From Simulation to Reality: A Comprehensive Study on the Efficacy of a Rotating Monopolar and Bipolar Radiofrequency System through In-Silico Modeling and Pre-Clinical and Clinical Validation

Background: Skin aging is an unavoidable process aggravated by environmental agents. Among other energy devices, non-invasive radiofrequency (RF) technology is widely used for skin tightening and body contouring as it is simpler and more affordable than other technologies that also minimize pain and side-effects. However, most of the current RF devices do not provide automatic skin temperature control and it is difficult to achieve controlled, deep, and harmless thermal increase, so treatment performance and safety is dependent on the operator’s movements and expertise. Objective: To show the potential of numerical simulations for optimizing the design of monopolar and bipolar RF electrodes that are capable of providing homogeneous, deep and controlled heating. Materials and methods: In-silico models were developed and analyzed using Comsol Multiphysics software to simulate the RF effect produced in tissue by rotating monopolar and bipolar electrodes with different geometries from the Sculpt & Shape RF device (Sinclair, Spain), operating at frequencies of 0.5 and 1 MHz. Ex-vivo and in-vivo proof-of-concept tests were carried out to validate the simulations. Finally, treatments were performed on 16 subjects and a total of 78 body areas to assess the clinical results generated by the RF electrodes for skin tightening and body contouring. Results: In-silico studies emulated the superficial and deep dispersion of heat due to the release of RF energy into human skin tissue. The rotating electrodes (monopolar and bipolar) and the selected RF frequency (0.5 and 1 MHz) determined the homogeneity of the thermal distribution, the penetration depth (between 4.37 mm and 25.0 mm) and the heating dynamics (between 30 and 100 seconds to reach the target skin temperature), which were confirmed by ex-vivo and in-vivo tests. In addition, real treatments on facial and body areas using skin temperatures of between 43˚C and 44˚C showed consistent results with good clinical efficacy for skin tightening, circumference reduction and cellulite reduction, with no adverse effects and high subject satisfaction. Conclusions: New monopolar and bipolar RF electrodes with rotating technology have been designed and optimized using numerical simulations. The use of in-silico studies and accurate models that reproduce the thermal behavior of human biological tissues can be used to better understand RF devices and to develop superior, efficient, and safer products more quickly.

Efficacy and safety of B-ultrasound-guided radiofrequency ablation in the treatment of primary liver cancer: Systematic review and metaanalysis

BACKGROUND Primary liver cancer is one of the most lethal malignancies in the world.Tradi-tional treatment methods have limitations in terms of efficacy and safety.Ra-diofrequency ablation(RFA)guided by B-ultrasound,as a minimally invasive treatment,has attracted increasing attention in the treatment of primary liver cancer in recent years.AIM To study the efficacy and safety of RFA were compared with those of traditional surgery(TS)for treating small liver cancer.METHODS At least 2 people were required to search domestic and foreign public databases,including foreign databases such as EMBASE,PubMed and the Cochrane Library,and Chinese databases such as the China National Knowledge Infrastructure database,China Biomedical Literature database,Wanfang database and VIP database.Controlled trials of RFA vs conventional surgery for small liver cancer were retrieved from January 2008 to January 2023.They were screened and eva-luated according to the quality evaluation criteria in the Cochrane Handbook of Systematic Reviews.The meta-analysis was performed using RevMan 5.3 soft-ware.RESULTS A total of 10 studies were included in this study,including 1503 patients in the RFA group and 1657 patients in the surgery group.The results of the meta-ana-lysis showed that there was no significant difference in 1-year overall survival between the two groups(P>0.05),while the 3-year and 5-year overall survival rates and 1-year,3-year and 5-year tumor-free survival rates in the surgery group were greater than those in the RFA group(P<0.05).In terms of complications,the incidence of complications in the RFA group was lower than that in the surgery group(P<0.05).CONCLUSION In terms of long-term survival,TS is better than RFA for small liver cancer patients.However,RFA has fewer complications and is safer.

