Efficacy Of Radiofrequency Ablation Therapy Research Articles

Multicenter study to evaluate the efficacy and standardize radiofrequency ablation therapy for early breast cancer.

e12570 Background: Early-stage breast cancer is increasingly detected by screening mammography, and we aim to establish radiofrequency ablation therapy (RFA) as a minimally invasive, cost-efficient, and cosmetically acceptable local treatment. In our Phase I study, localized tumors with a maximum diameter of 2 cm, preoperatively diagnosed by imaging and histopathology, were treated with RFA. A 90% complete ablation rate was confirmed histopathologically. Our phase II multicenter study of RFA without resection for early breast cancer will evaluate the long-term safety and efficacy of RFA as well as its cosmetic results, which are a perceived advantage of this technique. Methods: From Nov. 2009 to Nov. 2012, 58 patients with early-stage breast cancer received non-surgical RFA therapy. Patients had localized solitary N0 tumors with a maximum diameter of 1 cm. In our experimental therapy, a radiofrequency electrode needle is inserted through the skin into the breast lesion under imaging guidance, followed by thermal ablation with radiofrequency waves. RFA will be conducted under general anesthesia. The Cool-tip™ RF Ablation Single Electrode Kit (Medtronic, CO, USA) will be used to standardize the evaluation of the ablation effect. They underwent RFA and SNB under general anesthesia and adjuvant therapy and breast radiation. Follow-up evaluation for residual tumor at 3, 6, and 12 months after RFA included clinical examination, diagnostic imagings and vacuum-assisted biopsy. Surgical resection was recommended for patients with suspected residual disease or incomplete ablation. The primary endpoint was the frequency of adverse events. Secondary endpoints included the complete ablation rate and ipsilateral breast relapse-free rate. Results: The follow-up period ranged from 15 to 109 months (median, 85 months). The 57 patients completed the non-surgical RFA procedure and underwent diagnostic imaging and needle biopsy after 3 months. Seven patients with suspected incomplete ablation underwent surgical resection; incomplete ablation was confirmed in 5 (8.6%, 2 with invasive and 3 with non-invasive ductal carcinoma). During subsequent follow-up, 1 patient each was diagnosed with contralateral breast cancer and ipsilateral breast tumor relapse. No distant recurrence was documented. Cosmetic results were excellent in 94% of patients. Conclusions: Our phase II multicenter study of RFA without resection for early breast cancer will evaluate the long-term safety and efficacy of RFA as well as its cosmetic results, which are a perceived advantage of this technique. Clinical trial information: UMIN000008675 .

Catheter ablation of common atrioventricular nodal reentry tachycardia using the conventional method

Background and objective: Atrioventricular nodal reentry tachycardia is the commonest type of supraventricular tachycardia referred to the electrophysiology laboratory. It constitutes about two thirds of the supraventricular tachycardia admitted to the emergency department. The mechanism of this tachycardia is reentry. This study aimed to evaluate the efficacy of radiofrequency ablation therapy in atrioventricular nodal reentry tachycardia as the first line treatment using the conventional method. Methods: The standard technique for the electrophysiological study done to induce tachycardia. Three or four catheters were used. Atrial or ventricular programmed stimulation used to induce the tachycardia. Differentiation of the atrioventricular nodal reentry from atrial tachycardia and atrioventricular tachycardia done by ventricular entrainment. The dry ablation catheter of 4 mm tip used to modify the slow pathway. The appearance of junctional rhythm was a sign of the effective application of the radiofrequency application. The success of ablation was indicated by a failure to induce the tachycardia with repeated programmed stimulation. Results: Seventy patients with atrioventricular nodal reentry tachycardia were selected from total supraventricular tachycardia cases of 106 patients referred to the catheter lab for radiofrequency ablation. In 85% of the cases atrial programmed stimulation were used to induce the tachycardia and ventricular programmed stimulation and in 15% of the cases. Acute success rate was seen in 68 patients (97%). Conclusion: Catheter radiofrequency ablation is becoming technically easy, safe, and reliable as first line treatment in the majority of patients with atrioventricular reentry tachycardia.

Multicenter Study to Standardize and Evaluate the Efficacy of Radiofrequency Ablation Therapy for Early Breast Cancer (RAFAELO Study)

Journal of the American College of Surgeons 229(4):p e6-e7, October 2019. | DOI: 10.1016/j.jamcollsurg.2019.08.881

RFA experiences, indications and clinical outcomes.

