialists, accuracy, sensitivity, and AUC showed significantly different (all p < 0.05). However, there were no significant differences for specificity, PPV, and NPV between these two groups. • Among the radiologists with more than 1 year of experience, there was no significant difference in the diagnostic performance of HCC, suggesting that CEUS LI-RADS is a good standardized categorization system for high-risk patients.

Percutaneous thermal ablation of hepatic tumors: local control efficacy and risk factors for artificial ascites failure.

OBJECTIVE: To investigate the risk factors affecting the technical failure of artificial ascites (AA) formation and to evaluate the local control efficacy of percutaneous thermal ablation assisted by the AA for hepatic tumors. METHODS: A total of 341 patients with 362 hepatic tumors who underwent thermal ablation assisted by AA were reviewed retrospectively. The technical success of AA, the volume of liquid, and local efficacy after ablation were assessed. Predictive factors for the technical failure of AA formation and local tumor progression (LTP) were analyzed using univariate and multivariate analysis. RESULTS: The technical success rate of AA formation was 81.8% (296/362). The amount of fluid was higher when the tumor was located in the left lobe of the liver than when it was located in the right lobe (median 950 ml versus 700 ml, p < 0.001). Previous hepatic resection (OR: 12.63, 95% CI: 2.93-54.45, p < 0.001), ablation (OR: 6.48, 95% CI: 1.36-30.92, p = 0.019) and upper-abdomen surgery (OR: 11.34, 95% CI: 1.96-65.67, p = 0.007) were the independent risk factors of AA failure. In the AA success group, the complete ablation rate was higher and the LTP rate was lower than that in the AA failure group (98.7 versus 92.4%, p = 0.012; 8.8 versus 21.2%, p = 0.004). Multivariate analysis identified AA failure (p = 0.004), tumor size (>3.0 cm) (p = 0.002) and metastatic liver tumor (p = 0.008) as independent risk factors for LTP. CONCLUSION: History of hepatic resection, ablation and upper abdomen surgery were significant predictive factors affecting the technical failure of AA formation. Successful introduction of AA before thermal ablation can achieve better local tumor control efficacy.

Preoperative prediction of tumour deposits in rectal cancer by an artificial neural network-based US radiomics model.

OBJECTIVE: To develop a machine learning-based ultrasound (US) radiomics model for predicting tumour deposits (TDs) preoperatively. METHODS: From December 2015 to December 2017, 127 patients with rectal cancer were prospectively enrolled and divided into training and validation sets. Endorectal ultrasound (ERUS) and shear-wave elastography (SWE) examinations were conducted for each patient. A total of 4176 US radiomics features were extracted for each patient. After the reduction and selection of US radiomics features , a predictive model using an artificial neural network (ANN) was constructed in the training set. Furthermore, two models (one incorporating clinical information and one based on MRI radiomics) were developed. These models were validated by assessing their diagnostic performance and comparing the areas under the curve (AUCs) in the validation set. RESULTS: The training and validation sets included 29 (33.3%) and 11 (27.5%) patients with TDs, respectively. A US radiomics ANN model was constructed. The model for predicting TDs showed an accuracy of 75.0% in the validation cohort. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and AUC were 72.7%, 75.9%, 53.3%, 88.0% and 0.743, respectively. For the model incorporating clinical information, the AUC improved to 0.795. Although the AUC of the US radiomics model was improved compared with that of the MRI radiomics model (0.916 vs. 0.872) in the 90 patients with both ultrasound and MRI data (which included both the training and validation sets), the difference was nonsignificant (p = 0.384). CONCLUSIONS: US radiomics may be a potential model to accurately predict TDs before therapy. KEY POINTS: • We prospectively developed an artificial neural network model for predicting tumour deposits based on US radiomics that had an accuracy of 75.0%. • The area under the curve of the US radiomics model was improved than that of the MRI radiomics model (0.916 vs. 0.872), but the difference was not significant (p = 0.384). • The US radiomics-based model may potentially predict TDs accurately before therapy, but this model needs further validation with larger samples.

Thermal ablation versus hepatic resection for the treatment of liver metastases from gastrointestinal stromal tumors: a retrospective study.

