The modern use of radiofrequency energy in surgery, endoscopy and interventional radiology

Percutaneous endobiliary radiofrequency ablation and stent placement for unresectable malignant biliary obstruction: a propensity score matching retrospective study

BACKGROUND

Whether endobiliary radiofrequency ablation (EB-RFA) changes the standard role of stent placement in treating unresectable malignant biliary obstruction (MBO) remains unclear. The aim of this study is to compare percutaneous EB-RFA and metal stent placement (RFA-Stent) with metal stent placement alone (Stent) in treating unresectable MBO using a propensity score matching (PSM) analysis.

METHODS

From June 2013 to June 2018, clinical data from 163 patients with malignant biliary obstruction who underwent percutaneous RFA-Stent or stenting alone were retrospectively analyzed using a nearest-neighbor algorithm to one-to-one PSM analysis to compare primary and secondary stent patency (PSP, SSP), overall survival (OS) and complications between the two groups.

RESULTS

Before matching, for whole patients, RFA-Stent resulted in longer median PSP (8.0 vs. 5.1 months, P = 0.003), SSP (9.8 vs. 5.1 months, P < 0.001) and OS (7.0 vs. 4.5 months, P = 0.034) than the Stent group. After matching (54 pairs), RFA-Stent also resulted in better median PSP (8.5 vs. 5.1 months, P < 0.001), SSP (11.0 vs. 6.0 months, P < 0.001), and OS (8.0 vs. 4.0 months, P = 0.007) than Stent. RFA-Stent was comparable with Stent for complication rates. In Cox analysis, RFA-Stent modality and serum total bilirubin level were independent prognostic factors for PSP. RFA-Stent modality, performance status score and combination therapy after stent were independent prognostic factors for OS.

CONCLUSION

Percutaneous RFA-Stent was superior to Stent in terms of PSP, SSP, and OS in selected patients with unresectable MBO.

Recent Updates on Local Ablative Therapy Combined with Chemotherapy for Extrahepatic Cholangiocarcinoma: Photodynamic Therapy and Radiofrequency Ablation

Although chemotherapy constitutes of the first-line standard therapy for unresectable extrahepatic cholangiocarcinoma, the treatment outcomes are unsatisfactory. In recent years, local ablative therapy, which is delivered to the cholangiocarcinoma lesion via the percutaneous or endoscopic approach, has garnered attention for the treatment of unresectable, extrahepatic cholangiocarcinoma. Local ablative therapy, such as photodynamic therapy and radiofrequency ablation, can achieve local tumor control. A synergistic effect may also be expected when local ablative therapy is combined with chemotherapy. However, it is a long way from being entrenched as an established therapeutic technique, and several unresolved problems persist, including the paucity of evidence comparing photodynamic therapy and radiofrequency ablation. Clinical application of photodynamic therapy and radiofrequency ablation requires sound comprehension and assimilation of the available evidence to truly benefit each individual patient. In this study, we reviewed the current status, issues, and future prospects of photodynamic therapy and radiofrequency ablation for extrahepatic cholangiocarcinoma, with a special focus on their combination with chemotherapy.

Updated evidence on the clinical impact of endoscopic radiofrequency ablation in the treatment of malignant biliary obstruction

Endoscopic biliary radiofrequency ablation (RFA) was recently developed as a novel adjunctive procedure and a promising therapeutic option in patients with malignant biliary obstruction (MBO). RFA can achieve local tumor control, resulting in improved biliary stent patency and a potential survival benefit. However, the efficacy of biliary RFA remains controversial, and previous studies have shown conflicting results. At present, extrahepatic cholangiocarcinoma is considered the condition most effectively treated by biliary RFA, but there is limited research even on this point. Further, limitations of RFA associated with the devices used during the procedure are an important subject of discussion. In addition to further well-designed clinical trials, development of innovative devices is warranted to investigate and conclusively establish the usefulness of biliary RFA. In this review we summarize the updated evidence regarding the use of endoscopic biliary RFA for MBO and discuss issues that should be addressed in future studies.

