Percutaneous Ablation Techniques Research Articles

Advances in Image-Guided Ablation Therapies for Solid Tumors

Image-guided solid tumor ablation methods have significantly advanced in their capability to target primary and metastatic tumors. These techniques involve noninvasive or percutaneous insertion of applicators to induce thermal, electrochemical, or mechanical stress on malignant tissue to cause tissue destruction and apoptosis of the tumor margins. Ablation offers substantially lower risks compared to traditional methods. Benefits include shorter recovery periods, reduced bleeding, and greater preservation of organ parenchyma compared to surgical intervention. Due to the reduced morbidity and mortality, image-guided tumor ablation offers new opportunities for treatment in cancer patients who are not candidates for resection. Currently, image-guided ablation techniques are utilized for treating primary and metastatic tumors in various organs with both curative and palliative intent, including the liver, pancreas, kidneys, thyroid, parathyroid, prostate, lung, breast, bone, and soft tissue. The invention of new equipment and techniques is expanding the criteria of eligible patients for therapy, as now larger and more high-risk tumors near critical structures can be ablated. This article provides an overview of the different imaging modalities, noninvasive, and percutaneous ablation techniques available and discusses their applications and associated complications across various organs.

Radiofrequency ablation versus microwave ablation for hepatocellular carcinoma with cirrhosis: a propensity score analysis.

Radiofrequency ablation (RFA) and microwave ablation (MWA) are the most frequently used percutaneous ablation techniques for the treatment of liver cancer. The aim of our study was to identify the ablation method that had a better long-term prognosis for patients with cirrhotic hepatocellular carcinoma (HCC). This retrospective study consisted of HCC patients with cirrhosis who underwent RFA and MWA between January 2014 to December 2021 at Beijing You'an Hospital. Patients were divided into two groups according to the therapeutic approaches: the RFA group and the MWA group. The prognosis was compared before and after 1:1 propensity score matching (PSM). A total of 800 HCC patients with cirrhosis who received interventional treatment from January 2014 to December 2021 were prospectively enrolled. After PSM, there were 268 patients in each of the RFA and MWA groups. The statistically significant differences in recurrence-free survival (RFS) and overall survival (OS) between RFA and MWA groups can be observed, both before and after PSM. Besides, 1-, 3-year RFS, and 5-year OS rates were higher in those the RFA group than in the MWA group. Age, tumor size, gamma glutamyl transferase (GGT), and hepatitis B surface antigen (HBsAg) were independent risk factors for RFS. Child-Pugh, lymphocyte (Lym), GGT, and treatment modality were independent risk factors for OS. For patients with HCC associated with cirrhosis, RFA can provide a better prognosis than MWA, with lower recurrence and mortality rate.

Magnetic resonance-guided focused ultrasound versus percutaneous thermal ablation in local control of bone oligometastases: a systematic review and meta-analysis.

The percutaneous thermal ablation techniques (pTA) are radiofrequency ablation, cryoablation, and microwave ablation, suitable for the treatment of bone oligometastases. Magnetic resonance-guided focused ultrasound (MRgFUS) is a noninvasive ablation technique. To compare the effectiveness and safety of MRgFUS and pTA for treating bone oligometastases and their complications. Studies were selected with a PICO/PRISMA protocol: pTA or MRgFUS in patients with bone oligometastases; non-exclusive curative treatment. Exclusion criteria were: primary bone tumor; concurrent radiation therapy; palliative therapy; and absence of imaging at follow-up. PubMed, BioMed Central, and Scopus were searched. The modified Newcastle-Ottawa Scale assessed articles quality. For each treatment (pTA and MRgFUS), we conducted two separate random-effects meta-analyses to estimate the pooled effectiveness and safety. The effectiveness was assessed by combining the proportions of treated lesions achieving local tumor control (LTC); the safety by combining the complications rates of treated patients. Meta-regression analyses were performed to identify any outcome predictor. A total of 24 articles were included. Pooled LTC rate for MRgFUS was 84% (N = 7, 95% CI 66-97%, I2 = 74.7%) compared to 65% of pTA (N = 17, 95% CI 51-78%, I2 = 89.3%). Pooled complications rate was similar, respectively, 13% (95% CI 1-32%, I2 = 81.0%) for MRgFUS and 12% (95% CI 8-18%, I2 = 39.9%) for pTA, but major complications were recorded with pTA only. The meta-regression analyses, including technique type, study design, tumor, and follow-up, found no significant predictors. The effectiveness and safety of the two techniques were found comparable, even though MRgFUS is a noninvasive treatment that did not cause any major complication. Limited data availability on MRgFUS and the lack of direct comparisons with pTA may affect these findings. MRgFUS can be a valid, safe, and noninvasive treatment for bone oligometastases. Direct comparison studies are needed to confirm its promising benefits.

