Systematic review and meta-analysis of survival outcomes in T2a and T2b gallbladder cancers

BACKGROUND

The 8th edition of AJCC TNM staging of Gallbladder cancer subdivided T2 stage into T2a and T2b based on tumour location. This meta-analysis aimed to investigate the long-term outcomes in T2a and T2b gallbladder cancers.

METHODS

Literature search of Medline, Web of science, Embase and Cochrane databases was performed. Study characteristics, survival and recurrence data were extracted for meta-analysis of effect estimates and of individual patient data.

RESULTS

Fifteen retrospective studies (2531 patients, T2a = 1332, T2b = 199) were included in the meta-analysis. Overall survival (OS) was significantly worse in patients with T2b compared to T2a tumours (HR 2.18, 95% CI 1.67-2.86, p < 0.0001). Meta-analysis of individual patient data (n = 629) showed similar results (HR 1.92, 95% CI 1.43-2.58, p < 0.00001). Patients with T2b tumours had higher risk of recurrence compared to T2a (OR 3.19, 95% CI 1.40-7.28, p = 0.006) and were more likely to receive adjuvant chemotherapy (OR 1.76, 95% CI 1.12-2.84, p = 0.014). Liver resection improved OS in T2b tumours (HR 2.99, CI 1.73-5.16, p < 0.0001).

CONCLUSION

T2b gallbladder tumours have worse overall survival and increase risk of recurrence compared to T2a. Liver resection appears to improve OS in patients with T2b tumours. However, high quality multicenter data is required to confirm these results.

Prevalence and prognosis of increased pancreatic enzymes in patients with COVID-19: A systematic review and meta-analysis

INTRODUCTION

The prevalence of increased pancreatic enzymes (elevated serum amylase and/or lipase) and its relationship to clinical outcomes in patients with coronavirus disease 2019 (COVID-19) infection is not known.

METHODS

A systematic review and meta-analysis of relevant studies reporting prevalence and impact of increased pancreatic enzymes (defined as an elevation in amylase and/or lipase levels above the upper limit of normal [ULN] value) in COVID-19 was undertaken.

RESULTS

A total of 36,496 patients from 21 studies were included for this meta-analysis. The overall prevalence and mortality for increased pancreatic enzymes (>ULN) in COVID-19 were 25.4% (95% CI, 15.8%-36.2%) and 34.6% (95% CI, 25.5%-44.4%), respectively. The overall prevalence and mortality for increased pancreatic enzymes (>3 × ULN) were 6.1% (95% CI, 3.6%-9.2%) and 39.2% (95% CI, 18.7%-61.6%), respectively. Patients with increased pancreatic enzymes, including elevated serum lipase or amylase of either type, had worse clinical outcomes, including need for ICU admission, mechanical ventilation and mortality.

DISCUSSION

Increased pancreatic enzymes is frequent and may exacerbate the consequences of COVID-19 infection.

COVID-19 and liver cancer: lost patients and larger tumours

BACKGROUND

Northern England has been experiencing a persistent rise in the number of primary liver cancers, largely driven by an increasing incidence of hepatocellular carcinoma (HCC) secondary to alcohol-related liver disease and non-alcoholic fatty liver disease. Here we review the effect of the COVID-19 pandemic on primary liver cancer services and patients in our region.

OBJECTIVE

To assess the impact of the COVID-19 pandemic on patients with newly diagnosed liver cancer in our region.

DESIGN

We prospectively audited our service for the first year of the pandemic (March 2020-February 2021), comparing mode of presentation, disease stage, treatments and outcomes to a retrospective observational consecutive cohort immediately prepandemic (March 2019-February 2020).

RESULTS

We observed a marked decrease in HCC referrals compared with previous years, falling from 190 confirmed new cases to 120 (37%). Symptomatic became the the most common mode of presentation, with fewer tumours detected by surveillance or incidentally (% surveillance/incidental/symptomatic; 34/42/24 prepandemic vs 27/33/40 in the pandemic, p=0.013). HCC tumour size was larger in the pandemic year (60±4.6 mm vs 48±2.6 mm, p=0.017), with a higher incidence of spontaneous tumour haemorrhage. The number of new cases of intrahepatic cholangiocarcinoma (ICC) fell only slightly, with symptomatic presentation typical. Patients received treatment appropriate for their cancer stage, with waiting times shorter for patients with HCC and unchanged for patients with ICC. Survival was associated with stage both before and during the pandemic. 9% acquired COVID-19 infection.

