Long-term Outcomes following Resection of Adenocarcinoma Arising from Intraductal Papillary Mucinous Neoplasm (A-IPMN) versus Pancreatic Ductal Adenocarcinoma (PDAC): A Propensity-score Matched Analysis.

OBJECTIVE: The aim of the present study was to compare long-term post-resection oncological outcomes between A-IPMN and PDAC. SUMMARY BACKGROUND DATA: Knowledge of long term oncological outcomes (e.g recurrence and survival data) comparing between adenocarcinoma arising from intraductal papillary mucinous neoplasms (A-IPMN) and pancreatic ductal adenocarcinoma (PDAC) is scarce. METHODS: Patients undergoing pancreatic resection (2010-2020) for A-IPMN were identified retrospectively from 18 academic pancreatic centres and compared with PDAC patients from the same time-period. Propensity-score matching (PSM) was performed and survival and recurrence were compared between A-IPMN and PDAC. RESULTS: 459 A-IPMN patients (median age,70; M:F,250:209) were compared with 476 PDAC patients (median age,69; M:F,262:214). A-IPMN patients had lower T-stage, lymphovascular invasion (51.4%vs. 75.6%), perineural invasion (55.8%vs. 71.2%), lymph node positivity (47.3vs. 72.3%) and R1 resection (38.6%vs. 56.3%) compared to PDAC(P<0.001). The median survival and time-to-recurrence for A-IPMN versus PDAC were 39.0 versus19.5months (P<0.001) and 33.1 versus 14.8months (P<0.001), respectively (median follow-up,78 vs.73 months). Ten-year overall survival for A-IPMN was 34.6%(27/78) and PDAC was 9%(6/67). A-IPMN had higher rates of peritoneal (23.0 vs. 9.1%, P<0.001) and lung recurrence (27.8% vs. 15.6%, P<0.001) but lower rates of locoregional recurrence (39.7% vs. 57.8%; P<0.001). Matched analysis demonstrated inferior overall survival (P=0.005), inferior disease-free survival (P=0.003) and higher locoregional recurrence (P<0.001) in PDAC compared to A-IPMN but no significant difference in systemic recurrence rates (P=0.695). CONCLUSIONS: PDACs have inferior survival and higher recurrence rates compared to A-IPMN in matched cohorts. Locoregional recurrence is higher in PDAC but systemic recurrence rates are comparable and constituted by their own distinctive site-specific recurrence patterns.

Pancreatic exocrine insufficiency after non-pancreatic upper gastrointestinal surgery: meta-analysis.

BACKGROUND: Untreated pancreatic exocrine insufficiency (PEI) results in substantial patient harm. Upper gastrointestinal surgery (bariatric metabolic surgery and oesophagogastric resection) affects the delicate physiology of pancreatic exocrine function and may result in PEI. The aim of this study was to assimilate the literature on incidence, diagnosis, and management of PEI after bariatric metabolic surgery and oesophagogastric resection. METHODS: A systematic review of PubMed, MEDLINE, and Embase databases identified studies investigating PEI after non-pancreatic upper gastrointestinal surgery. Meta-analyses were undertaken for incidence of PEI and benefit of pancreatic enzyme replacement therapy. RESULTS: Among 1620 patients from 24 studies included in quantitative synthesis, 36.0% developed PEI. The incidence of PEI was 23.0 and 50.4% after bariatric metabolic surgery and oesophagogastric resection respectively. Notably, the incidence of PEI was 44% after biliopancreatic diversion with duodenal switch and 66.2% after total gastrectomy. The most common diagnostic test used was faecal elastase 1 (15 of 31 studies), with less than 200 µg/g being diagnostic of PEI. A total of 11 studies considered the management of pancreatic exocrine insufficiency, with 78.6% of patients responding positively to pancreatic enzyme replacement when it was prescribed. CONCLUSION: PEI is common after non-pancreatic upper gastrointestinal surgery and patients may benefit from enzyme replacement therapy.

Pancreatic exocrine insufficiency occurs when enzymes from the pancreas are unable to help digest food. Pancreatic exocrine insufficiency is known to cause disruptive symptoms after gastrointestinal surgery. Although such symptoms are well known after pancreatic surgery, after other gastrointestinal operations, including bariatric metabolic surgery and oesophagogastric cancer resection, pancreatic exocrine insufficiency is often overlooked as a cause of both symptoms and poor nutrition. This study looked at, and combined, all the current evidence on the rate of pancreatic exocrine insufficiency after these operations, the way it is diagnosed, and how it is treated. Pancreatic exocrine insufficiency may be more common than previously thought after bariatric metabolic surgery or oesophagogastric surgery, and clinicians working with these patients should have a low threshold for starting treatment.