Radiofrequency sensing systems based on emerging two-dimensional materials and devices

As one of the most promising platforms for wireless communication,radiofrequency(RF)electronics have been widely advocated for the development of sensing systems.In particular,monolayer and few-layer two-dimensional(2D)materials exhibiting extraordinary electrical properties not only can be integrated to improve the performance of RF circuits,but also to display exceptional sensing capabilities.This review provides an in-depth perspective of current trends and challenges in the application of 2D materials for RF biochemical sensing,including:(i)theoretical bases to achieve different sensing schemes;(ii)unique properties of 2D materials for reasoning their applications in RF sensing;(iii)developments in 2D RF sensors to facilitate the practice of biochemical sensors with ever-demanding sensitivities,as well as their potential uses in meeting the requirements and challenges of biochemical sensors in the Internet-of-Things era.

Efficacy of radiofrequency ablation combined with sorafenib for treating liver cancer complicated with portal hypertension and prognostic factors

BACKGROUND Patients with liver cancer complicated by portal hypertension present complex challenges in treatment.AIM To evaluate the efficacy of radiofrequency ablation in combination with sorafenib for improving liver function and its impact on the prognosis of patients with this condition.METHODS Data from 100 patients with liver cancer complicated with portal hypertension from May 2014 to March 2019 were analyzed and divided into a study group(n=50)and a control group(n=50)according to the treatment regimen.The research group received radiofrequency ablation(RFA)in combination with sorafenib,and the control group only received RFA.The short-term efficacy of both the research and control groups was observed.Liver function and portal hypertension were compared before and after treatment.Alpha-fetoprotein(AFP),glypican-3(GPC-3),and AFP-L3 levels were compared between the two groups prior to and after treatment.The occurrence of adverse reactions in both groups was observed.The 3-year survival rate was compared between the two groups.Basic data were compared between the survival and non-surviving groups.To identify the independent risk factors for poor prognosis in patients with liver cancer complicated by portal hypertension,multivariate logistic regression analysis was employed.RESULTS When comparing the two groups,the research group's total effective rate(82.00%)was significantly greater than that of the control group(56.00%;P<0.05).Following treatment,alanine aminotransferase and aspartate aminotransferase levels increased,and portal vein pressure decreased in both groups.The degree of improvement for every index was substantially greater in the research group than in the control group(P<0.05).Following treatment,the AFP,GPC-3,and AFP-L3 levels in both groups decreased,with the research group having significantly lower levels than the control group(P<0.05).The incidence of diarrhea,rash,nausea and vomiting,and fatigue in the research group was significantly greater than that in the control group(P<0.05).The 1-,2-,and 3-year survival rates of the research group(94.00%,84.00%,and 72.00%,respectively)were significantly greater than those of the control group(80.00%,64.00%,and 40.00%,respectively;P<0.05).Significant differences were observed between the survival group and the non-surviving group in terms of Child-Pugh grade,history of hepatitis,number of tumors,tumor size,use of sorafenib,stage of liver cancer,histological differentiation,history of splenectomy and other basic data(P<0.05).Logistic regression analysis demonstrated that high Child-Pugh grade,tumor size(6–10 cm),history of hepatitis,no use of sorafenib,liver cancer stage IIIC,and previous splenectomy were independent risk factors for poor prognosis in patients with liver cancer complicated with portal hypertension(P<0.05).CONCLUSION Patients suffering from liver cancer complicated by portal hypertension benefit from the combination of RFA and sorafenib therapy because it effectively restores liver function and increases survival rates.The prognosis of patients suffering from liver cancer complicated by portal hypertension is strongly associated with factors such as high Child-Pugh grade,tumor size(6-10 cm),history of hepatitis,lack of sorafenib use,liver cancer at stage IIIC,and prior splenectomy.