CONCLUSION

The pandemic-associated reduction in referred patients in our region was attributed to the disruption of routine healthcare. For those referred, treatments and survival were appropriate for their stage at presentation. Non-referred or missing patients are expected to present with more advanced disease, with poorer outcomes. While protective measures are necessary during the pandemic, we recommend routine healthcare services continue, with patients encouraged to engage.

Impact of prior biliary stenting on diagnostic performance of endoscopic ultrasound for mesenteric vascular staging in patients with head of pancreas and periampullary malignancy

Objective

The diagnostic performance of endoscopic ultrasound (EUS) for stratification of head of pancreas and periampullary tumours into resectable, borderline resectable and locally advanced tumours is unclear as is the effect of endobiliary stents. The primary aim of the study was to assess the diagnostic performance of EUS for resectability according to stent status.

Design

A retrospective study was performed. All patients presenting with a solid head of pancreas mass who underwent EUS and surgery with curative intent during an 8-year period were included. Factors with possible impact on diagnostic performance of EUS were analysed using logistic regression.

Results

Ninety patients met inclusion criteria and formed the study group. A total of 49 (54%) patients had an indwelling biliary stent at the time of EUS, of which 36 were plastic and 13 were self-expanding metal stents (SEMS). Twenty patients underwent venous resection and reconstruction (VRR). Staging was successfully performed in 100% unstented cases, 97% plastic stent and 54% SEMS, p<0.0001. In successfully staged patients, sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) for classification of resectability were 70%, 70%, 70%, 42% and 88%. For vascular involvement (VI), sensitivity, specificity, accuracy, PPV and NPV were 80%, 68%, 69%, 26% and 96%. Increasing tumour size OR 0.53 (95% CI, 0.30 to 0.95) was associated with a decrease in accuracy of VI classification.

Conclusions

EUS has modest diagnostic performance for stratification of staging. Staging was less likely to be completed when a SEMS was in situ. Staging EUS should ideally be performed before endoscopic retrograde cholangiopancreatography and biliary drainage.

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.

Upfront surgery vs. neoadjuvant therapy for resectable pancreatic cancer: a narrative review of available evidence

BACKGROUND AND OBJECTIVE

Though the use of neoadjuvant therapy (NAT) is increasing in the setting of borderline resectable (BRPC) and locally advance pancreatic cancer (LAPC), the role of NAT in resectable pancreatic cancer (RPC) remains uncertain.

METHODS

This is a narrative review, summarising the contemporary evidence and emerging studies comparing neoadjuvant therapy to upfront resection and adjuvant therapy in RPC.

KEY AND CONTENT AND FINDINGS

Upfront resection followed by adjuvant chemotherapy is currently the standard of care for RPC. Though BRPC and LAPC have reported significant overall survival benefits with NAT, those results have yet to be translated to RPC. Downstaging is only reported in a small proportion of patients who receive NAT; most have stable disease and a small number have progression. Preliminary trial data have largely been consistent with that observed in the past whereby a modest improvement in R0 resection rates and pathological findings is observed with NAT, however rates of distant recurrence and overall survival remain similar to upfront resection. A significant proportion further fail to achieve resection due to the side effects, deconditioning and delays to surgery. Most international recommendations have been guided by non-randomised data sets and long-term data from emerging phase III trials are yet to be published.

CONCLUSIONS

Although we have observed improved R0 resection rates with NAT, this has yet to translate to a robust improvement in overall survival. Concerns regarding delays to resection, and limited response to NAT remain a topic of ongoing investigation.

