British Society of Gastroenterology guidelines on sedation in gastrointestinal endoscopy.

Over 2.5 million gastrointestinal endoscopic procedures are carried out in the United Kingdom (UK) every year. Procedures are carried out with local anaesthetic r with sedation. Sedation is commonly used for gastrointestinal endoscopy, but the type and amount of sedation administered is influenced by the complexity and nature of the procedure and patient factors. The elective and emergency nature of endoscopy procedures and local resources also have a significant impact on the delivery of sedation. In the UK, the vast majority of sedated procedures are carried out using benzodiazepines, with or without opiates, whereas deeper sedation using propofol or general anaesthetic requires the involvement of an anaesthetic team. Patients undergoing gastrointestinal endoscopy need to have good understanding of the options for sedation, including the option for no sedation and alternatives, balancing the intended aims of the procedure and reducing the risk of complications. These guidelines were commissioned by the British Society of Gastroenterology (BSG) Endoscopy Committee with input from major stakeholders, to provide a detailed update, incorporating recent advances in sedation for gastrointestinal endoscopy.This guideline covers aspects from pre-assessment of the elective 'well' patient to patients with significant comorbidity requiring emergency procedures. Types of sedation are discussed, procedure and room requirements and the recovery period, providing guidance to enhance safety and minimise complications. These guidelines are intended to inform practising clinicians and all staff involved in the delivery of gastrointestinal endoscopy with an expectation that this guideline will be revised in 5-years' time.

EUS-guided choledochoduodenostomy with electrocautery-enhanced lumen-apposing metal stents in patients with malignant distal biliary obstruction: multicenter collaboration from the United Kingdom and Ireland.

BACKGROUND AND AIMS: EUS-guided choledochoduodenostomy (EUS-CDD) with an electrocautery-enhanced lumen-apposing metal stent (EC-LAMS) has emerged as a viable method of establishing biliary drainage in patients with malignant distal biliary obstruction (MDBO). Our aim was to assess the efficacy, safety, and outcomes in patients with MDBO who underwent EUS-CDD with an EC-LAMS. METHODS: A retrospective review of consecutive patients with MDBO who underwent EUS-CDD with EC-LAMSs at 8 tertiary institutions across the United Kingdom and Ireland between September 2016 and November 2020 was undertaken. RESULTS: One hundred twenty patients (55% men) with a median age of 73 years (interquartile range, 17; range, 43-94) were included. The median follow-up period in 117 patients was 70 days (interquartile range, 169; range, 3-869), and 23 patients (19.2%) were alive at the end of the follow-up. Three patients were lost to follow-up. Technical success was achieved in 109 patients (90.8%). Clinical success (reduction of serum bilirubin to ≤50% of original value within 14 days) was achieved in 94.8% of patients (92/97). The adverse event rate was 17.5% (n = 21). Biliary reintervention after initial technical success was required in 9 patients (8.3%). CONCLUSIONS: EUS-CDD with EC-LAMSs at tertiary institutions within a regional hepatopancreatobiliary network for treatment of MDBO was effective in those where ERCP was not possible or was unsuccessful. When technical failures or adverse events occur, most patients can be managed with conservative or endoscopic therapy.

Rate of pancreatic cancer following a negative endoscopic ultrasound and associated factors.