MR Imaging‐Guided High Intensity Focused Ultrasound in the Treatment of Neurologic Disease: Current Applications and Future Directions

MR imaging‐guided focused ultrasound is a revolutionary noninvasive technique with a wide breadth of clinical potential. MR imaging‐guided focused ultrasound uses focused ultrasound energy delivered transcranially to treat a variety of neurologic disease processes. High-intensity focused ultrasound creates sufficient acoustic energy for targeted noninvasive thermal ablation of intracranial soft tissues, with sharply marginated treatment zones overall superior to the established percutaneous ablation techniques. The use of concurrent MR imaging allows highly accurate spatial and thermal guidance, with fine anatomic detail, high soft-tissue contrast, and real-time monitoring of the treatment zone. Here we review the current established applications of MR imaging‐guided focused ultrasound in the treatment of neurologic disease and the relevant anatomic targets for each discussed disease entity, with a focus on essential tremor, Parkinson disease, and neuropathic pain, along with investigative applications and future directions related to this innovative technology.Learning Objective: To provide a comprehensive review of the existing literature on current neurologic applications of MR imaging‐guided high-intensity focused ultrasound and the relevant anatomic targets for each disease entity, discuss investigative applications and future directions for MR imaging‐guided high-intensity focused ultrasound, and increase awareness among providers to promote safe informed use of this relatively newer technology

Ultrasonography-guided radiofrequency ablation of vascular malformations-The moving shot technique.

To describe a novel ultrasound-guided technique for percutaneous radiofrequency ablation of vascular malformations-the "moving shot technique." Preliminary observational cohort study, conducted from June 1, 2019, to January 31, 2021, including all consecutive patients diagnosed with vascular malformations who were treated with ultrasound-guided radiofrequency ablation using the moving shot technique. Only patients who had undergone at least one unsuccessful previous treatment were included (sclerotherapy with ethanol/aethoxysklerol or embolization/surgery). Eight patients with a median age of 22 years (interquartile range, 13-31) were included. Patients had different vascular malformations consisting of 1 arteriovenous malformation, 4 venous malformations, and 1 each a mixed venous-lymphatic malformation, a glomuvenous malformation and a FAVA (fibroadipose vascular anomaly). Malformations were located at the limbs in 5 patients (62.5%), the subcutaneous/intramuscular tissue of the body in 2 patients (25%) and at the chin in 1 patient (12.5%). Clinical symptoms were pain in 8 patients (100%), swelling in 6 patients (75%), and partial immobility in 4 patients (50%). All patients showed an improvement of clinical symptoms after treatment with 7 (87.5%) being completely asymptomatic and 1 (12.5%) showing improvement of immobility and pain. No procedural complications, such as nerve damage or skin burns occurred. The moving shot technique using ultrasonography-guided radiofrequency ablation is a promising technique for the interventional treatment of vascular malformations and should be validated in multicenter-approaches.

Crioablación de tumores de mama

Cryoablation is a percutaneous thermal ablation technique developed to destroy focal groups of cells using extreme cold. It is an outpatient and image-guided procedure, performed under local anaesthesia, with typically short recovery times and good outcomes. Percutaneous cryoablation has good success rates for treating breast fibroadenomas. It is used in cases of malignant tumours mainly when a patient refuses surgery or is not considered to be a suitable candidate. Some studies indicate that cryoablation could be as effective and safe as lumpectomy in cases of low-risk early-stage breast cancer. Moreover, some studies have reported a regression of metastatic foci after ablation of a primary tumour thanks to an anti-tumour immune response stimulated by cryoablation. This article describes the technique and its indications with regards to breast tumours according to the existing literature.

