Efficacy Of Radiofrequency Ablation Research Articles

Safety and Efficacy of Radiofrequency Ablation of Thyroid Nodules-Expanding Treatment Options in the United States.

ContextRadiofrequency ablation (RFA) has only recently gained popularity in the United States for treatment of thyroid nodules (TNs), with a limited number of patients having undergone the procedure in this country.ObjectiveTo evaluate the safety and efficacy of RFA of TNs performed in an outpatient setting in the United States.MethodsThis is a retrospective, single-center study of 53 patients who underwent RFA of 58 TNs between November 2018 and January 2021. The reduction in volume of nodule, cosmetic and symptomatic improvement, effect on thyroid function, and complications following RFA were assessed.ResultsEleven out of 53 patients were excluded from the analysis. A total of 47 benign TNs (23 nonfunctioning thyroid nodules [NFTNs] and 24 autonomously functioning thyroid nodules [AFTNs]), were assessed after RFA. The median reduction in volume was 70.8% after a median follow-up period of 109 days, with symptomatic and cosmetic improvement (P < 0.0001). Compared with larger nodules, smaller nodules had greater volume reduction (P = 0.0266). RFA improved thyrotropin (TSH) in AFTNs (P value = 0.0015) and did not affect TSH in NFTNs (P value = 0.23). There were no major complications; however, 1 patient had self-limited local bleeding and another had transient voice change that recovered in 6 months.ConclusionRFA is a safe and efficacious treatment for symptomatic NFTNs and AFTNs in our population and is especially effective for smaller nodules. RFA should be considered an alternative for TNs in patients who cannot or do not want to undergo surgery.

Highlights from the literature

Radiofrequency ablation (RFA) is key in the therapy of early neoplasia in Barrett’s oesophagus (BO). However, a small proportion of patients experience neoplastic recurrence (NR) after complete eradication of intestinal...

ID: 3524051 ABLATIVE EFFECT OF ENDOBILIARY RADIOFREQUENCY ABLATION FOR HILAR CHOLANGIOCARCINOMA: EVALUATION BY USING PERORAL CHOLANGIOSCOPY AND INTRADUCTAL ULTRASONOGRAPHY

Recently, the endobiliary radiofrequency ablation (RFA) has been showed clinical efficacies in terms of stent patency and/or survival in a management of malignant biliary stricture (MBS). However, there are limitation in evaluating the thermal ablative effect of RFA in the bile duct only using ERCP and radiological diagnostic methods. In this study, we studied the efficacy of RFA by using peroral cholangioscopy (POC) and intraductal ultrasonography (IDUS) before and after endobiliary RFA in hilar cholangiocarcinoma.

Radiofrequency versus microwave ablation for hepatocellular carcinoma within the Milan criteria in challenging locations: a retrospective controlled study.

The aim of this study was to compare the safety and efficacy of radiofrequency ablation (RFA) with microwave ablation (MWA) for hepatocellular carcinoma (HCC) within the Milan criteria in challenging locations. This study retrospectively investigated 201 consecutive patients with Milan criteria HCCs who underwent RFA (RFA group, n = 150) or MWA (MWA group, n = 51) between January 2012 and December 2016. Overall survival (OS), recurrence-free survival (RFS), local tumor control, and treatment-related complications were compared between the two groups. Prognostic factors were analyzed using the Cox proportional hazard regression model. Median follow-up duration was 36.7months (range: 6.2-64.0months). Cumulative 1-, 3-, and 5-year OS rates were 97.9%, 92.3%, and 80.6% in the MWA group and 96.4%, 87.4%, and 78.2% in the RFA group, respectively, (P = 0.450). Cumulative RFS rates at 1, 3, and 5years were 93.2%, 74.4%, and 63.7% in the MWA group and 80.3%, 57.3%, and 49.6% in the RFA group, respectively, (P = 0.097). Multivariate analyses showed that variable categories "patient age above 65years" (P = 0.004) and "more than one tumor" (P = 0.004) were associated with overall mortality, and "patient age above 65years" (P = 0.048) and "tumor size greater than 3cm" (P = 0.009) were associated with inferior RFS. The incidences of major complications were not significantly different between the two groups (3.3% vs 3.9%, P = 0.843). RFA and MWA were associated with comparable safety and efficacy for HCC within the Milan criteria in challenging locations. Further study in a large, multi-center patient cohort is necessary to validate the results.

