Therapeutic Efficacy Of Radiofrequency Ablation Research Articles

LncENST Suppress the Warburg Effect Regulating the Tumor Progress by the Nkx2-5/ErbB2 Axis in Hepatocellular Carcinoma.

The therapeutic efficacy of radiofrequency ablation (RFA) against liver cancer is often limited by proliferation and metastasis of residual tumor cells. These phenomena are closely associated with the Warburg effect, wherein ErbB2 is activated. While RFA inhibits the Warburg effect of residual tumor cells at the early stage, the specific mechanisms remain unclear. We explored the regulatory relationship between the long noncoding RNA ENST00000570843.1 (lncENST) and ErbB2 using lentiviral transfection of lncENST and ErbB2 overexpression/interference vectors in in vitro and in vivo models of hepatocellular carcinoma in the presence of sublethal heat at 50°C. ErbB2-mediated Warburg effect was suppressed by lncENST, as manifested by reduced glucose uptake and lactic acid production in SMMC-7721 cells. lncENST also increased tumor apoptosis and inhibited tumor progression in nude Balb/c mice for up to 28 days after RFA. Additionally, we predicted through bioinformatic analysis that the promoter of ErbB2 binds to the transcription factor Nkx2-5, resulting in a negative regulatory effect. This speculation was confirmed by chromatin immunoprecipitation of the Nkx2-5 protein and ErbB2, indicating that ErbB2 transcription was curbed by Nkx2-5. We propose that lncENST downplays the Warburg effect in residual tumor cells by downregulating ErbB2 via Nkx2-5 activation. This study is aimed at providing molecular targets that can prevent residual tumor cell proliferation after RFA, with clinical significance in hepatocellular carcinoma treatment.

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

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. 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. The success rate of the fusion system was 82.7% (115/139) per patient. The mean sonographic scan time for fusion was 154.4 ± 108.4s. 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 3years. 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 3b, Nonrandomized prospective study.

Combined liver resection and radiofrequency ablation for bilobar multiple colorectal liver metastasis

Combined liver resection and radiofrequency ablation for bilobar multiple colorectal liver metastasis

Electrophysiological characteristics and therapeutic efficacy of radiofrequency ablation of focal atrial tachycardia originating from the right atrial appendage during pregnancy

Objective: To analyze the electrophysiological characteristics and the therapeutic efficacy of irrigated-tip catheter radiofrequency ablation(RFA) without radiation for pregnant women with focal atrial tachycardia(AT) originating from the right atrial appendage (RAA). Methods: Data from 55 women with focal AT, who underwent radiofrequency ablation (RFA) in the First Affiliated Hospital of Zhengzhou University from October 2016 to March 2019, were screened. 2 non-pregnant women with right atrial appendage tachycardia (RAAT) and 4 pregnant women with non-RAAT were excluded. The remaining 49 cases were divided into RAAT during pregnancy group (n=6, including 4 cases of tachycardia-induced cardiomyopathy) and non-pregnant and non-RAAT group (control, n=43). Under the guidance of three-dimensional mapping system, the earliest activation site was identified, RFA with the irrigated catheter without x-ray fluoroscopy was performed in RAAT patients during pregnancy, all patients in control group underwent non-zero-ray ablation. Patients were followed up at 3, 6, 12 months post procedure, and yearly follow up thereafter in outpatient clinic. Electrocardiogram or Holter monitoring was performed during follow up. AT recurrence and surgical complications were recorded during follow up. At 6 months after RFA, echocardiography examination and laboratory examination including N-terminal B-type brain natriuretic peptide measurement were performed in the pregnant patients, delivery results were also recorded in the pregnant patients. The electrophysiological characteristics of RAAT during pregnancy were analyzed, the therapeutic efficacy of RFA was compared between the two groups. Results: This study is a retrospective study. Age ((30.7±6.2)years vs. (57.2±11.7)years), left ventricular ejection fraction ((46.0±12.8)% vs. (60.1±5.9)%), proportions of organic heart disease (0% vs. 58%) were significantly lower in the RAAT patients during pregnancy group than in control group (P<0.05), while proportions of patients with persistent tachycardia (100% vs. 7%), symptoms of chest distress and palpitation (6/6 vs. 49%) and left ventricular ejection farction≤50% (4/6 vs. 9%) were significantly higher in RAAT group than in control group (P<0.05), heart rate was similar between the two groups ((163.7±11.1)beats/minutes vs. (153.7±15.2)beats/minutes, P>0.05). The characteristic P-wave morphology was observed in RAAT patients during pregnancy, i.e, P wave was mostly upright (5/6) in inferior-leads (Ⅱ, Ⅲ, aVF) and in lead I and aVL, deep and wide negative P wave was found in V1 lead (5/6), and gradually became positive from V2-V6. The mean tachycardia cycle length was (361.7±38.5) ms. Three-dimensional mapping showed that the origin points of the 6 RAAT pregnant patients were all scattered in the local region, the local region was ablated accordingly, 2 patients (2/6) received extensive ablation of local areas. Immediate successful rate was similar between the two groups (6/6 vs. 93%). During follow up ((15.3±4.0) months), no complications were observed after RFA, postoperative recurrence rate was similar (1/6 vs. 12%). Uncomplicated delivery was reported in all 6 pregnant RAAT post ablation. Normal cardiac structure and function was observed in the 4 pregnant patients with tachycardia-induced cardiomyopathy post ablation. Compared to pre-ablation phase, reduced left atrial dimension ((30.3±1.3) mm vs. (36.8±6.7) mm, P>0.05), increased left ventricular ejection fraction ((64.0±2.9)% vs. (39.8±10.7)%), reduced left ventricular end-diastolic dimension ((44.8±4.0) mm vs. (60.0±2.9) mm) and reduced N-terminal B-type natriuretic peptide value ((136.2±47.5) ng/L vs. (3 408.4±901.3) ng/L) were observed at 6 months post ablation (P<0.05). Conclusion: The electrophysiological characteristics are suggestive for focal AT originating from RAA during pregnancy. Under the guidance of 3-dimension activation mapping, no fluoroscopic RFA with irrigated-tip catheter is a safe and effective strategy for the treatment of focal RAAT during pregnancy.