Efficacy and safety of percutaneous transhepatic biliary radiofrequency ablation in patients with malignant obstructive jaundice

BACKGROUND Percutaneous transhepatic cholangiodrainage(PTCD)and endoscopic retrograde cholangiopancreatography/endoscopic nasobiliary drainage are the most common clinical procedures for jaundice control in patients with unresectable malignant obstructive jaundice,yet the safety and effect of endobiliary radiofrequency ablation(EB-RFA)combined PTCD is rarely reported,in this article,we report our experience of EB-RFA combined PTCD in such patients.AIM To retrospectively study the efficacy and safety of EB-RFA combined PTCD in patients with unresectable malignant obstructive jaundice.METHODS Patients with unresectable malignant obstructive jaundice treated with EB-RFA under PTCD were selected,the bile ducts of the right posterior lobe was selected as the target bile ducts in all cases.The general conditions of all patients,preoperative tumour markers,total bilirubin(TBIL),direct bilirubin(DBIL),albumin(ALB),alkaline phosphatase(ALP),and glutamyl transferase(GGT)before and on the 7th day after the procedure,as well as perioperative complications,stent patency time and patient survival were recorded.RESULTS All patients successfully completed the operation,TBIL and DBIL decreased significantly in all patients at the 7th postoperative day(P=0.009 and 0.006,respectively);the values of ALB,ALP and GGT also decreased compared with the preoperative period,but the difference was not statistically significant.Perioperative biliary bleeding occurred in 2 patients,which was improved after transfusion of blood and other conservative treatments,pancreatitis appeared in 1 patient after the operation,no serious complication and death happened after operation.Except for 3 patients with loss of visits,the stent patency rate of the remaining 14 patients was 100%71%and 29%at the 1^(st),3^(rd),and 6^(th)postoperative months respectively,with a median survival of 4 months.CONCLUSION EB-RFA under PTCD in patients with unresectable malignant obstructive jaundice has a satisfactory therapeutic effect and high safety,which is worthy of further clinical practice.

Severe hypoxemia after radiofrequency ablation for atrial fibrillation in palliatively repaired tetralogy of Fallot: A case report

BACKGROUND Patients with tetralogy of Fallot(TOF)often have arrhythmias,commonly being atrial fibrillation(AF).Radiofrequency ablation is an effective treatment for AF and does not usually cause severe postoperative hypoxemia,but the risk of complications may increase in patients with conditions such as TOF.CASE SUMMARY We report a young male patient with a history of TOF repair who developed severe hypoxemia after radiofrequency ablation for AF and was ultimately confirmed to have a new right-to-left shunt.The patient subsequently underwent atrial septal occlusion and eventually recovered.CONCLUSION Radiofrequency ablation may cause iatrogenic atrial septal injury;thus possible complications should be predicted in order to ensure successful treatment and patient safety.

Percutaneous transhepatic cholangiography:An effective option for endo-biliary radiofrequency ablation before stent insertion in unresectable biliary cancer?

Biliary cancer is a highly aggressive disease that is typically diagnosed at advanced stages when surgical removal is no longer an option.In these cases,palliative care and mechanical widening of the blocked biliary system are preferred.The insertion of a stent is often necessary to prevent the recurrence of blockages caused by cancer progression.Prior to stent placement,endo-biliary radiofrequency ablation(EB-RFA)appears to result in longer-lasting stent effectiveness without increasing the risk of severe complications.However,its impact on overall survival is not yet clear.Additionally,while endoscopic retrograde cholangiopancreatography is the most common method for performing EB-RFA,percutaneous transhepatic cholangiodrainage seems to be a safe and potentially more efficient alternative,particularly for long,angulated,or significantly narrowed bile ducts.

Nomogram predicting the prognosis of primary liver cancer after radiofrequency ablation combined with transcatheter arterial chemoembolization