Comprehensive, long-term evaluation of pancreatic exocrine insufficiency after pancreatoduodenectomy.

AIMS: Treatment of pancreatic exocrine insufficiency (PEI) following pancreatoduodenectomy (PD) improves quality of life, clinical outcomes, and survival. However, diagnosing PEI following PD is challenging owing to the difficulties with current tests and often non-specific symptoms. This work aims to quantify the true rate of long-term PEI in patients following a PD. METHODS: Patients underwent a PEI screen approximately one to two years following PD for oncologic indication, including the 13C Mixed triglyceride breath test (13CMTGT), faecal elastase 1 (FE-1) and the PEI Questionnaire (PEI-Q). Four reviewers with expertise in PEI reviewed the results blinded to other decisions to classify PEI status; disagreements were resolved on consensus. RESULTS: 26 patients were recruited. Of those with valid test results, these were indicative of PEI based on pre-specified thresholds for 60 % (15/25) for the 13CMTGT, 82 % (18/22) for FE-1, and 88 % (22/25) for the PEI-Q. After discussion between reviewers, the consensus PEI prevalence was 81 % (95 % CI: 61-93 %; 21/26), with 50 % (N = 13) classified as having severe, 23 % (N = 6) moderate, and 8 % (N = 2) mild PEI. DISCUSSION: Since no ideal test exists for PEI, this collation of diagnostic modalities and blinded expert review was designed to ascertain the true rate of long-term PEI following PD. This required our cohort to survive a year, travel to hospital, and undergo a period of starvation and PERT hold, and therefore there is likely to be recruitment bias towards fitter, younger patients with less aggressive pathology. Despite this, over 80 % were deemed to have PEI, with over 90 % of these being considered moderate or severe.

Investigating misdiagnosis of suspected cancer among patients undergoing pancreatoduodenectomy: three decades of experience.

BACKGROUND: Diagnostic error can result in pancreatoduodenectomy (PD) being mistakenly performed for benign disease. The aims of this study were to observe the error rate in PD over three decades and identify characteristics of benign disease that can mimic malignancy. METHODS: Patients with a benign histological diagnosis after having PD performed for suspected malignancy between 1988 and 2019 were selected for review. Preoperative clinical features, imaging and pathological samples were reviewed alongside resection specimens to identify features that may have led to misdiagnosis. RESULTS: Over the study period, 1812 patients underwent PD for suspected malignancy and 97 (5.2 %) of these had a final benign diagnosis. The rate of benign cases reduced across the study period. Some 62 patients proceeded to surgery without a preoperative tissue diagnosis; the decision to operate was made upon clinical and radiologic features alone. There were six patients who had a preoperative pathological sample suspicious for malignancy, of which two had autoimmune pancreatitis in the postoperative histology specimen. DISCUSSION: Benign conditions, notably autoimmune and chronic pancreatitis, can mimic malignancy even with the use of EUS-FNA. The results of all available diagnostic modalities should be interpreted by a multidisciplinary team and honest discussions with the patient should follow.

The impact of the COVID-19 pandemic upon pancreatic cancer treatment (CONTACT Study): a UK national observational cohort study.