Percutaneous Radiofrequency Ablation With a Multiple-Electrode Switching System for Medium-Sized Hepatocellular Carcinomas

Objective This study aimed to retrospectively evaluate the safety and short-term therapeutic efficacy of radiofrequency ablation (RFA) with a multiple-electrode switching system (MESS) to treat medium-sized (3.1–5.0 cm) hepatocellular carcinomas (HCCs). Summary of Background Data Conventional monopolar RFA is limited in achieving local control for tumors larger than 3 cm. Therefore, MESS-RFA was developed, and it can create a sufficiently large ablation volume, including the target tumor and a 5- to 10-mm safety margin in medium-sized tumors. Methods We performed a total of 168 RFAs with a MESS for 166 patients. The patients were treated under ultrasonographic guidance by a percutaneous switching system RFA with a multichannel RF generator and 2 or 3 internally cooled electrodes. Technical effectiveness, local progression, and remote recurrence of HCC were determined. Results For the 166 isolated HCC tumors, the complete ablation rate of MESS-RFA was 98.79% (164 of 166). Mean ablation time per procedure was 12.33 ± 3.01 minutes; mean ablation diameter was 5.79 ± 0.61 cm. The complication rate was 2.41%. During follow-up (averaging 16.54 months), local tumor progression occurred in 15 of 166 patients (9.03%) with technical effectiveness, whereas new HCCs were detected in 40 of 166 patients (24.09%). Multivariate analyses revealed that local tumor progression was only associated with serum α-fetoprotein levels above 100 ng/mL as a risk factor. Conclusion MESS-RFA for achieving sufficient ablation volume is safe and efficient. This method also showed relatively successful therapeutic effectiveness on short-term follow-up in the treatment of medium-sized HCCs.

The Effect of Esophageal Varices on the Outcome of Radiofrequency Ablation in Patients with Hepatocellular Carcinoma

Abstract Background: Little is known about the effect of esophageal varices on the outcome of radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC). Aim of Study: To determine the therapeutic efficacy of radiofrequency ablation of hepatocellular carcinoma associated with esophageal varices, and the important risk factors that affect the outcome. Patients and Methods: 121 of 168 patients with portal hypertension had esophgeal varices, underwent RF ablation as a treatment for a single HCC (9 5cm). Therapeutic efficacy was evaluated. Logistic regression analyses of risk factors for occurrence of complication and multivariate cox-regression analyses for overall survival were detected. Results: Patients with HCC and esophageal varices had a complete ablation rate of 88.4%. Portal vein thrombosis was the most type of complication. By univariate analysis, thrombocytopenia (p=0.032) was independent risk factor of complications. By multivariate analysis, left lobe location of HCC (p=0.015) was independent risk factor of complications and subcapsular location of HCC (p=0.019), was independent prognostic factors for survival. Conclusion: This current study has proven that patients with portal hypertension and esophageal varices can tolerate RF ablation of HCC. Dealing caution as regard correction of thrombocytopenia and professionally as regard location of HCC, we can improve the outcome of RF ablation.

