Radiofrequency Ablation For Hepatocellular Carcinoma Research Articles

The arterial tumor enhancement pattern on contrast-enhanced computed tomography is associated with primary cancer death after radiofrequency ablation for small hepatocellular carcinoma.

Critical recurrences after radiofrequency ablation for hepatocellular carcinoma (HCC), such as intrahepatic metastases or dissemination, and extrahepatic metastases or seeding, which are difficult to treat radically, almost certainly lead to primary cancer death. The present study aimed to clarify whether the arterial tumor enhancement pattern on contrast-enhanced computed tomography (CECT) is associated with critical recurrence and cancer death after RFA for small HCC. Between April 2001 and September 2011, 226 patients with initial small hypervascular HCC (≤3 cm in diameter and ≤3 tumors) were treated by RFA. Arterial tumor enhancement patterns on CECT before RFA were categorized by whether non-enhanced areas were included inside the tumor stain. The heterogeneous enhancement group included 44 patients, and the homogeneous enhancement group included 182 patients. The cumulative 5-year critical recurrence rates of the heterogeneous and homogeneous enhancement groups were 42 and 22% (p = 0.005), respectively. Univariate analysis for factors related to critical recurrence showed significant differences in sex, arterial enhancement pattern, and response to antiviral therapy. These factors were independent on multivariate analysis. The cumulative 5-year primary cancer death rates of the heterogeneous and homogeneous enhancement groups were 29 and 13% (p = 0.002), respectively. Univariate analysis for factors related to primary cancer death showed significant differences in arterial enhancement pattern and response to antiviral therapy. These factors were independent on multivariate analysis. Arterial heterogeneous tumor enhancement on CECT is associated with critical recurrence and cancer death after RFA for small HCC.

A Patient-Based Nomogram for Predicting Overall Survival after Radiofrequency Ablation for Hepatocellular Carcinoma

PurposeTo develop a prognostic nomogram based on specific patient and tumor factors capable of estimating individual survival outcomes after radiofrequency (RF) ablation as a primary therapy for hepatocellular carcinoma (HCC). Materials and MethodsThis retrospective study included 893 patients who were initially treated with curative RF ablation for HCC; patients were temporally divided into derivation (n = 607) and validation (n = 286) cohorts. A multivariate Cox proportional hazards model for overall survival was developed and validated. The discriminatory accuracy of the model was compared with the preexisting Cancer of the Liver Italian Program (CLIP) system and the Tokyo score previously proposed for percutaneous therapy for HCC by analyzing receiver operating characteristic (ROC) curves. ResultsA nomogram was generated for 3-year survival, incorporating largest tumor diameter and number of tumors, serum albumin and creatinine, platelet count, prothrombin time, and serum α-fetoprotein on a logarithmic scale. It had good calibration and discrimination abilities with a C-index of 0.74. The validation results also showed that the nomogram performed well in terms of goodness-of-fit and discrimination (C-index, 0.72). Analysis of ROC curves in the validation cohort indicated that the model had better predictive power than CLIP and Tokyo scores (C-indexes, 0.54 and 0.66, respectively). ConclusionsThis prognostic tool quantifying per-patient expected survival after RF ablation can be used in daily clinical decision making with regard to patients with HCC deemed suitable for radical ablation and is probably more reliable than existing guidelines.

Value of pretreatment MRI determined parameters for predicting outcome after radio-frequency ablation of hepatocellular carcinoma

Methods Thirty-seven patients with HCC treated by RFA were evaluated. Lesion number, size and segmental location, T2-weighted (w), arterial, portal-venous and venous contrast-phase, b600 diffusion-w imaging (DWI) and delayed phase contrast-enhanced imaging pattern were assessed at MRI. The separate imaging patterns as well as pretreatment clinical variables were correlated with outcome (disease free survival longer or shorter than 1 year) using a chi-square test with multiple variables and Mann-Whitney U test respectively. Pretreatment clinical variables and imaging parameters were correlated with Keratin 19 and microvascular invasion status at the biopsy during RFA.