BACKGROUND : Data are limited regarding pancreatic cancer diagnosed following a pancreaticobiliary endoscopic ultrasound (EUS) that does not diagnose pancreatic cancer. We have studied the frequency of, and factors associated with, post-EUS pancreatic cancer (PEPC) and 1-year mortality. METHODS : Between 2010 and 2017, patients with pancreatic cancer and a preceding pancreaticobiliary EUS were identified in a national cohort using Hospital Episode Statistics. Patients with a pancreaticobiliary EUS 6-18 months before a later pancreatic cancer diagnosis were the PEPC cases; controls were those with pancreatic cancer diagnosed within 6 months of pancreaticobiliary EUS. Multivariable logistic regression models examined the factors associated with PEPC and a Cox regression model examined factors associated with 1-year cumulative mortality. RESULTS : 9363 pancreatic cancer patients were studied; 93.5 % identified as controls (men 53.2 %; median age 68 [interquartile range (IQR) 61-75]); 6.5 % as PEPC cases (men 58.2 %; median age 69 [IQR 61-77]). PEPC was associated with older age (≥ 75 years compared with < 65 years, odds ratio [OR] 1.42, 95 %CI 1.15-1.76), increasing co-morbidity (Charlson co-morbidity score > 5, OR 1.90, 95 %CI 1.49-2.43), chronic pancreatitis (OR 3.13, 95 %CI 2.50-3.92), and diabetes mellitus (OR 1.58, 95 %CI 1.31-1.90). Metal biliary stents (OR 0.57, 95 %CI 0.38-0.86) and EUS-FNA (OR 0.49, 95 %CI 0.41-0.58) were inversely associated with PEPC. PEPC was associated with a higher cumulative mortality at 1 year (hazard ratio 1.12, 95 %CI 1.02-1.24), with only 14 % of PEPC patients (95 %CI 12 %-17 %) having a surgical resection, compared with 21 % (95 %CI 20 %-22 %) of controls. CONCLUSIONS : PEPC occurred in 6.5 % of patients and was associated with chronic pancreatitis, older age, more co-morbidities, and specifically diabetes mellitus. PEPC was associated with a worse prognosis and lower surgical resection rates.

SARS-CoV-2 infection in acute pancreatitis increases disease severity and 30-day mortality: COVID PAN collaborative study.

OBJECTIVE: There is emerging evidence that the pancreas may be a target organ of SARS-CoV-2 infection. This aim of this study was to investigate the outcome of patients with acute pancreatitis (AP) and coexistent SARS-CoV-2 infection. DESIGN: A prospective international multicentre cohort study including consecutive patients admitted with AP during the current pandemic was undertaken. Primary outcome measure was severity of AP. Secondary outcome measures were aetiology of AP, intensive care unit (ICU) admission, length of hospital stay, local complications, acute respiratory distress syndrome (ARDS), persistent organ failure and 30-day mortality. Multilevel logistic regression was used to compare the two groups. RESULTS: 1777 patients with AP were included during the study period from 1 March to 23 July 2020. 149 patients (8.3%) had concomitant SARS-CoV-2 infection. Overall, SARS-CoV-2-positive patients were older male patients and more likely to develop severe AP and ARDS (p<0.001). Unadjusted analysis showed that SARS-CoV-2-positive patients with AP were more likely to require ICU admission (OR 5.21, p<0.001), local complications (OR 2.91, p<0.001), persistent organ failure (OR 7.32, p<0.001), prolonged hospital stay (OR 1.89, p<0.001) and a higher 30-day mortality (OR 6.56, p<0.001). Adjusted analysis showed length of stay (OR 1.32, p<0.001), persistent organ failure (OR 2.77, p<0.003) and 30-day mortality (OR 2.41, p<0.04) were significantly higher in SARS-CoV-2 co-infection. CONCLUSION: Patients with AP and coexistent SARS-CoV-2 infection are at increased risk of severe AP, worse clinical outcomes, prolonged length of hospital stay and high 30-day mortality.

Fork-tip needle biopsy versus fine-needle aspiration in endoscopic ultrasound-guided sampling of solid pancreatic masses: a randomized crossover study.

BACKGROUND: A novel fork-tip fine-needle biopsy (FNB) needle has recently been introduced for endoscopic ultrasound (EUS)-guided sampling. The aim of this study was to compare the performance of fork-tip FNB histology and standard fine-needle aspiration (FNA) cytology in the diagnosis of solid pancreatic masses. METHODS: A randomized crossover study was performed in patients referred for EUS-guided sampling. Three passes were taken with each needle in a randomized order. Only samples reported as diagnostic of malignancy were considered positive. The primary end point was the sensitivity of diagnosis of malignancy. Secondary end points included the amount of sample obtained, ease of diagnosis, duration of tissue sampling, pathologist viewing time, and cost. RESULTS: 108 patients were recruited. Median age was 69 years (range 30 - 87) and 57 were male; 85.2 % had a final diagnosis of malignancy. There were statistically significant differences in sensitivity (82 % [95 % confidence interval (CI) 72 % to 89 %] vs. 71 % [95 %CI 60 % to 80 %]), accuracy (84 % [95 %CI 76 % to 91 %] vs. 75 % [95 %CI 66 % to 83 %]), proportion graded as a straightforward diagnosis (69 % [95 %CI 60 % to 78 %] vs. 51 % [95 %CI 41 % to 61 %]), and median pathology viewing time (188 vs. 332 seconds) (P < 0.001) between FNB and FNA needles, respectively. There was no significant difference in cost between an FNB or FNA strategy. CONCLUSION: The diagnostic performance of the fork-tip FNB needle was significantly better than that of FNA; it was associated with ease of diagnosis, shorter pathological viewing times, and was cost neutral.