Objective: The study aimed to compare effectiveness and safety of thermal ablation and hepatic resection in patients with liver metastases of gastrointestinal stromal tumors (GISTs).Method: A total of 55 patients (27 in the ablation group and 28 in the surgery group) with liver metastases were included. Overall survival (OS) and progression-free survival (PFS) were assessed with Kaplan-Meier's survival estimate curves. Univariate and multivariate regression analyses were carried out to identify potential prognostic factors.Results: The median OS was 102.0 months in the ablation group and 117.0 months in the surgery group (p = .875). The 1-, 3- and 5-year OS rates were 100%, 88.9% and 74.1% in the ablation group and 92.8%, 82.1% and 78.6% in the surgery group, respectively. The 1-, 3- and 5-year PFS rates were 48.1%, 25.9% and 18.5% in the ablation group and 67.8%, 64.3% and 64.3% in the surgery group, respectively. Multivariate analysis showed that preoperative tyrosine kinase inhibitor (TKI) treatment (progressive disease, PD) (HR, 13.985; 95% CI, 1.791-109.187; p = .012) was the only significant independent prognostic factor for OS. Tumor number (HR, 1.318; 95% CI, 1.021-1.702; p = .034) was identified as an independent predictor for PFS in multivariate analysis. There were fewer postoperative complications (18.5% vs. 78.6%, p = .001) and shorter lengths of hospital stay (8.0 vs. 16.5 days, p = .001) in the ablation group.Conclusion: Compared with resection, thermal ablation offered comparable OS for liver metastases of GISTs. Furthermore, thermal ablation had the advantages of fewer complications and shorter lengths of hospital stay.

Risk Factors for Bile Duct Injury After Percutaneous Thermal Ablation of Malignant Liver Tumors: A Retrospective Case-Control Study.

BACKGROUND: Bile duct injury after ablation of malignant liver tumors (MLTs) was not unusual and should be avoided. However, few studies have focused on evaluating the risk factors for intrahepatic bile duct injury. AIM: To evaluate the risk factors for intrahepatic bile duct injury after ablation of MLTs and to evaluate the minimum safe distance for ablating tumors abutting bile ducts. METHODS: Sixty-five patients with intrahepatic bile duct injury after ablation of MLTs, and 65 controls were recruited. Risk factors for intrahepatic bile duct injury were analyzed. Tumor location was recorded as ≤5 mm (group A), 5-10 mm (group B), and >10 mm (group C) from the right/left main duct or segmental bile duct. RESULTS: Ascites history (P < 0.001), TACE treatment history (P = 0.025), intrahepatic bile duct dilatation before ablation (P < 0.001), and tumor location (P = 0.000) were identified as significant risk factors for intrahepatic bile duct injury. Significant differences in the risk of intrahepatic bile duct injury were found between groups B and C (P = 0.000), but not between groups A and B (P = 0.751). Ascites history (P = 0.002) and tumor location (P < 0.001) were independent predictors with the OR (95 % confidence interval) of 39.31(3.95-391.69) and 16.56 (5.87-46.71), respectively. CONCLUSIONS: Bile duct injury after ablation of MLTs was the result of local treatment-related factors combined with the patients' general condition. The minimum safe distance for ablation of tumor abutting a bile duct was 10 mm.

Comparison of contrast-enhanced ultrasound and contrast-enhanced computed tomography in evaluating the treatment response to transcatheter arterial chemoembolization of hepatocellular carcinoma using modified RECIST.

PURPOSE: We aimed to compare contrast-enhanced ultrasound (CEUS) with contrast-enhanced computed tomography (CECT) for evaluating the treatment response to transcatheter arterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Treatment responses of 130 patients who underwent TACE were evaluated by CEUS and CECT. We initially compared the abilities of CEUS and CECT to detect residual tumour, which were confirmed by histology or angiography. Then, we compared the tumour response to TACE assessed by CEUS and CECT, according to Modified Response Evaluation Criteria in Solid Tumours (mRECIST). RESULTS: The sensitivity and accuracy of detecting residual tumour by CEUS vs. CECT were 95.9 % vs. 76.2 % (p < 0.001) and 96.2 % vs. 77.7 % (p < 0.001), respectively. For target lesions, 13 patients were observed as complete response (CR) by CEUS, compared to 36 by CECT (p < 0.001). For nontarget lesions, 12 patients were observed as CR by CEUS, compared to 22 by CECT (p = 0.006). For overall response, eight patients were observed as CR by CEUS, compared to 31 by CECT (p < 0.001). CONCLUSION: The diagnostic performance of CEUS was superior to CECT for detecting residual tumour after TACE. In clinical, CEUS should be recommended as an optional procedure for assessing the tumour response to TACE. KEY POINTS: • The mRECIST are widely applied for evaluating the response of HCC. • Imaging method has been applied to assess the therapeutic response to TACE. • The diagnostic performance of CEUS was superior to CECT for residual tumours. • CEUS can be a valuable method for assessing tumour response to TACE.

