Percutaneous US/MRI Fusion-guided Radiofrequency Ablation for Recurrent Subcentimeter Hepatocellular Carcinoma: Technical Feasibility and Therapeutic Outcomes

3D fusion is superior to 2D point-to-point contrast-enhanced US to evaluate the ablative margin after RFA for hepatocellular carcinoma

PURPOSE

To compare the efficiency of three-dimensional (3D) and two-dimensional (2D) contrast-enhanced ultrasound (CEUS)-derived techniques in evaluating the ablative margin (AM) after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).

METHODS

In total, 98 patients with 98 HCCs were enrolled. The 2D CEUS point-to-point imaging (2D CEUS-PI) was conducted by comparing the pre- and post-RFA 2D CEUS images manually, and the 3D CEUS fusion imaging (3D CEUS-FI) was conducted by fusing the pre- and post-RFA 3D CEUS images automatically. These two techniques were compared in distinguishing an adequate AM ≥ 5 mm. Risk factors for local tumor progression (LTP) after RFA were analyzed by the Kaplan-Meier method with log-rank test.

RESULTS

The mean registration time of 3D CEUS-FI and 2D CEUS-PI was 5.0 and 9.3 min, respectively (p < 0.0001). The kappa coefficient was 0.680 for agreement between 2D CEUS-PI and 3D CEUS-FI in the evaluation of AM (p < 0.0001). Tumors with AM < 5 mm by 2D CEUS-PI were all identified as AM < 5 mm by 3D CEUS-FI. Nonetheless, 16 (26%) tumors identified as AM ≥ 5 mm by 2D CEUS-PI were re-classified as AM < 5 mm by 3D CEUS-FI. During a median follow-up time of 31.2 months (range, 3.2-66.0 months), LTP was identified in 8 tumors. The estimated 1-/2-/3-year cumulative incidence of LTP was 4.4%, 8.1%, and 10.3%, respectively. Higher estimated cumulative incidence of LTP was identified in tumors with AM < 5 mm by 2D CEUS-PI (at 3-year, 27.2% vs 0%; p < 0.001), and by 3D CEUS-FI (at 3-year, 20.7% vs 0%; p = 0.004).

CONCLUSION

3D CEUS-FI excelled in the evaluation of AM when compared with 2D CEUS-PI. With equivalent efficacy in the prediction of LTP, 3D CEUS-FI was superior to 2D CEUS-PI for its automatic and time-saving procedure.

CLINICAL RELEVANCE STATEMENT

3D CEUS fusion imaging may serve as an effective tool in evaluating ablative margin and predicting local tumor progression after RFA in HCC.

KEY POINTS

• Both 2D and 3D CEUS-derived techniques could evaluate ablative margin (AM) after RFA for hepatocellular carcinoma. • 3D CEUS fusion imaging was more precise in the evaluation of AM compared to 2D CEUS point-to-point imaging, with advantages of its automatic and time-saving procedure. • An inadequate AM < 5 mm evaluated by CEUS-derived techniques was the only risk factor of LTP after RFA for hepatocellular carcinoma (p < 0.001 for 2D CEUS point-to-point imaging, and p = 0.004 for 3D CEUS fusion imaging).

Chemoembolization versus Radiotherapy for Single Hepatocellular Carcinomas of ≤3 cm Unsuitable for Image-Guided Tumor Ablation

Background/Aims

Local ablation therapy (LAT) is primarily recommended for solitary inoperable hepatocellular carcinomas (HCCs) of ≤3 cm in diameter. However, only two-thirds of uninodular small HCCs are suitable for LAT, and the second-best treatment option for managing these nodules is unclear. We aimed to compare the therapeutic outcomes of chemoembolization and radiotherapy in small HCCs unsuitable for LAT.

Methods

The study included 651 patients from a tertiary referral center who underwent planning sonography for LAT. These patients had 801 solitary HCCs of ≤3 cm in diameter and were treated with LAT, chemoembolization, or radiotherapy. Local tumor progression (LTP)-free survival and overall survival (OS) were measured according to the type of treatment of the index nodule.

Results

LAT, chemoembolization, and radiotherapy were used to treat 561, 185, and 55 nodules in 467, 148, and 36 patients, respectively. LTP-free survival was significantly shorter in patients treated with chemoembolization than for those treated with LAT (multivariate hazard ratio [HR], 2.36; 95% confidence interval [CI], 1.61 to 3.47) but not for those treated with radiotherapy (HR, 0.83; 95% CI, 0.38 to 1.83). However, OS was not affected by treatment modality. Matching and weighting analyses confirmed that radiotherapy gave comparable results to chemoembolization in terms of OS despite better LTP-free survival (HR, 2.91; 95% CI, 1.13 to 7.47 and HR, 3.07; 95% CI, 1.11 to 8.48, respectively).

Conclusions

Our data suggest that chemoembolization and radiotherapy are equally effective options for single small HCCs found to be unsuitable for LAT after sonographic planning. Betterfit indications for each procedure should be established by specifically designed studies.

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.

Abbreviated MRI for Secondary Surveillance of Recurrent Hepatocellular Carcinoma After Presumed Curative Treatment

BACKGROUND

Little is known about the performance of abbreviated MRI (AMRI) for secondary surveillance of recurrent hepatocellular carcinoma (HCC) after curative treatment.

PURPOSE

To evaluate the detection performance of AMRI for secondary surveillance of HCC after curative treatment.

STUDY TYPE

Retrospective.

POPULATION

A total of 243 patients (183 men and 60 women; median age, 65 years) who underwent secondary surveillance for HCC using gadoxetic acid-enhanced MRI after more than 2 year of disease-free period following curative treatment, including surgical resection or radiofrequency ablation (RFA).

FIELD STRENGTH/SEQUENCE

A 3.0 T/noncontrast AMRI (NC-AMRI) (T2-weighted fast spin-echo, T1-weighted gradient echo, and diffusion-weighted images), hepatobiliary phase AMRI (HBP-AMRI) (T2-weighted fast spin-echo, diffusion-weighted, and HBP images), and full-sequence MRI ASSESSMENT: Four board-certified radiologists independently reviewed NC-AMRI, HBP-AMRI, and full-sequence MRI sets of each patient for detecting recurrent HCC.

STATISTICAL TESTS

Per-lesion sensitivity, per-patient sensitivity and specificity for HCC detection at each set were compared using generalized estimating equation.

RESULTS

A total of 42 recurred HCCs were confirmed in the 39 patients. The per-lesion and per-patient sensitivities did not show significant differences among the three image sets for either reviewer (P ≥ 0.358): per-lesion sensitivity: 59.5%-83.3%, 59.5%-85.7%, and 59.5%-83.3%, and per-patient sensitivity: 53.9%-83.3%, 56.4%-85.7%, and 53.9%-83.3% for NC-AMRI, HBP-AMRI, and full-sequence MRI, respectively. Per-lesion pooled sensitivities of NC-AMRI, HBP-AMRI, and full-sequence MRI were 72.6%, 73.2%, and 73.2%, with difference of -0.6% (95% confidence interval: -6.7, 5.5) between NC-AMRI and full-sequence MRI and 0.0% (-6.1, 6.1) between HBP-AMRI and full-sequence MRI. Per-patient specificity was not significantly different among the three image sets for both reviewers (95.6%-97.1%, 95.6%-97.1%, and 97.6%-98.5% for NC-AMRI and HBP-AMRI, respectively; P ≥ 0.117).

DATA CONCLUSION

NC-AMRI and HBP-AMRI showed no significant difference in detection performance to that of full-sequence gadoxetic acid-enhanced MRI during secondary surveillance for HCC after more than 2-year disease free interval following curative treatment. Based on its good detection performance, short scan time, and lack of contrast agent-associated risks, NC-AMRI is a promising option for the secondary surveillance of HCC.

EVIDENCE LEVEL

3.

TECHNICAL EFFICACY

Stage 2.

Consensus on the tertiary prevention of primary liver cancer

To effectively prevent recurrence, improve the prognosis and increase the survival rate of primary liver cancer (PLC) patients with radical cure, the Chinese Society of Hepatology, Chinese Medical Association, invited clinical experts and methodologists to develop the Consensus on the Tertiary Prevention of Primary Liver Cancer, which was based on the clinical and scientific advances on the risk factors, histopathology, imaging finding, clinical manifestation, and prevention of recurrence of PLC. The purpose is to provide a current basis for the prevention, surveillance, early detection and diagnosis, and the effective measures of PLC recurrence.

C-Arm Computed Tomographic Image Fusion for Repetitive Transarterial Chemoembolization of Hepatocellular Carcinoma

OBJECTIVE

The aim of this study was to evaluate the potential implications of fusion imaging with C-arm computed tomography (CACT) scans for repetitive conventional transarterial chemoembolization (cTACE) for hepatocellular carcinoma.