Impact of metal and plastic stents on endoscopic ultrasound-guided aspiration cytology and core histology of head of pancreas masses.

BACKGROUND: Stents are frequently placed in patients with biliary obstruction due to a mass in the head of the pancreas. The impact of plastic or self-expandable metal stents (SEMSs) on endoscopic ultrasound (EUS)-guided tissue sampling is unclear. This study aimed to assess, using strict pathological criteria, whether stents impair fine-needle aspiration (FNA) or fine-needle biopsy (FNB). METHODS: All patients with a solid mass in the head of the pancreas who underwent EUS-guided tissue sampling between 2010 and 2016 at our unit were included. Factors with possible impact on diagnostic performance were analyzed using logistic regression. Analysis was performed using both strict (malignant only) and less strict (suspicious for malignancy) cutoffs. RESULTS: Of 631 individuals undergoing 698 procedures, 535 (84.8 %) had a final diagnosis of malignancy, 141 had SEMS, 149 had plastic stents, and 341 had no stent. Using strict criteria, SEMS were associated with an increased occurrence of incorrect diagnosis of EUS tissue sampling, with an odds ratio (OR) of 1.96 (95 % confidence interval [CI] 1.24 - 3.10). Increasing tumor size (OR 0.72, 95 %CI 0.59 - 0.87), increasing number of passes (OR 0.84, 95 %CI 0.72 - 0.99), and fork-tip biopsy needle (OR 0.52, 95 %CI 0.31 - 0.86) were independently associated with a decrease in incorrect diagnosis. Repeat tissue sampling was more common with SEMSs (10.2 %) than with plastic stents (2.9 %) or no stents (4.5 %) (P < 0.02). CONCLUSION: SEMS use had a negative impact on tissue diagnosis in pancreatic head masses, whereas use of a fork-tip biopsy needle and increasing number of passes were independently associated with improved accuracy.

Comparison of the diagnostic performance of 2 core biopsy needles for EUS-guided tissue acquisition from solid pancreatic lesions.

BACKGROUND AND AIMS: A new core biopsy needle with a novel tip, opposing bevel, and sheath design has recently been introduced for EUS-guided fine-needle biopsy (FNB). The diagnostic utility of this needle for differentiating solid pancreatic masses is currently unknown. The aim of this study was to compare the diagnostic performance and yield for tissue acquisition from solid pancreatic lesions of the opposing bevel needle with those of a reverse bevel EUS-FNB needle. METHODS: Consecutive patients with solid pancreatic masses undergoing EUS-FNB using the opposing bevel (n = 101) and the reverse bevel (n = 100) core biopsy needles were included in the study. Final diagnosis was based on positive histology or at least 12 months of follow-up in cases with a negative biopsy. The primary outcome was the diagnostic performance of the 2 needles for malignant pancreatic masses. A secondary outcome was the diagnostic yield. RESULTS: Compared with the reverse bevel needle, using strict criteria the opposing bevel needle provided significantly higher sensitivity (71.1% vs 90.1%; P = .0006) and overall accuracy (74% vs 92%; I = 0.0006) for discriminating malignant from benign solid pancreatic masses. The proportion of samples classified as adequate for histologic analysis was 87% for the reverse bevel needle versus 99% for the opposing bevel needle (p = 0.002) Multivariate analysis controlling the needle gauge and site did not show any significant difference in accuracy and sensitivity between the 2 groups. There were no adverse events in either group. CONCLUSIONS: In this first, large, single-center preliminary cohort study, an EUS core biopsy needle with a novel tip, opposing bevel, and sheath design afforded substantially superior tissue yield and diagnostic performance compared with a reverse-bevel needle. If replicated by randomized controlled trials, our findings suggest that similarly designed needles could become the standard of care for EUS-guided tissue acquisition from solid pancreatic masses.