Impact of the extent of resection of neuroendocrine tumor liver metastases on survival: A systematic review and meta-analysis

In patients with neuroendocrine tumors with liver metastases (NETLMs), complete resection of both the primary and liver metastases is a potentially curative option. When complete resection is not possible, debulking of the tumour burden has been proposed to prolong survival. The objective of this systematic review was to evaluate the effect of curative surgery (R0-R1) and debulking surgery (R2) on overall survival (OS) in NETLMs. For the subgroup of R2 resections, outcomes were compared by the degree of hepatic debulking (≥ 90% or ≥ 70%). A systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines using PubMed, Medline, CINAHL, Cochrane, and Embase databases. Hazard ratios (HRs) were estimated for each study and pooled using a random-effects inverse-variance meta-analysis model. Of 538 articles retrieved, 11 studies (1,729 patients) reported comparisons between curative and debulking surgeries. After pooling these studies, OS was found to be significantly shorter in debulking resections, with an HR of 3.49 (95% confidence interval, 2.70–4.51; p < 0.001). Five studies (654 patients) compared outcomes between ≥ 90% and ≥ 70% hepatic debulking approaches. Whilst these studies reported a tendency for OS and progression-free survival to be shorter in those with a lower degree of debulking, they did not report sufficient data for this to be assessed in a formal meta-analysis. In patients with NETLM, OS following surgical resection is the best to achieve R0-R1 resection. There is also evidence for a progressive reduction in survival benefit with lesser debulking of tumour load.

P-P08 Towards effective analgesia in acute pancreatitis: a systematic review of randomised controlled trials

Background

The optimal analgesic strategy for patients with acute pancreatitis (AP) remains unknown. The present systematic review and meta-analysis aims to compare the efficacy of several analgesic modalities trialled in AP.

Methods

A systematic search of PubMed, MEDLINE and EMBASE was conducted up until June 2021, according to PRISMA Guidelines to identify all randomised control trials (RCTs) comparing analgesic modalities in AP.  The primary outcome measure was improvement in pain scores as reported on visual analogue scale (VAS) on day 0, day 1 and day 2.

Results

Twelve RCTs were identified including 542 patients. Seven trial drugs were compared: opiates, non-steroidal anti-inflammatories (NSAIDs), placebo, local anaesthetic, epidural, paracetamol and metamizole. A weighted single-arm effects estimate showed global improvement in VAS across all modalities from baseline to day 2. On visual inspection, epidural analgesia appears to provide the greatest improvement in pain scores within the first 24hrs, however at 48hrs it was comparable to opiates. Within the first 24hrs, NSAIDs offered similar pain-relief to opiates, while placebo also showed equivalence to other modalities but then plateaued. Local anaesthetics demonstrated least overall efficacy. VAS scores for opiate and non-opiate analgesics were comparable at baseline and day 1. The identified RCTs demonstrated significant heterogeneity in pain-relief reporting with relatively small datasets per study.

Conclusions

Given the incidence of AP there is remarkable paucity of level 1 evidence to guide pain management. Epidural administration is most effective analgesic modality within the first 24hrs of AP. NSAIDs are an effective opiate sparing alternative during the first 24hrs.

P-P31 Splanchnic vein thrombosis in acute pancreatitis: Incidence, risk factors and long term outcomes

Background

There is paucity of data on the incidence, risk factors and role of anticoagulation for splanchnic vein thrombosis (SVT) in acute pancreatitis (AP).

Methods

A retrospective review of AP admissions between 2018-2021 across North East England was undertaken. Data on demographics, etiology, severity of AP and SVT was collected. In addition, a selective anticoagulation policy for portal vein thrombosis (PVT) and progressive splenic vein thrombosis was explored.

Results

401 patients were included with a mean age of 57.0 and M:F ratio of 1.6:1. 152 patients developed intestinal oedematous pancreatitis and 249 developed necrotising pancreatitis based on Revised Atlanta criteria (RAC). 109 patients (27.2%) developed SVT of which 27 developed a PVT and splenic vein thrombus, 36 PVT only and 46 splenic vein thrombus only. 

On univariate analysis, alcoholic aetiology, severe pancreatitis, necrotising pancreatitis with &gt;50% necrosis and elevated CRP at 2 weeks were risk factors for developing SVT. On multivariable analysis, alcohol aetiology (OR 2.6, p = 0.002), and &gt;50% pancreatic necrosis (OR 14.6,p = 0.048) increased the risk of developing SVT .