Early-stage breast cancer is increasingly detected by screening mammography, and we aim to establish radiofrequency ablation therapy (RFA) as a minimally invasive, cost-efficient, and cosmetically acceptable local treatment. Although there were many studies on resection after RFA, none of them provided sufficient evidence to support RFA as a standard therapy for breast cancer. In our Phase I study, localized tumors with a maximum diameter of 2cm, preoperatively diagnosed by imaging and histopathology, were treated with RFA. A 90% complete ablation rate was confirmed histopathologically. Our phase II multicenter study of RFA without resection for early breast cancer will evaluate the long-term safety and efficacy of RFA as well as its cosmetic results, which are a perceived advantage of this technique. We started a phase III multicenter study to demonstrate the non-inferiority of RFA compared with standard treatment (breast-conserving surgery) in terms of ipsilateral breast tumor recurrence (IBTR) rate, which is the best index of local control. To standardize RFA for breast cancer, the results of our multicenter study, Radiofrequency Ablation Therapy for Early Breast Cancer as Local Therapy (the RAFAELO study) that began in 2013, are eagerly awaited.

Abstract OT2-03-01: Multicenter study to standardize and evaluate the efficacy of radiofrequency ablation therapy for early breast cancer (RAFAELO study)

Abstract Background: Early-stage breast cancer is increasingly detected by screening mammography, and we aim to establish radiofrequency ablation therapy (RFA) as a minimally invasive, cost-efficient, and cosmetically acceptable local treatment. In our Phase I study, localized tumors with a maximum diameter of 2 cm, preoperatively diagnosed by imaging and histopathology, were treated with RFA. A 90% complete ablation rate was confirmed histopathologically. Our phase II multicenter study of RFA without resection for early breast cancer will evaluate the long-term safety and efficacy of RFA as well as its cosmetic results, which are a perceived advantage of this technique. Trial design: This study is a Phase III, single-arm, multicenter study being conducted with the participation of 11 hospitals. In our experimental therapy, a radiofrequency electrode needle is inserted through the skin into the breast lesion under imaging guidance, followed by thermal ablation with radiofrequency waves. RFA will be conducted under general anesthesia. The Cool-tip™ RF Ablation Single Electrode Kit (Medtronic, CO, USA) will be used to standardize the evaluation of the ablation effect. After RFA, all patients will receive radiotherapy and systemic therapy according to the ER, HER2, tumor grade, and lymph node status of the primary tumor. Residual lesions after RFA will be assessed approximately 3 months after radiotherapy using imaging and pathological studies. All patients will undergo vacuum-assisted biopsy regardless of imaging results. If specimens show viable tumor tissue, additional excision will be performed. Follow-up evaluation for residual tumor, including clinical breast examination and diagnostic imaging (ultrasound, MRI, and mammography), will be performed yearly after RFA. This trial has been registered at the UMIN Clinical Trials Registry as UMIN000012429. Eligibility criteria: Early breast cancer patients, who are lack of prior treatment for breast cancer and histologically confirmed ductal carcinoma with a single localized tumor of 1.5 cm or less in the greatest dimension and clinically node negative on preoperative imaging. Specific Aims: The primary endpoint is 5-year ipsilateral breast tumor recurrence(IBTR) rate, and the secondary endpoints are residual lesion rate, overall survival, DFS, and adverse events of RFA. Statistical methods: The IBTR rate should be similar to that with standard treatment (BCS). However, the IBTR after RFA alone may be higher by up to 10% than in the NSABP-B06 study; therefore the 5-year IBTR rate is estimated to be 6.3%. We calculated the required sample size based on the following assumptions: a clinically acceptable 5-year local recurrence-free survival rate of 90%, a one-sided significance level of 5% (alpha = 0.1, 2-sided), and power of 80% (beta = 0.2). Taking into account a drop-out rate of 10%, approximately 372 patients will be enrolled in the study. Present accrual and target accrual: The trial was activated in August 2013, with a total of 372 patients enrolled by the end of June 2018. Citation Format: Kinosita T, Takahashi M, Fujisawa T, Yamamoto N, Doihara H, Ohtani S, Futamura M, Takahashi M, Aogi K, Hojo T, Yoshida M, Shiino S, Tsuda H. Multicenter study to standardize and evaluate the efficacy of radiofrequency ablation therapy for early breast cancer (RAFAELO study) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-03-01.