INTRODUCTION: CONTACT is a national multidisciplinary study assessing the impact of the COVID-19 pandemic upon diagnostic and treatment pathways among patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: The treatment of consecutive patients with newly diagnosed PDAC from a pre-COVID-19 pandemic cohort (07/01/2019-03/03/2019) were compared to a cohort diagnosed during the first wave of the UK pandemic ('COVID' cohort, 16/03/2020-10/05/2020), with 12-month follow-up. RESULTS: Among 984 patients (pre-COVID: n = 483, COVID: n = 501), the COVID cohort was less likely to receive staging investigations other than CT scanning (29.5% vs. 37.2%, p = 0.010). Among patients treated with curative intent, there was a reduction in the proportion of patients recommended surgery (54.5% vs. 76.6%, p = 0.001) and increase in the proportion recommended upfront chemotherapy (45.5% vs. 23.4%, p = 0.002). Among patients on a non-curative pathway, fewer patients were recommended (47.4% vs. 57.3%, p = 0.004) or received palliative anti-cancer therapy (20.5% vs. 26.5%, p = 0.045). Ultimately, fewer patients in the COVID cohort underwent surgical resection (6.4% vs. 9.3%, p = 0.036), whilst more patients received no anti-cancer treatment (69.3% vs. 59.2% p = 0.009). Despite these differences, there was no difference in median overall survival between the COVID and pre-COVID cohorts, (3.5 (IQR 2.8-4.1) vs. 4.4 (IQR 3.6-5.2) months, p = 0.093). CONCLUSION: Pathways for patients with PDAC were significantly disrupted during the first wave of the COVID-19 pandemic, with fewer patients receiving standard treatments. However, no significant impact on survival was discerned.

Perioperative interventions to reduce pancreatic fistula following pancreatoduodenectomy: meta-analysis.

BACKGROUND: Data on interventions to reduce postoperative pancreatic fistula (POPF) following pancreatoduodenectomy (PD) are conflicting. The aim of this study was to assimilate data from RCTs. METHODS: MEDLINE and Embase databases were searched systematically for RCTs evaluating interventions to reduce all grades of POPF or clinically relevant (CR) POPF after PD. Meta-analysis was undertaken for interventions investigated in multiple studies. A post hoc analysis of negative RCTs assessed whether these had appropriate statistical power. RESULTS: Among 22 interventions (7512 patients, 55 studies), 12 were assessed by multiple studies, and subjected to meta-analysis. Of these, external pancreatic duct drainage was the only intervention associated with reduced rates of both CR-POPF (odds ratio (OR) 0.40, 95 per cent c.i. 0.20 to 0.80) and all-POPF (OR 0.42, 0.25 to 0.70). Ulinastatin was associated with reduced rates of CR-POPF (OR 0.24, 0.06 to 0.93). Invagination (versus duct-to-mucosa) pancreatojejunostomy was associated with reduced rates of all-POPF (OR 0.60, 0.40 to 0.90). Most negative RCTs were found to be underpowered, with post hoc power calculations indicating that interventions would need to reduce the POPF rate to 1 per cent or less in order to achieve 80 per cent power in 16 of 34 (all-POPF) and 19 of 25 (CR-POPF) studies respectively. CONCLUSION: This meta-analysis supports a role for several interventions to reduce POPF after PD. RCTs in this field were often relatively small and underpowered, especially those evaluating CR-POPF.

Long-term outcomes of delayed biliary strictures following cholecystectomy.

BACKGROUND: Delayed biliary strictures (DBS) after cholecystectomy are uncommon and little is known of their aetiology or long-term consequences. The aims of this study were to investigate the clinical and economic impact of DBS after cholecystectomy. METHODS: Patients who developed DBS after cholecystectomy were identified from a prospectively collected and maintained database. Risk factors for stricture development, quality of life (QoL) and long-term biliary complication rates were explored. Costs of treatment and follow up were determined. The same outcomes among patients with minor or major bile duct injury (BDI) were used as a comparison. RESULTS: Among 44 patients, a laparoscopic converted to open procedure or post cholecystectomy bile leak affected some 18 and 12 patients respectively. Most DBS required surgical treatment (40). Over a median follow-up of 8.9 years after DBS treatment, 16 (36%) patients developed biliary complications (similar to minor, 26%, and major BDI, 40%) and 1 patient died of causes related to the biliary stricture. Costs of treating DBS and its follow up (£14,309.26 per patient), were similar to previously reported costs for major BDI (£15,784). CONCLUSION: DBS typically occur after a technically and/or complicated cholecystectomy. Clinical, economic and QoL outcomes are similar to patients with major BDI.

Early oral feeding after pancreatoduodenectomy: a systematic review and meta-analysis.