58 patients received anticoagulation for SVT, with a median duration of 90 days of anticoagulation. Recanalization rates were higher for PVT when compared to splenic vein thrombosis. 6 patients developing bleeding complications whilst on anticoagulation therapy. 

Conclusions

A third of patients with AP develop SVT, particularly those with severe AP secondary to alcohol and with extensive pancreatic necrosis. A selective anticoagulation policy was associated with improved recanalization rates and fewer bleeding complications.

P-P23 Adjuvant chemotherapy in the treatment of intraductal papillary mucinous neoplasms of the pancreas: systematic review and meta-analysis

Background

The present systematic review aimed to compare survival outcomes of invasive intraductal papillary mucinous neoplasms (IIPMNs) treated with adjuvant chemotherapy versus surgery alone and to identify pathologic features that may predict survival benefit from adjuvant chemotherapy.

Methods

A systematic search of Medline, Pubmed, Scopus, and EMBASE was performed using the PRISMA framework. Studies comparing adjuvant chemotherapy and surgery alone for patients with IIPMNs were included. Primary endpoint was overall survival (OS). A narrative synthesis was performed to identify pathologic features that predicted survival benefits from adjuvant chemotherapy.  

Results

Eleven studies and 3393 patients with IIPMNs were included in the meta-analysis. Adjuvant chemotherapy significantly reduced risk of death in the overall cohort (HR 0.57, 95%-CI:0.38-0.87, p = 0.009) and node-positive patients (HR 0.29, 95%-CI:0.13-0.64, p = 0.002). Weighted median survival difference between adjuvant chemotherapy and surgery alone in node-positive patients was 11.6 months (95%-CI:3.83-19.38, p = 0.003) favouring chemotherapy. Adjuvant chemotherapy had no impact on OS in node-negative patients (HR 0.53, 95%-CI:0.20-1.43, p = 0.209). High heterogeneity (I2&gt;75%) was observed in pooled estimates of hazard ratios. Improved OS following adjuvant chemotherapy were reported for patients with stage III/IV disease, tumour size &gt;2 cm, node-positive status, grade 3 tumour differentiation, positive margin status, tubular carcinoma subtype, and presence of perineural or lymphovascular invasion.

Conclusions

Adjuvant chemotherapy was associated with improved OS in node-positive IIPMNs. However, the findings were limited by marked heterogeneity. Future large multicentre prospective studies are needed to confirm these findings and explore additional predictors of improved OS to guide patient selection for adjuvant chemotherapy.

P-P01 Impact of gastric resection and enteric anastomotic configuration on delayed gastric emptying after pancreaticoduodenectomy: a network meta-analysis

Background

Delayed gastric emptying (DGE) is frequent after pancreaticoduodenectomy (PD). Several randomised controlled trials (RCTs) have explored operative strategies to minimise DGE, however, the optimal combination of gastric resection approach, anastomotic route, and configuration, role of Braun enteroenterostomy remains unclear. 

Methods

MEDLINE, Embase, and CENTRAL databases were systematically searched for RCTs comparing gastric resection (Classic Whipple, pylorus-resecting, and pylorus-preserving), anastomotic route (antecolic vs retrocolic) and configuration (Billroth II vs Roux-en-Y), and enteroenterostomy (Braun vs no Braun). A random-effects, Bayesian network meta-analysis with non-informative priors was conducted to determine the optimal combination of approaches to PD for minimising DGE.

Results

Twenty-four RCTs, including 2526 patients and 14 approaches were included. There was some heterogeneity, although inconsistency was low. The overall incidence of DGE was 25.6% (n = 647). Pylorus-resecting, antecolic, Billroth II with Braun enteroenterostomy was associated with the lowest rates of DGE and ranked the best in 35% of comparisons. Classic Whipple, retrocolic, Billroth II with Braun ranked the worst for DGE in 32% of comparisons. Pairwise meta-analysis of retrocolic vs antecolic route of gastro-jejunostomy found increased risk of DGE with the retrocolic route (OR 2.1, 95% CrI; 0.92 - 4.7). Pairwise meta-analysis of Braun enteroenterostomy found a trend towards lower DGE rates with Braun compared to no Braun (OR 1.9, 95% CrI; 0.92 - 3.9). Having a Braun enteroenterostomy ranked the best in 96% of comparisons. 