Use of intra-procedural fusion imaging combining contrast-enhanced ultrasound using a perflubutane-based contrast agent and auto sweep three-dimensional ultrasound for guiding radiofrequency ablation and evaluating its efficacy in patients with hepatocellular carcinoma

Purpose This study evaluated the usefulness of intraprocedural contrast-enhanced ultrasound (CEUS)/ultrasound (US) fusion imaging using a perflubutane-based contrast agent combined with preprocedural auto sweep three-dimensional US to obtain volume data for guidance and evaluation of the therapeutic efficacy of radiofrequency ablation (RFA). Methods This uncontrolled clinical trial included 50 hepatocellular carcinomas (HCCs) with a mean diameter of 15.3 mm that had been treated by RFA. The efficacy of RFA was evaluated by CEUS/US fusion imaging during the procedure. If the ablation was deemed to be inadequate, further ablation was performed until adequate ablation was achieved. Contrast-enhanced computed tomography (CECT) or contrast-enhanced magnetic resonance imaging (CEMRI) was performed a month after RFA, and the images obtained using each modality were reviewed to evaluate the efficacy of RFA. Results Thirty-three of the 50 lesions were evaluated by CEUS/US fusion imaging as having been adequately ablated after the first RFA procedure. The ablation was evaluated as inadequate in the remaining 17 lesions, for which additional ablation was performed. Ninety-eight (49/50) of all HCCs were evaluated as having been eventually adequately ablated on intraprocedural CEUS/US fusion imaging. The concordance rate for evaluations between intraprocedural CEUS/US fusion imaging and CECT/CEMRI performed 1 month after RFA was 88% (44/50). The kappa value for agreement between the two methods of evaluation was 0.792. Conclusion Intraprocedural fusion imaging combining CEUS and auto sweep three-dimensional US appears to be a useful modality for RFA guidance and evaluation of therapeutic efficacy of RFA in patients with HCC.

Fusion imaging with contrast-enhanced ultrasonography for evaluating the early therapeutic efficacy of radiofrequency ablation for small hypervascular hepatocellular carcinomas with iso-echoic or unclear margins on conventional ultrasonography

Fusion imaging with contrast-enhanced ultrasonography for evaluating the early therapeutic efficacy of radiofrequency ablation for small hypervascular hepatocellular carcinomas with iso-echoic or unclear margins on conventional ultrasonography

Fusion imaging with contrast-enhanced ultrasonography for evaluating the early therapeutic efficacy of radiofrequency ablation for small hypervascular hepatocellular carcinomas with iso-echoic or unclear margins on conventional ultrasonography.

We evaluated the efficacy of fusion imaging combining contrast-enhanced ultrasonography (CEUS) images and arterial phase contrast-enhanced CT (CECT) or hepatobiliary phase magnetic resonance imaging with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (EOB-MRI) images for the early evaluation of the effectiveness of radiofrequency ablation (RFA) for small hypervascular hepatocellular carcinoma (HCC) with iso-echoic or unclear margins on conventional US. Forty HCCs (22 iso-echoic and 18 unclear margin lesions) with mean diameters of 13.7mm were treated using RFA under the guidance of fusion imaging with CEUS. The adequacy of RFA was evaluated using fusion imaging with CEUS 1day after RFA. CECT or EOB-MRI was performed 1month after RFA. We reviewed the images obtained using both modalities. When the 1-month CECT or EOB-MRI scans were used as the reference standard, the sensitivity, specificity, and accuracy of the 1-day fusion imaging for the diagnosis of the adequate ablation of these HCCs were 97, 100, and 98%, respectively; the kappa value for the agreement between the findings using the two modalities was 0.655. Fusion imaging with CEUS appears to be a useful method for the early evaluation of the efficacy of RFA for the treatment of HCCs with iso-echoic or unclear margins on conventional US.

Enhanced efficacy of radiofrequency ablation for hepatocellular carcinoma using a novel vascular disrupting agent, CKD-516.