MATERIALS AND METHODS

Fifty-six cTACE sessions were performed using fusion CACT images from September 2020 to June 2021 in a tertiary referral center, and the data were retrospectively analyzed. Fusion of unenhanced and enhanced CACT images was considered when previously accumulated iodized oil hampered the identification of local tumor progression or intrahepatic distant metastasis (indication A), when a tumor was supplied by multiple arteries with different origins from the aorta and missing tumor enhancement was suspected (indication B), or when iodized oil distribution on immediate post-cTACE CACT images needed to be precisely compared with the pre-cTACE images (indication C). Fusion image quality, initial tumor response, time to local progression (TTLP) of index tumors, and time to progression (TTP) were evaluated.

RESULTS

The fusion quality was satisfactory with a mean misregistration distance of 1.4 mm. For the 40 patients with indication A, the initial tumor responses at 3 months were nonviable, equivocal, and viable in 27 (67.5%), 4 (10.0%), and 9 (22.5%) index tumors, respectively. The median TTLP and TTP were 14.8 months and 4.5 months, respectively. For 10 patients with indication B, the median TTLP and TTP were 8.3 months and 2.6 months, respectively. Among the 6 patients with indication C, 2 patients were additionally treated at the same cTACE session after confirming incomplete iodized oil uptake on fusion imaging.

CONCLUSIONS

Fusion CACT images are useful in patients with hepatocellular carcinoma undergoing repetitive cTACE.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

KEY POINTS

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

A review of MRI (CT)/US fusion imaging in treatment of breast cancer

The ultrasound fusion imaging system is a diagnostic device developed in Japan that utilizes ultrasound and magnetic positioning/navigation. A position sensor with a probe reads spatial location information from a magnetic field generator and by synchronously displaying ultrasound images and magnetic resonance (MR)/computed tomography (CT) images in real time. Lesions that are difficult to observe via ultrasonography alone, such as non-mass enhancement, can be identified. Furthermore, lesions that are difficult to identify with ultrasound alone indicated for MRI-guided biopsy under the National Health Insurance Scheme can be identified using ultrasound fusion technology, thereby enabling tissue biopsy to be performed under ultrasound guidance. Using this ultrasound fusion technology, not only non-mass enhancement but also small lesions that are difficult to identify using ultrasound alone can be detected, thus ensuring that a more accurate preoperative imaging diagnosis is established, and leading to safer, more reassuring examinations and surgical procedures. In this paper, we outline the use of this ultrasound fusion technology and fusion techniques in the treatment of breast cancer.

Efficacy of fusion imaging for immediate post-ablation assessment of malignant liver neoplasms: A systematic review

BACKGROUND

Percutaneous thermal ablation has become the preferred therapeutic treatment option for liver cancers that cannot be resected. Since ablative zone tissue changes over time, it becomes challenging to determine therapy effectiveness over an extended period. Thus, an immediate post-procedural evaluation of the ablation zone is crucial, as it could influence the need for a second-look treatment or follow-up plan. Assessing treatment response immediately after ablation is essential to attain favorable outcomes. This study examines the efficacy of image fusion strategies immediately post-ablation in liver neoplasms to determine therapeutic response.

METHODOLOGY

A comprehensive systematic search using PRISMA methodology was conducted using EMBASE, MEDLINE (via PUBMED), and Cochrane Library Central Registry electronic databases to identify articles that assessed the immediate post-ablation response in malignant hepatic tumors with fusion imaging (FI) systems. The data were retrieved on relevant clinical characteristics, including population demographics, pre-intervention clinical history, lesion characteristics, and intervention type. For the outcome metrics, variables such as average fusion time, intervention metrics, technical success rate, ablative safety margin, supplementary ablation rate, technical efficacy rate, LTP rates, and reported complications were extracted.

RESULTS

Twenty-two studies were included for review after fulfilling the study eligibility criteria. FI's immediate technical success rate ranged from 81.3% to 100% in 17/22 studies. In 16/22 studies, the ablative safety margin was assessed immediately after ablation. Supplementary ablation was performed in 9 studies following immediate evaluation by FI. In 15/22 studies, the technical effectiveness rates during the first follow-up varied from 89.3% to 100%.

CONCLUSION

Based on the studies included, we found that FI can accurately determine the immediate therapeutic response in liver cancer ablation image fusion and could be a feasible intraprocedural tool for determining short-term post-ablation outcomes in unresectable liver neoplasms. There are some technical challenges that limit the widespread adoption of FI techniques. Large-scale randomized trials are warranted to improve on existing protocols. Future research should emphasize improving FI's technological capabilities and clinical applicability to a broader range of tumor types and ablation procedures.

Ablative strategies for recurrent hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is the fifth leading cause of cancer death worldwide and the third leading cause of all diseases worldwide. Liver transplantation, surgical resection and ablation are the three main curative treatments for HCC. Liver transplantation is the optimal treatment option for HCC, but its usage is limited by the shortage of liver sources. Surgical resection is considered the first choice for early-stage HCC, but it does not apply to patients with poor liver function. Therefore, more and more doctors choose ablation for HCC. However, intrahepatic recurrence occurs in up to 70% patients within 5 years after initial treatment. For patients with oligo recurrence after primary treatment, repeated resection and local ablation are both alternative. Only 20% patients with recurrent HCC (rHCC) indicate repeated surgical resection because of limitations in liver function, tumor location and intraperitoneal adhesions. Local ablation has become an option for the waiting period when liver transplantation is unavailable. For patients with intrahepatic recurrence after liver transplantation, local ablation can reduce the tumor burden and prepare them for liver transplantation. This review systematically describes the various ablation treatments for rHCC, including radiofrequency ablation, microwave ablation, laser ablation, high-intensity focused ultrasound ablation, cryablation, irreversible electroporation, percutaneous ethanol injection, and the combination of ablation and other treatment modalities.

Application of ablative therapy for intrahepatic recurrent hepatocellular carcinoma following hepatectomy

The post-hepatectomy recurrence rate of hepatocellular carcinoma (HCC) is persistently high, affecting the prognosis of patients. An effective therapeutic option is crucial for achieving long-term survival in patients with postoperative recurrences. Local ablative therapy has been established as a treatment option for resectable and unresectable HCCs, and it is also a feasible approach for recurrent HCC (RHCC) due to less trauma, shorter operation times, fewer complications, and faster recovery. This review focused on ablation techniques, description of potential candidates, and therapeutic and prognostic implications of ablation for guiding its application in treating intrahepatic RHCC.

Percutaneous radiofrequency ablation of hepatocellular carcinoma in a recent cohort at a tertiary cancer center: incidence and factors associated with major complications and unexpected hospitalization events

PURPOSE

This study aimed to assess the incidence of and factors associated with major complications, delayed discharge, and emergency room (ER) visits or readmission after percutaneous radiofrequency ablation (RFA) for single hepatocellular carcinoma (HCC) <3 cm in a recent cohort at a tertiary cancer center.

METHODS

A total of 188 patients with treatment-naïve single HCCs <3 cm who underwent RFA between January 2018 and April 2021 were included in the analysis. Univariable and multivariable logistic regression analyses were performed to identify the factors associated with major complications, delayed discharge, and ER visits or readmission. Local tumor progression (LTP) and overall survival were estimated using the Kaplan-Meier method and Cox proportional-hazards regression analysis.

RESULTS

Major complications occurred in 3.2% (6/188) of the patients. The longest diameter of the ablation zone was significantly larger in patients with major complications (P=0.023). Delayed discharge occurred in 5.8% (9/188) of the patients, for which albumin-bilirubin grade 3 was identified as an important determinant. No variables other than major complications were significantly associated with ER visits or readmission, which occurred in 7.0% (13/188) of the patients. Major complications, delayed discharge, and ER visits or readmission were not substantially related to the post-treatment outcomes of LTP and overall survival.

CONCLUSION

This study confirmed RFA as a highly safe procedure for single HCCs <3 cm, despite the rapidly changing RFA techniques in the most recent cohort. A large ablation zone and poor liver function were predictors of major complications and delayed discharge, respectively.

3.0-T closed MR-guided microwave ablation for HCC located under the hepatic dome: a single-center experience

PURPOSE

To analyze the clinical safety and efficacy of 3.0-T closed MR-guided microwave ablation (MWA) for the treatment of HCC located under the hepatic dome.

METHODS

From May 2018 to October 2020, 49 patients with 74 HCCs located under the hepatic dome underwent MWA using 3.0-T closed MR guidance. The technical success rate, operative time, complete ablation (CA) rate, complications, local tumor progression (LTP), tumor-free survival (TFS) and overall survival (OS) were examined. Routine blood analysis, liver/kidney function and alpha fetoprotein (AFP) and protein induced by vitamin k absent or antagonist (PIVKA) levels were compared before and 2 months after MWA.

RESULTS

All patients underwent MWA successfully, including 10 patients who underwent general anesthesia. The technical success rate was 100% without major complications. The CA rate was 95.9% (71/74) at the 2-month evaluation. The LTP rate was 2.7% during the median follow-up of 17.8 months (range: 4-43 months); the 6-, 12-, 18-month TFS rates were 97.8, 90.6, 68.1%, respectively, and the 6-, 12-, 18-month OS rates were 100, 97.6, 92.1%, respectively. There were no significant changes in routine blood tests and liver/kidney function (p > 0.05), while the AFP and PIVKA level decreased significantly at 2 months (p < 0.05).