Ultrasomics in liver cancer: Developing a radiomics model for differentiating intrahepatic cholangiocarcinoma from hepatocellular carcinoma using contrast-enhanced ultrasound.

BACKGROUND: Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) represent the predominant histological types of primary liver cancer, comprising over 99% of cases. Given their differing biological behaviors, prognoses, and treatment strategies, accurately differentiating between HCC and ICC is crucial for effective clinical management. Radiomics, an emerging image processing technology, can automatically extract various quantitative image features that may elude the human eye. Reports on the application of ultrasound (US)-based radiomics methods in distinguishing HCC from ICC are limited. AIM: To develop and validate an ultrasomics model to accurately differentiate between HCC and ICC. METHODS: In our retrospective study, we included a total of 280 patients who were diagnosed with ICC (n = 140) and HCC (n = 140) between 1999 and 2019. These patients were divided into training (n = 224) and testing (n = 56) groups for analysis. US images and relevant clinical characteristics were collected. We utilized the XGBoost method to extract and select radiomics features and further employed a random forest algorithm to establish ultrasomics models. We compared the diagnostic performances of these ultrasomics models with that of radiologists. RESULTS: Four distinct ultrasomics models were constructed, with the number of selected features varying between models: 13 features for the US model; 15 for the contrast-enhanced ultrasound (CEUS) model; 13 for the combined US + CEUS model; and 21 for the US + CEUS + clinical data model. The US + CEUS + clinical data model yielded the highest area under the receiver operating characteristic curve (AUC) among all models, achieving an AUC of 0.973 in the validation cohort and 0.971 in the test cohort. This performance exceeded even the most experienced radiologist (AUC = 0.964). The AUC for the US + CEUS model (training cohort AUC = 0.964, test cohort AUC = 0.955) was significantly higher than that of the US model alone (training cohort AUC = 0.822, test cohort AUC = 0.816). This finding underscored the significant benefit of incorporating CEUS information in accurately distinguishing ICC from HCC. CONCLUSION: We developed a radiomics diagnostic model based on CEUS images capable of quickly distinguishing HCC from ICC, which outperformed experienced radiologists.

Liver stiffness in hepatocellular carcinoma and chronic hepatitis patients: Hepatitis B virus infection and transaminases should be considered.

BACKGROUND: Liver condition is a crucial prognostic factor for patients with hepatocellular carcinoma (HCC), but a convenient and comprehensive method to assess liver condition is lacking. Liver stiffness (LS) measured by two-dimensional shear wave elastography may help in assessing liver fibrosis and liver condition. Chronic hepatitis B (CHB) is an important risk factor for HCC progression, but LS was found to be less reliable in assessing liver fibrosis following hepatitis viral eradication. We hypothesize that the status of hepatitis virus infection would affect the accuracy of LS in assessing the liver condition. AIM: To test the feasibility and impact factors of using LS to assess liver condition in patients with HCC and CHB. METHODS: A total of 284 patients were retrospectively recruited and classified into two groups on the basis of serum CHB virus hepatitis B virus (HBV)-DNA levels [HBV-DNA ≥ 100.00 IU/mL as Pos group (n = 200) and < 100.00 IU/mL as Neg group (n = 84)]. Correlation analyses and receiver operating characteristic analyses were conducted to evaluate the relationship between LS and liver condition. RESULTS: A significant correlation was found between LS and most of the parameters considered to have the ability to evaluate liver condition (P < 0.05). When alanine aminotransferase (ALT) concentrations were normal (≤ 40 U/L), LS was correlated with liver condition indices (P < 0.05), but the optimal cutoff of LS to identify a Child-Pugh score of 5 was higher in the Neg group (9.30 kPa) than the Pos group (7.40 kPa). When ALT levels were elevated (> 40 U/L), the correlations between LS and liver condition indices were not significant (P > 0.05). CONCLUSION: LS was significantly correlated with most liver condition indices in patients with CHB and HCC. However, these correlations varied according to differences in HBV-DNA and transaminase concentrations.