CKD-516 is a novel vascular disrupting agent that shuts down intratumoral blood flow. We therefore hypothesized that concomitant administration of CKD-516 would enhance the therapeutic efficacy of radiofrequency ablation (RFA) by reducing heat sink effects. We assessed the effects of the combination of CKD-516 and RFA in a rat orthotopic hepatocellular carcinoma (HCC) model. Rat HCC cells (N1-S1) were engrafted into the hepatic lobe of Sprague-Dawley (SD) rats. Mice were randomly divided into two groups: RFA-only and CKD-RFA. In the CKD-RFA group, CKD-516 was administered by intraperitoneal injection 2h before RFA. Ablation zone size was measured on triphenyltetrazolium chloride-stained specimens. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed to evaluate the area of apoptosis/necrosis in the ablation zone. Immunohistochemistry with anti-CD31 antibody was performed to evaluate the effect of CKD-516 on tumor vessels. Ablation zone size was significantly larger in the CKD-RFA group than in the RFA-only group (243.10±74.39 versus 123.30±28.17mm2, p<0.001). On TUNEL staining, the area of apoptosis/necrosis was also significantly larger in the CKD-RFA group than in the RFA-only group (274.44±140.78 versus 143.74±90.13mm2; p=0.006). Immunohistochemistry with anti-CD31 antibody revealed patent tumor vessels in the RFA-only group, while collapsed vessels were seen in the CKD-RFA group, indicating a vascular shutdown effect of CKD-516. Concomitant administration of CKD-516 during RFA can increase the ablation zone of tumors due to its vascular disrupting effect.

Efficacy comparison of radiofrequency ablation and hepatic resection for hepatocellular carcinoma: A meta-analysis.

The objective of this study is to compare the therapeutic efficacy of radiofrequency ablation (RFA) and hepatic resection (HR) for the treatment of hepatocellular carcinoma (HCC). A literature search was performed for comparative studies reporting outcomes of both RFA and HR for HCC. Pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated. A total of 4812 patients with HCC were included, with 2419 in the RFA group and 2393 in the HR group. The 3- and 5-year overall survival rates in the HR group were significantly higher than those in the RFA group (OR: 0.68, 95% CI: 0.58-0.79, P < 0.00001; OR: 0.57, 95% CI: 0.50-0.65, P < 0.00001, respectively). 1-, 3-, 5-year disease-free survival and correspond recurrence-free survival rates were all better in HR group. RFA gets promising clinical outcomes for HCC treatments but is not yet comparable to surgery. HR is still the first-line treatment for HCC.

Utilizing gemstone spectral CT imaging to evaluate the therapeutic efficacy of radiofrequency ablation in lung cancer.

To evaluate the therapeutic efficacy of radiofrequency ablation (RFA), quantitative water-based, and iodine-based images of gemstone spectral computed tomography (CT) were analyzed. 30 patients underwent lung RFAs from March 2012 to March 2013. Through enhanced chest scans, we obtained the tumor size values by conventional CT images, and quantitatively analyzed the densities of iodine and water in lung tumors from water-based and iodine-based material decomposition images. Tumors in 22 cases increased in size after RFA while there was no detectable change in the remaining 8 cases. Through water-based material decomposition images, the water content in the tumors increased from (1014.76±6.83mg/mL) to (1022.71±10.16mg/mL) after RFA, and this difference was significant (t=-2.329, p<0.05). Through iodine-based material decomposition images, the iodine content in the tumors was 2.49±0.74mg/mL before RFA. The tumors were mostly or completely necrotized after RFA and the iodine content in the area of necrosis reduced to 0.45±0.29mg/m (t=11.072, p=0.000). By comparing the tumor size, water content and iodine content before and after RFA, we can visualize the morphology and metabolic states of the tumors and evaluate the therapeutic efficiency.

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.

Intravoxel Incoherent Motion Diffusion Weighted MR Imaging for Monitoring the Instantly Therapeutic Efficacy of Radiofrequency Ablation in Rabbit VX2 Tumors without Evident Links between Conventional Perfusion Weighted Images.

