Endoscopic radiofrequency biliary ablation treatment: A comprehensive review

Endoscopic treatment for early duodenal papillary carcinoma: long-term outcomes

BACKGROUND AND AIM

This study aims to determine whether endoscopic papillectomy (EP) is a safe and effective treatment for early duodenal papillary carcinoma with long-term follow-up.

METHODS

From June 2012 to September 2022, 48 patients with early duodenal papilloma carcinoma who received endoscopic treatment were included. The histological types, percentage of complete resections, postoperative residuals, adverse events, and recurrences were evaluated.

RESULTS

EP was successful in all patients; 46 were lumped, and two were fragmented, with a 95.8% intact removal rate (46/48). The preoperative biopsy pathological positive rate was 70.8% (34/48). The incidence of early postoperative adverse events (within 1 month after EP) were 16.7% (8/48), including four cases of acute pancreatitis, three cases of delayed bleeding, and one case of acute cholangitis. In addition, 4.2% (2/48) of the late adverse events were bile duct stenosis. After 6 months, the postoperative residual rate was 0%. The median time to recurrence was 17.5 months, and the postoperative recurrence rate was 16.7% (8/48) in patients treated with radiofrequency ablation. The median progression-free survival was 18.6 months (95% CI, 12.1-25.1), and the median overall survival was 121.5 months (95% CI, 105.6-120.9).

CONCLUSIONS

EP is a safe and efficient alternative therapy for early duodenal papillary carcinoma. Endoscopic follow-up and treatment are essential because of the potential for recurrence.

British Society of Gastroenterology guidelines for the diagnosis and management of cholangiocarcinoma

These guidelines for the diagnosis and management of cholangiocarcinoma (CCA) were commissioned by the British Society of Gastroenterology liver section. The guideline writing committee included a multidisciplinary team of experts from various specialties involved in the management of CCA, as well as patient/public representatives from AMMF (the Cholangiocarcinoma Charity) and PSC Support. Quality of evidence is presented using the Appraisal of Guidelines for Research and Evaluation (AGREE II) format. The recommendations arising are to be used as guidance rather than as a strict protocol-based reference, as the management of patients with CCA is often complex and always requires individual patient-centred considerations.

Radiofrequency ablation via an implanted self-expandable metallic stent to treat in-stent restenosis in a rat gastric outlet obstruction model

Background: In-stent restenosis caused by tissue hyperplasia and tumor growth through the wire meshes of an implanted self-expandable metallic stent (SEMS) remains an unresolved obstacle. This study aimed to investigate the safety and efficacy of SEMS-mediated radiofrequency ablation (RFA) for treating stent-induced tissue hyperplasia in a rat gastric outlet obstruction model. Methods: The ablation zone was investigated using extracted porcine liver according to the ablation time. The optimal RFA parameters were evaluated in the dissected rat gastric outlet. We allocated 40 male rats to four groups of 10 rats as follows: group A, SEMS placement only; group B, SEMS-mediated RFA at 4 weeks; group C, SEMS-mediated RFA at 4 weeks and housed until 8 weeks; and group D, SEMS-mediated RFA at 4 and 8 weeks. Endoscopy and fluoroscopy for in vivo imaging and histological and immunohistochemical analysis were performed to compare experimental groups. Results: Stent placement and SEMS-mediated RFA with an optimized RFA parameter were technically successful in all groups. Granulation tissue formation-related variables were significantly higher in group A than in groups B-D (all p < 0.05). Endoscopic and histological findings confirmed that the degrees of stent-induced tissue hyperplasia in group D were significantly lower than in groups B and C (all p < 0.05). Hsp70 and TUNEL expressions were significantly higher in groups B-D than in group A (all p < 0.001). Conclusion: The implanted SEMS-mediated RFA successfully managed stent-induced tissue hyperplasia, and repeated or periodic RFA seems to be more effective in treating in-stent restenosis in a rat gastric outlet obstruction model.

Unconventional treatment of inoperable biliary IPMN with an oesophageal stent in the common bile duct: case report

Biliary intraductal papillary mucinous neoplasm (IPMN) is a rare biliary neoplasia preferably treated with oncologic resection. Endoscopic radio frequency (RF) ablation may be used as a palliative measure. We present a rare case, where heavy co-morbidities prevented surgery. Continuous mucus production caused recurrent episodes of severe cholangitis. Several ERCPs (endoscopic retrograde cholangio pancretography) were necessary due to recurrent biliary obstruction. RF ablation was not effective in the dilated common bile duct without a stricture. Standard biliary stents failed due to either migration or occlusion. When other options failed, an exceptional decision was made: a covered large diameter oesophageal stent was inserted in ERCP into the bile duct to secure bile flow and stop mucus production. Digital cholangioscopy was crucial adjunct to standard ERCP in endoscopic management. The palliative treatment method was successful: there were no stent-related adverse events or readmissions for cholangitis. The follow-up in the palliative care lasted until patient's last 10 months of lifetime.