Formosanin C promotes the curative efficacy of ultrasound-guided radiofrequency ablation in a mouse model of breast cancer.

Breast cancer is the leading cause of tumor-associated death among women worldwide, and new therapeutic strategies are required to improve the post-surgery prognosis and quality of life of patients. Radiofrequency ablation (RFA) is a less invasive approach compared with traditional surgical resection to treat malignancies, and the combination of RFA and chemotherapeutic agents, including formosanin C (FC), can synergistically improve the curative effects against breast carcinoma. However, the detailed mechanisms remain unclear. In the present study, nude mice were used to identify the influence of FC on the therapeutic efficacy of RFA for breast cancer. Flow cytometry was performed to demonstrate the proportional alteration of CD8+ and CD45+ T cells with different biomarkers, including CD107a, IFNγ and TNFα. It was demonstrated that FC enhanced the therapeutic efficacy of RFA in breast cancer, while RFA combined with FC improved the proportion of IFNγ+ and TNFα+ CD8+ T cells and CD107a+ CD8+ T cells in tumor-infiltrating lymphocytes, thus increasing the immune responses caused by surgery and chemotherapy. The present study indicated that FC may promote the curative efficacy of ultrasound-guided RFA against breast tumor by regulating adaptive immune responses.

Radiofrequency Ablation for Cervical Metastatic Lymph Nodes in Children and Adolescents With Papillary Thyroid Carcinoma: A Preliminary Study

ObjectiveTo evaluate the safety and efficacy of radiofrequency ablation (RFA) for metastatic lymph nodes (LNs) in children and adolescents with papillary Thyroid Carcinoma (PTC).Materials and MethodsFrom December 2014 to March 2018, 10 metastatic LNs(mean volume 0.30 ± 0.38 ml, range 0.06-1.23ml) in 5 children and adolescents (3 females, 2 males; mean age 15.60 ± 2.97 years, range 12-19 years) with PTC treated by RFA were evaluated in this study. The mean number of surgical procedures performed before RFA was 1.2 (range 1-2) and the mean number of treated metastatic LNs per patient was 2 (rang 1-3). RFA was performed with an 18–gauge bipolar RF applicator under local anesthesia. Follow-up consisted of US and serum thyroglobulin (Tg) level at 1, 3, 6, 12 months and every 12 months thereafter.ResultsAll the patients were well tolerant to RFA procedure and no procedure-related complications occurred. During a mean follow-up time of 52.00 ± 21.44 months, the initial volume of LNs was 0.30 ± 0.38 ml, which significantly decreased to 0.01 ± 0.03 ml (P = 0.005) with a mean VRR of 99.28 ± 2.27%. A total of 9 metastatic LNs (90.00%) completely disappeared. After RFA, 2 patients developed newly metastases. One patient had additional RFA. The other one with multiple LN metastases underwent total thyroidectomy with central neck dissection.ConclusionAs a less invasive and effective technique, RFA may provide another alternative to the existing therapeutic modalities for cervical metastatic LNs in children and adolescents with PTC.

Predictor Analysis in Radiofrequency Ablation of Benign Thyroid Nodules: A Single Center Experience.