BACKGROUND The incidence and mortality rates of primary hepatocellular carcinoma(HCC)are high,and the conventional treatment is radiofrequency ablation(RFA)with transcatheter arterial chemoembolization(TACE);however,the 3-year survival rate is still low.Further,there are no visual methods to effectively predict their prognosis.AIM To explore the factors influencing the prognosis of HCC after RFA and TACE and develop a nomogram prediction model.METHODS Clinical and follow-up information of 150 patients with HCC treated using RFA and TACE in the Hangzhou Linping Hospital of Traditional Chinese Medicine from May 2020 to December 2022 was retrospectively collected and recorded.We examined their prognostic factors using multivariate logistic regression and created a nomogram prognosis prediction model using the R software(version 4.1.2).Internal verification was performed using the bootstrapping technique.The prognostic efficacy of the nomogram prediction model was evaluated using the concordance index(CI),calibration curve,and receiver operating characteristic RESULTS Of the 150 patients treated with RFA and TACE,92(61.33%)developed recurrence and metastasis.Logistic regression analysis identified six variables,and a predictive model was created.The internal validation results of the model showed a CI of 0.882.The correction curve trend of the prognosis prediction model was always near the diagonal,and the mean absolute error before and after internal validation was 0.021.The area under the curve of the prediction model after internal verification was 0.882[95%confidence interval(95%CI):0.820-0.945],with a specificity of 0.828 and sensitivity of 0.656.According to the Hosmer-Lemeshow test,χ2=3.552 and P=0.895.The predictive model demonstrated a satisfactory calibration,and the decision curve analysis demonstrated its clinical applicability.CONCLUSION The prognosis of patients with HCC after RFA and TACE is affected by several factors.The developed prediction model based on the influencing parameters shows a good prognosis predictive efficacy.

Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence worldwide.As a common local treatment,RFA has attracted much attention for its efficacy and influence on liver function.AIM To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by RFA.METHODS The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and June 2023 were collected.The chi-square test was used to compare the data between groups.The Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before treatment.RESULTS The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,respectively.The difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,respectively.The difference between the two groups was statist-ically significant(P<0.001).Serum ALP[hazard ratio(HR)=1.766,95%confidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic factor.The 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,respectively.The difference between the two groups was statistically significant(P<0001).The 1-year PFS rates were 81%and 56%in patients with normal and abnormal serum GGT levels before treatment,respectively;the 2-year PFS rates were 62%and 35%,respectively;and the 5-year PFS rates were 18%and 7%,respectively,with statistical significance between the two groups(P<0.001).The serum ALP concentration(HR=1.653,95%CI:1.001-2.729,P=0.049)and GGT(HR=1.949,95%CI:1.296-2.930,P=0.001)was closely associated with PFS after RFA in patients with PLC.The proportion of male patients with abnormal ALP levels is high,the Child-Pugh grade of liver function is poor,and the incidence of ascites is high.Among GGT-abnormal patients,the Child-Pugh grade of liver function was poor,the tumor stage was late,the proportion of patients with tumors≥5 cm was high,and the incidence of hepatic encephalopathy was high.CONCLUSION Serum ALP and GGT levels before treatment can be used to predict the prognosis of patients with PLC after RFA,and they have certain guiding significance for the long-term survival of patients with PLC after radiofrequency therapy.

Radiofrequency ablation combined with transcatheter arterial chemoembolization for recurrent liver cancer

BACKGROUND The recurrence rate of liver cancer after surgery is high.Radiofrequency ablation(RFA)combined with transcatheter arterial chemoembolization(TACE)is an effective treatment for liver cancer;however,its efficacy in recurrent liver cancer remains unclear.AIM To investigate the clinical effect of TACE combined with RFA in the treatment of recurrent liver cancer.METHODS Ninety patients with recurrent liver cancer were divided into 2 groups according to treatment plan:Control(RFA alone);and experimental[TACE combined with RFA(TACE+RFA)].The incidence of increased alanine aminotransferase levels,complications,and other indices were compared between the two groups before and after the procedures.RESULTS One month after the procedures,the short-term efficacy rate and Karnofsky Performance Status scores of the experimental group were significantly higher than those of the control group(P<0.05).Alpha-fetoprotein(AFP)and total bilirubin levels were lower than those in the control group(P<0.05);The overall response rate was 82.22%and 66.67%in the experimental and control groups,respectively;The disease control rate was 93.33%and 82.22%in the experimental and control groups,respectively,the differences are statistically significant(P<0.05).And there were no statistical differences in complications between the two groups(P>0.05).CONCLUSION TACE+RFA was effective for the treatment of recurrent liver cancer and significantly reduced AFP levels and improved various indices of liver function.