Endoscopic ultrasound-guided radiofrequency ablation: An effective and safe alternative for the treatment of benign insulinoma

BACKGROUND

Insulinomas are usually benign, small-sized, well-encapsulated and often solitary pancreatic tumors. Currently, enucleation is the treatment of choice for sporadic solitary insulinoma if diameter is less than 2cm and the structural integrity of the pancreatic duct can be maintained. However, the procedure has a risk of postoperative complications, and especially of pancreatic fistula. There is growing interest in endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) as an effective and less invasive alternative treatment for benign sporadic insulinoma.

METHOD

We retrospectively analyzed the efficacy and safety of EUS-RFA in four patients with benign localized insulinoma treated in our tertiary care center between June 2018 and November 2019. EUS-RFA was performed with a EUS-guided RFA 19-gauge needle electrode (Starmed; Taewoong Medical, Seoul, South Korea) that released energy at 50W up to 100 Ohms impedance.

RESULTS

The series comprised three women and one man, with a median age of 58 years (range 52-82 years). Mean tumor size was 12mm. Although three of the four patients would have been eligible for surgery, EUS-RFA was proposed to them. Symptomatic and biological improvement occurred immediately, generally straight after the procedure, in all patients, and no serious complications were observed. During the mean follow-up period of 22 months, no symptom recurrence was observed.

CONCLUSIONS

This preliminary report in 4 patients showed that EUS-RFA was an effective and relatively safe alternative treatment, devoid of major complications, for benign sporadic insulinoma. Larger-scale prospective multicenter studies are, however, needed to confirm the long-term effectiveness and safety of this novel technique.

Endoscopic radiofrequency biliary ablation treatment: A comprehensive review

Radiofrequency ablation (RFA) functions by delivering thermal energy within tissue, the result of a high-frequency alternating current released from an active electrode, leading to coagulative necrosis and cellular death. Recently, a biliary catheter working on a guidewire has been developed and a number of studies have so far been carried out. The present article provides a comprehensive review of the literature on the results of the use of RFA for the clinical management of patients with unresectable malignant biliary strictures, benign biliary strictures, and residual adenomatous tissue in the bile duct after endoscopic papillectomy. Available data show that biliary RFA treatment is a promising adjuvant therapy in patients with unresectable malignant biliary obstruction. The procedure is safe, well tolerated and improves stent patency and survival, even though more studies are warranted. In patients with residual endobiliary adenomatous tissue after endoscopic papillectomy, a significant rate of neoplasia eradication after a single RFA session has been reported, thus favoring this treatment over surgical intervention. In these patients, as well as in those with benign biliary strictures, dedicated probes with a short electrode able to focus the RF current on the short stenosis are needed to expand RFA treatment for these indications.

Percutaneous endobiliary radiofrequency ablation for refractory benign hepaticojejunostomy and biliary strictures

PURPOSE

The objective of this study was to determine the safety and efficacy of percutaneous endobiliary radiofrequency ablation (ERFA) and balloon dilation for the treatment of hepaticojejunostomy (HJ) strictures resistant to surgery and/or other interventions.

MATERIALS AND METHODS

Eighteen patients who underwent percutaneous ERFA for HJ stricture were included. There were 10 men and 8 women with a mean age of 48.3±10.8 (SD) years (range: 33-69 years). The 18 patients had a total of 29 benign HJ strictures secondary to cholecystectomy (14 patients; 78.0%), Whipple procedure (3 patients; 16.6%) or blunt abdominal trauma (1 patient; 5.4%). The different end-points were technical success, clinical success, recurrence, procedure-related mortality, and morbidity.

RESULTS

Technical and clinical success rates were 100% and 83.3%, respectively. No mortality and major procedure-related complications were observed. One patient experienced minor complication (self-limited pleural effusion). Two patients did not show favorable response to ERFA whereas 10 patients had no stricture recurrence during a mean follow-up period of 7.3 months±1.0 (SD) (range: 4-10 months).

CONCLUSION

ERFA is a safe and effective treatment for benign HJ and biliary strictures. However, more studies involving more patients with a long-term follow-up period should be made to fully determine the long-term results of ERFA.

The safety and efficacy of percutaneous intraductal radiofrequency ablation in unresectable malignant biliary obstruction: A single-institution experience

Background

Patients with unresectable malignant biliary obstruction have limited life expectancy because of limited stent patency and tumor progression. The aim of our study was to retrospectively evaluate the safety and efficacy of combining intraductal RFA with biliary metal stent placement for patients with malignant biliary obstruction.