Hepatic Arteriography and C-Arm CT-Guided Ablation (HepACAGA) to Improve Tumor Visualization, Navigation and Margin Confirmation in Percutaneous Liver Tumor Ablation

PurposeWe present a technique that combines Hepatic Arteriography with C-arm CT-Guided Ablation (HepACAGA) to improve tumor visualization, navigation and margin confirmation for percutaneous ablation of liver tumors.Materials and MethodsAll consecutive patients scheduled for HepACAGA between April 20th, 2021, and November 2nd, 2021, were included in this retrospective, cohort study. HepACAGA was performed in an angiography-suite under general anesthesia. The hepatic artery was catheterized for selective contrast injection. C-arm CT and guidance software were then used to visualize the tumor and the microwave antenna was inserted during apnea. Pre- and post-ablation C-arm CTs were performed and ablation margins assessed. Technical success, antenna placement deviation, number of repositions, tumor recurrence, and safety were evaluated. Technical success was defined as a tumor that was ablated according to the HepACAGA technique.ResultsA total of 21 patients (28 tumors) were included. The main tumor type was colorectal cancer liver metastases (11/21, 52%), followed by hepatocellular carcinoma (7/21, 33%), neuroendocrine tumor metastases (1/21, 5%), and other tumor types (2/21, 10%). The technical success rate was 93% (26/28 tumors) with two small hypovascular lesions unable to be identified. A single microwave antenna was used in all patients. The median antenna placement deviation was 1 mm (range 0–6 mm). At a median follow-up time of 16 months (range 5–22 months), there was no tumor recurrence in any patient. Safety analysis showed a complication rate of 5% grade 2 and 5% grade 3.ConclusionHepACAGA was demonstrated to be a safe and effective percutaneous ablation technique, without any local tumor recurrence in this study.Graphic

Role of Percutaneous Ablation in the Management of Intrahepatic Cholangiocarcinoma.

Cholangiocarcinoma (CCA) is an invasive cancer accounting for <1% of all cancers and 10-15% of primary liver cancers. Intrahepatic CCA (iCCA) is associated with poor survival rates and high post-surgical recurrence rates whilst most diagnosed patients are not surgical candidates. There is a growing literature suggesting percutaneous ablative techniques for the management of patients with iCCA measuring ≤3 cm with contraindications to surgery as well as for recurrent or residual tumors aiming to provide local cancer treatment and control. Most used ablative therapies for iCCA include radiofrequency and microwave ablation with irreversible electroporation, cryoablation and reversible electroporation (electrochemotherapy) being less commonly encountered techniques. Due to the infiltrative margins of the lesion, there is a need for larger safety margins and ablation zone; multi-apparatus ablation or other variations of the technique such as balloon-assisted approaches can be utilized aiming to increase size of the zone of necrosis. The present review paper focuses upon the current role of percutaneous ablative techniques for the therapeutic management of iCCA. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of iCCA, including local control and survival rates.

CT-guided local ablative interventions

Applicator-based local ablations under computed tomography (CT) guidance for the treatment of malignant tumors have found their way into clinical routine. The basic principles of the different ablation technologies and their specific clinical field of application are described. Acomprehensive literature review regarding applicator-based ablation techniques was carried out. Radiofrequency (RFA) and microwave ablation (MWA) represent two image-guided hyperthermal treatment modalities that have been established for the treatment of primary and secondary liver malignancies. In addition, both techniques are also applied for local ablative therapy of lung- and kidney tumors. Cryoablation is mainly used for the local ablation of T1 kidney cancer and due to its intrinsic analgetic characteristics for application in the musculoskeletal system. Nonresectable pancreatic tumors and centrally located liver malignancies can be treated with irreversible electroporation. This nonthermal ablation modality preserves the structure of the extracellular matrix including blood vessels and ducts. Technical advancements in the field of CT-guided interventions include the use of robotics, different tracking and navigation technologies and the use of augmented reality with the goal to achieve higher precision, shorter intervention time and thereby reduce radiation exposure. Percutaneous ablation techniques under CT guidance are an essential part of interventional radiology and they are suited for local treatment of malignancies in most organ systems.