PurposeTo confirm the efficacy of ultrasound (US) guided radiofrequency ablation (RFA) in the treatment of benign thyroid nodules, we evaluated as primary outcome the technical efficacy and clinical success in a single center dataset. The secondary outcome was to find a correlation between nodules’ pre-treatment features and volume reduction rate (VRR) ≥75% at 12 months after RFA and during follow-up period.MethodsThis retrospective study included 119 consecutive patients (99 females, 20 males, 51.5 ± 14.4 years) with benign thyroid nodules treated in our hospital between October 2014 and December 2018 with a mean follow-up of 26.8 months (range 3–48). Clinical and US features before and after RFA were evaluated by a US examination at 1, 3, 6, 12 months and annually thereafter up to 48 months.ResultsThe median pre-treatment volume was 22.4 ml; after RFA we observed a statistically significant volume reduction from the first month (11.7 ml) to the last follow-up (p < 0.001 for all follow-up times). The median VRR was 47.1, 55.3, 61.2, 67.6, 72.8, 71.3, and 62.9% at 1, 3, 6, 12, 24, 36, and 48 months of follow-up respectively, showing a progressive significant improvement up to 24 months (VRRs 1 vs 3 months, 3 vs 6 months and 6 vs 12 months p < 0.001, 12 vs 24 months p = 0.05) while no differences at 24 vs 36 and 36 vs 48 months were observed. Symptoms improved significantly (complete resolution 64.35%, partial resolution 35.65%), and neck circumference was reduced as compared to pre-treatment (p < 0.001). Lower pre-treatment neck circumference (37.5 vs 36.0 cm, p = 0.01) was a positive predictor of VRR ≥75% at 12 months. Macrocystic echostructure (HR 2.48, p 0.046) and pre-treatment volume >22.4 ml (HR 0.54, p 0.036) were found to be independent positive and negative predictors of VRR ≥75% respectively. One-month post RFA VRR ≥50% represented the best positive predictor of technical success.ConclusionsThis study confirmed the efficacy of RFA in the treatment of benign thyroid nodules. In particular we show that by selecting macrocystic nodules smaller than 22.4 ml better long-term response can be achieved, which is predicted by an early shrinkage of the nodule.

CLINICAL AND BIOCHEMICAL OUTCOMES AFTER RADIOFREQUENCY ABLATION FOR ALDOSTERONE-PRODUCING ADENOMA AT KEIO UNIVERSITY HOSPITAL - 2020 ANNUAL REPORT

Objective: Total adrenalectomy of affected adrenal is the standard therapy for aldosterone-producing adenoma (APA), which is a curable subtype of primary aldosteronism (PA). However, there are cases in which total adrenalectomy could not be performed because of bilateral adenomas or incapability of operation under general anesthesia. For these cases radiofrequency ablation (RFA), which is minimally invasive and enables cortical-sparing treatment, could be a choice of treatment. A multicenter clinical trial of RFA for APA was performed in Japan from 2015 to 2016. The long-term efficacy of this treatment remains to be established, so we have assessed its effectiveness and safety annually and reported it at ISH 2018. The evaluation of clinical and biochemical outcomes has been extended. This time we report these outcomes 4 years after treatment. Design and method: The long-term efficacy of RFA for APA was monitored and analyzed. Results: 10 cases of APA were treated with RFA between June 2015 and March 2016. 7 cases were in valid follow-up at the end of November 2019. Aldosterone-renin ratio (ARR) returned to normal in all 7 cases. Hypertension was not cured in 2 cases (29%) though ARR were normal. Urinary albumin levels were improved in all cases. Follow-up CT images showed that the tumor vanished in 1 case (14%), shrank in 3 cases (43%) and unchanged in 3 cases (43%). There were no cases indicating adrenal insufficiency after RFA. Conclusions: In average 4-year follow-up after RFA, there were no cases suggesting recurrence. RFA for APA appears to be effective and safe.

Treatment Efficacy of Radiofrequency Ablation for Recurrent Tumor at the Central Compartment After Hemithyroidectomy.