[The first Russian experience of radiofrequency ablation in the treatment of adenoma of the major duodenal papilla with intraductal growth in the common bile duct]

Adenoma of the major duodenal papilla can cause bile flow blockade and obstructive jaundice. We present successful endoscopic radiofrequency ablation for adenoma of the major duodenal papilla with intraductal growth in the common bile duct.

Endobiliary and Pancreatic Radiofrequency Ablations

Radio frequency ablation (RFA) involves use of thermal energy to perform ablation of tissues. It has a wide range of application in gastrointestinal tract. Over the last few years, several studies have reported successful and safe application in the biliary and pancreatic tissues. It is particularly beneficial in patients with biliary malignancies in whom it has shown to improve survival. Additionally, it can be applied in occluded metal stents secondary to tumor ingrowth to prolong the patency of stents. In pancreas, RFA can successfully ablate cystic lesions and neuroendocrine tumors. It has also been applied in unresectable pancreatic cancers. This review discusses the application of endobiliary and pancreatic RFAs.

Endoscopic management of benign and malignant hilar stricture

Management of hilar strictures pose a significant challenge for endoscopists. Several strategies have been demonstrated in the last decade beyond decompression, however, there remains controversy and minimal consensus in the literature. This review seeks to summarize the current literature and discuss emerging therapies, such as photodynamic therapy and radiofrequency ablation.

Endobiliary Radiofrequency Ablation Using a Short-Type Balloon Enteroscope in Patients with Surgically Altered Anatomy

BACKGROUND

Endoscopic radiofrequency ablation (RFA) is expected to prolong stent patency for malignant biliary obstruction (MBO). However, its feasibility when used in conjunction with a balloon enteroscope (BE) in patients with surgically altered anatomy (SAA) remains unknown.

AIMS

This study aimed to investigate the feasibility of RFA combined with metal stent insertion under BE guidance for MBO in patients with SAA.

METHODS

Thirty-seven patients who underwent treatment between October 2016 and January 2021 and met the eligibility criteria were investigated retrospectively. Study outcomes included technical and clinical success, recurrent biliary obstruction (RBO), and other adverse events besides RBO associated with RFA with metal stent placement using BE.

RESULTS

Technical and clinical success rates were 100% (37/37) each. The rates of early and late adverse events were 8.1% (3/37) and 8.1% (3/37), respectively. RBO occurred in 32.4% (12/37) of the patients, and the median time to RBO was 296 days. The cause of RBO was ingrowth in eight patients, overgrowth in three patients, and indeterminate in one patient. All reinterventions for RBO were successful using the BE approach; all ingrowths, except one, were recanalized using additional RFA without additional stent placement. The frequency of reintervention-related adverse events was 9.1% (1/11). The median time to RBO after reintervention was 166 days.

CONCLUSIONS

This study demonstrated the technical safety and feasibility as well as good long-term outcomes of endobiliary RFA combined with metal stent placement under BE guidance. This approach may be a useful option for treating MBO in patients with SAA.

Comparing palliative treatment options for cholangiocarcinoma: photodynamic therapy vs. radiofrequency ablation

Referral to an endoscopist is often done once curative resection is no longer an option for cholangiocarcinoma management. In such cases, palliation has become the main objective of the treatment. Photodynamic therapy and radiofrequency ablation can be performed to achieve palliation, with both procedures associated with improved stent patency and survival. Despite the greatly increased cost and association with photosensitivity, photodynamic therapy allows transmission to the entire biliary tree. In contrast, radiofrequency ablation is cheaper and faster to apply, but requires intraductal contact. This paper reviews both modalities and compares their efficacy and safety for bile duct cancer palliation.