Is Continuous Wound Infiltration a Better Option for Postoperative Pain Management after Open Nephrectomy Compared to Thoracic Epidural Analgesia?

Despite increasingly advanced minimally invasive percutaneous ablation techniques, surgery remains the only evidence-based therapy in curative intent for larger (>3-4 cm) renal tumors. Although minimally invasive surgery using (robotic-assisted) laparoscopic or retroperitoneoscopic approaches has gained popularity, open nephrectomy (ON) is still performed in 25% of cases, especially in tumors with central localization (partial ON) or large tumors with/without cava thrombus (total ON). As postoperative pain is one of the drawbacks of ON, our study aims to assess recovery and post-operative pain management using continuous wound infiltration (CWI) compared to thoracic epidural analgesia (TEA). Since 2012, all patients undergoing ON at our tertiary cancer center at CHUV have been included in our prospective ERAS® (enhanced recovery after surgery) registry that is centrally stored in ERAS® Interactive Audit System (EIAS) secured server. This study represents an analysis of all patients operated on with partial or total ON at our center between 2012 and 2022. An additional analysis was performed for the estimations of the total cost of CWI and TEA, based on the diagnosis-related group method. 92 patients were included and analyzed in this analysis (n = 64 (70%) with CWI; n = 28 (30%) with TEA). Adequate oral pain control was earlier achieved in the CWI group compared to the TEA group (median 3 vs. 4 days; p = 0.001), whereas immediate postoperative pain relief was better in the TEA group (p = 0.002). Consequently, opioid use was higher in the CWI group (p = 0.004). Still, reported nausea was lower in the CWI group (p = 0.002). Median time to bowel recovery was similar in both groups (p = 0.03). A shorter LOS (0.5 days) was observed in patients managed with CWI, although this was not statistically significant (p = 0.06). The use of CWI has reduced total hospital costs by nearly 40%. TEA has better results in terms of postoperative pain management compared to CWI following ON. However, CWI is better tolerated, and causes less nausea and earlier recovery, which leads to a shorter length of stay. Given its simplicity and cost-effectiveness, CWI should be encouraged for ON.

Abstract No. 158 Characterizing the Anti-Tumor Immune Response to IRE vs Thermal Ablation Therapy in an Immunocompetent Oncopig Model of Hepatocellular Carcinoma

Immunotherapies for cancer treatment are designed to mobilize a patient’s own immune system against their malignancy locally and systemically. Percutaneous ablation techniques have the potential to work in conjunction with modern immunotherapies by priming the patient’s own lymphocytes to attack previously untreated cancer cells. This phenomenon, known as the abscopal effect, has garnered interest because of the potential for locoregional therapies to induce local and systemic anti-tumor effects and shrinkage of distant tumors (Fionda, 2020). The goal of this study is to evaluate the anti-tumor immune response to irreversible electroporation (IRE) compared with microwave (MWA) and cryoablation in an immunocompetent Oncopig liver tumor model of hepatocellular carcinoma. In-situ liver tumors were induced in a transgenic immunocompetent porcine liver model (2-4 tumors in each liver) with Cre-recombinase induced TP53 and KRAS mutations (Oncopig). Oncopigs were separated into three treatment groups (n = 2), each undergoing either MWA, cryoablation or IRE treatment of a single liver tumor under US or CT guidance. Pre-, immediate post- and 1-week post ablation imaging was performed to evaluate treated and non-treated tumor growth. At each time point, venous blood was also drawn and assayed for critical cytokines related to anti- or pro-tumor immune response. Systemic cytokine levels were correlated to targeted and off-targeted tumor volumes after each time point. Liver tumors were induced at an 83.3% (20/24) success rate. Treated tumors decreased by an average 7% in volume across all treatment modalities on 1-week follow-up imaging. Off-target tumors increased by volume by 71.7% with IRE, 13.6% with MWA and 1.4% with cryoablation. On 1-week blood samples, IRE treated pigs demonstrated lower circulating concentrations of pro-inflammatory IL-2 cytokines when compared with cryoablation (10.9 vs 40.7 pg/mL; P = 0.051). There was no difference in IL-2 levels between MWA and cryoablation-treated pigs (40.7 vs 42.4 pg/mL; P = 0.97). The pro- and anti-tumor immune response is dependent on the type of ablation modality. IRE had the lowest levels of inflammatory marker IL-2 and the lowest degree of tumor control in off target tumors at the one-week time point. Modulating inflammatory pathways via these cytokines after IRE may potentially play a role in amplifying the abscopal effect in liver tumors.