Derivation, validation, and comparison of a new prognostic scoring system for acute lower gastrointestinal bleeding.

Objectives: Lower gastrointestinal bleeding is a common presentation with little data concerning risk factors for adverse outcomes. The aim was to derive and validate a scoring system to stratify risk in lower gastrointestinal bleeding and compare it to the Oakland score. Methods: A total of 2385 consecutive patients (mean age 65 years, 1140 males) were used to derive the score using multivariate logistic regression modeling then internally and externally validated. The Oakland score was applied and area under receiver operating characteristic (AUROC) curves were calculated and compared. A score of <1 was compared with an Oakland score of <9 to assess 30-day rebleeding and mortality rates. Results: Rebleeding was associated with age, inpatient bleeding, syncope, malignancy, tachycardia, hypotension, lower hemoglobin and mortality with age, inpatient bleeding, liver/gastrointestinal disease, tachycardia, and hypotension. The area under the receiver operating characteristic curves was 0.742 for rebleeding and 0.802 for mortality. A score <1 was associated with rebleeding (0.0%-2.2%) and mortality (0%). The Oakland score had a significantly lower area under the receiver operating characteristic curve for rebleeding of 0.687 but not for mortality; 0.757. A score <1 was associated with a lower 30-day rebleeding risk compared to an Oakland score <9 (4/379 vs. 15/355, p = 0.009) but not mortality (0/365 vs. 1/355, p = 0.493). Conclusions: Our score predicts 30-day rebleeding and mortality rate with low scores associated with very low risk. The Aberdeen score is superior to the Oakland score for predicting rebleeding. Prospective evaluation of both scores is required.

Mortality among patients who receive or defer gastrostomies.

BACKGROUND & AIMS: There are few data on outcomes and mortality of patients who have received gastrostomies. We assessed 30-day and 1-year mortalities of patients in the United Kingdom who were referred to hospitals for gastrostomies and of patients who deferred this intervention. METHODS: We collected data from 1327 patients referred to 2 hospitals in Sheffield, United Kingdom, for gastrostomies from February 2004 through May 2010. Data were analyzed to determine 30-day and 1-year mortalities. Predicted mortality by using the validated Sheffield Gastrostomy Scoring System (SGSS) was then compared with actual mortality by using area under the receiver operator curves to determine levels of agreement in patients referred for gastrostomy. RESULTS: Three hundred four patients (23%) did not undergo gastrostomy after multidisciplinary team discussion, which was based on physicians' recommendations. This group had 35.5% mortality at 30 days and 74.3% at 1 year, whereas mortality among patients who underwent gastrostomy (n = 1027) was 11.2% at 30 days and 41.1% at 1 year (P < .0001, compared with patients who deferred the procedure). The area under the receiver operator curves for the SGSS demonstrated acceptable agreement between predicted and actual mortality in patients who underwent or were deferred gastrostomy. CONCLUSIONS: On the basis of data from 1327 patients, those who undergo gastrostomy have significantly lower mortality than those who defer the procedure. Without applying the SGSS, clinicians are able to select patients most likely to benefit from gastrostomy. The SGSS could provide objective support to clinicians involved in making ethically contentious or potentially litigious decisions.

Does on-site adequacy assessment by cytotechnologists improve results of EUS guided FNA of solid pancreaticobiliary lesions?