BACKGROUND: The effect of early oral feeding (EOF) after pancreatoduodenectomy (PD) upon perioperative complications and outcomes is unknown, therefore the aim of this systematic review and meta-analysis was to investigate the effect of EOF on clinical outcomes after PD, such as postoperative pancreatic fistula (POPF), delayed gastric emptying (DGE) and length of stay (LOS). METHODS: A systematic review and meta-analysis was performed in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance and assimilated evidence from studies reporting outcomes for patients who received EOF after PD compared to enteral tube feeding (EN) or parenteral nutrition (PN). RESULTS: Four studies reported outcomes after EOF compared to EN/PN after PD and included 553 patients. Meta-analyses showed no difference in rates of CR-POPF (OR 0.74; 95%CI 0.44-1.24; p = 0.25) or DGE (Grade B/C) (OR 0.83; 95%CI 0.31-2.21; p = 0.70). LOS was significantly shorter in the EOF group compared to the EN/PN group (Mean Difference -3.40 days; 95% -6.11-0.70 days; p = 0.01). CONCLUSION: Current available evidence suggests that EOF after PD is not associated with increased risk of DGE, does not exacerbate POPF and appears to reduce length of stay.

External validation of postoperative pancreatic fistula prediction scores in pancreatoduodenectomy: a systematic review and meta-analysis.

BACKGROUND: Multiple risk scores claim to predict the probability of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy. It is unclear which scores have undergone external validation and are the most accurate. The aim of this study was to identify risk scores for POPF, and assess the clinical validity of these scores. METHODS: Areas under receiving operator characteristic curve (AUROCs) were extracted from studies that performed external validation of POPF risk scores. These were pooled for each risk score, using intercept-only random-effects meta-regression models. RESULTS: Systematic review identified 34 risk scores, of which six had been subjected to external validation, and so included in the meta-analysis, (Tokyo (N=2 validation studies), Birmingham (N=5), FRS (N=19), a-FRS (N=12), m-FRS (N=3) and ua-FRS (N=3) scores). Overall predictive accuracies were similar for all six scores, with pooled AUROCs of 0.61, 0.70, 0.71, 0.70, 0.70 and 0.72, respectively. Considerably heterogeneity was observed, with I2 statistics ranging from 52.1-88.6%. CONCLUSION: Most risk scores lack external validation; where this was performed, risk scores were found to have limited predictive accuracy. . Consensus is needed for which score to use in clinical practice. Due to the limited predictive accuracy, future studies to derive a more accurate risk score are warranted.

Impact of SARS-CoV-2 pandemic on pancreatic cancer services and treatment pathways: United Kingdom experience.

INTRODUCTION: The SARS-CoV-2 pandemic presented healthcare providers with an extreme challenge to provide cancer services. The impact upon the diagnostic and treatment capacity to treat pancreatic cancer is unclear. This study aimed to identify national variation in treatment pathways during the pandemic. METHODS: A survey was distributed to all United Kingdom pancreatic specialist centres, to assess diagnostic, therapeutic and interventional services availability, and alterations in treatment pathways. A repeating methodology enabled assessment over time as the pandemic evolved. RESULTS: Responses were received from all 29 centres. Over the first six weeks of the pandemic, less than a quarter of centres had normal availability of diagnostic pathways and a fifth of centres had no capacity whatsoever to undertake surgery. As the pandemic progressed services have gradually improved though most centres remain constrained to some degree. One third of centres changed their standard resectable pathway from surgery-first to neoadjuvant chemotherapy. Elderly patients, and those with COPD were less likely to be offered treatment during the pandemic. CONCLUSION: The COVID-19 pandemic has affected the capacity of the NHS to provide diagnostic and staging investigations for pancreatic cancer. The impact of revised treatment pathways has yet to be realised.

Does non-operative management of iatrogenic bile duct injury result in impaired quality of life? A systematic review.

BACKGROUND: Several studies have reported the effect of bile duct injury (BDI) on health-related quality of life (HRQOL) with conflicting results. This systematic review aims to study the impact of patient and treatment factors on HRQOL after BDI. METHODS: A search of the PubMed database was performed and studies were reviewed as per the PRISMA guidelines. Selected studies (n = 11) were then divided into two subgroups depending on whether they found HRQOL to be similar or worse between BDI and control groups. Pooled rates of surgical repair and major BDI were calculated for each of these subgroups. RESULTS: Surgical repair rates were 99% (95% CI: 96%-99%) in studies where the BDI patients had similar outcomes to controls, compared to 78% (40%-100%) where their outcomes were significantly worse (p = 0.091). The major BDI rate was 51% (95% CI: 42%-61%) in studies where the BDI patients had similar outcomes to controls, compared to 72% (41%-94%) where their outcomes were significantly worse (p = 0.322). Considerable heterogeneity was present within the two subgroups (I2: 68-99%). DISCUSSION: HRQOL may be adversely affected amongst patients with BDI who do not undergo surgical repair. Significant heterogeneity of data suggests the need for standardised HRQOL tools and injury severity systems when assessing outcomes after BDI.