New Rotative Radiofrequency Technology: A Multicenter Retrospective Study on Efficacy and Safety

Background: Non-ablative radiofrequency (RF) technology is widely used for the treatment of signs of aging, skin laxity, localized fat and cellulite. However, many RF devices suffer from technical limitations that make the results highly dependent on the user’s experience or clinical limitations that compromise safety, efficacy and comfort. Objective: To evaluate the efficacy and safety of a novel semi-automatic non-ablative RF device for skin tightening, body shaping and cellulite reduction. Materials and methods: A retrospective multicenter study was performed using a novel rotative RF device with temperature and impedance control (Sculpt&Shape®, Sinclair, Spain). 58 subjects underwent a minimum of 4 treatments every 1-2 weeks. A total of 120 treatments (56.7% body and 43.3% facial) and 1034 sessions were performed. Efficacy was evaluated by 3 researchers using the Global Aesthetic Improvement Scale (GAIS) and anthropometric measurements were collected. Subject and practitioner satisfaction were recorded. Safety was evaluated by analyzing the perception of pain during the treatment and the side and adverse effects immediately after treatment and over the next 48 hours. Results: Between 25% and 50% improvement was achieved according to the GAIS. Statistically significant (p < 0.01) abdominal fold reduction of 5.1 mm and circumference reduction of 32.0 mm, 16.4 mm and 13.9 mm were recorded for the abdomen, legs and arms, respectively. 77.5% of subjects and 94.9% of practitioners were either satisfied or very satisfied. Minor adverse effects were found in 0.97% of the sessions. Conclusion: This novel semi-automatic rotative RF device has been found to provide treatments that are effective, safe and comfortable for both practitioners and subjects. .

Recurrence and survival following microwave, radiofrequency ablation, and hepatic resection of colorectal liver metastases: A systematic review and network meta-analysis

Background: Gold standard for colorectal liver metastases(CRLM) remains hepatic resection(HR). However, patients with severe comorbidities, unresectable or deep-situated resectable CRLM are candidates for ablation. The aim of the study was to compare recurrence rate and survival benefit of the microwave ablation(MWA), radiofrequency ablation(RFA) and HR by conducting the first network meta-analysis. Data sources: Systematic search of the literature was conducted in the electronic databases. Both updated traditional and network meta-analyses were conducted and the results were compared between them. Results: HR cohort demonstrated significantly less local recurrence rate and better 3-and 5-year diseasefree(DFS) and overall survival(OS) compared to MWA and RFA cohorts. HR cohort included significantly younger patients and with significantly lower preoperative carcinoembryonic antigen(CEA) by 10.28 ng/m L compared to RFA cohort. Subgroup analysis of local recurrence and OS of solitary and ≤3 cm CRLMs did not demonstrate any discrepancies when compared with the whole sample. Conclusions: For resectable CRLM the treatment of choice still remains HR. MWA and RFA can be used as a single or adjunct treatment in patients with unresectable CRLM and/or prohibitive comorbidities.

Treatment of high-grade dysplasia and intramucosal carcinoma using radiofrequency ablation or endoscopic mucosal resection + radiofrequency ablation: Meta-analysis and systematic review

BACKGROUND The progression of Barrett's esophagus(BE) to early esophageal carcinoma occurs sequentially; the metaplastic epithelium develops from a low-grade dysplasia to a high-grade dysplasia(HGD), resulting in early esophageal carcinoma and,eventually, invasive carcinoma. Endoscopic approaches including resection and ablation can be used in the treatment of this condition.AIM To compare the effectiveness of radiofrequency ablation(RFA) vs endoscopic mucosal resection(EMR) + RFA in the endoscopic treatment of HGD and intramucosal carcinoma.METHODS In accordance with PRISMA guidelines, this systematic review included studies comparing the two endoscopic techniques(EMR + RFA and RFA alone) in the treatment of HGD and intramucosal carcinoma in patients with BE. Our analysis included studies involving adult patients of any age with BE with HGD or intramucosal carcinoma. The studies compared RFA and EMR + RFA methods were included regardless of randomization status.RESULTS The seven studies included in this review represent a total of 1950 patients, with742 in the EMR + RFA group and 1208 in the RFA alone group. The use of EMR +RFA was significantly more effective in the treatment of HGD [RD 0.35(0.15,0.56)] than was the use of RFA alone. The evaluated complications(stenosis,bleeding, and thoracic pain) were not significantly different between the two groups.CONCLUSION Endoscopic resection in combination with RFA is a safe and effective method in the treatment of HGD and intramucosal carcinoma, with higher rates of remission and no significant differences in complication rates when compared to the use of RFA alone.