Conclusions

Based on existing RCT evidence, a pylorus-resecting, antecolic, Billroth II with Braun enteroenterostomy may be associated with the lowest rates of DGE.

P-P03 Impact of routine nasogastric decompression versus no nasogastric decompression after pancreatoduodenectomy on perioperative outcomes: A meta-analysis of available evidence

Background

This meta-analysis reviewed the current evidence on the impact of routine Nasogastric decompression (NGD) versus no NGD after pancreatoduodenectomy on perioperative outcomes. 

Methods

PubMed, Medline, Scopus, Embase and Cochrane databases were searched for studies reporting the role of nasogastric tube decompression after pancreatoduodenectomy on perioperative outcomes were retrieved and analysed up to January 2021. 

Results

Eight studies with total of 1301 patients were enrolled of which 668 patients had routine NGD. Routine NGD was associated with a higher incidence of overall delayed gastric emptying (DGE) and clinically relevant DGE (OR = 2.51, 95% CI; 1.12 - 5.63, I2= 83%, P = 0.03, and OR = 3.64, 95% CI: 1.83 – 7.25, I2 = 54%, P &lt; 0.01, respectively). Routine NGD was also associated with a higher rate of Clavien-Dindo ≥ 2 complications (OR = 3.12, 95% CI: 1.05 – 9.28, I2 = 88%, P = 0.04), and increased length of hospital stay (MD = 2.67, 95% CI: 0.60 – 4.75, I2 = 97%, P = 0.02). There were no significant differences in overall complications (OR = 1.07, 95% CI: 0.79 – 1.46, I2 0%, P = 0.66), or postoperative pancreatic fistula (OR = 1.21, 95% CI: 0.86 – 1.72, I2 = 0%, P = 0.28) between the two groups.

Conclusions

Routine NGD may be associated with increased rates of DGE, major complications and longer length of stay after pancreatoduodenectomy. 

P-P15 Margin Accentuation Irreversible Electroporation in Stage III Pancreatic Cancer: A Systematic Review

Background

The present systematic review aimed to summarise the available evidence on indications and oncological outcomes after MA IRE for stage III pancreatic cancer (PC).

Methods

A literature search was performed in the Pubmed, MEDLINE, EMBASE, SCOPUS databases using the PRISMA framework to identify all MA IRE studies. 

Results

Nine studies with 235 locally advanced (LA) (82%, 192/235) or Borderline resectable (BR) PC (18%, 43/235) patients undergoing MA IRE pancreatic resection were included. Patients were mostly male (56%) with a weighted-mean age of 61 years (95% CI: 58–64). Pancreatoduodenectomy was performed in 51% (120/235) and distal pancreatectomy in 49% (115/235). R0 resection rate was 73% (77/105). Clavien Dindo grade 3–5 postoperative complications occurred in 19% (36/187). Follow-up intervals ranged from 3 to 29 months. Local and systematic recurrences were noted in 8 and 43 patients, respectively. The weighted-mean progression free survival was 11 months (95% CI: 7–15). The weighted-mean overall survival was 22 months (95% CI 20–23 months) and 8 months (95% CI 1–32 months) for MA IRE and IRE alone, respectively.

Conclusions

Early non-randomised data suggest MA IRE during pancreatic surgery for stage III pancreatic cancer may result in increased R0 resection rates and improved OS with acceptable postoperative morbidity. Further, larger studies are warranted to corroborate this evidence.

P-P41 Systematic review of Sarcopenia in Chronic Pancreatitis: prevalence, impact on surgical outcomes and survival

Background

Chronic pancreatitis(CP) is characterised by progressive inflammatory changes to the pancreas, leading to loss of endocrine and exocrine function. Emerging literature suggests sarcopenia may adversely affect outcomes for chronic pancreatitis patients. This systematic review examines the evidence surrounding the impact of sarcopenia on patients with CP.