Methods

Patients who received percutaneous intraductal RFA and biliary stent placement for malignant biliary obstruction between 2013 and 2015 were identified. Outcomes were stent patency, technique and clinical success rate, overall survival (OS) and complication rates. Kaplan-Meier and Cox regression analyses were used to examine the association of various factors with stent patency and OS. Complications and laboratory abnormalities were recorded.

Results

Fifty patients were treated with percutaneous RFA and stent placement. The rates of technical success and clinical success were 98% and 92%, respectively. The median stent patency was 7.0 (95% confidence interval [CI]: 5.3, 8.7) months and OS was 5.0 (95% CI: 4.0, 6.0) months. On univariable analysis, previously cholangitis was an independent poor prognosis factor for recurrent biliary obstruction. OS was improved in patients who received more than one intervention compared to those who received only one intervention (log-rank P = 0.007), and in those treated without versus those treated with sequential chemotherapy (log-rank P = 0.017). On multivariable analysis, the occurrence of more than one intervention (P = 0.019) had independent prognostic significance for OS.

Conclusion

Percutaneous RFA and stent placement is a technically safe and feasible therapeutic option for the palliative treatment of malignant biliary obstruction. The long-term efficacy and safety of the procedure is promising, but further study is required via randomized and prospective trials.

Percutaneous intraductal radiofrequency ablation for treatment of biliary stent occlusion: A preliminary result

AIM

To assess the feasibility and effectiveness of a novel application of percutaneous intraductal radiofrequency (RF) for the treatment of biliary stent obstruction.

METHODS

We specifically report a retrospective study presenting the results of percutaneous intraductal RF in patients with biliary stent occlusion. A total of 43 cases involving biliary stent obstruction were treated by placing an EndoHPB catheter and percutaneous intraductal RF was performed to clean stents. The stent patency was evaluated by cholangiography and follow-up by contrast enhanced computed tomography or ultrasound after the removal of the drainage catheter.

RESULTS

Following the procedures, of the 43 patients, 40 survived and 3 died with a median survival of 80.5 (range: 30-243) d. One patient was lost to follow-up. One patient had the stent patent at the time of last follow-up. Two patients with stent blockage at 35 d and 44 d after procedure underwent percutaneous transhepatic drain insertion only. The levels of bilirubin before and after the procedure were 128 ± 65 μmol/L and 63 ± 29 μmol/L, respectively. There were no related complications (haemorrhage, bile duct perforation, bile leak or pancreatitis) and all patients’ stent patency was confirmed by cholangiography after the procedure, with a median patency time of 107 (range: 12-180) d.

CONCLUSION

This preliminary clinical study demonstrated that percutaneous intraductal RF is safe and effective for the treatment of biliary stent obstruction, increasing the duration of stent patency, although randomized controlled trials are needed to confirm the effectiveness of this approach.

The clinical utility of RFA in esophageal and cardia cancer patients with severe malignant obstruction

Malignant obstruction of esophageal and cardia cancer greatly affects the prognosis and life quality of patients. However, no better regimens have been reported up to now. In recent years, radiofrequency ablation (RFA) has been prospectively proven in the management of some tumors. So, we investigated the impact of RFA on the malignant obstruction of esophageal and cardia cancer. In this study, we evaluated the operation duration, ablation duration, immediate compilations, etc., and followed up for 12 months. Our findings showed that there existed no technical problems in all 22 patients with a mean operation duration of 58 min and mean ablation duration of 23 min. No complication was observed in addition to postoperative low pressure in one patient and retrostenal pain in another patient. Importantly, all 22 patients obtained complete remission with normal diet and felt no sense of obstruction. Mean hospitalization time was 3 days and then the 12-month follow-up continued. To our relief, re-obstruction was not observed in all patients for 2 months. In conclusion, the entire effect of RFA was satisfactory, and patients can obtain a better life quality, less pains, and complications. So RFA should be advocated and greatly investigated by more institutes and hospitals.