The Place of Elastography in Evaluating the Efficacy of Radiofrequency Ablation of Thyroid Nodules

The usage of radiofrequency ablation (RFA) therapy and elastography to treat thyroid nodules has been increasing recently. Elastography specifically measures the stiffness of tissue using ultrasonography (US). The aim of the present study was to evaluate the relationship between the elastography values of thyroid nodules and the efficacy of RFA therapy. Ultrasonography was performed on 49 patients who had a thyroid nodule with a diameter of 1 cm or greater before RFA therapy. The RFA was performed under local anesthesia, and elastography was used to measure the stiffness of the normal thyroid tissue, sternocleidomastoid muscle (SCM) and thyroid nodules three months after RFA. The nodule diameter significantly decreased three months after RFA (P < 0.05). According to a cross-evaluation of the mean elastography rates, the thyroid/SCM and nodule/thyroid elastography rates had an inverse relationship (P: 0.009). However, the thyroid/SCM elastography rates and nodule/SCM elastography rates (P: 0.022) and the thyroid/SCM elastography rates and the rates of reduction (%) of the nodule diameter before and three months after RFA (P: 0.016) had positive relationships. In conclusion, RFA therapy is more effective in patients with thyroid nodules if there are high thyroid tissue/SCM rates in elastography.

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.

Colorectal Liver Metastases

Although radiofrequency ablation (RFA) is increasingly an accepted option for patients with colorectal liver metastases, patients treated with resection vs RFA may have different tumor biology profiles, which might confound the relationship between choice of liver-directed therapy and outcome. Retrospective review of a prospectively collected database. Major hepatobiliary center. Between January 1, 1999, and August 30, 2006, 258 patients with colorectal liver metastases underwent hepatic resection with or without RFA. Evaluation of outcome following resection alone, combined resection-RFA, and RFA alone using 3 statistical methods (paired-match control, Cox proportional hazards multivariate model, and propensity index) to identify and adjust for potential confounding variables. The median number of hepatic lesions was 2, and the median size of the largest lesion was 3.0 cm. One hundred ninety-two patients (74.4%) underwent resection alone, 55 patients (21.3%) underwent resection-RFA, and 11 patients (4.3%) underwent RFA alone. Patients who underwent resection-RFA had significantly increased risk of extrahepatic failure at 1 year vs patients who underwent resection alone or RFA alone (P < .05). On matched control and multivariate analyses, patients who underwent RFA with or without resection had significantly worse disease-free and overall survival than patients who underwent resection alone. Propensity score methods revealed that the aggregate distribution of clinical risk factors for resection-RFA was markedly different from that for resection alone. This suggested a lack of comparability to allow for statistical comparisons in the assessment of causal inferences regarding the efficacy of RFA therapy. Although results of matched control and multivariate analyses suggested that RFA with or without resection was associated with worse outcome, propensity score methods revealed that the resection-RFA and resection-alone groups were different with regard to baseline tumor and treatment-related factors, making causal inferences about the efficacy of RFA unreliable.

Radiofrequency ablation therapy in idiopathic left ventricular tachycardia with no obvious structural heart disease.

The feasibility and efficacy of radiofrequency ablation therapy in idiopathic left ventricular tachycardia has not been assessed in a large group of patients. Twenty consecutive patients with idiopathic left ventricular tachycardia and without structural heart disease underwent electrophysiological study, pharmacological interventions with administration of verapamil and adenosine, and radiofrequency ablation therapy. There were 17 men and 3 women with a mean age of 28 +/- 8 years. The QRS configuration during tachycardia was of right bundle branch block and superior axis in 13 patients, indeterminate axis in 6 patients, and right axis in 1 patient. The tachycardia was electrically inducible and responsive to verapamil but not to adenosine. Thirteen patients demonstrated entrainment. Activation and pace-mapping studies disclosed that the tachycardia originated from the inferior apical septum in 15 patients, the midseptum in 4 patients, and the anterior lateral wall of the left ventricle in 1 patient. Radiofrequency ablation was successful in 17 of the 20 patients (85%). The successful ablation sites were characterized by an endocardial activation time 30 milliseconds earlier than the onset of QRS during tachycardia and by a pace-mapping QRS similar to or closely resembling the tachycardia. All patients displayed sharp spikes preceding the local ventricular electrogram at the ablation site. However, these sharp spikes also were noted in 15 control patients and were not specific for this tachycardia; they persisted after ablation. There were no complications. A follow-up of 7 +/- 8 months in the 17 successfully ablated patients showed no symptomatic tachyarrhythmias without medications. Six patients underwent repeat electrophysiological study, and no induction of tachycardia was revealed. Radiofrequency ablation therapy is effective and safe in patients with idiopathic left ventricular tachycardia. It should be considered as the primary therapeutic modality in these patients.