Complementary Role of CEUS and CT/MR LI-RADS for Diagnosis of Recurrent HCC.

PURPOSE: We retrospectively compared the diagnostic performance of contrast-enhanced ultrasonography (CEUS) and contrast-enhanced computer tomography-magnetic resonance imaging (CT/MRI) for recurrent hepatocellular carcinoma (HCC) after curative treatment. MATERIALS AND METHODS: After curative treatment with 421 ultrasound (US) detected lesions, 303 HCC patients underwent both CEUS and CT/MRI. Each lesion was assigned a Liver Imaging Reporting and Data System (LI-RADS) category according to CEUS and CT/MRI LI-RADS. Receiver-operating characteristic (ROC) curves were computed to determine the optimal diagnosis algorithms for CEUS, CT and MRI. The diagnostic accuracy, sensitivity, specificity, and area under the curve (AUC) were compared between CEUS and CT/MRI. RESULTS: Among the 421 lesions, 218 were diagnosed as recurrent HCC, whereas 203 lesions were diagnosed as benign. In recurrent HCC, CEUS detected more arterial hyperenhancement (APHE) and washout than CT and more APHE than MRI. CEUS yielded better diagnostic performance than CT (AUC: 0.981 vs. 0.958) (p = 0.024) comparable diagnostic performance to MRI (AUC: 0.952 vs. 0.933) (p > 0.05) when using their optimal diagnostic criteria. CEUS missed 12 recurrent HCCs, CT missed one, and MRI missed none. The detection rate of recurrent HCC on CEUS (94.8%, 218/230) was lower than that on CT/MRI (99.6%, 259/260) (p = 0.001). Lesions located on the US blind spots and visualization score C would hinder the ability of CEUS to detect recurrent HCC. CONCLUSION: CEUS demonstrated excellent diagnostic performance but an inferior detection rate for recurrent HCC. CEUS and CT/MRI played a complementary role in the detection and characterization of recurrent HCC.

Application of the CT/MRI LI-RADS Treatment Response Algorithm to Contrast-Enhanced Ultrasound: A Feasibility Study.

Purpose: The contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) treatment response algorithm (TRA) is still in development. The aim of this study was to explore whether the CT/MRI LI-RADS TRA features were applicable to CEUS in evaluating the liver locoregional therapy (LRT) response. Patients and Methods: This study was a retrospective review of a prospectively maintained database of patients with hepatocellular carcinoma undergoing ablation between July 2017 and December 2018. The standard criteria for a viable lesion were a histopathologically confirmed or typical viable appearance in the follow-up CT/MRI. Performance of the LI-RADS TRA assessing tumor viability was then compared between CEUS and CT/MRI. Inter-reader association was calculated. Results: A total of 244 patients with 389 treated observations (118 viable) were evaluated. The sensitivity and specificity of the CEUS TRA and CT/MRI LI-RADS TRA viable categories for predicting viable lesions were 55.0% (65/118) versus 56.8% (67/118) (P = 0.480) and 99.3% (269/271) versus 96.3% (261/271) (P = 0.013), respectively. The PPV of CEUS was higher than that of CT/MRI (97.0% vs 87.0%). Subgroup analysis showed that the sensitivity was low in the 1-month assessment for both CEUS (38.1%, 16/42) and CT/MR (47.6%, 20/42) and higher in the 2-6-month assessment for both CEUS (65.7%, 23/35) and CT/MR (62.9%, 22/35). Interobserver agreements were substantial for both CEUS TRA and CT/MRI LI-RADS TRA (κ, 0.74 for both). Conclusion: The CT/MRI LI-RADS TRA features were applicable to CEUS TRA for liver locoregional therapy. The CEUS TRA for liver locoregional therapy has sufficiently high specificity and PPV to diagnose the viability of lesions after ablation.

Intrahepatic cholangiocarcinoma and hepatocellular carcinoma: differential diagnosis with contrast-enhanced ultrasound.