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간세포암종의 고주파 열치료술

간세포암종의 고주파 열치료술

Radiofrequency Ablation for Hepatocellular Carcinoma: Enhanced Ablative Responses Utilizing Adjuvant NaCl Pretreatments1

Radiofrequency Ablation for Hepatocellular Carcinoma: Enhanced Ablative Responses Utilizing Adjuvant NaCl Pretreatments1

Clinical usefulness of the ablative margin assessed by magnetic resonance imaging with Gd-EOB-DTPA for radiofrequency ablation of hepatocellular carcinoma

The aim of this study was to investigate the feasibility of ablative margin (AM) grading by magnetic resonance imaging (MRI) with Gd-EOB-DTPA administered prior to radiofrequency ablation (RFA), and to identify factors for achieving a sufficient AM and predictors for local tumor progression. A total of 124 hepatocellular carcinomas (HCCs) were treated by RFA after Gd-EOB-DTPA administration. MRI and enhanced CT were performed within seven hours and one month after RFA. The AM assessment was categorized using three grades: AM (+), low-intensity area with continuous high-intensity rim; AM zero, low-intensity area with discontinuous high-intensity rim; and AM (-), low-intensity area extends beyond the high-intensity rim. Patients were followed and local tumor progression was observed. AM (+), AM zero, AM (-), and indeterminate were found in 34, 33, 26, and 31 nodules, respectively. The overall agreement rate between MRI and enhanced CT for the diagnosis of AM was 56.8%. The κ coefficient was 0.326 (p<0.001), indicating moderate agreement. Multivariate logistic regression analysis showed that a significant factor for the achievement of AM (+) on MRI was no contiguous vessels. The cumulative local tumor progression rates (0% at 1, 2, and 3 years) in 33 AM (+) nodules were significantly lower than those (3.6%, 11.5%, and 18.3% at 1, 2, and 3 years respectively) in 32 AM zero nodules. A multivariate Cox proportional hazards model identified tumor size as an independent predictor for local tumor progression. Gd-EOB-DTPA-MRI enabled an early assessment of RFA effectiveness in the majority ofHCC nodules. Local tumor progression was not detected in AM (+) nodules during the follow-up.

Radiofrequency Ablation for Hepatocellular Carcinoma: Utility of Conventional Ultrasound and Contrast-Enhanced Ultrasound in Guiding and Assessing Early Therapeutic Response and Short-Term Follow-Up Results

The purpose of this study was to assess the efficacy of conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) in guiding and assessing early therapeutic response to radiofrequency (RF) ablation for hepatocellular carcinomas (HCCs; up to 3 lesions, each ≤3 cm in diameter) and to report the short-term follow-up results. Between September 2011 and January 2013, 63 patients with 78 HCCs (≤3 cm) underwent conventional US- and CEUS-guided percutaneous RF ablation. CEUS was repeated after 20–30 min to assess therapeutic response, and local efficacy was further confirmed by contrast-enhanced magnetic resonance imaging (MRI) 1 mo after tumor ablation. Patients were followed periodically to look for local tumor or disease progression. Survival probability was estimated with the Kaplan–Meier method. Complete ablation was achieved for 76 (97.4%) of 78 HCCs in one (n = 73) or two (n = 3) sessions. No major complications were observed in any patient. The overall concordance in assessment of therapeutic efficacy of RF ablation between CEUS and MRI was 97.4% (76/78 tumors). The concordance test gave a value of κ = 0.74 (p < 0.001), indicating that CEUS had a high diagnostic agreement with MRI. During a mean follow-up of 20 mo, the local tumor progression rate was 5.3% (4/76 tumors). The 1-, 1.5- and 2-y cumulative survival rates were 98.4%, 96.1% and 92.6%, respectively. Although CEUS has some intrinsic limitations, the combined use of conventional US and CEUS provides a safe and efficient tool to guide RF ablation for HCCs 3 cm or smaller, with encouraging results in terms of survival rate and minimal complications. Moreover, the immediate post-procedural CEUS can be a reliable alternative to contrast-enhanced MRI for assessing the early therapeutic response to RF ablation.

Added value of diffusion weighted MRI in evaluation of treatment response: post radiofrequency ablation for hepatocellular carcinoma

ObjectiveTo evaluate the feasibility of DWI and the corresponding ADC values to detect local tumor progression (LTP) after radiofrequency ablation for hepatocellular carcinoma. Materials and methods139 MR examinations were done for 51 HCC patients post-RFA. Pre and postgadolinium enhanced images as well as DW sequences were performed. ADC values of ablation zones and liver parenchyma were assessed. ADC values of ablation zones and adjacent signal alterations identified in DWI were analyzed. ResultsLTP was detected in 12 patients (23.5%) and 16 lesions (21.9%). The mean ADC value of ablated zones differed significantly from that of normal liver parenchyma. No obvious changes were detected in the ADC values of the ablated zones over time. ROIs covering the whole ablation zone showed no significant ADC value difference regarding the presence or absence of LTP. DWI showed 53 hyperintense areas in the periphery of the ablated zones, and the corresponding ADC values were significantly lower in patients with LTP than in patients without LTP. ConclusionDWI is a feasible follow-up tool for postablation liver contributing in detection of LTP. ADC based evaluation of signal alterations in the periphery of the ablation zone may be helpful in differentiation between LTP and post treatment tissue changes.