Palliation in Gallbladder Cancer: The Role of Gastrointestinal Endoscopy

Gallbladder cancer is a rare malignancy burdened by poor prognosis with an estimated 5-year survival of 5% to 13% due to late presentation, early infiltration of surrounding tissues, and lack of successful treatments. The only curative approach is surgery; however, more than 50% of cases are unresectable at the time of diagnosis. Endoscopy represents, together with surgery and chemotherapy, an available palliative option in advanced gallbladder cancers not eligible for curative treatments. Cholangitis, jaundice, gastric outlet obstruction, and pain are common complications of advanced gallbladder cancer that may need endoscopic management in order to improve the overall survival and the patients’ quality of life. Endoscopic biliary drainage is frequently performed to manage cholangitis and jaundice. ERCP is generally the preferred technique allowing the placement of a plastic stent or a self-expandable metal stent depending on the singular clinical case. EUS-guided biliary drainage is an available alternative for patients not amenable to ERCP drainage (e.g., altered anatomy). Gastric outlet obstruction is another rare complication of gallbladder malignancy growing in contact with the duodenal wall and causing its compression. Endoscopy is a less invasive alternative to surgery, offering different options such as an intraluminal self-expandable metal stent or EUS-guided gastroenteroanastomosis. Abdominal pain associated with cancer progression is generally managed with medical treatments; however, for incoercible pain, EUS-guided celiac plexus neurolysis has been described as an effective and safe treatment. Locoregional treatments, such as radiofrequency ablation (RFA), photodynamic therapy (PDT), and intraluminal brachytherapy (IBT), have been described in the control of disease progression; however, their role in daily clinical practice has not been established yet. The aim of this study is to perform a review of the literature in order to assess the role of endoscopy and the available techniques in the palliative therapy of advanced gallbladder malignancy.

Various innovative roles for 3-Fr microcatheters in pancreaticobiliary endoscopy

With the development of newer devices and technical innovations, pancreaticobiliary endoscopy is expanding to assume more advanced therapeutic roles. As with other devices, slimmed-down "3-Fr microcatheters" are considered to be opening new windows toward entirely new therapeutic techniques for various purposes. Our practical experience with a total of 34 consecutive patients in whom 3-Fr microcatheters were applied during pancreaticobiliary endoscopic procedures clarified the potential roles of this instrument in pancreaticobiliary endoscopy. The major benefits of 3-Fr microcatheters involve their slimness and flexibility. Applications of 3-Fr microcatheters could be categorized into three groups according to the characteristics of usage: (1) utilization as a cannulation catheter for peroral digital cholangioscopy (n = 15); (2) selective advancement through deep flexures or severely stenotic ducts (n = 11); or (3) two-devices-in-one-channel technique (n = 8). The microcatheter worked successfully for cannulation of cholangioscopy in all but one case (14/15, 93.3%). For selective advancement, the microcatheter worked for troubleshooting in 9 of 11 cases (81.8%). With the two-devices-in-one-channel technique, the microcatheter proved satisfactory in all cases (8/8, 100%). In total, the microcatheter was successfully maneuvered in 31 of 34 cases (91.1%), following the failure of procedures using conventional endoscopic techniques. In terms of adverse events, cystic duct injury was only observed in two cases (5.8%), who recovered under conservative observation, because its slimness could minimize the damage. We believe that 3-Fr microcatheters offer effective and safe salvage troubleshooting during various endoscopic pancreaticobiliary procedures that face troublesome situations with conventional strategies.

Peroral cholangioscopy: Update on the state-of-the-art

Peroral cholangioscopy (POC) is an endoscopic procedure that allows direct intraductal visualization of the biliary tract. POC has emerged as a vital tool for indeterminate biliary stricture evaluation and treatment of difficult biliary stones. Over several generations of devices, POC has fulfilled additional clinical needs where other diagnostic or therapeutic modalities have been inadequate. With adverse event rates comparable to standard endoscopic retrograde cholangioscopy and unique technical attributes, the role of POC is likely to continue expand. In this frontiers article, we highlight the existing and growing clinical applications of POC as well as areas of ongoing research.

Silver Nanofunctionalized Stent after Radiofrequency Ablation Suppresses Tissue Hyperplasia and Bacterial Growth

Intraductal radiofrequency (RF) ablation combined with placement of a self-expandable metal stent (SEMS) for malignant biliary obstruction has risks such as stent- and heat-induced biliary sludge and restenosis. Here, we investigated the efficacy of a silver nanoparticles (AgNPs)-coated SEMS to inhibit tissue hyperplasia and bacterial growth caused by RF ablation with stent placement in the rabbit bile duct. The release behavior and antibacterial effects of AgNPs-coated SEMSs were evaluated. Then, SEMSs were successfully placed in all rabbits immediately after RF ablation. Ag ions were rapidly released at the beginning and then showed a gradual release behavior. The AgNPs-coated SEMS significantly inhibited bacterial activity compared to the uncoated SEMS (p < 0.05). Cholangiography and histological examination confirmed that the level of tissue hyperplasia was significantly lower in the AgNPs group than in the control group (all p < 0.05). Immunohistochemistry analyses revealed that TUNEL-, HSP 70-, and α-SMA-positive areas were significantly lower in the AgNPs group than in the control group (all p < 0.05). Intraductal RF ablation combined with nanofunctionalized stent placement represents a promising new approach for suppressing thermal damage as well as stent-induced tissue hyperplasia and bacterial growth.