Abstract No. 132 Trends in percutaneous ablation procedures among Medicare patients from 2010-2018: an analysis of procedure volume, specialty involvement, and reimbursement rates

The use of percutaneous ablative techniques in the treatment of a variety of cancers and benign tumors is well documented with research supporting effective outcomes in appropriately selected patients. The following provides an overview of ablations performed for Medicare Beneficiaries by organ system.

Interventional Radiology's Osteoid Osteoma Management: Percutaneous Thermal Ablation.

Osteoid osteoma (OO) is one of the most common benign bone tumors with specific clinical and radiological characteristics. Analgesic therapy and surgical treatment have been considered the only therapy for a long time. Recently, safe and effective new therapeutic options have been introduced, among which percutaneous thermal ablation techniques. This review aims to describe the recent updates in the field of percutaneous thermal ablation techniques in the treatment of OO, assessing the outcomes in terms of efficacy, complications, and recurrence rate.

A New Tool to Predict Success Rate of Percutaneous Ablation for HCC: The Ablation Difficulty Score

Introduction: Percutaneous local ablative techniques (LAT), such radiofrequency ablation (RFA), results successful options for treating early HCCs. However, persistence of disease and local tumor progression (LTP) occurs. This study wants identify the factors related to ablation failure and propose a score for improving patient selection and treatment allocation.

Nonsurgical Management of Thyroid Nodules: The Role of Ablative Therapies.

ContextAfter a thorough evaluation most thyroid nodules are deemed of no clinical consequence and can be observed. However, when they are compressive, toxic, or involved by papillary thyroid carcinoma surgery or radioactive iodine (RAI) (if toxic) are the treatments of choice. Both interventions can lead to hypothyroidism and other adverse outcomes (eg, scar, dysphonia, logistical limitation with RAI). Active surveillance might be used for papillary thyroid microcarcinoma (PTMC) initially, but anxiety leads many cases to surgery later. Several ablative therapies have thus evolved over the last few years aimed at treating these nodules while avoiding described risks.CasesWe present 4 cases of thyroid lesions causing concern (compressive symptoms, thyrotoxicosis, anxiety with active surveillance of PTMC). The common denominator is patients’ attempt to preserve thyroid function, bringing into focus percutaneous ethanol injection (PEI) and thermal ablation techniques (radiofrequency ablation [RFA] being the most common). We discuss the evidence supporting these approaches and compare them with standard therapy, where evidence exists. We discuss additional considerations for the utilization of these therapies, their side-effects, and conclude with a simplified description of how these procedures are performed.ConclusionThermal ablation, particularly RFA, is becoming an attractive option for managing a subgroup of solid thyroid nodules, while PEI has a role in managing thyroid cysts and a select group of PTMC. Their role in the algorithm of thyroid nodule management is still being refined and technical expertise will be essential to reproduce the reported results into everyday practice.

Long-Term Follow-Up of Single-Fiber Multiple Low-Intensity Energy Laser Ablation Technique of Benign Thyroid Nodules.