OBJECTIVE. The aim of this study was to evaluate the efficacy of ultrasound (US)-guided radiofrequency ablation (RFA) for recurrent tumor in the central compartment after hemithyroidectomy. MATERIALS AND METHODS. The medical records of patients who underwent RFA for recurrent tumor after hemithyroidectomy between January 2008 and December 2018 were reviewed. Eight patients who underwent RFA for 10 recurrent tumors after hemithyroidectomy were included in our study population. Patients underwent follow-up US 1, 6, and 12 months after treatment and annually thereafter. The tumor volume reduction rate (VRR) was calculated as follows: VRR = ([initial volume - final volume] × 100) / initial volume. All patients were advised to undergo contrast-enhanced CT after tumor ablation. Complete tumor disappearance was defined as no visible treated tumor on follow-up US or CT. RESULTS. Mean tumor VRR was 97.8% ± 7.0% (SD) (range, 77.8-100%). Complete tumor ablation was achieved for all 10 recurrent tumors. Complete disappearance was confirmed in nine recurrent tumors, and one recurrent tumor showed a VRR of 77.8% on US but there was no enhancement on CT. All eight patients achieved no evidence of disease during mean follow-up of 33.0 months. RFA was tolerated by all patients; there were no major complications or procedure-related deaths. One patient experienced transient voice change during RFA. CONCLUSION. RFA can be considered to be an effective and safe alternative treatment method for recurrent tumor in the central compartment after hemithyroidectomy.

Catheter ablation of complex cardiac arrhythmias: Single-centre experience in Armed Forces

BackgroundComplex arrhythmia ablation remains a technical challenge despite advances in hardware and mapping techniques. The aim of the study was to analyse the efficacy of radiofrequency ablation of arrhythmias requiring complex electrophysiological procedures at a tertiary-care centre. MethodsA retrospective study was done for catheter ablation of arrhythmias performed at a single centre from Aug 2012 to Nov 2016 (4 years 4 months). The standard ablation involved conventional catheters with antegrade right heart and retrograde left heart access. The procedure was considered complex, if it involved 3 D electro-anatomical (EA) guidance for mapping or required special hardware and/or trans-septal puncture. ResultsOf 333 electrophysiology (EP) cases 265 qualified for ablation. The cohort of arrhythmias requiring complex procedure (n = 94) comprised of supraventricular 15 (15.9%), atrioventricular 43 (44.7%) and ventricular 36 (38.3%). The procedure used three-dimensional EA mapping in 31; trans-septal puncture for left atrial access in 40; and use of special catheters and sheaths in all 94 procedures. The overall success in the complex group after the first procedure was 87.2% versus 88.3% (P < 0.05), and after redo procedure it was 90.4% vs 94.7% (P < 0.05). There were three complications (pericardial perforation: 2; cardioembolism: 1) only in the complex group. The fluoroscopy time for complex was longer than that of the standard procedure (25.10 ± 6.32 versus 15.23 ± 5.33 min, P = 2.54). ConclusionArrhythmias requiring complex electrophysiological procedure for ablation have a comparable success rate to standard ablation procedure but at the cost of extra hardware, complications and fluoroscopy time.

Long term follow‐up results of ablation treatment for patients with small renal mass

The aim of this study is to evaluate the outcome of ablation therapy in our clinic for the treatment of patients with a small renal mass Materials and Methods: We retrospectively evaluated the technic and follow-up data of 30 patients with 36 tumours who underwent Radiofrequency Ablation (RFA) and Microwave Ablation (MWA) in our clinic. Demographic data, ablation type, tumour characteristics, peroperative and postoperative complications and treatment success of the patients were evaluated. A total of 36 tumours who underwent ablation treatments, 23 were treated with RFA, 13 with MWA. The mean tumour size was 28.9±6.92mm in RFA and 29.3±7.70mm in MWA. The mean follow-up period was 49.6±24.7months in patients with RFA and mean follow-up was 16±8.05months in MWA treatments. The overall success in MWA administration was calculated as 76.9%, while the overall success in RFA was 80%. Long-term oncologic efficacy of RFA appears to be successful in the treatment of T1a renal carcinomas. Further studies can be conducted to elucidate the influence of MWA on long-term oncological outcomes.