Percutaneous transhepatic cholangiography and intraductal radiofrequency ablation combined with biliary stent placement for malignant biliary obstruction

PURPOSE

To determine the safety and feasibility of percutaneous transhepatic cholangiography (PTC) and intraductal radiofrequency (RF) ablation combined with biliary stent placement for malignant biliary obstruction.

MATERIALS AND METHODS

Data from patients with unresectable malignant biliary obstruction who underwent PTC, intraductal RF ablation, and biliary stent placement (n = 12) or PTC and biliary stent placement only (control group; n = 14) were reviewed. Postoperative complications, jaundice remission, and stent patency were assessed.

RESULTS

All procedures were successful. No severe complications (eg, biliary bleeding, perforation) occurred. Two experimental group patients developed cholangitis, which resolved with conservative treatment. The 1-week jaundice remission and 3-month stent patency rates were similar in both groups, but the 6-month stent patency rate was higher in the experimental group (P < .05). In the experimental group, one death occurred as a result of gastrointestinal hemorrhage (unrelated to stent placement) by 3 months, and there were two cases of recurrent jaundice by 6 months. The latter two patients underwent repeat PTC, ablation, and stent placement. In the control group, one death occurred as a result of hepatic failure caused by progressive jaundice at 3 months, and another death resulted from disseminated intravascular coagulation caused by jaundice recurrence at 138 days after stent placement. In addition, seven patients developed jaundice recurrence (50-151 d after stent placement). PTC and repeat stent placement were performed in these patients.

CONCLUSIONS

Percutaneous transhepatic cholangiography and intraductal RF ablation combined with biliary stent placement for malignant biliary obstruction is safe and feasible and effectively prolongs stent patency time.

Intraductal radiofrequency ablation for management of malignant biliary obstruction

Self-expandable metal stents (SEMS) are the current standard of care for the palliative management of malignant biliary strictures. Recently, endoscopic ablative techniques with direct affect to local tumor have been developed to improve SEMS patency. Several reports have demonstrated the technical feasibility and safety of intraductal radiofrequency ablation (RFA), by both endoscopic and percutaneous approaches, in palliation of malignant strictures of the bile duct. Intraductal RFA has also been used in the treatment of occlusion of both covered and uncovered SEMS occlusion from tumor ingrowth or overgrowth. This article provides a comprehensive review of intraductal RFA in the management of malignant biliary obstruction.

Endoscopic radiofrequency ablation for cholangiocarcinoma

PURPOSE OF REVIEW

To describe the use of endobiliary radiofrequency ablation (RFA) in the treatment of malignant disease of the bile duct and offer a comprehensive review of the emerging evidence on the safety and effectiveness of this new technique.

RECENT FINDINGS

Ex-vivo and in-vivo porcine studies have been reported, confirming the feasibility of the technique, gathering preliminary safety data and defining appropriate power settings for human studies. Moderate-sized case series have now reported the use of RFA in mixed cohorts of human individuals with pancreatic cancer, cholangiocarcinoma and other malignant diseases of the bile duct. Endoscopic and percutaneous approaches have both been investigated. Small case series of blocked self-expanding metal stent clearance using RFA have been published.

SUMMARY

Intraductal RFA, via both endoscopic and percutaneous approaches, is feasible. Complication rates appear to be comparable with the current standard endoscopic and percutaneous approaches to palliation of malignant strictures of the bile duct. The current body of literature is germinal, but warrants the further investigation of planned clinical trials.

Safety and efficacy of radiofrequency ablation in the management of unresectable bile duct and pancreatic cancer: a novel palliation technique

Objectives. Radiofrequency ablation (RFA) has replaced photodynamic therapy for premalignant and malignant lesions of the esophagus. However, there is limited experience in the bile duct. The objective of this pilot study was to assess the safety and efficacy of RFA in malignant biliary strictures.

METHODS

Twenty patients with unresectable malignant biliary strictures underwent RFA with stenting between June 2010 and July 2012. Diameters of the stricture before and after RFA, immediate and 30 day complications and stent patency were recorded prospectively. Results. A total of 25 strictures were treated. Mean stricture length treated was 15.2 mm (SD = 8.7 mm, Range = 3.5-33 mm). Mean stricture diameter before RFA was 1.7 mm (SD = 0.9 mm, Range = 0.5-3.4 mm) while the mean diameter after RFA was 5.2 mm (SD = 2 mm, Range = 2.6-9 mm). There was a significant increase of 3.5 mm (t = 10.8, DF = 24, P value = <.0001) in the bile duct diameter post RFA. Five patients presented with pain after the procedure, but only one developed mild post-ERCP pancreatitis and cholecystitis.