Local Recurrence after Radiofrequency Ablation of Hepatocellular Carcinoma: Treatment Choice and Outcome

Background/aimsRadiofrequency ablation (RFA) has been proven effective for treating small hepatocellular carcinoma (HCC) nodules. However, post-RFA local recurrence is a major factor limiting prognosis. Up to now, there is no consensus on a standardized treatment strategy for these local recurrences. The aim of this study is to evaluate the outcomes of salvage treatments for RFA-related local recurrence. MethodsFrom May 2008 to June 2013, a total of 112 patients with HCC were detected with local recurrence after RFA. Among them, 94 patients received sequential treatments in our hospital, including salvage resection (SR) (n = 24), salvage liver transplantation (n = 2), repeated RFA (n = 62), and transarterial chemoembolization (TACE) (n = 6). We evaluated the treatment outcomes of patients by salvage surgery (SS), RFA, and TACE. ResultsThe median follow-up time was 32 months. After treatment, local recurrence was eradicated in 82 of 94 patients (87.2 %). The complete response (CR) rate in the RFA group was 90.3 % (56/62), while it was 100 % (26/26) in the SS group (P = 0.175) and 0 % (0/6) in the TACE group. When analysis confined to patients with CR, the 1- and 3-year disease-free survival (DFS) rates were 57.7 and 20.2 % in the SS group, and 41.7 and 28.6 % in the RFA group, respectively (P = 0.640). The 1- and 3-year overall survival (OS) rates were 93.3 and 69.1 % in the SS group, and 78.6 and 57.5 % in the RFA group, respectively (P = 0.251). ConclusionRepeated RFA is the first treatment choice for patients with post-RFA local recurrence. SS should be considered when RFA failed or is inapplicable.

Automated Quantification of Tumor Viability in a Rabbit Liver Tumor Model after Chemoembolization Using Infrared Imaging

The rabbit VX2 tumor is a fast-growing carcinoma model commonly used to study new therapeutic devices, such as catheter-based therapies for patients with inoperable hepatocellular carcinoma. The evaluation of tumor viability after such locoregional therapies is essential to directing hepatocellular carcinoma management. We used infrared microspectroscopy for the automatic characterization and quantification of the VX2 liver tumor viability after drug-eluting beads transarterial chemoembolization (DEB-TACE). The protocol consisted of K-means clustering followed by principal component analysis (PCA) and linear discriminant analysis (LDA). The K-means clustering was used to classify the spectra from the infrared images of control or treated tumors and to build a database of many tissue spectra. On the basis of this reference library, the PCA-LDA analysis was used to build a predictive model to identify and quantify automatically tumor viability on unknown tissue sections. For the DEB group, the LDA model determined that the surface of tumor necrosis represented 91.6% ± 8.9% (control group: 33.1% ± 19.6%; Mann-Whitney P = 0.0004) and the viable tumor 2.6% ± 4% (control group: 62.2% ± 15.2%; Mann-Whitney P = 0.0004). Tissue quantification measurements correlated well with tumor necrosis (r = 0.827, P < 0.0001) and viable tumor (r = 0.840, P < 0.0001). Infrared imaging and PCA-LDA analysis could be helpful for easily assessing tumor viability.

A measure to assess the ablative margin using 3D-CT image fusion after radiofrequency ablation of hepatocellular carcinoma

ObjectivesTo examine the feasibility of three-dimensional computed tomography (3D-CT) image fusion in facilitating assessment of the ablative margin (AM) after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). MethodsThis study involved 75 patients with solitary HCC who underwent RFA. The AM was evaluated using 3D-CT image fusion. All cases were categorized into two groups based on the extent of the AM: in Group A, sufficient AM was obtained, which was greater than or equal to 5 mm; in Group B, the lesion was also ablated successfully, but a 5 mm AM was not obtained. Results3D-CT Image Fusion was performed on 36 and 39 patients in Group A and Group B, respectively. The 1, 3, 5 year RFS was 87.6%, 63.2%, 50.6% for Group A, and 77.2%, 51.5%, 35.6% for Group B, respectively (P = 0.042); the corresponding OS was 94.3%, 73.8%, 64.6%, and 86.2%, 60.5%, 47.6%, respectively (P = 0.046). Multivariate analysis showed that the AM (P = 0.048, HR = 2.15, 95% CI 1.01–4.60) and Pre-NLR were independent prognostic factors for PFS. Conclusions3D-CT image fusion is a feasible and useful method to evaluate the AM after RFA of HCC.