Radiofrequency ablation in the management of primary hepatic and biliary tumors

In the United States, 80%-90% of primary hepatic tumors are hepatocellular carcinomas and 10%-15% are cholangiocarcinomas (CCA), both with high mortality rate, particularly CCA, which portends a worse prognosis. Traditional management with surgery has good outcomes in appropriately selected patients; however, novel ablative treatment options have emerged, such as radiofrequency ablation (RFA), which can improve the prognosis of both hepatic and biliary tumors. RFA is aimed to generate an area of necrosis within the targeted tissue by applying thermal therapy via an electrode, with a goal to completely eradicate the tumor while preserving surrounding healthy tissue. Role of RFA in management of hepatic and biliary tumors forms the focus of our current mini-review article.

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.

Ablative therapies of the biliary tree

Cholangiocarcinoma, a malignancy of the epithelial cells in the intrahepatic or extrahepatic biliary tree, is often diagnosed at later stages. Median survival duration ranges from 3 to 9 months with a less than ten percent 5-year survival rate. Thus, often treatment strategies are aimed more towards palliation instead of cure. With the majority of patients presenting with unresectable disease at the time of diagnosis, surgical intervention is not feasible, making less invasive endoscopic therapies more suitable. Initially, biliary stents were utilized for biliary decompression to mitigate cholestatic symptoms and prevent cholangitis; however, this strategy did not prove to provide significant survival benefit. Therefore, efforts to treat the tumor burden itself in addition to maintaining biliary patency became a focus of innovation and research in the endoscopic field. This study has led to the advent of therapies such as photodynamic therapy, radiofrequency ablation, and intraluminal brachytherapy. These options combined with biliary stenting have shown to not only offer the benefit of biliary decompression, but also to potentially improve stent patency and survival. Further, there is an anti-tumor effect of each of these modalities, portending an additional benefit in this subset of patients. Despite numerous retrospective and prospective studies assessing these ablative therapies, there is still a paucity of appropriately powered randomized controlled trials, and further research has yet to be done in the field. This review details the current literature entailing endobiliary ablative strategies.

Tips and tricks for the diagnosis and management of biliary stenosis-state of the art review

Biliary stenosis may represent a diagnostic and therapeutic challenge resulting in a delay in diagnosis and initiation of therapy due to the frequent difficulty in distinguishing a benign from a malignant stricture. In such cases, the diagnostic flowchart includes the sequential execution of imaging techniques, such as magnetic resonance, magnetic resonance cholangiopancreatography, and endoscopic ultrasound, while endoscopic retrograde cholangiopancreatography is performed to collect tissue for histopathological/cytological diagnosis or to treat the stenosis by insertion of stent. The execution of percutaneous transhepatic drainage with subsequent biopsy has been shown to increase the possibility of tissue diagnosis after failure of the above techniques. Although the diagnostic yield of histopathology and imaging has increased with improvements in endoscopic ultrasound and peroral cholangioscopy, differential diagnosis between malignant and benign stenosis may not be easy in some patients, and strictures are classified as indeterminate. In these cases, a multidisciplinary workup including biochemical marker assays and advanced technologies available may speed up a diagnosis of malignancy or avoid unnecessary surgery in the event of a benign stricture. Here, we review recent advancements in the diagnosis and management of biliary strictures and describe tips and tricks to increase diagnostic yields in clinical routine.

Endoscopic papillectomy for ampullary adenomatous lesions: A literature review

Ampullary adenomatous lesions of the gastrointestinal tract are rare and can be asymptomatic. Therefore, ampullary adenomas with malignant potential require prompt removal, regardless of whether they are adenomatous or carcinomatous lesions. Endoscopic papillectomy is a safe and effective alternative therapy to surgery to treat duodenal papillary lesions in selected patients. Accurate preoperative diagnosis and staging of ampullary adenomatous lesions are critical for predicting prognosis and determining the most appropriate therapeutic approach. Furthermore, the management and prevention of adverse events and endoscopic treatment for remnant or recurrent lesions and surveillance are essential for successful endoscopic management of ampullary adenomatous lesions. This literature review was based on PubMed and MEDLINE and focused on recent advancements in the endoscopic papillectomy technique to provide a comprehensive view of endoscopic papillectomy to treat ampullary adenomatous lesions.