CONTEXT: Rapid onsite adequacy assessment is stated to improve the diagnostic performance of EUS-FNA. OBJECTIVES: The aim of this study was to establish if the introduction of adequacy assessment performed by a biomedical scientist (cytotechnologist) to an established EUS service improved the diagnostic accuracy of EUS guided FNA of solid pancreaticobiliary lesions. DESIGN AND PATIENTS: This retrospective study includes all patients with solid pancreaticobiliary lesions who underwent EUS-FNA from April 2009 to September 2010. An in room cytotechnologist was present for 2 out of the 4 weekly EUS lists and therefore there were two groups identified: Group 1, cytotechnologist absent; and Group 2, cytotechnologist present. RESULTS: There were 82 patients in Group 1 and 97 patients in Group 2. There was no statistically significant difference in the number of passes (4.1 vs. 4.3), the inadequate aspirate rate (7.3% vs. 5.1%) or the mean size of the lesions (34.7 vs. 32.6 mm) between the groups. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value in Group 1 were 89%, 88%, 100%, 100% and 50% respectively. The results in Group 2 were 91%, 90%, 100%, 100% and 69% respectively. There was no statistically significant difference between the two groups. CONCLUSIONS: In this study the adequacy assessment performed by a cytotechnologist did not improve the diagnostic accuracy of EUS-FNA. In an established EUS-FNA service with low inadequate aspirate rates, onsite adequacy assessment may not improve results of the test.

Pancreaticobiliary versus head and neck presentation of immunoglobulin G4-related disease: different sides of the same coin?

BACKGROUND AND STUDY AIM: Immunoglobulin G4-related disease (IgG4-RD) is a rare immune mediated fibroinflammatory condition. Pancreaticobiliary (PB) and head and neck (HN) are two of the most commonly involved anatomical sites. It has been postulated that PB IgG4-RD and HN IgG4-RD have distinct clinical phenotypes. Whether the optimum treatment regimen or response to therapy differs between them is unknown. We aimed to assess differences between PB and HN IgG4-RD in a cohort of IgG4 disease managed by an IgG4-RD multispecialty team. METHODS: We performed a retrospective study of a prospectively maintained multidisciplinary IgG4-RD database to identify patients diagnosed with PB and HN IgG4-RD (based on initial presentation) between 2005 and 2019. The electronic patient records were reviewed. Use of immunosuppressive agents and clinical course was analysed. RESULTS: 60 patients with PB IgG4-RD and 14 with HN IgG4-RD were included in the study. PB IgG4-RD was associated with older age at diagnosis 64 versus 51 years (p<0.001), higher serum IgG4 level as a multiple of upper limit of normal median (IQR) 2 (1-3.75) vs 1 (1-2), (p=0.04) and greater proportion with more than one organ involved 68% vs 33% (p=0.03). HN IgG4-RD was more likely to receive second-line therapy 71% versus 36% (p=0.03). Persistent elevation of serum IgG4 after therapy was more common in PB IgG4-RD 84% versus 43% (p=0.03). CONCLUSION: These findings support the contention that PB IgG4-RD and HN IgG4-RD have different clinical profiles and represent distinct subtypes of IgG4-RD.

Endoscopic Ultrasound-Guided Gallbladder Drainage for Malignant Biliary Obstruction: A Systematic Review.

BACKGROUND: Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) is a rescue technique for patients with malignant biliary obstruction who fail conventional treatment with ERCP or EUS-guided biliary drainage. The technique has been successfully employed in the management of acute cholecystitis in patients not fit for surgery. However, the evidence for its use in malignant obstruction is less robust. This review article aims to evaluate the data available at present to better understand the safety and efficacy of EUS-guided gallbladder drainage. METHODS: A detailed literature review was conducted and several databases were searched for any studies relating to EUS-GBD in malignant biliary obstruction. Pooled rates with 95% confidence intervals were calculated for clinical success and adverse events. RESULTS: Our search identified 298 studies related to EUS-GBD. The final analysis included 7 studies with 136 patients. The pooled rate of clinical success (95% CI) was 85% (78-90%, I2: 0%). The pooled rate of adverse events (95% CI) was 13% (7-19%, I2: 0%). Adverse events included: peritonitis, bleeding, bile leakage, stent migration, and stent occlusion. No deaths directly related to the procedure were reported; however, in some of the studies, deaths occurred due to disease progression. CONCLUSION: This review supports the use of EUS-guided gallbladder drainage as a rescue option for patients who have failed conventional measures.