ObjectiveTo investigate the intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) as a potential valuable marker to monitor the therapy responses of VX2 to radiofrequency ablation (RF Ablation).MethodsThe institutional animal care and use committee approved this study. In 10 VX2 tumor–bearing rabbits, IVIM-DWI examinations were performed with a 3.0T imaging unit by using 16 b values from 0 to 800 sec/mm2. The true diffusion coefficient (D), pseudodiffusion coefficient (D*) and perfusion fraction (f) of tumors were compared between before and instantly after RF Ablation treatment. The differences of D, D* and f and conventional perfusion parameters (from perfusion CT and dynamic enhanced magnetic resonance imaging, DCE-MRI) in the coagulation necrosis area, residual unablated area, untreated area, and normal control had been calculated by compared t- test. The correlation between f or D* with perfusion weighted CT including blood flow, BF (milliliter per 100 mL/min), blood volume, BV (milliliter per 100 mL/min), and capillary permeability–surface area, PMB (as a fraction) or from DCE-MRI: transfer constant (Ktrans), extra-vascular extra-cellular volume fraction (Ve) and reflux constant (Kep) values had been analyzed by region-of-interest (ROI) methods to calculate Pearson’s correlation coefficients.ResultsIn the ablated necrosis areas, f and D* significantly decreased and D significantly increased, compared with residual unblazed areas or untreated control groups and normal control groups (P < 0.001). The IVIM-DWI derived f parameters showed significant increases in the residual unablated tumor area. There was no significant correlations between f or D* and conventional perfusion parameters.ConclusionsThe IVIM-DW derived f, D and D* parameters have the potential to indicate therapy response immediately after RF Ablation treatment, while no significant correlations with classical tumor perfusion metrics were derived from DCE-MRI and perfusion-CT measurements.

Abstract P1-02-07: Contrast-enhanced ultrasound for evaluation of therapeutic efficacy of radiofrequency ablation for primary breast cancer

Abstract &amp;lt;Purpose&amp;gt; To evaluate therapeutic efficacy of percutaneous ultrasound (US) guided radiofrequency (RF) ablation therapy for primary breast cancer using contrast-enhanced US. &amp;lt;Methods and Materials&amp;gt; The study was approved by the institutional ethics committee, and written informed consent was obtained. Between January 2012 and April 2014, 25 patients with biopsy-confirmed T1 breast cancer underwent RF ablation therapy in one institution. We examined 25 patients with 25 T1 breast cancers by contrast-enhanced MRI/CT, and contrast-enhanced US before and after RF ablation therapy. US guided RF abltion was performed using a 17-gauge internally cooled electrode (Cool-TipTM, Valleylab, Boulder, CO, USA) under general anesthesia. After injection 0.015mL/kg body weight of Sonazoid®(perflubutane), contrast-enhanced US was performed at a low mechanical index (0.17-0.24). Therapeutic success was defined as a lack of contrast enhancement by contrast-enhanced MRI, US and non-viable cancer tissues by US guided vacuum assisted biopsy (VAB) or core needle biopsy (CNB). &amp;lt;Results&amp;gt; Contrast-enhanced US and MRI four weeks or more after RF ablation therapy showed ablation zones and adequate tumor necrosis in all 25 cancer lesions treated. Contrast-enhanced US made it possible to see that tumor vessels of treated lesions had disappeared after treatment. Contrast enhanced MRI showed a lack of stain with ring-like enhancement of ablation zone and non-viable tissues were seen by VAB and/or CNB in 25 ablation zones. &amp;lt;Conclusion&amp;gt; Contrast-enhanced US using Sonazoid® was useful modalities for evaluating the efficacy of RF ablation therapy in breast cancer lesions. Citation Format: Toshikazu Ito, Jyunji Okayama, Kumiko Uji, Masaaki Izukura. Contrast-enhanced ultrasound for evaluation of therapeutic efficacy of radiofrequency ablation for primary breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P1-02-07.

Comparative analysis of radiofrequency ablation and resection for resectable colorectal liver metastases

To evaluate the therapeutic efficacy of radiofrequency ablation (RFA) for resectable colorectal liver metastases (CRLM) compared with that of resection. Between June 2004 and June 2009, we retrospectively analyzed 29 patients with resectable CRLMs; 17 patients underwent RFA, and 12 underwent hepatic resection. All of the patients were informed about the treatment modalities and were allowed to choose either of them. RFA including an intraoperative approach was performed by a radiologist; otherwise, hepatic resection was performed by a surgeon. Comparative analysis of the two groups was performed, including comparisons of gender, age, and clinical outcomes, such as primary tumor stage and survival rates. The mean tumor size was significantly larger in the resection group (3.59 cm vs 2.02 cm, P < 0.01), and the 5-year overall survival (OS) rate for all patients was 44.7%. There was no difference in the 5-year OS rates between the RFA and resection groups (37.8% vs 66.7%). Univariate analysis indicated significantly lower 5-year OS rates for patients with a tumor size > 3 cm. The 5-year disease-free survival (DFS) rates were 17.6% and 22.2% in the RFA and resection groups, respectively (P = 0.119). Univariate analysis revealed that in cases of male gender, age > 65 years, T stage < IV, absence of lymphatic metastasis, and tumor size > 3 cm, RFA resulted in significantly inferior 5-year DFS rates compared with surgical resection. Surgical resection revealed superior outcomes in the treatment of resectable CRLMs, particularly in cases with a hepatic tumor size > 3 cm.