OBJECTIVE: We assessed the usefulness of contrast-enhanced ultrasound (CEUS) in the differentiation of intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC). METHODS: The CEUS enhancement patterns of 50 ICCs were retrospectively analysed and compared with 50 HCCs. Two readers independently reviewed the baseline ultrasound (BUS) and CEUS images and the diagnostic performances were evaluated by receiver operating characteristic (ROC) analysis. Time-intensity curves (TIC) were plotted for quantification analysis. RESULTS: In the arterial phase, peripheral rim-like hyperenhancement, heterogeneous hyperenhancement, homogeneous hyperenhancement and heterogeneous hypoenhancement were found in 25, 10, 3 and 12 of the ICCs versus 2, 29, 19 and 0 of the HCCs (P < 0.001), respectively. The diagnostic performance of both readers in terms of the area under the ROC curve (0.745 vs. 0.933 for reader 1, and 0.803 vs. 0.911 for reader 2), sensitivity (28% vs. 90%, and 44% vs. 82%) and accuracy (64% vs. 90%, and 71% vs. 90%) improved significantly after CEUS (all P < 0.05). The interobserver agreement increased from kappa = 0.575 at BUS to kappa = 0.720 after CEUS. TICs demonstrated that the intensities of the peripheral and central portions of the ICCs were lower than those of HCCs (both P < 0.05). CONCLUSION: CEUS improves the diagnostic performance significantly in the differentiation between ICC and HCC.

Differential diagnosis between benign and malignant gallbladder diseases with real-time contrast-enhanced ultrasound.

The value of contrast-enhanced ultrasound (CEUS) in differential diagnosis between benign and malignant gallbladder diseases was investigated. Thirty-three patients with gallbladder carcinomas and 47 with benign gallbladder diseases underwent CEUS. The lesion enhancement time, enhancement extent, pattern, dynamic change of enhancement and the intactness of gallbladder wall were evaluated. In the early phase at CEUS, hyper-, iso-, hypo-, and non-enhancement were found in 84.8% (28/33), 9.1% (3/33), 6.1% (2/33), and 0% (0/33) of gallbladder carcinomas, and 70.3% (33/47), 17.0% (8/47), 2.1% (1/47), and 10.6% (5/47) of benign diseases (p > 0.05). Hyper-enhancement or iso-enhancement in the early phase and then fading out to hypo-enhancement within 35 s after contrast agent administration was found in 90.9% (30/33) of carcinomas and 17.0% (8/47) of benign lesions (p < 0.001). Destruction of the gallbladder wall intactness was absent in benign diseases, whereas it was present in 28 (84.8%) of the 33 carcinomas (p < 0.001). Destruction of gallbladder wall intactness on CEUS yielded the highest capability in differential diagnosis, with sensitivity, specificity, and Youden's index of 84.8% (28/33), 100% (47/47), and 0.85, respectively. Conventional US made correct original diagnoses in 55 (68.8%) patients, whereas CEUS in 77 (96.3%). Thus, CEUS is useful in differential diagnosis between malignant and benign gallbladder diseases.

Multiple-Electrode Switching-Based Radiofrequency Ablation vs. Conventional Radiofrequency Ablation for Single Early-Stage Hepatocellular Carcinoma Ranging From 2 to 5 Cm.

Purpose: To retrospectively compare the treatment outcome of multiple-electrode switching-based radiofrequency ablation (switching RFA) and the conventional RFA for early-stage hepatocellular carcinoma (HCC). Methods: A total of 122 patients with single early-stage HCC ranging from 2.1 to 5.0 cm received ultrasonography-guided percutaneous RFA as the first-line treatment. Seventy-one patients underwent switching RFA, and 51 underwent conventional RFA. Tumor response, major complication, local tumor progression (LTP), and overall survival (OS) were compared between the two groups. Log-rank tests and Cox regression models were used for univariate and multivariate analyses to identify predictors of LTP and OS. Results: The rate of initial local complete response rates were 100% (71/71) in the switching RFA group and 98.0% (50/51) in the conventional RFA group (P > 0.05). No major complication occurred in the switching RFA group, whereas two in the conventional RFA group. After a median follow-up period of 45.9 months (range, 9.8-60.0 months), the rates of LTP in the switching RFA and conventional RFA groups were 19.7% (14/71) and 41.2% (21/51), respectively. The cumulative LTP rates at 1, 3, and 5 years were 11.3, 20.5, and 20.5% for switching RFA and 17.6, 38.7, and 46.7% for conventional RFA, respectively (p < 0.001). Switching RFA was an independent factor associated with a lower LTP rate (p = 0.022). Five-year OS rates were 75.8% after switching RFA vs. 66.2% after conventional RFA (p = 0.363). Extrahepatic recurrence was a significant prognostic factor for OS in multivariable analysis. Conclusion: Compared with conventional RFA, switching RFA provides a high local tumor control for single early-stage HCC. An ongoing randomized trial might help to clarify the role of this approach for the treatment of HCC.