A comprehensive evaluation of the long-term economic impact of major bile duct injury.

BACKGROUND: Complications and litigation after bile duct injury (BDI) result in clinical and economic burden. The aim of this study was to comprehensively evaluate the long-term clinical and economic impact of major BDI. METHOD: Patients with long-term follow-up after Strasberg E BDI were identified. Costs of treatment and litigation were the primary outcome. Relationships between these outcomes and repair factors, like timing of repair and surgeon expertise, were secondary outcomes. RESULTS: Among 139 patients with a median follow up of 10.7 years, 40% of patients developed biliary complications. Repairs by non-specialist surgeons had significantly higher follow up and treatment costs than those by specialists (£25,814 vs. £14,269, p < 0.001). Estimated litigation costs were higher in delayed than immediate repairs (£23,295 vs. £12,864). As such, the lowest average costs per BDI are after immediate specialist repair and the highest after delayed non-specialist repair (£27,133 vs. £49,109, ×1.81 more costly, p < 0.001). Repair by a non-specialist surgeon (HR: 4.00, p < 0.001) and vascular injury (HR: 2.35, p = 0.013) were significant independent predictors of increased complication rates. CONCLUSION: Costs of major BDI are considerable. They can be reduced by immediate on-table repair by specialist surgeons. This must therefore be considered the standard of care wherever possible.

A comparative study of risk factors for pancreatic fistula after pancreatoduodenectomy or distal pancreatectomy.

BACKGROUND: Evidence associates various biometric and histological variables such as steatosis and absence of fibrosis as risk factors for post-operative pancreatic fistula (POPF) after pancreatoduodenectomy (PD). Following distal pancreatectomy (DP), the association between these factors and POPF is less clear. This study of patients, drawn from the same background population, undergoing PD or DP at a single centre is a comparative study of the risk factors for POPF after these two operations. METHODS: Associations between POPF and patient characteristics, pre-operative blood tests, data from pre-operative computed tomography (CT) imaging, assessment of histological steatosis and fibrosis were explored. RESULTS: 26/107 (24%) and 26/90 (29%) patients developed POPF after PD and DP respectively. Absence of fibrosis was associated with POPF (p < 0.001) after PD and its presence correlated with pancreatic duct width (p < 0.001). Steatosis was not associated with POPF (p = 0.910). Multivariable analysis showed pancreatic duct width (p = 0.016) and fibrosis (p = 0.025) to be independent predictors of POPF after PD. The only variable associated with POPF after DP was underlying pathology (p = 0.005). CONCLUSION: Pancreatic duct width is the most important variable related to POPF after PD and is correlated with fibrosis. Steatosis was not related to POPF. In contrast, after DP POPF appears to be related to the underlying disease.

Involvement of the Gut Microbiome in the Local and Systemic Immune Response to Pancreatic Ductal Adenocarcinoma.

The systemic and local immunosuppression exhibited by pancreatic ductal adenocarcinoma (PDAC) contributes significantly to its aggressive nature. There is a need for a greater understanding of the mechanisms behind this profound immune evasion, which makes it one of the most challenging malignancies to treat and thus one of the leading causes of cancer death worldwide. The gut microbiome is now thought to be the largest immune organ in the body and has been shown to play an important role in multiple immune-mediated diseases. By summarizing the current literature, this review examines the mechanisms by which the gut microbiome may modulate the immune response to PDAC. Evidence suggests that the gut microbiome can alter immune cell populations both in the peripheral blood and within the tumour itself in PDAC patients. In addition, evidence suggests that the gut microbiome influences the composition of the PDAC tumour microbiome, which exerts a local effect on PDAC tumour immune infiltration. Put together, this promotes the gut microbiome as a promising route for future therapies to improve immune responses in PDAC patients.

The microbial composition of pancreatic ductal adenocarcinoma: A systematic review of 16S rRNA gene sequencing.