Prospective comparative study of cool-tip radiofrequency ablation and surgical resection for hepatocellular carcinoma

Objective The aim of this study was to compare the therapeutic efficacy of radiofrequency ablation (RFA) and surgical resection for the patients with hepatocellular carcinoma (HCC).

Radiofrequency ablationvshepatic resection for solitary colorectal liver metastasis: A meta-analysis

To evaluate the comparative therapeutic efficacy of radiofrequency ablation (RFA) and hepatic resection (HR) for solitary colorectal liver metastases (CLM). A literature search was performed to identify comparative studies reporting outcomes for both RFA and HR for solitary CLM. Pooled odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model. Seven nonrandomized controlled trials studies were included in this analysis. These studies included a total of 847 patients: 273 treated with RFA and 574 treated with HR. The 5 years overall survival rates in the HR group were significantly better than those in the RFA group (OR: 0.41, 95% CI: 0.22-0.90, P = 0.008). RFA had a higher rate of local intrahepatic recurrence compared to HR (OR: 4.89, 95% CI: 1.73-13.87, P = 0.003). No differences were found between the two groups with respect to postoperative morbidity and mortality. HR was superior to RFA in the treatment of patients with solitary CLM. However, the findings have to be carefully interpreted due to the lower level of evidence.

Comparative analysis of radiofrequency ablation and surgical resection for colorectal liver metastases

PurposeTo evaluate the comparative therapeutic efficacy of radiofrequency ablation (RFA) and hepatic resection for the treatment of colorectal liver metastasis (CRLM).MethodsBetween 1996 and 2008, 177 patients underwent RFA, 278 underwent hepatic resection and 27 underwent combination therapy for CRLM. Comparative analysis of clinical outcomes was performed including number of liver metastases, tumor size, and time of CRLM.ResultsBased on multivariate analysis, overall survival (OS) correlated with the number of liver metastases and the use of combined chemotherapy (P < 0.001, respectively). Disease-free survival (DFS) also correlated with the number of liver metastases (P < 0.001). In the 226 patients with solitary CRLM < 3 cm, OS and DFS rates did not differ between the RFA group and the resection group (P = 0.962 and P = 0.980). In the 70 patients with solitary CRLM ≥ 3 cm, DFS was significantly lower in the RFA group as compared with the resection group (P = 0.015).ConclusionThe results indicate that RFA may be a safe alternative treatment for solitary CRLM less than 3 cm, with outcomes equivalent to those achieved with hepatic resection. A randomized controlled study comparing RFA and resection for patients with single small metastasis would help to determine the most efficient treatment modalities for CRLM.

Usefulness of the hyperechoic rim for assessing the therapeutic efficacy of radiofrequency ablation in hepatocellular carcinoma patients

During radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), a hyperechoic rim develops around the HCC nodules. The usefulness of the hyperechoic rim to guide treatment was assessed. RFA was first performed in pig livers to determine the significance of the hyperechoic rim. Fifty-five patients with 75 HCC nodules had received RFA for the treatment of HCC. For those patients, we evaluated whether conventional ultrasonography (US) could be used instead of contrast-enhanced computed tomography (CECT) and contrast-enhanced ultrasonography (CEUS) using virtual imaging. Finally, 31 patients with 45 HCC nodules received RFA, and the degree of ablation was assessed based on the hyperechoic rim. Repeated RFA was done when ablation appeared incomplete. In the pig livers, the hyperechoic rim was found to be related to the presence of dead cells. The preliminary study showed that US could be used instead of CECT and CEUS to evaluate the degree of ablation caused by RFA. Because hepatic vessels in the back side of the hyperechoic rim were not clear by the artifact, we used the distance from the surface of the liver to the hyperechoic rim for evaluation. By analyzing the extent of the hyperechoic rim, it was noted that incomplete ablation was achieved in 17 of 31 patients (21 of 45 HCC nodules). These patients were re-treated with RFA within 5-15 min of the first RFA. This study shows that the hyperechoic rim is related to the presence of dead and necrotic tissues. Thus, assessment of the hyperechoic rim's characteristics allows one to evaluate the efficacy of RFA.