CONCLUSIONS

Radiofrequency ablation can be a safe palliation option for unresectable malignant biliary strictures. A multicenter randomized controlled trial is required to confirm the long term benefits of RFA and stenting compared to stenting alone.

Intraductal thermal injury using a heat probe and radiofrequency ablation electrode in a swine model of biliary stenosis

BACKGROUND AND OBJECTIVE

An animal model for bile duct stenosis using intraductal thermal injury has not yet been established. The aims of the current study were to develop biliary stenosis in a swine model by inducing intraductal thermal injury using a heat probe or radiofrequency ablation electrode and to investigate an effective and safe energy dose.

METHODS

Intraluminal thermal injury was applied to the common bile duct with a heat probe in three swines and a radiofrequency ablation electrode in the other three swines by either endoscopic retrograde cholangiography or open laparotomy. Cholangiography and histologic evaluation of common bile duct were taken 2 weeks after thermal injury.

RESULTS

Thermal injury with a heat probe at 25 J for 40 seconds produced a stricture in all three animals. Application of a radiofrequency ablation electrode produced a stricture in two of three animals. An energy dose of 40 W at 80°C for 30 seconds produced biliary stenosis without any complications initially and 2 weeks after thermal injury.

CONCLUSIONS

The application of a heat probe and a radiofrequency ablation electrode for intraductal thermal injury resulted in a reproducible animal model of biliary stenosis.

Endoscopic management of malignant bile duct strictures

Malignant biliary obstruction can arise from intrahepatic, extrahepatic, and hilar locations from either primary or metastatic disease. Biliary-enteric surgical bypass has been surpassed in the last 20 years by endoscopic balloon dilation and stenting. The goal of stenting for biliary decompression is to palliate obstructive symptoms; it has not been shown that survival is affected by stenting alone. Novel endoscopic therapies, including photodynamic therapy and radiofrequency ablation, have been evaluated and show promise. Both therapies seem to be safe and effective in the treatment of malignant bile duct strictures but are in need of prospective studies of longer duration.

Endoscopically applied radiofrequency ablation appears to be safe in the treatment of malignant biliary obstruction

BACKGROUND

In unresectable malignant bile duct obstruction in a patient with a life expectancy longer than 3 months, the use of self-expandable metal stents (SEMSs) is the standard technique to ensure continued biliary drainage. As many as 50% of patients with SEMSs will present with stent occlusion within 6 months. Changes to stent design and composition and concomitant therapy have failed to improve stent patency; therefore, alternative techniques to safely prolong stent patency are required.

OBJECTIVE

To demonstrate the safety of endobiliary bipolar radiofrequency ablation (RFA) in patients with malignant biliary obstruction and to report the 90-day biliary patency of this novel procedure.

DESIGN

Open-label pilot study.

SETTING

Single tertiary care unit.

PATIENTS

A total of 22 patients with unresectable malignant bile duct obstruction.

INTERVENTIONS

Bipolar RFA within the bile duct.

MAIN OUTCOME MEASUREMENTS

Immediate and 30-day complications and 90-day stent patency.

RESULTS

A total of 22 patients (16 pancreatic, 6 cholangiocarcinoma) were recruited between January 2009 and April 2010. Deployment of an RFA catheter was successful in 21 patients. SEMS placement was achieved in all cases of successful RFA catheter deployment. One patient failed to demonstrate successful biliary decompression after SEMS placement and died within 90 days. All other patients maintained stent patency at 30 days. One patient had asymptomatic biochemical pancreatitis, 2 patients required percutaneous gallbladder drainage, and 1 patient developed rigors. At 90-day follow-up, 1 additional patient had died with a patent stent, and 3 patients had occluded biliary stents.

LIMITATIONS

Cohort study.

CONCLUSIONS

Endobiliary RFA treatment appears to be safe. Randomized studies with prolonged follow-up are warranted.