Diagnostic performance of contrast-enhanced ultrasound for complex cystic focal liver lesions: blinded reader study.

The study was aimed at evaluating the diagnostic performance of contrast-enhanced ultrasound (CEUS) in characterizing complex cystic focal liver lesions (FLLs). Sixty-seven complex cystic FLLs in 65 patients were examined with conventional ultrasound (US) and real-time CEUS. The US and CEUS images were reviewed by a resident radiologist and a staff radiologist independently. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic performance, and the interobserver agreement was analysed. The results showed that complete non-enhancement throughout three phases of CEUS or sustained enhancement in the portal and late phases were exhibited in most benign lesions. Conversely, hypo-enhancement in the late phase was seen in all malignancies. After ROC analysis, the areas (Az) under the ROC curve were 0.774 at US versus 0.922 at CEUS (P=0.047) by the resident radiologist, and 0.917 versus 0.935 (P=0.38) by the staff radiologist. A significant difference in Az between the resident and the staff radiologists was found for US (0.774 versus 0.917, P=0.044), whereas not found for CEUS (0.922 versus 0.935, P=0.42). Interobserver agreement was improved after CEUS (kappa=0.325 at US versus kappa=0.774 at CEUS). Real-time CEUS improves the capability of discrimination between benign and malignant complex cystic FLLs, especially for the resident radiologist.

Ultrasound and Contrast-Enhanced Ultrasound for Evaluation of Irreversible Electroporation Ablation: In Vivo Proof of Concept in Normal Porcine Liver.

The objective of this study was to describe the performance of ultrasound (US) and contrast-enhanced ultrasound (CEUS) within 2 h after irreversible electroporation (IRE) ablation of porcine liver. Six IRE ablations were performed on porcine liver in vivo; ultrasound assessments were performed within 2 h after IRE ablation. On US images, the ablation zone appeared as a hypo-echoic area within 10 min after the ablation, and then the echo of the ablation zone gradually increased. On CEUS images, the ablation zone appeared as a non-enhanced area within 10 min after ablation and then was gradually centripetally filled by microbubbles. A hyper-echoic rim on US images and a hyper-enhanced rim on CEUS images appeared in the periphery of the ablation zone 60 min after the ablation. Characteristic and dynamic ultrasound images of the IRE ablation zone were obtained within 2 h after IRE ablation of in vivo porcine liver.

Maximum Value Measured by 2-D Shear Wave Elastography Helps in Differentiating Malignancy from Benign Focal Liver Lesions.

The goal of the work described here was to evaluate the diagnostic efficacy of 2-D shear wave elastography (2-D SWE) in differentiating malignancy from benign focal liver lesions (FLLs). The maxima, minima, means and the standard deviations of 2-D SWE measurements, expressed in kilopascals (Emax, Emin, Emean, ESD), were obtained for 221 patients with 229 FLLs. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic performance of 2-D SWE. The Mann-Whitney U-test was used to assess inter-group differences. Emax, Emin, Emean and ESD were significantly higher in the 164 malignant lesions than in the 65 benign lesions (p < 0.001). For identification of malignant FLLs, the areas under receiver operating characteristic curves for Emax, Emin, Emean and ESD were 0.920, 0.710, 0.879 and 0.915, respectively. Emax was 96.21 ± 35.40 for 19 intrahepatic cholangiocarcinomas and 90.32 ± 54.71 for 35 liver metastatic lesions, which were significantly higher than 61.83 ± 28.87 for 103 hepatocellular carcinomas (p < 0.0001 and p = 0.0237). Emax was 38.72 ± 18.65 for 15 focal nodular hyperplasias, which was significantly higher than 20.56 ± 10.74 for 37 hemangiomas (p = 0.0009). The Emax values for adjacent liver parenchyma of hepatocellular carcinomas and intrahepatic cholangiocarcinomas were significantly higher than those for the other three lesion types (p < 0.005). In conclusion, Emax values of FLLs and adjacent liver parenchyma could help in differentiating malignant from benign FLLs.