AimThe short-term and long-term efficacy of different thermal percutaneous ablation techniques remains a topical issue. Our group implemented percutaneous laser ablation (LA), a moving-shot technique to increase efficiency and reduce costs and variability of LA by applying multiple lower-intensity energy illuminations (MLIEI) covering the nodular volume (V) through changes in position of a single laser fiber within the thyroid nodule. The aim of the present study was to evaluate the efficacy of the single-fiber LA-MLIEI during a 5-year follow-up and to identify possible predictors of the final outcome.Methods Prospective study: Thirty outpatients (23 women and seven men) with benign symptomatic thyroid nodules were assigned to single-fiber LA-MLIEI, between 2012 and 2015. A single LA session was performed under real-time ultrasound (US) guidance using a 1,064-nm continuous-wave laser at 3 W. A 400-µm optical fiber was inserted through a 21-gauge needle, and 3–10 illuminations were performed per nodule, administering between 400 and 850 J/illumination. The total administered energy was calculated on the initial V of the nodule and the estimated ablation area. US evaluation was performed after LA-MLIEI at 1 week and 1, 3, 6, and 12 months and after that annually up to 5 years. Clinical symptoms, laboratory thyroid function during follow-up, and acute and chronic complications of treatment were registered.ResultsOn follow-up, 67% (n: 20) were responders to single-fiber LA-MLIEI, while 33% (n: 10) were non-responders. The responder group initiated V reduction (ΔV) at 1 month, with remission of symptoms, and presented a 50% ΔV at 3 months of treatment; the maximum response was achieved at 24 months and remained stable until the end of the study. The non-responder group presented a ΔV of less than 50% at 12 months; though a tendency to >50% ΔV was observed at 24–36 months, there was subsequent regrowth, and 40% of this group required surgery. ΔV was positively correlated with the total administered energy/V (J/V) and inversely with nodule V. No severe adverse effects were observed. Thyroid function remained normal in all patients. Remission of symptoms occurred rapidly after 1 month.ConclusionsLA with multiple fractional discharges employing a single fiber in a unique session is a safe and inexpensive technique that allows rapid reduction of thyroid nodules, with a stable response up to 5 years, similarly to what has been reported with the conventional LA. Total nodule volume appears as a predictive factor of the reduction.

Strategies to improve sorafenib efficacy during image-guided treatment of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third most frequent source of deaths associated with cancer after lung cancer in the world despite recent innovative treatment techniques. Liver transplantation, hepatic resection, and percutaneous ablation techniques hold great promise as potentially curative treatments for patients at early stages. Nevertheless, most of the patients are not suitable for these curative treatments due to their advanced disease stages at the time of diagnosis. Food and Drug Administration (FDA) approved tyrosine kinase inhibitor, sorafenib is a standard therapy for advanced-stage HCC patients which extends overall survival for several months. However, its therapeutic efficacy is restricted by adverse events and drug resistance which limits the number of patients benefiting from this systemic chemotherapeutic drug. During the last decade, novel approaches including but not limited to immunotherapies, ablation methods, and chemotherapeutic drugs were proposed to enhance sensitivity to sorafenib, improve therapeutic efficacy, and prohibit adverse events through novel delivery routes, utilization of nanoparticle carriers, and combination with other therapeutic agents. However, studies are still being conducted to optimize the efficiency of sorafenib and reduce its adverse events. In this review paper, we examine research studies evaluating novel delivery methods to reduce drug-related cytotoxicity to improve patient tolerance to sorafenib and its therapeutic efficacy in patients with HCC. Moreover, therapeutic approaches with the synergistic potential to combine with sorafenib are briefly summarized.

Alternative methods for local ablation-interventional pulmonology: a narrative review.