Development of Radiofrequency Ablation Generator and Balloon-Based Catheter for Microendoluminal Thin-Layer Ablation Therapy Using the Rat Duodenum as a Model of Low-Impedance Tissue

Radiofrequency ablation (RFA) is a routinely used, safe, and effective method for the tissue destruction. Often, in case of its application in malignant conditions, the extent of tissue destruction is insufficient due to the size of the target lesion, as well as due to the risk of heat-induced damage to the surrounding organs. Nevertheless, there are conditions requiring superficial precise-depth ablation with preservation of deeper layers. These are represented, for example, by mucosal resurfacing in case of Barrett's esophagus or treatment of recurrent mucosal bleeding in case of chronic radiation proctitis. Recently, new indications for intraluminal RFA use emerged, especially in the pancreatobiliary tract. In the case of intraductal use of RFA (e.g., biliary and pancreatic tract), there are currently available rigid and needle tip catheters. An expandable balloon-based RFA catheter suitable for use in such small-diameter tubular organs could be of benefit due to possible increase of contact between the probe and the target tissue; however, to prevent excessive tissue damage, a compatible generator suitable for low-impedance catheter/tissue is essential. This project aimed to develop a radiofrequency ablation generator and bipolar balloon-based catheter optimized for the application in the conditions of low-impedance tissue and (micro)endoluminal environment. Subsequent evaluation of biological effect in vivo was performed using duodenal mucosa in Wistar rat representing conditions of endoluminal radiofrequency ablation of low-impedance tissue. Experiments confirming the safety and feasibility of RFA with our prototype devices were conducted.

The Status and Development of Oral Choledochoscopy Diagnosis and Treatment of Biliary Tract Diseases

Choledochoscopy technology has realized the direct observation of bile duct lesions, and can be loaded with a variety of special accessories to perform the corresponding diagnosis and treatment operations, and has become an important means for the diagnosis of unexplained bile duct stricture and treatment of refractory bile duct stones. With the further enhancement of the imaging quality and operability, the clinical application of choledochoscopy has gradually expanded to the precise positioning of cholangiocarcinoma before surgical resection, the drainage of the gallbladder through the nipple, the removal of the displaced bile duct stent and other fields. This paper briefly reviewed the historical evolution of choledochoscopy and reviewed the latest clinical advances of oral choledochoscopy in the diagnosis and treatment of biliary tract diseases.

An Acceptor-π-Donor Structured Organic Chromophore for NIR Triggered Thermal Ablation of Tumor via DNA Damage-Mediated Apoptosis

Introduction

It will be challenging to develop high-performance organic chromophores for light-triggered thermal ablation of the tumor. Besides, the mechanisms of organic chromophores for tumor therapy remain unclear. Herein, an acceptor-π-donor (A-π-D) structured organic chromophore based on 2-dicyanomethylenethiazole named PTM was developed for photothermal therapy (PTT) of tumors.

Methods and Results

Biocompatible PTM nanoparticles (PTM NPs) were fabricated by enclosing PTM with Pluronic F-127. The results of optical and photothermal properties of PTM NPs showed robust near-infrared (NIR) absorption, excellent photostability and high photothermal conversion efficiency (56.9%). The results of flow cytometry, fluorescence microscopy, apoptosis, CCK-8 assays and animal experiments showed that PTM NPs had a good killing effect on tumors under NIR laser irradiation. Furthermore, mechanistic studies, RNA-seq and biological analysis revealed that PTM NPs can cause tumor cell death via DNA damage-mediated apoptosis.

Conclusion

Light-induced thermal ablation effects of PTM NPs in vitro and vivo were surveyed. Collectively, our studies provided a new approach to developing a safe and effective photothermal agent for cancer treatment.

Endoscopic Ultrasound-Guided Antegrade Radiofrequency Ablation and Metal Stenting With Hepaticoenterostomy for Malignant Biliary Obstruction: A Prospective Preliminary Study

Endobiliary radiofrequency ablation (RFA) for malignant biliary obstruction is a promising option for improving biliary stent patency, but its efficacy and safety with endoscopic ultrasound (EUS)-guided biliary drainage are uncertain. We examined the feasibility of EUS-guided hepaticoenterostomy with antegrade stenting (EUS-HEAS) and RFA in patients with unresectable malignant biliary obstruction.