Endoscopic ultrasound guided radiofrequency ablation for pancreatic tumors: A critical review focusing on safety, efficacy and controversies

The role of endoscopic ultrasound(EUS)in the last two decades has shifted from a diagnostic tool to an important therapeutic tool treating mainly pancreatobiliary disorders.In recent years,its applications for treating pancreatic diseases have broadened,including the implementation of radiofrequency ablation(RFA),which has been traditionally used for treating solid tumors.In this critical indepth review,we summarized all the papers throughout the literature regarding EUS-RFA for pancreatic neuroendocrine neoplasms,adenocarcinoma,and pancreatic cystic lesions.Overall,for pancreatic neuroendocrine neoplasms we identified 16 papers that reported 96 patients who underwent EUS-RFA,with acceptable adverse events that were rated mild to moderate and a high complete radiological resolution rate of 90%.For pancreatic adenocarcinoma,we identified 8 papers with 121 patients.Adverse events occurred in 13%of patients,mostly rated mild.However,no clear survival benefit was demonstrated.For pancreatic cystic lesions,we identified 4 papers with 38 patients.The adverse events were mostly mild and occurred in 9.1%of patients,and complete or partial radiological resolution of the cysts was reported in 36.8%.Notably,the procedure was technically feasible for most of the patients.Nevertheless,a long road remains before this technique finds its definite place in guidelines due to several controversies.EUS-RFA for pancreatic tumors seems to be safe and effective,especially for pancreatic neuroendocrine neoplasms,but multicenter prospective trials are needed to consider this treatment as a gold standard.

Radiofrequency ablation with or without transarterial chemoembolization for hepatocellular carcinoma: A systematic review and meta-analysis

AIM: To determine whether combined transarterial chemoembolization(TACE) and radiofrequency ablation(RFA) improve overall and recurrence-free survival(RFS) compared with RFA alone. METHODS: We reviewed randomized clinical trials(RCTs) comparing overall survival rate as well as recurrence-free rate for hepatocellular carcinoma(HCC) between TACERFA therapy and RFA alone published before April 2015 by conducting a systematic review and meta-analysis. Eligible studies were identified by searching Pub Med and EMBASE up to April 2015. Additional studies were retrieved via China Medical Collections, Google Scholar or a hand review of the reference lists of the retrieved articles. The summarized relative risks(RRs) with their 95%CIs were estimated using random-effects model. I2 statistic was calculated to measure the heterogeneity of RRs across studies and Cochran's Q test was used to test the statistical significance accordingly. Publication bias was assessed primarily based on visual assessment using a funnel plot, and secondly by using Egger's regression asymmetry test or Begg's rank correlation test as appropriate. Meta-regression was implemented to examine potential effect modifiers. RESULTS: Nine single-center RCTs conducted in China and Japan were included, with a total of 618 patients with HCC; 321 of whom(51.9%) received TACE/RFA therapy and 297 received RFA alone. The pooled RRs with corresponding CIs comparing combined TACE/RFA to RFA alone were 1.12(1.004-1.26) and 1.20(1.02-1.41) for 1-year and 3-year survival rates, respectively. Similar positive associations were found for 1-year(1.19; 1.05-1.35) and 3-year(1.44; 1.00-2.07) RFS. Thebeneficial effect was more evident in patients with medium-sized(3-5 cm) tumors and among the Chinese population. CONCLUSION: Combined TACE/RFA has a beneficial effect on survival and recurrence rates compared with RFA alone, especially for medium-sized HCC and among Chinese patients.