Are we missing pancreatic exocrine insufficiency in 'at-risk' groups? Prospective assessment of the current practice and yield of faecal elastase testing in patients with diabetes mellitus, HIV and/or high alcohol intake.

There is cumulative evidence that pancreatic exocrine insufficiency (PEI) is under-recognised and can occur in patients with 'at-risk' conditions. Thus, we aimed to assess the current practice and yield of requesting faecal elastase (FEL-1), an indicator of PEI, in patients with 'at-risk' conditions. We prospectively recruited patients attending secondary care clinics with diabetes mellitus (DM), people living with HIV (PLHIV) and inpatients admitted to hospital with high alcohol intake (HAI). All patients underwent testing with FEL-1. Those patients with PEI (FEL-1 <200 µg/g) were contacted and offered a follow-up review in gastroenterology clinic. In total, 188 patients were recruited (HAI, n=78; DM, n=64; and PLHIV, n=46). Previous FEL-1 testing had not been performed in any of the patients. The return rate of samples was 67.9% for patients with HAI, 76.6% for those with DM and 56.5% for those with PLHIV. The presence of PEI was shown in 20.4% of patients with DM, 15.4% of patients with PLHIV and 22.6% in those with HAI. Diarrhoea and bloating were the most reported symptoms in followed-up patients with low FEL-1 (31.8% and 22.7% of patients, respectively). Follow-up computed tomography (CT) scans in those patients with PEI identified chronic pancreatitis changes in 13.6% and pancreatic atrophy in 31.8% of patients. These results suggest that there is a lack of testing for PEI in 'at-risk' groups. Our findings also suggest that using FEL-1 to test for PEI in patients with DM, PLHIV and HAI has a significant impact, although further studies are required to validate these findings.

Bacterial contamination of endoscopist and assistant face visors during gastrointestinal endoscopy: a pilot study.

Background and aim: During the COVID-19 pandemic, health workers' facial exposure to pathogens has been brought into focus. In this study, we aimed to determine the occurrence and degree of facial contamination to both endoscopists and their assistants during endoscopic procedures to help inform future safety measures. Methods: Non-sterile visors worn by endoscopist, assistant and room control visors from 50 procedures were swabbed post procedure for culture. Procedure type, therapy, duration and evidence of visible visor contamination were recorded. After 48-hour incubation, all bacterial colonies were identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Organisms were classified into skin/environmental, oronasal and enteric. Results: A total of 104 visors were available for assessment (93 staff; 11 control). In worn visors, skin/environmental flora were isolated from 70, oronasal flora from 8, and enteric flora from 3 with an average colony count of >9.5. Notably, bacteria of enteric origin (Escherichia coli and Enterobacter cloacae) were isolated from three worn visors. In room control, skin/environmental flora were isolated from seven and oronasal flora from one with average colony count of five. No room control visors grew enteric flora. Overall, 9.1% room control and 10.8% worn visors were contaminated with organisms that could possibly have originated from patients. However, enteric flora were only obtained from worn visors. No visors were visibly contaminated. Conclusion: This pilot study demonstrates risk of contamination to faces of endoscopists and assistants. Larger studies are required to determine degree of risk and to give guidance on facial protection during gastrointestinal endoscopy.

Clinical and cost effectiveness of endoscopic bipolar radiofrequency ablation for the treatment of malignant biliary obstruction: a systematic review.