Feasibility of balloon-based endobiliary radiofrequency ablation under cholangioscopy guidance in a swine model

Although endobiliary radiofrequency ablation (RFA) has demonstrated considerable potential for the treatment of biliary strictures, conventional catheter RFA has several limitations. This study aimed to evaluate the feasibility of a novel cholangioscopy (CS)-guided balloon-based RFA procedure in vivo using a swine model. CS-guided balloon-RFA was performed under endoscopic retrograde cholangiography guidance at target temperatures of 60 ℃ or 70 ℃, which were maintained for 60 s. We evaluated the technical feasibility, adverse events, and histological effects associated with the procedure. Twelve sites were ablated in seven miniature pigs. The CS-guided balloon-RFA procedure was technically successful in all cases without any hindrance. Mucosal changes could be detected during RFA, and the ablation area was identified on CS. Necropsy was performed in four pigs on the same day as the procedure: the tissue samples showed coagulative necrosis, and the entire internal circumference of the bile duct was uniformly ablated. The mean lengths of the ablation area in the samples ablated at 60 °C and 70 °C were 20.64 and 22.18 mm, respectively, while the mean depths were 3.46 and 5.07 mm, respectively. The other three pigs were reared and euthanized and autopsied 35 days after the procedure. The site to be ablated had replaced the granulation tissue and fibrotic changes. No adverse events were observed in any case. CS-guided balloon-RFA appears to be a promising option for treating biliary strictures. This preliminary study could pave the way for the evaluation of this procedure in future human clinical trials.

Endoscopic papillectomy for ampullary adenoma and early adenocarcinoma: Analysis of factors related to treatment outcome and long-term prognosis

OBJECTIVES

There are few reports on the long-term prognosis of papillary tumors after endoscopic papillectomy. Here, we report a retrospective study of the therapeutic effects, long-term prognosis, and affecting factors.

METHODS

The inclusion criteria were papillary adenoma with/without an adenocarcinoma component on biopsy results and ≤10 mm intraductal extension, and the exclusion criteria were moderate to poorly differentiated adenocarcinoma on biopsy results. If no residual lesion was confirmed ≥6 months after the last endoscopic treatment, remission was defined. Subsequently, follow-up endoscopy was scheduled once a year. Surgery was required in the case of adenocarcinoma recurrence or intraductal lesions >10 mm. The rates of adverse events, remission, recurrence, and need for surgery were examined. The affecting factors were calculated.

RESULTS

There were a total of 253 subjects, including 65 with adenocarcinoma. Pancreatitis (7.5%), bleeding (9.1%) and perforation (2.8%) were observed as adverse events. Among 221 subjects with ≥6 months of follow-up, 212 (95.9%) were in remission. The cumulative recurrence rate using the Kaplan-Meier analysis at 5 years was 16.9% (22 cases), with the need for surgery in 5.9% (5 cases). Intraductal extension on preoperative diagnosis was the only significant risk factor for both recurrence (P < 0.001) and the need for surgery (P = 0.005). The presence of adenocarcinoma had no significant effect.

CONCLUSION

Although remission was achieved in more than 95% of our patients, we observed a high rate of recurrence at the long-term follow-up, which was significantly associated with intraductal extension but not with the presence of adenocarcinoma.

Evaluating the tissue effects of balloon-based endobiliary radiofrequency ablation in porcine bile ducts

BACKGROUND

We developed a novel balloon-based endobiliary radiofrequency ablation (RFA) system to overcome the limitations of conventional RFA in treating malignant biliary strictures. This study aimed to evaluate the histological effects of balloon-RFA in porcine bile ducts.

METHODS

Balloon-RFA of intrahepatic bile ducts from freshly resected porcine livers was performed for 60 s at 50, 60 and 70 °C. The specimens were subsequently sectioned for histological analysis and the slides were digitally scanned. Pseudo-coloring was applied based on the intensity of the ablation effect, and the area and estimated volume of ablation were measured.