Review of the Safety of Bipolar Radiofrequency Ablation in Patients with Chronic Pain with Implantable Cardiac Rhythm Management Devices

Chronic pain, especially low back pain and hip pain, has been a growing public health concern that affects over 100 million Americans annually. Radiofrequency ablation (RFA) has distinct advantages over other chronic pain management modalities and its use has been increasing over the past decade. Among the growing population with comorbid conduction disorders and persistent pain, RFA and its potential interference with implantable cardiac devices is of concern.RFA is becoming a foundational element of persistent pain management and has been shown to be effective in a multitude of chronic pain syndromes. Cardiac implantable electronic devices (CIED), such as cardiac pacemakers or implantable cardioverter defibrillators, have been used in the treatment of cardiac conduction diseases for a number of decades. With our aging population, these diseases have increased in both incidence and prevalence. Chronic pain and cardiac conduction diseases are both common in our increasingly aging population. This study aims to determine if the literature supports the hypothesis that patients with CIEDs can safely use RFA with minimal to no interaction. Systematic assessment of literature with a modified approach with bipolar RFA. A narrative review with systematic assessment of the literature was carried out. In this review, we included randomized controlled trials (RCTs), open non-randomized control studies, prospective studies, retrospective studies, case series, and case reports. All types of radiofrequency utilized for pain management including pulsed and conventional were included. Outcome measures included interactions between the cardiovascular implantable electronic device (CIED) and radiofrequency ablation (RFA), adverse events, RFA efficacy in treating the pain using pain scores, and other complications. Our search criteria yielded 4 studies for inclusion, with inclusion of 33 patients and 71 bipolar radiofrequency for treatments. No adverse events or interactions occurred between the bipolar radiofrequency device and the implanted cardiac devices in any of these patients. Bipolar radiofrequency was utilized in all patients (n = 33). Overall there were no complications or malfunctions. Small sample size, narrative review. This study provides evidence that bipolar RFA can be safely used in patients with CIEDs for chronic pain provided that proper precautions are employed. Considerations for safe use are provided.

What Is the Role of Radiofrequency Ablation for Benign Thyroid Nodules?

What Is the Role of Radiofrequency Ablation for Benign Thyroid Nodules?

Higher Efficiency of Percutaneous Microwave (MWA) Than Radiofrequency Ablation (RFA) in Achieving Complete Response in Cirrhotic Patients with Early Hepatocellular Carcinoma.

Background: Contrasting data are available in the literature regarding the superiority of percutaneous microwave ablation (MWA) or radiofrequency ablation (RFA) in very early or early (BCLA 0 or A) hepatocellular carcinoma (HCC). Aims: The primary outcome was to compare the efficacy of RFA and MWA in achieving complete response in cirrhotic patients with early and very early HCC. The secondary outcomes were to evaluate the overall survival and the recurrence rate. Methods: A retrospective, observational, single-center study was performed. Inclusion criteria were liver cirrhosis, new diagnosis of a single node of HCC measuring a maximum of 50 mm or up to three nodules with diameter up to 35 mm, treatment with RFA or MWA. Radiological response was evaluated with multiphasic contrast-enhanced Computed Tomography or Magnetic Resonance Imaging at 5–7 weeks after thermal ablation. Complete response was defined when no vital tissue was detected after treatment. Results: Overall, 251 HCC patients were included in this study; 81 patients were treated with MWA and 170 with RFA. The complete response rate was similar in MWA and RFA groups (out of 331 nodules, 87.5% (91/104) were treated with MWA and 84.2% (186/221) were treated with RFA, p = 0.504). Interestingly, a subanalysis demonstrated that for 21–35 mm nodules, the probability to achieve a complete response using MWA was almost 5 times higher than for RFA (OR = 4.88, 95% CI 1.37–17.31, p = 0.014). Moreover, recurrence rate in 21–35 mm nodules was higher with RFA with respect to MWA (31.9% versus 13.5%, p = 0.019). Overall survival was 80.4% (45/56) when treated with MWA and 62.2% (56/90) when treated with RFA (p = 0.027). No significant difference was observed between MWA and RFA treatment in the 15–20 mm nodules group. Conclusion: This study showed that MWA is more efficient than RFA in achieving complete response in HCC nodules with 21 to 35 mm diameter.

Outcomes of radiofrequency ablation for anal high-grade squamous intraepithelial lesions.