CONCLUSION

3.0-T MR-guided MWA is safe and feasible for HCC lesions located under the hepatic dome.

Prevention of major biliary complications by fusion imaging for thermal ablation of malignant liver tumors adjacent to the bile ducts: a preliminary comparative study

PURPOSE

Ultrasound (US)-guided thermal ablation (TA) may cause major biliary complications, particularly in patients with malignant liver tumors (MLTs) adjacent to the bile ducts. Fusion imaging (FI), is postulated to reduce complication rate; however, there is a lack of clinical data to support this theory. Thus, the aim of our study was to evaluate the safety and efficacy of FI for TA of MLTs proximal to the bile ducts.

METHODS

A retrospective single-center review was conducted on a total of 289 patients with 316 MLTs adjacent to the bile ducts. The patients were divided into two groups based on whether FI was used in the ablation procedures. The choice of the FI-assisted procedure always depends on different operation periods and whether registrations will succeed. The baseline demographics and outcomes of these patients were compared. The efficacy was determined at the 1-month follow-up using contrast-enhanced computed tomography/magnetic resonance. Biliary complications and local tumor progression were subsequently followed-up every 3-6 months. The last follow-up visit was before August 30, 2019.

RESULTS

Among the included tumors, the incidence rate of major biliary complications after ablation in the FI group was 1.6%, which was significantly lower than that in the non-FI group (7.9%, p = 0.005). There was no significant difference in the efficacy rates of the techniques [99.5% (185/186) versus 98.4% (123/125), p = 0.56] or local progression rates [3.8% (7/185) versus 5.7% (7/123), p = 0.61] between the FI and non-FI groups.

CONCLUSION

FI for US-guided TA could be a noninvasive means to decrease major biliary complications. Trial registration number and date of registration: retrospectively registered.

Local diagnostic reference levels in diagnostic and therapeutic pediatric cardiology at a specialist pediatric hospital in South Africa

Introduction: Children may be at a higher risk of experiencing the detrimental effects of ionizing radiation arising from medical radiation imaging. Dose optimisation is therefore recommended to provide assurance that their exposure is as low as reasonably achievable. To this end, periodic assessment of dose levels and establishment of Local Diagnostic Reference Levels (LDRLs) in medical facilities is necessary. There is a general paucity in the literature of data pertaining to dose levels in pediatric interventional radiology. This study establishes LDRLs in diagnostic and therapeutic heart catheterization procedures at a specialist pediatric hospital in a resource constrained country.

Material and methods: Dose indicators from actual patient procedures were collected from the archive and analyzed retrospectively to determine the median, 25th, and 75th percentiles of the total Air Kerma Area Product (KAP), Cumulative Air Kerma (CAK), total Fluoroscopy Time (FT), and a total number of Cine Images (CI) of selected interventional procedures. The dose indicators were also age-stratified into five age groups defined by the International Commission on Radiation Protection publication 135. The results were compared to values available from similar studies in the literature to benchmark our dose levels. Local Dose Reference Levels were set as the 75th percentile values.

Results: For diagnostic procedures (n = 80), the 75th percentiles of KAP, CAK, FT, and CI were 4.0 Gy·cm2, 31.5 mGy, 14.3 min, and 315 frames, respectively and 3.2 Gy·cm2, 30.5 mGy, 17.5 min, and 606 frames, respectively for therapeutic procedures (n = 143).

Conclusions: The LDRLs from this study did not vary significantly from those published in the literature, suggesting that practices at our center were comparable to international norms. Regular reviews of the LDRLs must be conducted to check that the dose levels do not deviate considerably.

Impact of Extended Use of Ablation Techniques in Cirrhotic Patients with Hepatocellular Carcinoma: A Cost-Effectiveness Analysis

Simple Summary

The optimal management of non-metastatic hepatocellular carcinoma (HCC) remains debated. The association between HCC and cirrhosis influences prognosis and therapeutic choices between curative and palliative treatments. The goal of our retrospective study was to evaluate the cost-effectiveness of the extended use of ablation for the treatment of HCC with cirrhosis in an expert ablation center when compared to the non-extended use of ablation in equivalent tertiary care centers. In a propensity-score matched cohort of 532 patients with naïve HCC, the extended use of ablation led to better compliance with the Barcelona Clinic Liver Classification (BCLC) guidelines (80% vs. 67%) and was more effective and less expensive than the non-extended use of ablation strategy, particularly at an earlier stage of the disease. The shift from curative to palliative treatments was noted in a considerable percentage of patients; therefore, this needs to be redefined as the wide choice of ablation techniques and technical advances in imaging guidance increase the curative options available to treat a maximum of patients with HCC.

Abstract

Background: To evaluate the cost-effectiveness of the extended use of ablation for the treatment of hepatocellular carcinoma (HCC) with cirrhosis in an expert ablation center when compared to the non-extended use of ablation in equivalent tertiary care centers. Methods: Consecutive cirrhotic patients with non-metastatic HCC, no prior treatment, and referred to three tertiary care centers between 2012 and 2016 were retrospectively identified. The Bondy group, including all of the patients treated at Jean Verdier Hospital, where the extended use of ablation is routinely performed, was compared to the standard of care (SOC) group, including all of the patients treated at the Beaujon and Mondor Hospitals, using propensity score matching. A cost-effectiveness analysis was carried out from the perspective of French health insurance using a Markov model on a lifetime horizon. Results: 532 patients were matched. The Bondy group led to incremental discounted lifetime effects of 0.8 life-years gained (LYG) (95% confidence interval: 0.4, 1.3) and a decrease in lifetime costs of EUR 7288 (USD 8016) (95% confidence interval: EUR 5730 [USD 6303], EUR 10,620 [USD 11,682]) per patient, compared with the SOC group, resulting in a dominant mean incremental cost-effectiveness ratio (ICER). A compliance with the Barcelona Clinic Liver Classification (BCLC) guidelines for earlier stage contributed to the greater part of the ICER. Conclusion: The extended use of ablation in cirrhotic patients with HCC was more effective and less expensive than the non-extended use of the ablation strategy.

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

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

Preferred Treatment with Curative Intent for Left Lateral Segment Early Hepatocellular Carcinoma under the Era of Minimal Invasive Surgery

Background: Hepatocellular carcinoma (HCC) occurring at the left lateral segment (LLS) is relatively susceptible to treatment with curative intent in terms of tumor location. However, outcomes might vary depending on the selection of treatment modalities. This study aimed to analyze patients who had undergone curative treatment for early HCC at LLS. Methods: A retrospective analysis of 179 patients who underwent curative treatment for early HCC at LLS was performed. Patients were grouped based on treatment modalities, including radiofrequency ablation (RFA) and liver resection (LR). The long-term outcomes of the two groups were compared. Additionally, the impact of the LR approach on patient outcomes was analyzed. Results: Among these patients, 60 received RFA and 119 underwent LR as primary treatment with curative intent. During follow-up, a significantly higher incidence of HCC recurrence was observed in the RFA group (37/60, 61.7%) than in the LR group (45/119, 37.8%) (p = 0.0025). The median time of HCC recurrence was 10.8 (range: 1.1–60.9 months) and 17.6 (range: 2.4–94.8 months) months in the RFA and LR groups, respectively. In addition, multivariate analysis showed that liver cirrhosis, multiple tumors, and RFA treatment were significant risk factors for HCC recurrence. The 1-, 2-, and 5-year overall survival rates in the RFA and LR groups were 96.4%, 92.2%, and 71.5% versus 97.3%, 93.6%, and 87.7%, respectively. (p = 0.047). Moreover, outcomes related to LR were comparable between laparoscopic and conventional open methods. The 1-, 2-, and 5-year recurrence free survival rates in the laparoscopic (n = 37) and conventional open (n = 82) LR groups were 94.1%, 82.0%, and 66.9% versus 86.1%, 74.6%, and 53.1%, respectively. (p = 0.506) Conclusion: Early HCC at LLS had satisfactory outcomes after curative treatment, in which LR seems to have a superior outcome, as compared to RFA treatment. Moreover, laparoscopic LR could be considered a preferential option in the era of minimally invasive surgery.

Efficacy and Safety of Fusion Imaging in Radiofrequency Ablation of Hepatocellular Carcinoma Compared to Ultrasound: A Meta-Analysis

Background: Radiofrequency ablation (RFA), generally performed under real-time guidance of ultrasound which is safe and effective, is a common minimally invasive therapy for treating hepatocellular carcinoma. Fusion imaging (FI) is a newly developed imaging method, which integrates CT/MRI accurate imaging and matches the characteristics of real-time ultrasound imaging, thereby providing a new approach to guide tumor ablation therapy. However, the efficacy and safety of FI as opposed to ultrasound in tumor ablation remains unclear.

Objective: The present study sought to evaluate the difference in the efficacy and safety between FI and ultrasound in radiofrequency surgery for the treatment of hepatocellular carcinoma through a metaanalysis.

Materials and Methods: Searching for studies comparing the efficacy and safety of FI and ultrasound in radiofrequency of hepatocellular carcinoma in PubMed, Embase, and Cochrane Library databases for articles published until April 2021. Random or fixed effect models were used for statistical analysis. Metaanalysis and sensitivity analysis were used on the included studies.