ObjectiveTo discuss and summarise the background and recent advances in the approach to bronchoscopic ablative therapies for lung cancer, focusing on focal parenchymal lesions.BackgroundThis series focusses on the challenges highlighted by increasing recognition of the prognostically more favourable oligometastatic disease rather than the more frequent, but prognostically poor, high tumour burden metastatic disease. While surgery, stereotactic body radiation therapy (SBRT), and trans-thoracic percutaneous ablative techniques such as microwave (MWA) and radiofrequency ablation (RFA) are well recognised options for selected cases of pulmonary oligometastasis, bronchoscopic approaches to pulmonary tumour ablation are becoming realistic alternatives. An underlying tenet driving research and implementation in this domain is that percutaneous ablative techniques are obliged to traverse the pleura leading to a high rate of pneumothorax, and risks also goes up for peri-vascular lesions. Historically low yield bronchoscopic targeting of isolated peripheral tumors have significantly improved by incorporating multi-modality high resolution imaging and processing, including navigation planning and real-time image guidances (ultrasound, electromagnetic navigation, cone-beam CT). Combining advanced image guidance with ablative technology adaptations for bronchoscopic delivery opens up the options for high dose local ablative therapies that may reduce transthoracic complications and provide palliative to curative options for limited stage primary and oligometastatic diseases.MethodsWe conduct a narrative review of the literature summarizing the history of bronchoscopic tumor ablation approaches, technical details including biologic rational for their uses, and current evidence for each modality, as well as investigations into future applications. Because of the relative paucity of prospective studies, we have been very inclusive in our inclusion of experiences from the published clinical databases.ConclusionsWhilst surgical resection and SBRT remain the current mainstay of curative therapies for peripheral cancers, in the foreseeable future, developments and further research will see bronchoscopic ablative therapies become viable lung sparing alternatives in those deemed suitable. The future is bright.

Image-Guided Percutaneous Ablation of Adrenal Metastases: A Meta-Analysis of Efficacy and Safety

PurposeTo evaluate the efficacy and safety of percutaneous ablation of adrenal metastases through a meta-analysis of various image-guided percutaneous ablation techniques. Materials and MethodsA comprehensive literature search of PubMed and Embase databases was performed for studies evaluating the efficacy and/or safety of image-guided percutaneous ablation of adrenal metastases. A total of 37 studies published between 2009 and 2020 were analyzed, comprising a sample size of 959 patients. Proportion estimates of overall survival, local control, and toxicity were analyzed in a pooled meta-analysis. The pooled prevalence of adverse events after ablation was calculated based on common terminology criteria for adverse events (CTCAE) grading. ResultsOf the 959 included patients, 320 (33.3%) underwent radiofrequency ablation, 72 (7.5%) microwave ablation, 95 (9.9%) cryoablation, and 46 (4.8%) ethanol injections for treatment of adrenal metastases. The remaining 426 (44.4%) patients were from studies involving a mixture of the 4 listed percutaneous ablation techniques. The pooled 1-year local control rate was 80% (95% confidence interval [CI], 76%–83%). The pooled 1-year overall survival rate was 77% (95% CI, 70%–83%). The overall rate of severe adverse events after ablation (CTCAE grade 3 or higher) was 16.1%. The overall rate of low-grade adverse events after ablation (CTCAE grade 2 or lower) was 32.6%. Approximately 21.9% (n = 203) of patients experienced intraprocedural hypertensive crises, the majority of which were reversed with antihypertensive medications. ConclusionsThis study demonstrates that image-guided percutaneous ablation can be effective in achieving acceptable short- to mid-term local tumor control and overall survival with a moderate safety profile.

Current Practice of Percutaneous Ablation Technologies for Thyroid Nodules 2020

Thyroid nodules are commonly diagnosed in the general population. Though the majority of them are benign and followed clinically once detected, if compressive symptoms arise or malignancy is diagnosed, then surgical excision is considered the standard treatment. As surgery is associated with various post-operative complications, newer less invasive techniques have gained popularity. This article presents the various percutaneous ablation techniques that are currently being used for thyroid nodules. In recent years, several studies largely from Asian and Europe institutions have shown promising results with the use of radiofrequency ablation (RFA), ethanol ablation (EA), and laser ablation (LA) for thyroid nodules. These techniques are gaining more acceptance worldwide as an alternative to surgery. Comparatively newer techniques such as microwave ablation (MWA) and high-intensity focus ultrasound (HIFU) are also available but there is little evidence about their efficacy. Percutaneous ablation techniques with a promising safety profile can be an effective alternative to traditional surgical methods for the management of carefully selected thyroid nodules. However, large-scale randomized control trials are needed to establish the efficacy and safety of these techniques in the North American population.