Radiofrequency ablation (RFA) of high-grade squamous intraepithelial lesions (HSIL) is a promising minimally invasive technique but its oncologic and functional outcomes are not well studied. The primary outcome was the efficacy of RFA, and the secondary outcomes were the functional and anatomical anal changes related to RFA. This was a retrospective analysis of our prospectively collected database of patients who had RFA for HSIL at our institution, between August 2018 and March 2020. To be eligible for RFA, all patients had impairment of their immune function. Targeted ablation was applied in all cases, with 5 overlapping pulsations at the targeted HSILs (delivering 12J/cm2 per application) followed by circumferential, 2-pulsation (12J/cm2) overlapping anal ablation, to cover the entire anal transition zone. Patients were assessed for recurrence or metachronous disease at 3-month intervals by means of high-resolution anoscopy (HRA) and targeted biopsies. Anorectal manometry, endoanal ultrasound, the 36-Item Short Form and Massachusetts General Hospital-Sexual Functioning Questionnaire (MGH-SFQ) were assessed at baseline and 12months after intervention. We included a total of 12 patients with anal HSILs. The mean age was 38.6 (± 7.68) years, and 7 (58.3%) were males. Six were HIV positive, 2 had a primary immunodeficiency disease, and 4 were receiving immunosuppressive therapy. A mean of 2.1 anal HSILs per patient were treated. At 12months, high-resolution anoscopy showed that 7/12 (58.3%) patients had normal high-resolution anoscopy, 3/12 patients had recurrent HSILs, and 2/12 had a persistent lesion. Those lesions were treated with electrocautery, and reached complete response in the following the 6months (total of 18months). In particular, there were no metachronous lesions detected. Patients reported moderate to severe pain during the first 24h after RFA, but only mild discomfort was present at 30days. Patients were asymptomatic at their 6- and 12-month visits. RFA was not associated with changes in anorectal manometry or ultrasound examination. The 36-SF survey reported improvement in the general health domain (p = 0.038), while the MGH-SFQ showed improvements in sexual function. In this study, targeted plus circumferential RFA had a 58.3% efficacy rate for the treatment of anal HSIL in immunocompromised patients, achieving 100% eradication after adding electrocautery ablation. No metachronous lesions were detected. Patients presented relatively mild symptoms after the procedure, no changes in anorectal anatomy or function, and some improvements in their sexual function. These results seem promising in light of the high recurrence reported after HSIL treatment. Larger studies are needed to validate our results.

Experience With Changing Etiology and Nontransplant Curative Treatment Modalities for Hepatocellular Carcinoma in a Real-Life Setting—A Retrospective Descriptive Analysis

Hepatocellular carcinoma (HCC) has variable etiological risk factors. Radiofrequency ablation (RFA) and surgical resection (SR) are frequently used as curative treatment options. In the present study, we assessed the etiological factors and efficacy of RFA and SR in patients with unifocal HCC in a real-life setting. Of 870 patients with HCC seen over a period of nine years, 785 patients were assessed for stage and etiological risk factors. Of these, 110 (14%) patients with single HCC who were either treated with RFA (n= 72) or SR (n= 38) were evaluated for their outcomes in terms of overall survival (OS) and disease-free survival (DFS) over 3 years. Of 785 patients [median age 60 (range 51-65) years, males (n= 685, 87.3%)] with HCC, viral hepatitis [HBV and HCV with or without alcohol=502 (63.9%)] was the most common etiology; nonalcoholic steatohepatitis (NASH) and alcohol as an etiology showed increase over the years. About 677 (86.2%) patients had evidence of cirrhosis; NASH and HBV were predominant causes in noncirrhotic patients. Even though the groups were not matched, in 110 patients subjected to either RFA [mean tumor size, 2.2 (1.9-2.8) cm] or SR [mean tumor size, 7.1 (4.8-9.7) cm], tumor progression was observed in 49 (68%) and 16 (42%) patients in RFA and SR groups, respectively, with superior DFS in the SR group (P < 0.01). Of total 31 deaths, 20 (27.8%) deaths were in the RFA group and 11 (28.9%) in the SR group with no difference in OS at 3 years. Viral hepatitis with or without alcohol is the commonest etiological factor for HCC in Northern India; NASH and alcohol are increasing over the years. In a real-life setting, in patients with unifocal HCC, there is no difference in overall 3-year survival subjected to SR or RFA with better DFS in the SR group.