Results: A total of six studies met predefined inclusion criteria, and were finally included in the analysis. Sensitivity and subgroup analyses, based on predetermined patient characteristics, allowed minimization of bias. In the RFA of hepatocellular carcinoma, FI decreased 1-year overall survival (OS) when compared with ultrasound. But FI was not significantly different from ultrasound in terms of technical efficiency, 1-, 2-, and 3-year local tumor progression (LTP), complications, as well as 2-year OS. Subgroup analysis, based on tumor mean diameter, showed that FI reduced the rate of 1- and 2-year LTP in patients with tumors of mean diameter ≥15 mm when compared with ultrasound. Moreover, operative complications could be reduced in patients with tumor mean diameter <15 mm using FI, compared with ultrasound.

Conclusion: Overall, these results showed that FI may have some effects on improving efficacy and safety of thermal ablation in HCC patients, relative to ultrasound. However, it may be a more effective method for managing large lesions, as well as those that are difficult to ablate. Further large-scale and well-designed randomized controlled trials are needed to validate these findings.

Review of clinical tumor ablation advance in Asia

Tumor ablation has been widely applied in Asia, accounting for 44.65% of clinical studies worldwide. We reviewed 5853 clinical studies to provide insight on the advance of tumor ablation in Asia chronologically and geographically among different techniques and organs. Since 1998, tumor ablation application has dramatically evolved in Asia. All kinds of ablation techniques, including percutaneous ethanol injection (PEI), radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation (LA), cryoablation (CA), high-intensity focused ultrasound (HIFU), and irreversible electroporation (IRE), have been applied, with the first application of PEI and the most popular application of RFA. Twenty-five countries and one district in Asia have applied tumor ablation in various organs, including liver, lung, uterus, thyroid, kidney, pancreas, bone, prostate, breast, adrenal gland, lymph node parathyroid, esophagus, etc. Due to the high incidence of tumors as well as advanced economy and technology, East Asia accounted for 93.87% of studies, led by China (45.00%), Japan (32.72%), South Korea (12.10%), and Taiwan (4.03%). With the enrichment of evidence from large-scale multicenter and randomized control studies, China and South Korea have issued several guidelines on tumor ablation for liver, lung, and thyroid, which provided recommendations for global standardization of tumor ablation techniques. Therefore, Asia has made active contribution to global tumor ablation therapy.KeypointsKey point 1: Asia accounted for 44.65% of clinical studies worldwide on tumor ablation.Key point 2: Twenty-five countries and one district in Asia have used tumor ablation in various organs, and East Asia accounted for 93.87% of studies, led by China (45.00%), Japan (32.72%), South Korea (12.10%), and Taiwan (4.03%).Key point 3: China and South Korea have issued several guidelines on tumor ablation for liver, lung, and thyroid, which provided recommendations for global standardization of tumor ablation techniques.

Operator Evaluation of Ultrasound Fusion Imaging Usefulness in the Percutaneous Ablation of Hepatic Malignancies: A Prospective Study

The purpose of the work described here was to evaluate the use of ultrasound fusion imaging (US-FI) in percutaneous ablation of hepatic malignancies with respect to its global usefulness, improvement of conspicuity, confidence increment, needle route changes, and time savings. Thirty-four hepatic tumors (28 hepatocellular carcinomas, 6 metastases) were prospectively ablated in 16 consecutive patients (64 ± 11 y, 75% males), first simulating B-mode-only planning and then synchronizing computed tomography/magnetic resonance images with US and proceeding to needle insertion and tumor ablation under US-FI guidance. Surveys were administered to the operators to evaluate their perception of US-FI advantages. First treatment and local recurrence were also compared. US-FI was judged useful in 91% of cases and more useful when the tumor was not conspicuous in B-mode (p < 0.001), in particular for ablation of local recurrences (p = 0.021). Forty-one percent of tumors were undetectable at B-mode evaluation, and 93% of them were completely ablated under US-FI guidance. The confidence of the operator was highly increased by US-FI in 68% of cases. In 71% of cases, the radiologist saved time using US-FI, especially in treatment of local recurrences (p = 0.024). In conclusion, US-FI significantly increases the detection of target tumors, improves the confidence of the operator and is a time-saving method, especially in the treatment of local recurrences.

Magnetic resonance-guided thermal ablation for small liver malignant tumor located on segment II or IVa abutting the heart: a retrospective cohort study

OBJECTIVE

This study aimed to evaluate the clinical safety and efficacy magnetic resonance (MR)-guided percutaneous thermal ablation for the treatment of small liver malignant tumors of segment II and IVa (≤3.0 cm) abutting the heart.

METHOD

The enrollment of 24 patients with 25 malignant liver lesions located on the II or IVa segment abutting the heart who underwent MRI-guided thermal ablation between August 2010 and February 2020 were retrospectively analyzed. Follow-up MRI was performed to evaluate the curative effect. Local tumor progression-free survival and overall survival rates were also calculated.

RESULTS

The procedures including radiofrequency ablation (RFA) for 15 patients and microwave ablation (MWA) for 9 patients were successfully accomplished (technical success rate of 100%) without major complications. The mean duration time was 78.4 ± 29.4 min (40-140 min), and mean follow-up time was 31.5 ± 22.2 months (6-92 months). The technical efficacy was 100% following one ablation session with MRI assessment after one month. Local tumor progression was observed in one patient with a metastatic lesion located in segment II at 18 months follow-up. The progression-free survival time was 20.1 ± 16.9 months (median: 15 months). The 1-, 3-, and 5-year local tumor progression-free survival rates of this patient were 100%, 94.7%, and 94.7%, respectively. With regards to all the patients, the 1-, 3-, and 5-year estimated overall survival rates were 91.7%, 80.6%, and 50.1%, respectively.

CONCLUSION

MR-guided thermal ablation is safe and effective for the treatment of small liver malignant tumors located on the II or IVa segment abutting the heart.

Combined ablation-chemotherapy versus chemotherapy alone for pancreatic cancer with liver metastasis: a propensity score matching study

Objectives: To retrospectively assess the efficacy of combined ablation-chemotherapy in comparison to that of chemotherapy alone in patients with liver metastasized pancreatic ductal adenocarcinoma (lmPDAC).Methods: In total 104 patients with hepatic oligo metastasized PDAC were identified; among them, 74 patients underwent combined thermal ablation-chemotherapy, and 30 patients underwent chemotherapy alone. Through propensity score matching, 1:1 matching of the combined ablation-chemotherapy group and chemotherapy group was achieved. The primary endpoint of this study was overall survival (OS). Clinical and tumor-related factors affecting OS were also analyzed through univariate and multivariate analyses using the Cox risk model.Results: For patients treated with combined ablation-chemotherapy, the median OS was 10.77 months, while it was 5.77 months for patients treated with chemotherapy alone (P = 0.011). The survival benefit for patients treated with combined ablation-chemotherapy was still preserved in the matched cohort, with a median OS of 8.17 months compared to 5.77 months in the chemotherapy group. Univariate and multivariate analyses in the matched population also showed treatment with combined ablation-chemotherapy was an independent prognostic factor (P < 0.05).Conclusions: For patients with liver metastases from pancreatic cancer, the combined use of thermal ablation and systemic chemotherapy offers a chance for a better survival outcome.

A new model based on gamma-glutamyl transpeptidase to platelet ratio (GPR) predicts prognostic outcome after curative resection of solitary hepatocellular carcinoma

BACKGROUND

This study intends to explore the potential clinical value of gamma-glutamyl transpeptidase to platelet ratio (GPR) and the new multi-factor scoring model for recurrence and prognosis prediction in solitary HCC patients who received radical resection.

METHODS

This study retrospectively analyzed 295 HCC patients after curative resection. According to the Receiver Operating Characteristic (ROC) curve, the optimal cut-off value of GPR for predicting prognosis of HCC after resection was determined. The Kaplan Meier method and Cox regression analysis were performed to assess the important potential factors in the prognosis of HCC and determine the independent risk factors. Assign a value to each independent risk factor and establish a new scoring model. Then, using GPR and the new scoring model to evaluate overall survival (OS) and postoperative recurrence probability.

RESULTS

When GPR's cut-off value was selected as 0.30, its predictive efficiency for postoperative prognosis was more favorable than those of other cut-off values (0.76, 0.84 and 0.94). GPR, tumor size, microvascular invasion and neutrophil to lymphocyte ratio (NLR) were identified as independent prognostic predictors. Using these variables, a novel prognostic scoring model was devised and established to identify different levels of risk: high, intermediate and low risk groups. We found that patients with high GPR level and of high risk group would have a poorer OS and a higher recurrence rate after radical resection.

CONCLUSIONS

GPR may serve as a promising predictor for postoperative prognosis and recurrence probability of HCC, and the new prognostic scoring model may be available for postoperative management among HCC patients.

Utility of Real-time CT/MRI-US Automatic Fusion System Based on Vascular Matching in Percutaneous Radiofrequency Ablation for Hepatocellular Carcinomas: A Prospective Study

PURPOSE

To prospectively evaluate the technical success rate of real-time computed tomography/magnetic resonance imaging and ultrasound (CT/MRI-US) automatic fusion system and the long-term therapeutic efficacy of radiofrequency ablation (RFA) guided by automatic fusion in hepatocellular carcinoma (HCC) patients.