BACKGROUND: Pancreatic cancer, specifically pancreatic ductal adenocarcinoma (PDAC), continues to pose a significant clinical and scientific challenge. The most significant finding of recent years is that PDAC tumours harbour their specific microbiome, which differs amongst tumour entities and is distinct from healthy tissue. This review aims to evaluate and summarise all PDAC studies that have used the next-generation technique, 16S rRNA gene amplicon sequencing within each bodily compartment. As well as establishing a causal relationship between PDAC and the microbiome. MATERIALS AND METHODS: This systematic review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. A comprehensive search strategy was designed, and 1727 studies were analysed. RESULTS: In total, 38 studies were selected for qualitative analysis and summarised significant PDAC bacterial signatures. Despite the growing amount of data provided, we are not able to state a universal 16S rRNA gene microbial signature that can be used for PDAC screening. This is most certainly due to the heterogeneity of the presentation of results, lack of available datasets and the intrinsic selection bias between studies. CONCLUSION: Several key studies have begun to shed light on causality and the influence the microbiome constituents and their produced metabolites could play in tumorigenesis and influencing outcomes. The challenge in this field is to shape the available microbial data into targetable signatures. Making sequenced data readily available is critical, coupled with the coordinated standardisation of data and the need for consensus guidelines in studies investigating the microbiome in PDAC.

Resection of isolated liver oligometastatic disease in pancreatic ductal adenocarcinoma: Is there a survival benefit? A systematic review.

BACKGROUND: Presence of liver metastatic disease in pancreatic ductal adenocarcinoma (PDAC), either synchronous or metachronous after pancreatic resection, is a terminal diagnosis that warrants management with palliative intent as per all international practice guidelines. However, there is an increasing interest on any potential value of surgical treatment of isolated oligometastatic disease in selected cases. AIM: To present the published evidence on surgical management of PDAC liver metastases, synchronous and metachronous, and compare the outcomes of these treatments to the current standard of care. METHODS: A systematic review was performed in line with the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines to compare the outcomes of both synchronous and metachronous liver metastases resection to standard care. RESULTS: 356 studies were identified, 31 studies underwent full-text review and of these 10 were suitable for inclusion. When synchronous resection of liver metastases was compared to standard care, most studies did not demonstrate a survival benefit with the exception of one study that utilised neoadjuvant treatment. However, resection of metachronous disease appeared to confer a survival advantage when compared to treatment with chemotherapy alone. CONCLUSION: A survival benefit may exist in resection of selected cases of metachronous liver oligometastatic PDAC disease, after disease biology has been tested with time and systemic treatment. Any survival benefit is less clear in synchronous cases; however an approach with neoadjuvant treatment and consideration of resection in some selected cases may confer some benefit. Future studies should focus on pathways for selection of cases that may benefit from an aggressive approach.

Ursodeoxycholic acid in the management of symptomatic gallstone disease: systematic review and clinician survey.

BACKGROUND: Symptomatic gallstones are common. Ursodeoxycholic acid (UDCA) is a bile acid that dissolves gallstones. There is increasing interest in UDCA for symptomatic gallstones, particularly in those unfit for surgery. METHOD: A UK clinician survey of use and opinions about UDCA in symptomatic gallstones was performed, assessing clinicians' beliefs and perceptions of UDCA effectiveness. A systematic review was performed in accordance with the PRISMA guidelines. PubMed, MEDLINE, and Embase databases were searched for studies of UDCA for symptomatic gallstones (key terms included 'ursodeoxycholic acid'; 'UDCA'; 'biliary pain'; and 'biliary colic'). Information was assessed by two authors, including bias assessment, with independent review of conflicts. RESULTS: Overall, 102 clinicians completed the survey, and 42 per cent had previous experience of using UDCA. Survey responses demonstrated clinical equipoise surrounding the benefit of UDCA for the management of symptomatic gallstones, with no clear consensus for benefit or non-benefit; however, 95 per cent would start using UDCA if there was a randomized clinical trial (RCT) demonstrating a benefit. Eight studies were included in the review: four RCTs, three prospective studies, and one retrospective study. Seven of eight studies were favourable of UDCA for biliary pain. Outcomes and follow-up times were heterogenous, as well as comparator type, with only four of eight studies comparing with placebo. CONCLUSION: Evidence for UDCA in symptomatic gallstones is scarce and heterogenous. Clinicians currently managing symptomatic gallstone disease are largely unaware of the benefit of UDCA, and there is clinical equipoise surrounding the benefit of UDCA. Level 1 evidence is required by clinicians to support UDCA use in the future.