P0384 : Assessment of treatment response by sequential serum metabolomic profiling after percutaneous radiofrequency ablation of hepatocellular carcinoma

P0384 : Assessment of treatment response by sequential serum metabolomic profiling after percutaneous radiofrequency ablation of hepatocellular carcinoma

Sa1861 Post-Ablation Safety Margin of Radiofrequency Ablation of Hepatocellular Carcinoma: Precise Assessment With a Three Dimensionalreconstruction Technique

cell lines FRH, TFK-1and EGI were examined for basal expression of VEGF, VEGFR1, and VEGFR2 by western blotting (WB). The cells were treated with recombinant human VEGF (rhVEGF), and VEGFR phosphorylation was examined by WB, and cell proliferation was evaluated by BrdU incorpation assay. Cells were then treated with 0, 60, or 120 nM of apatinib for 24 hour, and were assayed for VEGFR signaling and cell proliferation. Finally, FRH cells were inoculated into nude mice for further evaluation for apatinib treatment efficacy in vivo. Results: All three EBDC cell lines expressed VEGF and phosphorylated (p) VEGF receptor 1 (pVEGFR1) and 2 (pVEGFR2). By protein fractionalization, we found that VEGFR1 and VEGFR2 were both present on membrane of these three cells. The rhVEGF promoted phosphorylation of VEGFR1 and VEGFR2 at 30 min (FRH and EGI) or 15 min after treatment. The rhVEGF increased cell proliferation (+16.8%, +13.4% and +20.5% for FRH, TFK and EGI respectively) after 24 hr of treatment, which was prevented by preincubation with VEGFR1 or VEGFR2 neutralizing antibody. Apatinib treatment inhibited the phosphorylation of VEGFR1 and VEGFR2 and cell proliferation in all three cell lines in a dose-dependent fashion. Finally, the apatinib-treated FRH xenograft tumors displayed a substantial delayed growth after one week-treatment. The averages of final tumor volumes were significantly different between the vehicle and apatinib-treated groups after 4 weeks of treatment (P<0.05). Conclusion: VEGF directly activated VEGF receptors on EBDC cells and promoted cancer cell proliferation; apatinib inhibited VEGF signaling and suppressed cell proliferation in vitro and delayed xenograft tumor growth in vivo. These findings support a potential role for apatinib in the treatment of extrahepatic bile duct cancers.

Sa1871 Local Recurrences and Complications After Percutaneous Radiofrequency Ablation of Hepatocellular Carcinoma: Analysis Focused on Tumor Locations

Background: Palliation for inoperable malignant distal biliary strictures can be achieved with metallic and plastic biliary stents. There have been recent retrospective studies and randomized controlled trials that evaluated the mortality and morbidity in patients with metal versus plastic stents. This is a meta-analysis to pool the evidence for survival benefit and morbidity in metallic versus plastic stents in patients with malignant distal biliary strictures. Aim: Compare survival benefit and morbidity in patients with distal biliary strictures managed with metallic stents versus plastic stents. Method: Study Selection Criteria: Studies using metallic and plastic stents for palliation in patients with malignant distal biliary stricture / obstruction. Data collection & extraction: Articles were searched in Medline, Pubmed, Ovid journals, CINAH, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane Central Register of Controlled Trials & Database of Systematic Reviews. Two reviewers independently searched and extracted data. Any differences were resolved by mutual agreement. Statistical Method: Pooled proportions were calculated using both Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity among studies was tested using Cochran's Q test based upon inverse variance weights. Results: Initial search identified 1376 reference articles, of which 91 were selected and reviewed. 10 studies (N=892) for metallic and plastic stents which met the inclusion criteria were included in this analysis. Pooled analysis by fixed effects showed an overall survival/ time to death in metallic stent group to be 157.3 days (95% CI = 148.9 to 165.6) compared to 120.6 days (95% CI = 114.3 to 126.9) in plastic stent group. Metal stents had a pooled complication rate of 3.83 % (95% CI = 3.52 to 4.14) compared to 2.17 % (95% CI = 1.91 to 2.42) for plastic stents. The pooled effects estimated by fixed and random effect models were similar. The p for chisquared heterogeneity for all the pooled accuracy estimates was > 0.10. Conclusions: In our meta-analysis of patients with malignant distal biliary strictures managed with palliative stenting, metallic stents might be associated with longer overall survival period compared to plastic stents.Metallic stenting seems to havemarginally higher percentage of complications when compared to plastic stenting.