MATERIALS AND METHODS

139 patients with 151 HCCs were prospectively enrolled for RFA guided by an automatic CT/MRI-US fusion system (PercuNav system, Philips, the Netherlands). Automatic fusion imaging, based on vascular segmentation and registration, was performed by sonographic sweeping at the intercostal plane. The fusion quality, tumor localization confidence and technical feasibility were recorded before and after fusion using a scoring system. Technical success rate of the RFA procedure and local tumor progression (LTP) were assessed during follow-up. Analysis of technical success and LTP was performed using generalized estimating equations and Cox proportional hazard regression analysis.

RESULTS

The success rate of the fusion system was 82.7% (115/139) per patient. The mean sonographic scan time for fusion was 154.4 ± 108.4 s. In patients with successful fusion, the score indicating tumor localization confidence (2.2 ± 0.8 vs. 2.7 ± 0.9) and technical feasibility (2.6 ± 0.8 vs. 3.4 ± 0.7) increased after fusion (p < 0.001). The technical success rate of the RFA procedure was 96.8% (120/124) per tumor in patients with successful fusion, including poorly localized tumors. LTP rates were 8.6%, 12.2% and 15.2% at 1, 2 and 3 years.

CONCLUSION

The CT/MRI-US automatic fusion system showed a high success rate for image registration and facilitated better feasibility and a high technical success rate of RFA in HCCs, even with poor localization on US.

LEVEL OF EVIDENCE

Level 3b, Nonrandomized prospective study.

Comparison of procedure-related complications between percutaneous cryoablation and radiofrequency ablation for treating periductal hepatocellular carcinoma

PURPOSE

This study aimed to evaluate the incidence and severity of biliary complications after treating periductal hepatocellular carcinomas (HCCs) using either cryoablation (CA) or radiofrequency ablation (RFA) and assess independent risk factors for biliary complications after treatment.

MATERIALS AND METHODS

Between July 2008 and August 2018, 949 patients with treatment-naïve HCCs underwent either RFA or CA in our institution. Of these, patients with multiple HCCs, tumors equal to or larger than 3 cm or smaller than 1 cm, and tumors with non-periductal locations were excluded. Finally, 31 patients and 25 patients were included in the RFA group and the CA group, respectively. The incidence and severity of biliary complications were compared between the RFA and CA groups. The risk factors for biliary complications were assessed using univariable and multivariable logistic regression analyses using the following variables: age, sex, tumor size, Child-Pugh score, tumor location (peripheral duct versus central duct), ablation method (RFA versus CA), the number of applicators, ablation time, and ablation volume.

RESULTS

The incidence and severity of biliary complications were significantly higher in the RFA group than in the CA group (p = 0.007 and p = 0.002, respectively). In univariable and multivariable analyses, the ablation method was an independent risk factor for biliary complications (p = 0.004 and 0.013, respectively).

CONCLUSIONS

The incidence and severity of biliary complications after treating HCCs abutting the bile duct are lower in CA than RFA, demonstrating that CA is safer than RFA for ablating small periductal HCCs.

Intraprocedurally EOB-MRI/US fusion imaging focusing on hepatobiliary phase findings can help to reduce the recurrence of hepatocellular carcinoma after radiofrequency ablation

BACKGROUND & AIMS

To explore the ability of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging (EOB-MRI)/ultrasound (US) fusion imaging (FI) to improve the prognosis of radiofrequency ablation (RFA) by ablating the characteristic findings of hepatocellular carcinoma (HCC) in hepatobiliary phase (HBP) imaging.

METHODS

We retrospectively recruited 115 solitary HCC lesions with size of (15.9 ± 4.6) mm. They were all treated by RFA and preoperative EOB-MRI. According to the modalities guiding RFA performance, the lesions were grouped into contrast enhanced US (CEUS)/US guidance group and EOB-MRI/US FI guidance group. For the latter group, the ablation scope was set to cover the HBP findings (peritumoral hypointensity and irregular protruding margin). The presence of HBP findings, the modalities guided RFA, the recurrence rate were observed.

RESULTS

After an average follow-up of 377 days, local tumor progression (LTP) and intrahepatic distant recurrence (IDR) were 14.8% and 38.4%, respectively. The lesions having HBP findings exhibited a higher recurrence rate (73.7%) than the lesions without HBP findings (42.9%) (p = 0.002) and a low overall recurrence-free curve using the Kaplan-Meier method (p = 0.038). Using EOB-MRI/US FI as guidance, there was no difference in the recurrence rate between the groups with and without HBP findings (p = 0.799). In lesions with HBP findings, RFA guided by EOB-MRI/US FI (53.8%) produced a lower recurrence rate than CEUS/US (84.0%) (p = 0.045).

CONCLUSIONS

The intraprocedurally application of EOB-MRI/US FI to determine ablation scope according to HBP findings is feasible and beneficial for prognosis of RFA.

Percutaneous radiofrequency ablation for hepatic metastasis of colorectal cancer: assessment of tumor visibility and the feasibility of the procedure with planning ultrasonography

Purpose

The aim of this study was to assess the incidence and causes of percutaneous radiofrequency ablation (RFA) infeasibility in cases of metastatic colorectal cancer and to evaluate factors affecting the invisibility of the tumor on planning ultrasonography (US).

Methods

This study screened 386 patients who underwent planning US using fusion imaging and/or contrast-enhanced US for percutaneous RFA for suspected metastatic colorectal cancer between January 2013 and December 2020, from whom 136 patients with a single hepatic metastasis from colorectal cancer measuring <3 cm were included. The factors related to the infeasibility of percutaneous RFA were investigated. Univariate and multivariate analyses were performed to assess the factors associated with tumor invisibility on planning US.

Results

Among the 136 patients, percutaneous RFA was considered infeasible in 24.3% (33/136) due to a high risk of the heat-sink effect caused by the abutment of a large vessel (n=12), an inconspicuous tumor on planning US (n=11), a high risk of collateral thermal damage to an adjacent organ (n=8), and the absence of a safe electrode path (n=2). In univariate and multivariate analyses, tumor size was a statistically significant factor affecting invisibility on planning US (P=0.003 and P=0.018, respectively).

Conclusion

Percutaneous RFA was infeasible in approximately one-fourth of patients with metastatic colorectal cancer. The reason for the infeasibility was mainly an unfavorable tumor location and invisibility on planning US. Small tumor size was the sole significant factor affecting the invisibility of hepatic metastases on planning US.

Challenges Facing Percutaneous Ablation in the Treatment of Hepatocellular Carcinoma: Extension of Ablation Criteria

As an emerging minimally invasive treatment method, percutaneous ablation is more and more widely used in the treatment of liver tumors. It has been recommended by guidelines for diagnosis and treatment of hepatocellular carcinoma (HCC) as a curative treatment alongside surgical resection and liver transplantation. In recent years, with the continuous advancement and innovation of percutaneous ablation technologies, their clinical efficacy and safety have been significantly improved, which has led to the expanded application of percutaneous ablation in the treatment of HCC—more and more patients who were previously considered unsuitable for ablation therapies are now being treated with percutaneous ablation. Obviously, percutaneous ablation can reduce the risk of treatment changes from curative strategies to palliative strategies. Based on clinical practice experience, this review enumerates the advantages and disadvantages of different ablative modalities and summarizes the existing combinations of ablation techniques, thus will help clinicians choose the most appropriate ablative modality for each patient and will provide scientific guidance for improving prognosis and making evidence-based treatment decisions. In addition, we point out the challenges and future prospects of the ablation therapies, thereby providing direction for future research.

Feasibility of 3D US/CEUS-US/CEUS fusion imaging-based ablation planning in liver tumors: a retrospective study

PURPOSE

To assess the feasibility of ablation planning based on fusion imaging of three-dimensional ultrasound/contrast-enhanced ultrasound (3D US/CEUS) with real-time US/CEUS for liver tumor thermal ablation.

MATERIALS AND METHODS

Between January 2017 and December 2018, 85 hepatic tumors from 82 patients who underwent percutaneous ablation were included. First, intraprocedural 3D US/CEUS imaging was performed for ablation planning. Then, fusion imaging of 3D US/CEUS with real-time US/CEUS was used to guide the implementation of the plan, immediately evaluate the technical success and indicate the need for supplemental ablation. In addition, contrast-enhanced CT/MR imaging was performed 1 month after the procedure to evaluate the presence of residual tumors, and follow-up scans were repeated every 3 months.

RESULTS

The average liver tumor diameter was 28 ± 9 mm (range, 10-55 mm). 3D US/CEUS-based planning was successfully conducted in all 85 tumors with a 100% technical success rate of planning. The immediate evaluation by 3D CEUS/US-CEUS fusion imaging showed a 100% technical success rate of ablation. The 1-month CT/MR scans found a residual tumor in one intrahepatic cholangiocarcinoma patient; the technique efficacy rate was 98.8%. The median follow-up period was 21.5 months (IQR: 4-36 months). During the follow-up period, the local tumor progression rate was 5.9% (5/84), and no major procedure-related complications occurred.