Background: Early evidence suggests that using radiofrequency ablation as an adjunct to standard care (i.e. endoscopic retrograde cholangiopancreatography with stenting) may improve outcomes in patients with malignant biliary obstruction. Objectives: To assess the clinical effectiveness, cost-effectiveness and potential risks of endoscopic bipolar radiofrequency ablation for malignant biliary obstruction, and the value of future research. Data sources: Seven bibliographic databases, three websites and seven trials registers were searched from 2008 until 21 January 2021. Review methods: The study inclusion criteria were as follows: patients with biliary obstruction caused by any form of unresectable malignancy; the intervention was reported as an endoscopic biliary radiofrequency ablation to ablate malignant tissue that obstructs the bile or pancreatic ducts, either to fit a stent (primary radiofrequency ablation) or to clear an obstructed stent (secondary radiofrequency ablation); the primary outcomes were survival, quality of life or procedure-related adverse events; and the study design was a controlled study, an observational study or a case report. Risk of bias was assessed using Cochrane tools. The primary analysis was meta-analysis of the hazard ratio of mortality. Subgroup analyses were planned according to the type of probe, the type of stent (i.e. metal or plastic) and cancer type. A de novo Markov model was developed to model cost and quality-of-life outcomes associated with radiofrequency ablation in patients with primary advanced bile duct cancer. Insufficient data were available for pancreatic cancer and secondary bile duct cancer. An NHS and Personal Social Services perspective was adopted for the analysis. A probabilistic analysis was conducted to estimate the incremental cost-effectiveness ratio for radiofrequency ablation and the probability that radiofrequency ablation was cost-effective at different thresholds. The population expected value of perfect information was estimated in total and for the effectiveness parameters. Results: Sixty-eight studies (1742 patients) were included in the systematic review. Four studies (336 participants) were combined in a meta-analysis, which showed that the pooled hazard ratio for mortality following primary radiofrequency ablation compared with a stent-only control was 0.34 (95% confidence interval 0.21 to 0.55). Little evidence relating to the impact on quality of life was found. There was no evidence to suggest an increased risk of cholangitis or pancreatitis, but radiofrequency ablation may be associated with an increase in cholecystitis. The results of the cost-effectiveness analysis were that the costs of radiofrequency ablation was £2659 and radiofrequency ablation produced 0.18 quality-adjusted life-years, which was more than no radiofrequency ablation on average. With an incremental cost-effectiveness ratio of £14,392 per quality-adjusted life-year, radiofrequency ablation was likely to be cost-effective at a threshold of £20,000 per quality-adjusted life-year across most scenario analyses, with moderate uncertainty. The source of the vast majority of decision uncertainty lay in the effect of radiofrequency ablation on stent patency. Limitations: Only 6 of 18 comparative studies contributed to the survival meta-analysis, and few data were found concerning secondary radiofrequency ablation. The economic model and cost-effectiveness meta-analysis required simplification because of data limitations. Inconsistencies in standard reporting and study design were noted. Conclusions: Primary radiofrequency ablation increases survival and is likely to be cost-effective. The evidence for the impact of secondary radiofrequency ablation on survival and of quality of life is limited. There was a lack of robust clinical effectiveness data and, therefore, more information is needed for this indication. Future work: Future work investigating radiofrequency ablation must collect quality-of-life data. High-quality randomised controlled trials in secondary radiofrequency ablation are needed, with appropriate outcomes recorded. Study registration: This study is registered as PROSPERO CRD42020170233. Funding: This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 7. See the NIHR Journals Library website for further project information.

The bile and pancreatic ducts transport fluids to the intestines to help people digest their food properly. Some types of cancer can cause these ducts to become totally or partially blocked. We wanted to know if endoscopic radiofrequency ablation is safe and works well to treat people who have one of these blockages that cannot be removed by surgery. Radiofrequency ablation burns away a blockage by hitting it with radio waves. Endoscopic means that the radio waves are directed to the blockage using a thin, tube-like wire with a camera at the end. During radiofrequency ablation, a person might have a small tube called a stent put into their bile or pancreatic duct to keep it open or to replace an already blocked stent.

We searched for research studies that looked at (1) whether or not radiofrequency ablation was able to remove blockages from the ducts, (2) if radiofrequency ablation allowed people to live longer, (3) if patients had a better quality of life after radiofrequency ablation, (4) if radiofrequency ablation caused any side effects and (5) how much it costs to treat people with radiofrequency ablation.

We found that treatment with radiofrequency ablation before giving a person a stent helped them to live a little longer with their cancer. We did not find any evidence that radiofrequency ablation increased pain or swelling in the bile duct or pancreatic duct. Radiofrequency ablation might cause more swelling in the gall bladder than having a stent without radiofrequency ablation, but there was not enough research available for us to be certain of this.

Radiofrequency ablation before inserting a stent could be a safe option to add to treatment of bile and pancreatic duct blockages caused by cancer. There is limited research evidence and so we are unable to recommend radiofrequency ablation as a treatment for standard clinical practice.