Aggressive Intrasegmental Recurrence of Hepatocellular Carcinoma after Radiofrequency Ablation: Risk Factors and Clinical Significance.

To evaluate the frequency, risk factors, and clinical significance of aggressive intrasegmental recurrence (AIR) found after radiofrequency (RF) ablation for hepatocellular carcinoma (HCC). Institutional review board approval was obtained for this retrospective study. Between March 2005 and December 2010, 539 patients (414 men, 125 women; mean age, 57.91 years; age range, 30-82 years) underwent ultrasonography-guided percutaneous RF ablation as a first-line treatment for a single HCC classified as Barcelona Clinic Liver Cancer (BCLC) stage 0 or A. AIR of HCC was defined as (a) initial tumor recurrence with disease-free status at least 6 months after initial RF ablation and (b) the simultaneous development of multiple nodular (at least three) or infiltrative tumor recurrence in the treated segment. Patients were stratified into two groups: those with AIR (n = 20) and those without AIR (n = 519) during follow-up. Risk factors for AIR were assessed with logistic regression analysis, and risk factors for long-term overall survival were assessed with time-dependent Cox proportional hazard models. In a median follow-up period of 49 months (range, 6-95 months), AIR was observed in 3.7% of the patients (20 of 539 patients), with the frequency increasing to 15% in the subgroup with periportal HCC (11 of 72 patients). AIRs manifested as either multiple nodular type (n = 14, BCLC stage A or B) or diffusely infiltrative type with tumor thrombus formation (n = 6, BCLC stage C). At multivariate analysis, periportal tumor location and younger patient age were significant risk factors for AIR. The presence of AIR during the follow-up period has a significant effect on the overall survival rate (hazard ratio = 5.72, P = .002). The overall frequency of AIR after RF ablation for HCC was low, with periportal location and patient age showing a significant relationship to the development of AIR. The occurrence of AIR had an adverse effect on overall survival rate.

Use of transient elastography to predict de novo recurrence after radiofrequency ablation for hepatocellular carcinoma.

Background/purposeLiver stiffness (LS) measurement using transient elastography can accurately assess the degree of liver fibrosis, which is associated with the risk of the development of hepatocellular carcinoma (HCC). We investigated whether LS values could predict HCC de novo recurrence after radiofrequency ablation (RFA).MethodsThis retrospective, multicenter study analyzed 111 patients with HCC who underwent RFA and LS measurement using transient elastography between May 2005 and April 2011. All patients were followed until March 2013 to monitor for HCC recurrence.ResultsThis study included 76 men and 35 women with a mean age of 62.4 years, and the mean LS value was 21.2 kPa. During the follow-up period (median 22.4 months), 47 (42.3%) patients experienced HCC de novo recurrence, and 18 (16.2%) died. Patients with recurrence had significantly more frequent liver cirrhosis, more frequent history of previous treatment for HCC, higher total bilirubin, larger spleen size, larger total tumor size, higher tumor number, higher LS values, and lower platelet counts than those without recurrence (all P<0.05). On multivariate analysis, together with previous anti-HCC treatment history, patients with LS values >13.0 kPa were at significantly greater risk for recurrence after RFA, with a hazard ratio (HR) of 3.115 (95% confidence interval [CI], 1.238–7.842, P<0.05). Moreover, LS values independently predicted the mortality after RFA, with a HR of 9.834 (95% CI, 1.148–84.211, P<0.05), together with total bilirubin.ConclusionsOur data suggest that LS measurement is a useful predictor of HCC de novo recurrence and overall survival after RFA.