CONCLUSIONS

Ablation planning based on 3D US/CEUS-US/CEUS fusion imaging is feasible for liver tumors.

The semi-erect position for better visualization of subphrenic hepatocellular carcinoma during ultrasonography examinations

PURPOSE

This study investigated which body position is more useful for visualizing subphrenic hepatocellular carcinomas (HCCs) during ultrasonography (US) examinations.

METHODS

This prospective study was approved by the institutional review board and written informed consent was obtained from all patients. Twenty consecutive patients with a single subphrenic HCC (treatment-naïve, 1 to 3 cm) underwent a US examination for planning radiofrequency ablation. The examinations were done by one of three radiologists and the patients were examined in four different body positions-supine, right posterior oblique (RPO), left lateral decubitus (LLD), and semi-erect-by being positioned on a tilted table. The visibility of the index tumor was prospectively assessed using a 4-point scale. Needle insertion was considered to be technically feasible if the visibility score was lower than 2. The visibility score and technical feasibility were compared using the Wilcoxon signed rank test and the McNemar test, respectively, for pairwise comparisons between different body positions.

RESULTS

The visibility score was significantly lower in the semi-erect position (median, 2; interquartile range, 1 to 2.75) than in the supine (3, 2 to 4), RPO (3, 2 to 4), and LLD (4, 3.25 to 4) positions (P=0.007, P=0.005, and P=0.001, respectively). The technical feasibility of needle insertion was also significantly higher in the semi-erect position (75%, 15/20) than in the supine (45%, 9/45), RPO (35%, 7/20), and LLD (20%, 4/20) positions (P=0.031, P=0.021, and P=0.001, respectively).

CONCLUSION

The semi-erect position is more useful for the visualization of subphrenic HCCs than the supine, RPO, or LLD positions.

Intra-Procedural CT/MR-Ultrasound Fusion Imaging Helps to Improve Outcomes of Thermal Ablation for Hepatocellular Carcinoma: Results in 502 Nodules

PURPOSE

 The aim was to assess the value of intra-procedural CT/MR-ultrasound (CT/MR-US) fusion imaging in the management of thermal ablation for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

 This retrospective study was approved by the institutional review board. From May 2010 to October 2016, 543 HCC nodules in 440 patients (387 men and 53 women; age range: 25-84 years) that met the Milan Criteria were treated by percutaneous thermal ablation using intra-procedural CT/MR-US fusion imaging. The HCC nodules were divided into subgroups and compared (≤ 3 cm and > 3 cm, or high-risk and low-risk location, or inconspicuous and conspicuous, respectively). Technique efficacy and major complication were calculated. Cumulative local tumor progression (LTP), tumor-free and overall survival rates were estimated with the Kaplan-Meier method.

RESULTS

 CT/MR-US fusion imaging was successfully registered in 419 patients with 502 nodules. The technique efficacy rate of thermal ablation was 99.4 %. The major complication rate was 1.9 %. The cumulative LTP rates were 3.2 %, 5.6 % and 7.2 % at 1, 3, and 5 years, respectively. There were no significant differences for the comparisons of cumulative LTP rates between different subgroups (P = 0.541, 0.314, 0.329). The cumulative tumor-free survival rates were 74.8 %, 54.0 % and 37.5 % at 1, 3, and 5 years, respectively. The cumulative overall survival rates were 97.8 %, 87.1 % and 81.7 % at 1, 3, and 5 years, respectively.

CONCLUSION

 Intra-procedural CT/MR-ultrasound fusion imaging is a useful technique for percutaneous liver thermal ablation. It could help to achieve satisfying survival outcomes for HCC patients who meet the Milan Criteria.

Risk factors and clinical outcomes of extrahepatic recurrence in patients with post-hepatectomy recurrent hepatocellular carcinoma

BACKGROUND

Extrahepatic recurrence remains a major obstacle to an improved prognosis in patients with hepatocellular carcinoma (HCC) undergoing hepatectomy.

METHODS

From January 2001 to December 2014, we screened 1330 consecutive patients who underwent curative hepatectomy for HCC. Patients who experienced recurrence were enrolled in this study and divided into an extrahepatic recurrence (EHR) group and a pure intrahepatic recurrence (IHR) group. Clinical data and follow-up results were retrospectively collected and analysed.

RESULTS

A total of 556 patients were enrolled (EHR, 52; IHR, 504). In the EHR group, the lung was the most common site of extrahepatic recurrence (53.8%), among which 67.3% had associated intrahepatic lesions. Background Hepatitis B (HR 0.282; 95% CI 0.106-0.752; P = 0.011), tumour size ≥10 cm at initial diagnosis (HR 2.679; 95% CI 1.283-5.596; P = 0.009) and blood transfusion during initial surgery (HR 2.218; 95% CI 1.132-4.346; P = 0.020) were predictive of EHR. A multidisciplinary team treated recurrent HCC. After a median follow-up period of 46 months (range, 24-192 months), the 1-, 3- and 5-year overall survival rates in the EHR group were 60.7%, 8.9% and 0%, respectively, after recurrence, and 78.8%, 30.2% and 8.9%, respectively, after initial surgery, which were much lower than those in the IHR group.

CONCLUSION

Tumour size ≥10 cm and blood transfusion during initial surgery were predictive of extrahepatic recurrence in patients with post-hepatectomy recurrent HCC. Treatment options were limited, and long-term survival was unsatisfactory.

Image Guidance in Ablation for Hepatocellular Carcinoma: Contrast-Enhanced Ultrasound and Fusion Imaging

The ultrasound (US) imaging technology, including contrast-enhanced US (CEUS) and fusion imaging, has experienced radical improvement, and advancement in technology thus overcoming the problem of poor conspicuous hepatocellular carcinoma (HCC). On CEUS, the presence or absence of enhancement distinguishes the viable portion from the ablative necrotic portion. Using volume data of computed tomography (CT) or magnetic resonance imaging (MRI), fusion imaging enhances the three-dimensional relationship between the liver vasculature and HCC. Therefore, CT/MR-US fusion imaging provides synchronous images of CT/MRI with real-time US, and US-US fusion imaging provides synchronous US images before and after ablation. Moreover, US-US overlay fusion can visualize the ablative margin because it focuses the tumor image onto the ablation zone. Consequently, CEUS and fusion imaging are helpful to identify HCC with little conspicuity, and with more confidence, we can perform ablation therapy. CEUS/fusion imaging guidance has improved the clinical effectiveness of ablation therapy in patients with poor conspicuous HCCs. Therefore; this manuscript reviews the status of CEUS/fusion imaging guidance in ablation therapy of poor conspicuous HCC.

Improving Ablation Safety for Hepatocellular Carcinoma Proximal to the Hilar Bile Ducts by Ultrasound-MR Fusion Imaging: A Preliminary Comparative Study

Aim

To explore whether ablation safety could be improved by ultrasound (US)-magnetic resonance (MR) fusion imaging for hepatocellular carcinoma (HCC) proximal to the hilar bile ducts (HBDs) through a preliminary comparative study.

Methods

Between January 2014 and June 2019, 18 HCC nodules proximal to the HBDs were included in a US-MR fusion imaging-assisted radiofrequency ablation (RFA) group (study group), while 13 HCC nodules in a similar location were included as a control group. For the study group, the tumor and adjacent bile ducts were outlined on preprocedural MR images. Procedural ablation planning was conducted to assess the feasibility of ablating the tumors while avoiding biliary injury. Such tumors were then ablated under US-MR fusion imaging guidance. The control group nodules were ablated under conventional ultrasound guidance. Baseline characteristics and outcomes were compared between the groups.

Results

After preprocedural assessment, 14 of 18 patients with tumors that were feasible to ablate underwent US-MR fusion imaging-assisted RFA. No biliary complications were observed in these 14 patients; the complication rate was significantly lower in the study group than in the control group (30.8%, 4/13) (P = 0.041). There was no significant difference in the technique efficacy rates [92.9% (13/14) versus 100% (13/13), P = 1] or local progression rates [7.1% (1/14) versus 7.7% (1/13), P = 1] between the study and control groups.

Conclusions

US-MR fusion imaging may be a non-invasive means for assisting RFA of HCC nodules proximal to the HBDs and ensuring ablation safety.

Proton beam radiotherapy vs. radiofrequency ablation for recurrent hepatocellular carcinoma: A randomized phase III trial

BACKGROUND & AIMS

Proton beam radiotherapy (PBT) has recently been applied to treat hepatocellular carcinoma (HCC); however, there is no randomized controlled trial-based evidence on its safety and efficacy. We compared the outcomes of PBT and radiofrequency ablation (RFA) in patients with recurrent/residual HCC (rHCC) in a phase III non-inferiority trial.

METHODS

Patients with rHCC (size <3 cm, number ≤2) were randomly assigned to receive PBT or RFA according to Child-Pugh score and tumor stage. After randomization, if the assigned treatment was technically infeasible, crossover was allowed. The primary endpoint was 2-year local progression-free survival (LPFS), with a non-inferiority margin of 15% in the per-protocol (PP) population; a complementary analysis was performed in the intention-to-treat (ITT) population (NCT01963429).