Outcomes of microwave versus radiofrequency ablation for hepatocellular carcinoma:A systematic review and meta-analysis

BACKGROUND Studies to date comparing outcomes of microwave ablation(MWA)with radiofrequency ablation(RFA)on patients with hepatocellular carcinoma have yielded conflicting results,with no clear superiority of one technique over the other.The aim of this systematic review and meta-analysis was to compare the efficacy and safety of MWA with RFA.AIM To perform a systematic review and meta-analysis comparing the efficacy and safety of MWA with RFA.METHODS A systematic literature search was performed using Ovid Medline,Embase,PubMed,Reference Citation Analysis,Cochrane Central and Cochrane Systematic Review databases,and Web of Science.Abstracts and full manuscripts were screened for inclusion utilising predefined inclusion and exclusion criteria comparing outcomes of MWA and RFA.A random-effects model was used for each outcome.Meta-regression analysis was performed to adjust for the difference in follow-up period between the studies.Primary outcome measures included complete ablation(CA)rate,local recurrence rate(LRR),survival[local recurrence-free survival(LRFS),overall survival(OS)]and adverse events.RESULTS A total of 42 published studies[34 cohort and 8 randomised controlled trials(RCT)]with 6719 patients fulfilled the selection criteria.There was no significant difference in tumour size between the treatment groups.CA rates between MWA and RFA groups were similar in prospective cohort studies[odds ratio(OR)0.95,95%confidence interval(CI)0.28–3.23]and RCTs(OR 1.18,95%CI 0.64–2.18).However,retrospective studies reported higher rates with MWA(OR 1.29,95%CI 1.06–1.57).Retrospective cohort studies reported higher OS(OR 1.54,95%CI 1.15–2.05 and lower LRR(OR 0.67,95%CI 0.51–0.87).No difference in terms of LRFS or 30-d mortality was observed between both arms.MWA had an increased rate of adverse respiratory events when compared to RFA(OR 1.99,95%CI 1.07–3.71,P=0.03).CONCLUSION MWA achieves similar CA rates and as good or better longer-term outcomes in relation to LRR and OS compared to RFA.Apart from an increased rate of respiratory events post procedure,MWA is as safe as RFA.

Long-term radiofrequency electromagnetic fields exposure attenuates cognitive dysfunction in 5×FAD mice by regulating microglial function

We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,including microglia.To examine whether this therapeutic effect is due to the regulation of activated microglia,we analyzed mic roglial gene expression profiles and the existence of microglia in the brain in this study.5xFAD mice at the age of 1.5 months were assigned to sham-and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months.We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/a myloid-beta metabolism in brain tissue.We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-βdeposition.The expression levels of Iba1(pan-microglial marker)and colony-stimulating factor 1 receptor(CSF1R;regulates microglial prolife ration)in the hippocampus in 5xFAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group.Subsequently,we analyzed the expression levels of genes related to mic rogliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor(PLX3397)-treated group.Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis(Csf1r,CD68,and Ccl6)and pro-inflammatory cytokine interleukin-1β.N otably,the expression levels of genes related to mic roglial function,including Trem2,Fcgr1α,Ctss,and Spi1,were decreased after long-term radiofrequency electromagnetic field exposure,which was also observed in response to microglial suppression by PLX3397.These results showed that radiofrequency electromagnetic fields ameliorated amyloid-βpathology and cognitive impairment by suppressing amyloid-βdeposition-induced microgliosis and their key regulator,CSF1R.

Radiofrequency ablation is an inferior option to liver resection for solitary hepatocellular carcinoma≤5 cm without cirrhosis:A population-based study with stratification by tumor size