Delayed radiofrequency ablation efficacy in slow pathway ablation: a case report.

BackgroundThe delayed effect of radiofrequency (RF) ablation was described in cases of accessory pathway and premature ventricular contraction ablation, as well as delayed atrioventricular (AV) block after slow pathway ablation.Case summaryWe report a case of a female patient with AV nodal re-entry tachycardia (AVNRT), in whom the first electrophysiology study ended with acute failure of slow pathway ablation, despite using long steerable sheath, both right and left-sided ablation with >15 min of RF energy application and repeatedly achieving junctional rhythm. Six weeks afterwards, during scheduled three-dimensional electroanatomical mapping procedure, there was no proof of dual AV nodal conduction nor could the tachycardia be induced. Also, the patient did not have palpitations between the two procedures nor during the 12-month follow-up period.DiscussionThis case illustrates that watchful waiting for delayed RF ablation efficacy in some cases of AVNRT ablation could be reasonable, in order to reduce the risk of complications associated with slow pathway ablation.

Long-Term Efficacy of Radio Frequency Ablation for Superficial Lesions of the Tracheobronchial Tree.

Long-Term Efficacy of Radio Frequency Ablation for Superficial Lesions of the Tracheobronchial Tree.

The Role of 18F-FDG PET/CT in Evaluating the Efficacy of Radiofrequency Ablation in Metastatic and Primary Liver Tumors: Preliminary Results.

Objectives:The aim of the study was to investigate the role of 18fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for evaluating the efficacy of radiofrequency ablation (RFA) in primary and metastatic liver tumors compared with contrast-enhanced ultrasound examination (CEUS) and to find its place in overall staging and the follow-up diagnostic algorithm.Methods:PET/CT examinations were performed 2 months after RFA for 20 patients with a total of 34 liver lesions. CEUS was performed within 10 days after PET/CT, and the results were compared. Seven patients were staged with PET/CT and the others with a contrast-enhanced CT.Results:A total of 48 18F-FDG PET/CT examinations were performed. We observed complete response in 8 patients (40%), 2 patients (10%) had stable disease, one (5%) had partial response, and 9 patients (45%) had progression (including 2 cases with extrahepatic involvement). Compared with CEUS, there was a mismatch in 3 cases. Five patients underwent additional RFA for 7 lesions.Conclusion:According to our preliminary data, PET/CT may be a valuable method, with comparable or eventually even better sensitivity than CEUS, for early evaluation of the efficacy of RFA for the treatment of metastatic and primary liver lesions and planning of future treatment. PET/CT might be recommended as a staging method before undergoing RFA of liver lesions for determining the local extent of the disease in the liver in combination with CEUS with an advantage in visualization of extrahepatic involvement. However, more patients need to be investigated in order to demonstrate and confirm the obtained results with certainty.

Application and Utility of Radiofrequency Ablation in the Treatment of Benign Thyroid Nodules

Most thyroid nodules are benign and asymptomatic; however, some will ultimately cause compressive symptoms or develop autonomous function. Radiofrequency ablation (RFA) has emerged as a novel treatment option in lieu of other minimally invasive ablative techniques. This article discusses the role of RFA in the management of benign thyroid nodules and reviews recent literature comparing outcomes between RFA, surgery, and medical therapy. Multiple studies have demonstrated the safety and efficacy of RFA in the treatment of autonomously functioning thyroid nodules (AFTN) and symptomatic, cold nodules (SCN). The “moving shot” technique has proven successful in normalizing thyroid function for ATFNs and decreasing cosmetic/symptomatic concerns for SCNs after a single treatment. Radiofrequency ablation is a viable treatment option for the treatment of AFTNs and SCNs in patients who refuse or are otherwise unable to tolerate surgery. Patient selection is critical and performance at high-volume centers is necessary for best outcomes.