RESULTS

The ITT population comprised 144 patients receiving either PBT (n = 72) or RFA (n = 72). Six patients switched from the PBT arm to the RFA arm and 19 patients switched from the RFA arm to the PBT arm. In the PP population, the 2-year LPFS rate with PBT (n = 80) vs. RFA (n = 56) was 94.8% vs. 83.9%, a difference of 10.9 percentage points (90% CI 1.8-20.0; p <0.001); in the ITT population, the 2-year LPFS rate with PBT vs. RFA was 92.8% vs. 83.2%, a difference of 9.6 percentage points (90% CI 0.7-18.4; p <0.001), meeting the criteria for non-inferiority. The 3- and 4-year LPFS rates for PBT were also non-inferior to those for RFA. The most common adverse events were radiation pneumonitis (32.5%) and decreased leukocyte counts (23.8%) for PBT and increased alanine aminotransferase levels (96.4%) and abdominal pain (30.4%) for RFA. No Grade 4 adverse events or mortality were noted.

CONCLUSIONS

PBT showed LPFS values that were non-inferior to those for RFA; in addition, PBT was tolerable and safe. CLINICAL TRIAL NUMBER: #NCT01963429 (ClinicalTrials.gov).

LAY SUMMARY

Radiofrequency ablation is the standard of care for patients with small hepatocellular carcinoma in whom surgery is not feasible. This study is the first phase III randomized controlled trial to evaluate the clinical outcomes of proton beam radiotherapy vs. radiofrequency ablation in patients with recurrent small HCC. Our findings show that this new technique is not inferior and can be applied safely in patients with small recurrent hepatocellular carcinoma.

Can Immediately Treating Subcentimeter Hepatocellular Carcinoma Improve the Survival of Patients?

Background

With the development of imaging technology, an increasing number of subcentimeter hepatocellular carcinoma (HCC) has been detected. How to manage these lesions remains controversial and lacks evidence. We aimed to explore whether timely treating subcentimeter HCC is necessary considering the risks of false-positives and treatment failure.

Methods

In this retrospective study, we reviewed HCC patients treated with hepatectomy or ablation in our institution. Then, we enrolled 439 HCC patients with solitary lesion measuring up to 2 cm from November 1, 2009 to June 30, 2019. The baseline and clinical characteristics of these patients were collected. The patients were classified into primary and recurrent groups. The Kaplan–Meier method with Log-rank test was performed to compare the overall survival (OS) and recurrence-free survival (RFS) between patients with subcentimeter HCC and those with HCC measuring 1–2 cm. Univariate and multivariate analyses were adopted to identify prognostic factors for survival.

Results

The OS and RFS did not differ significantly between patients with subcentimeter HCC and those with HCC measuring 1–2 cm in the primary group (p = 0.12 and 0.75). Similar results were found in the recurrent group. In multivariate analysis, the albumin-bilirubin (ALBI) grade and serum alpha fetoprotein (AFP) level were significantly associated with OS and RFS in the primary group. The serum AFP level was the only factor that correlated with OS and RFS in the recurrent group.

Conclusion

Routine screening for subcentimeter HCC is feasible. Considering uncertain diagnosis and treatment difficulties, it is more considerable to follow patients until lesions are larger than 1 cm and then provide curative treatments.

Virtual navigation-guided radiofrequency ablation for recurrent hepatocellular carcinoma invisible on ultrasound after hepatic resection

BACKGROUND

No reports are available on the technical efficiency and therapeutic response of virtual navigation (VN)-guided radiofrequency ablation (RFA) for patients with recurrent hepatocellular carcinoma (HCC) after hepatic resection. The aim of this study was to investigate the overall technical performance and outcome of VN-guided RFA in recurrent HCC patients. In addition, a nomogram model was developed to predict the factors influencing the overall survival (OS).

METHODS

This was a prospective study on 76 recurrent HCC patients who underwent VN-guided RFA between June 2015 and February 2018. The technical feasibility, success, and efficiency, OS, local tumor progression, and complications were evaluated. A multivariate Cox regression analysis was conducted to predict the significant factors, and a nomogram including independent predictive factors was subsequently plotted to predict OS.

RESULTS

The technical feasibility, success, and efficiency rates of VN-guided RFA were 86.4%, 94.7%, and 97.4%, respectively. The cumulative OS rates at 1-, 2-, and 3-year were 88.1%, 79.7%, and 71.0%, respectively. The cumulative local tumor progression rates at 1-, 2-, and 3-year were 5.5%, 8.7%, and 14.0%, respectively. In addition, the minor and major complication rates were 5.3% and 3.9%, respectively. No intervention-related deaths occurred during the follow-up period. The C-index of the OS nomogram in this study was 0.737.

CONCLUSIONS

VN-guided RFA is an effective therapeutic option in recurrent HCC patients and improves the long-term outcomes especially for the lesions that cannot be detected in the two-dimensional ultrasound. Besides, the nomogram may be a useful supporting tool in predicting OS to estimate the individual survival probability, optimize treatment options, and facilitate decision-making.

Percutaneous radiofrequency ablation for small hepatocellular carcinoma in hepatic dome under MR-guidance: clinical safety and efficacy

Purpose: To evaluate the clinical safety and efficacy of percutaneous radiofrequency ablation (RFA) using multitined expandable electrodes under magnetic resonance imaging (MRI) guidance in the treatment of small hepatocellular carcinomas (HCCs) in the hepatic dome.Materials and methods: The data of 49 patients with 50 HCC lesions in the hepatic dome who underwent MRI-guided RFA from April 2010 to January 2018 were retrospectively analyzed. Planning, targeting, and controlling were performed under MR-guidance during the procedure. The complications after RFA were observed. Follow-up MRI was performed to evaluate the curative effect. The local progression-free survival, recurrence-free survival, and overall survival rates were calculated using the Kaplan-Meier survival curve.Results: The procedures were successfully accomplished in all patients without major complications. The mean follow-up time was 36.9 ± 25.8 months (range, 3-99 months). Technical success was 100% after one RFA session with MRI assessment after 1 month. Local tumor progression was observed in one patient (2%) with the lesion located in the hepatic dome at 4 months on a subsequent follow-up MRI. The progression-free survival time was 25.0 ± 22.7 months (median, 17.0 months). The 1-,3-, and 5-year local tumor progression-free survival rates were all 98.0%. The 1-,3-, and 5-year recurrence-free survival rates were 68.1%, 39.9%, and 28.5%, respectively, and the estimated overall survival rates were 93.7%, 76.3%, and 54.3%, respectively.Conclusion: Planning, targeting, and controlling of RFA were well supported by MRI with acceptable time. MRI-guided RFA for small HCCs in the hepatic dome is safe and effective with fewer RF sessions.

Subcentimeter hepatocellular carcinoma in treatment-naïve patients: noninvasive diagnostic criteria and tumor staging on gadoxetic acid-enhanced MRI

OBJECTIVE

It is controversial to adopt non-invasive diagnostic criteria of hepatocellular carcinoma (HCC) in subcentimeter lesions. This study was aimed to define the optimal noninvasive diagnostic criteria of subcentimeter HCC and to evaluate the effect on tumor staging.

METHODS

We included 110 treatment-naïve patients at risk of HCC and eligible for curative treatment who had subcentimeter lesions (n = 136) on gadoxetic acid-enhanced magnetic resonance imaging (MRI) performed between January 2013 and December 2013. Modified diagnostic criteria for subcentimeter HCC were developed using logistic regression analysis. Accuracies of MR staging with and without using the modified criteria were compared by generalized estimating equation test using pathologic staging as reference standards. Subgroup analysis was performed for patients with co-existing HCC ≥ 1 cm (co-HCC).

RESULTS

The modified criteria (presence of co-HCC, arterial phase hyperenhancement, and hypointensity on transitional phase [TP]) showed 61.5% (95% CI, 41.6-78.2) of sensitivity and 98.2% (95% CI, 93.0-99.5) of specificity. Including subcentimeter HCCs improved the accuracy of MR staging from 84.5 to 94.5% (p = 0.001). Fifty percent of subcentimeter lesions found in patients with co-HCCs were HCC, whereas 5.9% of them without co-HCCs were HCC (p = 0.001). In the subgroup with co-HCCs, the accuracy of MR staging with subcentimeter HCCs was improved from 69.0% to 92.8% (p = 0.001).

CONCLUSIONS

Including subcentimeter HCCs based on the modified diagnostic criteria (co-existing HCC ≥ 1 cm, arterial phase hyperenhancement, and hypointensity on TP) improved MR staging accuracy.

KEY POINTS

• Fifty percent of non-benign appearing subcentimeter lesions found in patients with co-HCCs were HCC, whereas 5.9% of them without co-HCCs were HCC (p = 0.001). • Including subcentimeter HCCs improved the accuracy of MR staging from 84.5 to 94.5% (p = 0.001).