RESULTS

All samples showed epithelial sloughing and coagulative necrosis, and the entire internal circumference of the bile duct was evenly ablated. Complete transmural necrosis and involvement beyond the wall were found in 0% of samples ablated at 50 °C, in 33% at 60 °C and 100% at 70 °C. The mean depth and estimated volume of the ablation areas were 1.29 mm and 353.84 mm³, 1.44 mm, and 505.54 mm³ and 1.81 mm and 702.52 mm³ at 50, 60 and 70 °C, respectively.

CONCLUSIONS

Balloon-RFA leads to sloughing of the mucosa and coagulative necrosis. Ablation depth and volume increased in proportion to target temperature.

The Safety of Radiofrequency Ablation Using a Novel Temperature-Controlled Probe for the Treatment of Residual Intraductal Lesions after Endoscopic Papillectomy

Background/Aims

Treatment of residual intraductal lesions after endoscopic papillectomy for ampullary adenomas is relatively difficult. Few studies have been conducted using intraductal radiofrequency ablation (RFA) in the treatment of such lesions, and no study has aimed to reduce the side effects of excessive heat caused by RFA. Recently, a temperature-controlled RFA probe was developed to avoid excessive heat. This study aimed to investigate the safety of this new RFA probe in the treatment of intraductal lesions of ampullary adenoma.

Methods

Patients who received RFA for residual intraductal lesions after endoscopic papillectomy between November 2017 and June 2019 were retrospectively reviewed. A novel temperature- controlled probe (ELRA) was used for intraductal RFA, and clinical data including adverse events were collected.

Results

Ten patients were included in this study. Intraductal adenomas showed low-grade dysplasia in eight patients and high-grade dysplasia in two patients. The median diameter of intraductal adenomas was 9 mm (range, 5 to 10 mm) in the common bile duct and 5 mm (range, 4 to 11 mm) in the pancreatic duct. Adverse events occurred in three patients (30.0%), of which two were mild pancreatitis and one was asymptomatic biliary stricture. Over a median follow-up period of 253 days, only one patient underwent additional surgery, as the remainder showed no adenomatous lesions on follow-up biopsies.

Conclusions

The new temperature-controlled RFA probe can be used with acceptable safety for the treatment of residual intraductal lesions after endoscopic papillectomy. Further evaluation through future prospective studies is needed.

Personalized Endoscopy in Complex Malignant Hilar Biliary Strictures

Malignant hilar biliary obstruction (HBO) represents a complex clinical condition in terms of diagnosis, surgical and medical treatment, endoscopic approach, and palliation. The main etiology of malignant HBO is hilar cholangiocarcinoma that is considered an aggressive biliary tract's cancer and has still today a poor prognosis. Endoscopy plays a crucial role in malignant HBO from the diagnosis to the palliation. This technique allows the collection of cytological or histological samples, direct visualization of the suspect malignant tissue, and an echoendoscopic evaluation of the primary tumor and its locoregional staging. Because obstructive jaundice is the most common clinical presentation of malignant HBO, endoscopic biliary drainage, when indicated, is the preferred treatment over the percutaneous approach. Several endoscopic techniques are today available for both the diagnosis and the treatment of biliary obstruction. The choice among them can differ for each clinical scenario. In fact, a personalized endoscopic approach is mandatory in order to perform the proper procedure in the singular patient.

Efficacy and safety of radiofrequency ablation in patients with unresectable malignant biliary strictures

INTRODUCTION

previous studies have shown that endoscopic radiofrequency ablation in unresectable biliary duct tumors prolongs survival.

METHODS

this was an observational study of patients with an unresectable malignant stricture. The aim was to evaluate survival, stent patency and adverse events of radiofrequency compared with a matched control group.

RESULTS

the study included 40 patients, 12 with radiofrequency. There were no differences between baseline parameters in both groups. The survival time was longer in the radiofrequency group with no statistically significant difference (217 vs 129 days, log-rank 0.31). There was no difference in stent permeability or adverse events.

CONCLUSION

the radiofrequency group had a three-month increase in survival, which did not reach statistical significance.

Novel balloon catheter-based endobiliary radiofrequency ablation system: Ex-vivo experimental study

BACKGROUND

Endobiliary radiofrequency ablation (RFA) is a promising treatment option for malignant biliary obstruction, but conventional catheter RFA (Conventional-RFA) has several limitations. We examined the feasibility of a novel approach to balloon-based RFA (Balloon-RFA) with an automatic temperature control system in freshly resected pig livers.

METHODS

Balloon-RFA application was performed in a step-by-step manner at target temperatures of 50°C, 60°C, and 70°C. The temperatures were maintained for 60 s. As a control, Conventional-RFA was performed at 7 W of power for 90 s, 7 W 120 s, 10 W 90 s, and 10 W 120 s. The ablation areas were measured and compared between Balloon-RFA and Conventional-RFA.