The Role of Contrast-Enhanced Ultrasound in Guiding Radiofrequency Ablation of Hepatocellular Carcinoma: A Retrospective Study

PurposeThe objective of the study was to determine the efficacy of contrast-enhanced ultrasound (CEUS) using ultrasound (US)-specific microbubbles in guiding radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). MethodsA retrospective analysis of 50 patients with HCC treated with CEUS guided RFA using perflutren at our institution was performed. CEUS images were first compared to B-mode US images performed at the same RFA session to determine the ability of CEUS to increase the conspicuity of lesions. A qualitative score (1 = poor, 2 = fair, 3 = excellent) was used to grade the ability to visualize the lesions. The preprocedure CEUS images were then evaluated using the most recent prior contrast enhanced computed tomography (CT) or magnetic resonance imaging (MRI). The efficacy of the treatment was evaluated with short-term follow-up imaging (median 1 month) for presence of residual or recurrent disease. ResultsCEUS allows at least fair visualization (score ≥2) in 78% (reader 1) and 80% (reader 2) of the lesions not visualized by B-mode US, and 50% (reader 1) and 42% (reader 2) of the lesions poorly visualized by B-mode US. Lesion appearances on CEUS are largely concordant with those on CT or MRI: 88% for reader 1, 96% for reader 2. With CEUS-guided RFA, complete response was achieved in the vast majority of the lesions at short-term follow-up: 82% for reader 1, 94% for reader 2. ConclusionsCEUS increases the conspicuity and provides better characterization of hypervascular HCC that are either not seen or poorly seen on B-mode US, and CEUS provides real-time guidance of RFA with good short-term treatment responses.

Radiofrequency ablation versus resection for the treatment of early stage hepatocellular carcinoma: a multicenter Australian study

Objectives. It remains unclear whether radiofrequency ablation (RFA) provides comparable outcomes to surgical resection (SR). We, therefore, compared survival outcomes of RFA to SR in patients with early stage and very early stage hepatocellular carcinoma (HCC). Methods. A multicenter retrospective analysis was performed in patients from five academic hospitals with Barcelona Cancer of the Liver Clinic (BCLC) stages 0–A HCC having RFA or SR as primary therapy. Results. From 2000–2010, 146 patients who received treatment with RFA (n = 96) or SR (n = 52) were identified. In BCLC A patients with ≤5 cm HCC, there was a trend of lower overall survival after RFA compared with SR (3- and 5-year survival: 62% and 37% vs. 66% and 62% respectively; p = 0.11). By multivariate analysis, RFA was an independent predictor of poor survival (hazard ratio = 2.26; 95% confidence interval: 1.02–5.03; p = 0.04). In ≤3 cm HCC (n = 109), the 3- and 5-year survivals in RFA and SR groups were 66% and 39%, and 69% and 59%, respectively, with no difference in the median survival (p = 0.41). Local recurrence was significantly higher after RFA compared to SR in HCC ≤5 cm (p = 0.006) with a trend of lower recurrence-free survival (p = 0.06) after RFA in HCC ≤3 cm. There were fewer major complications after RFA (2% vs. 8%). Conclusion. While SR is superior to RFA for the management of early stage BCLC A disease with ≤5 cm HCC, both appear effective as first-line treatment options for Western patients with small ≤3 cm tumors. Although safer than SR, RFA is associated with higher rates of tumor recurrence and local disease progression. Further prospective randomized controlled trials are warranted to compare these two modalities.

Percutaneous ultrasonography-guided radiofrequency ablation of hepatocellular carcinomas: usefulness of image fusion with three-dimensional ultrasonography

To evaluate the usefulness of fusion imaging with real-time ultrasonography (US) and three-dimensional (3D) US for the guidance of radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs) 2-5 cm in diameter. This study was conducted as a retrospective cohort study. It was approved by the institutional review board and informed consent was waived. During percutaneous RFA of HCCs, targeting was performed under conventional fusion imaging guidance, whereas monitoring and controlling were conducted under fusion with 3D US guidance. Technical success, technique effectiveness, incidence of major complications, and local tumour progression rate were evaluated. According to tumour size (small: <3 cm versus medium: 3-5 cm), the roundness indexes of the ablation zones and local tumour progression rates were compared. There were 29 small-sized HCCs (2.5 ± 0.3 cm) and 17 medium-sized HCCs (3.4 ± 0.5 cm). All RFA procedures were performed in a single RFA session. Both the technical success and technique effectiveness rates were 100%. One patient with medium-sized HCC developed a hepatic abscess (n = 1) as a major complication. The local tumour progression rate was 8.7% (4/46) with a mean follow-up period of 18.2 months. The roundness indexes of the ablation zone were not significantly different between small- and medium-sized HCCs, and the local tumour progression rates were also not significantly different between the two groups [3.4% (1/29) versus 17.6% (3/17); p = 0.135]. Image fusion with real-time US and 3D US is useful for the guidance of percutaneous RFA for HCCs 2-5 cm in diameter.