Prognostic significance of controlling nutritional status score-based nomogram for hepatocellular carcinoma within Milan criteria after radiofrequency ablation

Background

Radiofrequency ablation (RFA) is a curative therapy for hepatocellular carcinoma (HCC) within Milan criteria. This study was conducted to evaluate the association between controlling nutritional status (CONUT) score and oncological outcomes in HCC patients within Milan criteria after RFA. Nomograms were constructed for the prediction of prognosis.

Methods

The study included 403 HCC patients within Milan criteria who underwent RFA at National Cancer Center and the First Hospital of Shanxi Medical University from January 2010 to December 2014. Oncological outcomes included disease-free survival (DFS) and overall survival (OS). The clinical variables were assessed by univariate and multivariate Cox regression analyses. C-index, time-dependent receiver operating characteristic (t-ROC) curve (t-AUC) and calibration plots were used to evaluate discrimination and calibration of the nomograms.

Results

Patients were divided into CONUT ≤4 and ≥5 groups. The common prognostic factors affecting DFS and OS were number of lesions, tumor differentiation, and CONUT score. Age and total bilirubin (TBIL) were prognostic factors for OS only. Both DFS and OS rates in CONUT ≤4 group were significantly higher than those in CONUT ≥5 group (P=0.033, P<0.001). Two well-discriminated and calibrated nomograms were constructed to predict the probability of 1-, 2-, and 3-year DFS and 1-, 2-, 3-, 5-year OS with C-indexes of 0.798 and 0.757, respectively.

Conclusions

CONUT score is an independent prognostic factor for HCC after RFA treatment and a reliable indicator for nutritional interventions. Higher CONUT scores were associated with poor oncological outcomes. Nomograms based on CONUT score could efficiently predict DFS and OS for HCC patients within Milan criteria after RFA.

SN, Kulkarni S, Shetty NS, Gupta A, Gupta S. Indian Society of Vascular and Interventional Radiology Expert Consensus Statements for Ablation in Hepatocellular Carcinoma: Part I

Locoregional therapies play an important role in the management of hepatocellular carcinoma (HCC). Percutaneous ablation is one of the most commonly employed nonsurgical methods for treating very early and early HCC. For small HCCs, ablation is potentially curative and competes with surgical resection. The widespread availability and the spectrum of ablative techniques mandate uniform approach among interventional radiologists. Thus, it is desirable to have a consensus regarding various aspects of liver ablation. This article represents a consensus document of the experts from the Indian Society of Vascular and Interventional Radiology involved in the care of patients with HCC. The statements are presented in two parts.

Recurrence After Curative Resection of Hepatitis B Virus-Related Hepatocellular Carcinoma: Diagnostic Algorithms on Gadoxetic Acid-Enhanced Magnetic Resonance Imaging

Small recurrent hepatocellular carcinoma (HCC) can show atypical imaging patterns, and a specific diagnostic algorithm for HCC is lacking. This study aimed to better characterize postoperative recurrent HCCs <20 mm in size with gadoxetic acid-enhanced magnetic resonance imaging (MRI). We evaluated 373 newly developed nodules after hepatectomy in 204 HCC patients with chronic hepatitis B virus infection. The diagnostic performance of Liver Imaging Reporting and Data System (LI-RADS) version 2018 was calculated with gadoxetic acid-enhanced MRI to characterize recurrent HCC. Modified diagnostic algorithms were proposed by combining significant imaging biomarkers related to subcentimeter and 10-19 mm recurrence, and the algorithms were then compared with the LI-RADS system. A total of 256 recurrent HCCs (108 recurrent HCCs <10 mm in size; 148 recurrent HCCs 10-19 mm in size) were confirmed via histology or follow-up imaging. Nonrim arterial phase hyperenhancement (APHE) and 3 LI-RADS ancillary features (AFs; hepatobiliary phase hypointensity, mild-moderate T₂ hyperintensity, and restricted diffusion) were significantly related to recurrent HCCs <20 mm in size according to a multivariate analysis. For subcentimeter recurrence, combining at least 2 of the 3 AFs only achieved better specificity (sensitivity, 83.3%; specificity, 87.7%) than the LR-4 category (sensitivity, 88.9%, P = 0.21; specificity, 70.8%, P = 0.006). For 10-19 mm recurrences, combining nonrim APHE and at least 1 of the 3 AFs achieved only a significantly enhanced sensitivity of 85.1% but a lower specificity of 86.5% compared with the LR-5 category (sensitivity: 63.5%, P < 0.001; specificity: 94.2%, P = 0.13). In conclusion, the diagnostic algorithms for subcentimeter and 10-19 mm recurrent HCCs should be stratified. Combining at least 2 AFs demonstrated comparable sensitivity with significantly enhanced specificity compared with the LR-4 category for characterizing subcentimeter recurrence.

Using the Controlling Nutritional Status (CONUT) Score for Evaluating Patients with Early-Stage Hepatocellular Carcinoma After Radiofrequency Ablation: A Two-Center Retrospective Study

PURPOSE

To estimate the prognostic significance of the controlling nutritional status (CONUT) in patients with BCLC stage A hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA).

MATERIALS AND METHODS

From January 2013 to December 2016, 325 patients with BCLC stage A HCC who underwent RFA at the National Cancer Center and First Hospital of Shanxi Medical University were retrospectively studied. The patients were divided into low (≤ 4) and high (≥ 5) CONUT scores for assessment of overall survival (OS) and recurrence-free survival (RFS). Several covariates, including age, sex, the diameter and number of lesions, lesion differentiation, Child-Pugh class, hepatitis B virus infection, along with blood levels of AFP, AST, ALT, γ-GT, and TBIL, were assessed using univariate and multivariate analyses.

RESULTS

The mortality rate was 17.49% (46/263) and 35.48% (22/62) in the low and high CONUT groups, respectively, with the difference being statistically significant (P = 0.033). In addition, disease recurrence was significantly higher in the high CONUT group at 70.97%, as compared to the low CONUT group at 43.35% (P = 0.041). The predictive factors were used to build the nomogram to estimate 1-, 3- and 5-year OS and RFS rates.

CONCLUSIONS

CONUT scores were found to be associated with the prognosis of patients with early-stage HCC who underwent RFA. Higher CONUT scores were associated with poor survival outcomes.

A closer look to the new frontier of artificial intelligence in the percutaneous treatment of primary lesions of the liver

The purpose of thermal ablation is induction of tumor death by means of localized hyperthermia resulting in irreversible cellular damage. Ablative therapies are well-recognized treatment modalities for HCC lesions and are considered standard of care for HCC nodules < 3 cm in diameter in patients not suitable for surgery. Effective lesion treatment rely on complete target volume ablation. Technical limitations are represented by large (> 3 cm) or multicentric nodules as well as complex nodule location and poor lesion conspicuity. Artificial Intelligence (AI) is a general term referred to computational algorithms that can analyze data and perform complex tasks otherwise prerogative of Human Intelligence. AI has a variety of application in percutaneous ablation procedures such as Navigational software, Fusion Imaging, and robot-assisted ablation tools. Those instruments represent relative innovations in the field of Interventional Oncology and promising strategies to overcome actual limitations of ablative therapy in order to increase feasibility and technical results. This work aims to review the principal application of Artificial Intelligence in the percutaneous ablation of primary lesions of the liver with special focus on how AI can impact in the treatment of HCC especially on potential advantages on the drawbacks of the conventional technique.

The AFSUMB Consensus Statements and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound using Sonazoid

The first edition of the guidelines for the use of ultrasound contrast agents was published in 2004, dealing with liver applications. The second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some nonliver applications. The third edition of the contrast-enhanced ultrasound (CEUS) guidelines was the joint World Federation for Ultrasound in Medicine and Biology-European Federation of Societies for Ultrasound in Medicine and Biology (WFUMB-EFSUMB) venture in conjunction with other regional US societies such as Asian Federation of Societies for Ultrasound in Medicine and Biology, resulting in a simultaneous duplicate on liver CEUS in the official journals of both WFUMB and EFSUMB in 2013. However, no guidelines were described mainly for Sonazoid due to limited clinical experience only in Japan and Korea. The new proposed consensus statements and recommendations provide general advice on the use of Sonazoid and are intended to create standard protocols for the use and administration of Sonazoid in hepatic and pancreatobiliary applications in Asian patients and to improve patient management.

The AFSUMB Consensus Statements and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound using Sonazoid

The first edition of the guidelines for the use of ultrasound contrast agents was published in 2004, dealing with liver applications. The second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some nonliver applications. The third edition of the contrast-enhanced ultrasound (CEUS) guidelines was the joint World Federation for Ultrasound in Medicine and Biology-European Federation of Societies for Ultrasound in Medicine and Biology (WFUMB-EFSUMB) venture in conjunction with other regional US societies such as Asian Federation of Societies for Ultrasound in Medicine and Biology, resulting in a simultaneous duplicate on liver CEUS in the official journals of both WFUMB and EFSUMB in 2013. However, no guidelines were described mainly for Sonazoid due to limited clinical experience only in Japan and Korea. The new proposed consensus statements and recommendations provide general advice on the use of Sonazoid and are intended to create standard protocols for the use and administration of Sonazoid in hepatic and pancreatobiliary applications in Asian patients and to improve patient management.