RESULTS

The maximum ablation depths in Balloon-RFA were 1.86 ± 0.53, 2.29 ± 0.31, and 3.19 ± 0.47 mm at target temperatures of 50, 60, and 70°C, respectively. The maximum ablation depths in Conventional-RFA were 2.81 ± 0.46, 4.09 ± 0.45, 3.41 ± 0.58, and 4.27 ± 0.29 mm at 7 W 90 s, 7 W 120 s, 10 W 90 s, and 10 W 120 s, respectively. Differences between the minimum and maximum depths were significantly smaller in Balloon-RFA (0.73 ± 0.31 mm) than in Conventional-RFA (2.00 ± 0.62 mm; P < 0.001). Excessive ablation occurred only in Conventional-RFA (0% vs. 67%; P = 0.005).

CONCLUSIONS

The novel balloon-based RFA system allows ablation to be finely tuned in order to successfully obtain consistent ablation depths and avoid excessive ablation.

Long-term outcomes of a long, partially covered metal stent for EUS-guided hepaticogastrostomy in patients with malignant biliary obstruction (with video)

BACKGROUND AND AIMS

We previously reported safety and effectiveness of EUS-guided hepaticogastrostomy (EUS-HGS) using a long, partially covered metal stent (LP-CMS) for malignant biliary obstruction (MBO). In this study, we aimed to evaluate long-term outcomes of EUS-HGS in an expanded cohort.

METHODS

One hundred ten patients undergoing EUS-HGS using an LP-CMS in 2 centers were retrospectively studied. Technical and functional success, adverse events, recurrent biliary obstruction (RBO), and reinterventions were evaluated.

RESULTS

The cause of MBO was pancreatic cancer in 50%, and the location of MBO was distal in 68%. The stent length was 8 cm in 2%, 10 cm in 84%, and 12 cm in 15%, with a median intragastric stent length of 54 mm. Technical and functional success rates were 100% and 94%, respectively. The adverse event rate was 25% (mild 15%, moderate 7%, severe 3%), but about one-half of adverse events were mild transient fever and abdominal pain. RBO developed in 33%, with a median cumulative time to RBO of 6.3 months. The major cause of RBO was hyperplasia at an uncovered portion. The presence of prior biliary drainage and short intragastric stent length were significantly associated with RBO. Reintervention for RBO was successfully achieved through the EUS-HGS route in 92%. The remaining reintervention procedures were 1 EUS-HGS and 2 percutaneous transhepatic biliary drainage all in cases with hilar MBO.

CONCLUSIONS

EUS-HGS using an LP-CMS for unresectable MBO was safe and effective. RBO was not uncommon, but reintervention through the EUS-HGS route was technically possible in most cases.

New Devices for Endoscopic Treatments in Gastroenterology: A Narrative Review

Endoscopy is in a period of continuous innovations in terms of image quality, endoscopes, post-processing software and lastly, application of Artificial Intelligence. Therapeutic boundaries have expanded, widening the grey zone between endoscopy and surgery, and increasing endoscopic approaches in clinical scenarios where, until a few years ago, surgery was the only option. New scopes and accessories have made it easier to access critical areas such as the biliary tree and the small bowel intestine. In the field of hepato-pancreato-biliary endoscopy (HPB), it is now possible to directly access the biliary ducts or cystic lesions though dedicated stents and scopes, rather than having to rely only on fluoroscopy and ultrasound, increasing the diagnostic and therapeutic options by applying a three-dimensional approach. This narrative review will give an overview of some of the most relevant emerging fields in luminal and HPB endoscopy, highlighting advantages and main limitations of the techniques, and providing considerations for future development.

Nonsurgical Approaches to Treat Biliary Tract and Liver Tumors

Endoscopic and percutaneous therapies have been shown to prolong life and reduce morbidity for patients with unresectable advanced stages of primary hepatobiliary malignancies. This article reviews pertinent studies published within the last 5 years that involve locoregional techniques to manage hepatocellular carcinoma, perihilar and distal cholangiocarcinoma. A major emphasis is placed on photodynamic therapy, radiofrequency ablation, irreversible electroporation, and microwave ablation. Technical advances, combinational therapies, and postintervention outcomes are discussed. Despite widespread application, high-quality evidence does not show superiority of any particular locoregional technique for treating advanced hepatobiliary cancers.