Background:About 10%-20%of all individuals who develop hepatocellular carcinoma(HCC)do not have cirrhosis.Comparisons are rarely reported regarding the effectiveness of radiofrequency ablation(RFA)and liver resection(LR)in survival of HCC without cirrhosis and stratification by tumor size≤5 cm.Methods:We used the Surveillance,Epidemiology,and End Results(SEER)database and identified 1505 patients with a solitary HCC tumor≤5 cm who underwent RFA or LR during 2004-2015.Patients were classified into non-cirrhosis and cirrhosis groups and each group was categorized into three subgroups,according to tumor size(≤30 mm,31-40 mm,41-50 mm).Results:In patients without cirrhosis,LR showed better 5-year HCC cancer-specific survival than RFA in all tumor size subgroups(≤30 mm:82.51%vs.56.42%;31-40 mm:71.31%vs.46.83%;41-50 mm:74.7%vs.37.5%;all P<0.05).Compared with RFA,LR was an independent protective factor for HCC cancer-specific survival in multivariate Cox analysis[≤30 mm:hazard ratio(HR)=0.533,95%confidence interval(CI):0.313-0.908;31-40 mm:HR=0.439,95%CI:0.201-0.957;41-50 mm:HR=0.382;95%CI:0.159-0.916;all P<0.05].In patients with cirrhosis,for both tumor size≤30 mm and 31-40 mm groups,there were no significant survival differences between RFA and LR in multivariate analysis(all P>0.05).However,in those with tumor size 41-50 mm,LR showed significantly better 5-year HCC cancer-specific survival than RFA in both univariate(54.72%vs.23.06%;P<0.001)and multivariate analyses(HR=0.297;95%CI:0.136-0.648;P=0.002).Conclusions:RFA is an inferior treatment option to LR for patients without cirrhosis who have a solitary HCC tumor≤5 cm.

Radiofrequency ablation for renal tumours: A retrospective study from a tertiary centre

Objective:This study aimed to evaluate the safety and efficacy outcomes of percutaneous radiofrequency ablation(RFA)for localised renal cell carcinoma(RCC)in a tertiary hospital patient who remained unfit for surgical intervention.Methods:We retrospectively analysed survival outcomes for patients with biopsy proven RCC treated by RFA at Royal Perth Hospital between September 2009 and May 2018.Complication data were gathered for all patients that underwent renal RFA along with 2-and 5-year recurrence-free survival(RFS)rate and compared the outcomes with data from previous studies.Results:A total of 69 patients(73 procedures)were eligible for the study,and those patients had biopsy-proven RCC with a minimum of 2-year follow-up.The complication rate was 8.2%(6/73)and local recurrence rate 9.6%(7/73).Two-year RFS is 95.7% and 5-year RFS is 78.8% on a median 3.82-year follow-up(interquartile range 1.90-5.75 years).Conclusion:RFA performed at our centre was found to be safe and effective with low complication rates and durable RFS in line with expectations from existing research.Our study demonstrated that RFA is an alternative modality of treatment for small renal tumours in patients unfit for surgical approach.

Endoscopic biliary treatment of unresectable cholangiocarcinoma: A meta-analysis of survival outcomes and systematic review

BACKGROUND Endoscopic radiofrequency ablation(ERFA),percutaneous radiofrequency ablation(PRFA),and photodynamic therapy(PDT),when used in conjunction with conventional biliary stenting,have demonstrated a survival benefit in patients with unresectable cholangiocarcinoma.AIM To compare pooled survival outcomes,adverse event rates,and mean stent patency for those undergoing these procedures.METHODS A comprehensive literature review of published studies and abstracts from January 2011 to December 2020 was performed comparing survival outcomes in patients undergoing ERFA with stenting,biliary stenting alone,PRFA with stenting,and PDT with stenting for unresectable cholangiocarcinoma(CCA).RESULTS Data from four studies demonstrated a pooled mean survival favoring ERFA as compared to biliary stenting alone(12.0±0.9 mo vs 6.8±0.3 mo,P<0.001)as well as statistically improved median survival time(13 mo vs 8 mo,P<0.001).Both ERFA with stenting and PRFA with stenting groups demonstrated statistical superiority to biliary stenting alone(P<0.001 and P=0.004,respectively).However,when comparing ERFA to PRFA,pooled data demonstrated overall higher mean survival in the ERFA with stenting cohort as compared to PRFA with stent cohort(12.0+0.9 mo vs 8.1+2.1 mo,P<0.0001).Data from two studies demonstrated a pooled median survival favoring ERFA with stenting as compared to PDT with stenting(11.3 mo vs 8.5 mo,P=0.02).CONCLUSION While further prospective,randomized studies are needed to assess efficacy of ERFA,our metaanalysis demonstrated that this technique offers endoscopists a reasonable palliative method by which to treat patients with unresectable CCA that results in longer survival as compared to biliary stenting alone,percutaneous radiofrequency ablation with biliary stenting,and PDT with biliary stenting as well as an acceptable adverse event profile based on available published data.