Methods

A systematic literature search of PUBMED, MEDLINE and EMBASE databases identified articles describing body composition assessment in patients with CP. Data collected included definitions of sarcopenia, assessment methodology, baseline demographics, surgery related data and short- and long-term outcomes.

Results

9 studies, including 977 patients and a sarcopenia prevalence of 32.3% were included. Alcohol was the predominant aetiology. There was significant heterogeneity in definitions of sarcopenia used. CT was the main modality to assess for sarcopenia in 7 papers, MRI in 2 papers and clinical measurements in 2 papers. 2 papers included patients undergoing total pancreatectomy and Islet cell transplantation. None of the studies found a significant increase in complications with sarcopenia. 1 Year mortality in outpatients from one study of patients with CP was 16% in sarcopenic patients versus 3% (HR:6.69(95%CI:1.79–24.9),p&lt;0.001).

Conclusions

Sarcopenia is prevalent in patients with CP and has adverse impact on short- and long-term survival.

P-P02 Incidence and risk factors for chyle leak after pancreatic surgery: a systematic review and meta-analysis

Background

The incidence of, and risk factors for chyle leak, as defined by the 2017 International Study Group on Pancreatic Surgery (ISGPS), remain unknown. 

Methods

MEDLINE, EMBASE, and Scopus were systematically searched for studies of patients undergoing pancreatectomy that reported chyle leak according to the 2017 ISGPS definition. The primary outcomes were the incidence of overall and clinically-relevant chyle leak. A random-effects pairwise meta-analysis was used to identify risk factors where possible. 

Results

Thirty-five studies including 7083 patients were included in the meta-analysis. The weighted incidence of overall chyle leak was 6.8% (95% CI 5.6 - 8.2) and clinically-relevant chyle leak was 5.5% (95% CI 3.8 - 7.7). Pancreaticoduodenectomy, total pancreatectomy and distal pancreatectomy were associated with a CL incidence of 7.3%, 4.3%, 5.8% respectively. Fourteen individual risk factors for chyle leak were identified from included studies. Younger age, low prognostic nutritional index, para-aortic node manipulation, lymphatic involvement, and post-pancreatectomy pancreatitis were significantly associated with chyle leak, all from individual studies.

Conclusions

The incidence of overall chyle leak and clinically relevant chyle leak after pancreatic surgery, as defined by the 2017 ISGPS definition is 6.8% and 5.5% respectively. Several risk factors for chyle leak were identified in the present review, however, larger high-quality studies are needed to more accurately define these risks.

Impact of routine nasogastric decompression versus no nasogastric decompression after pancreaticoduodenectomy on perioperative outcomes: meta-analysis

Background

Consensus on the use of nasogastric decompression (NGD) after pancreaticoduodenectomy (PD) is lacking. This meta-analysis reviewed current evidence on the impact of routine NGD versus no NGD after PD on perioperative outcomes.

Methods

PubMed, Medline, Scopus, Embase and Cochrane databases were searched for studies reporting on the role of NGD after PD on perioperative outcomes. Data up to January 2021were retrieved and analysed.

Results

Eight studies were included, with a total of 1301 patients enrolled, of whom 668 had routine NGD. Routine NGD was associated with a higher incidence of overall delayed gastric emptying (DGE) (odds ratio (OR) 2.51, 95 per cent c.i. 1.12 to 5.63, I² = 83 per cent; P = 0.03) and clinically relevant DGE (OR 3.64, 95 per cent c.i. 1.83 to 7.25, I² = 54 per cent; P < 0.01), a higher rate of Clavien–Dindo grade II or higher complications (OR 3.12, 95 per cent c.i. 1.05 to 9.28, I² = 88 per cent; P = 0.04) and increased length of hospital stay (mean difference 2.67, 95 per cent c.i. 0.60 to 4.75, I² = 97 per cent; P = 0.02). There were no significant differences in overall complications (OR 1.07, 95 per cent c.i. 0.79 to 1.46, I² = 0 per cent; P = 0.66) or postoperative pancreatic fistula (OR 1.21, 95 per cent c.i. 0.86 to 1.72, I² = 0 per cent; P = 0.28) between patients with or those without routine NGD.

Conclusion

Routine NGD was associated with increased rates of DGE, major complications and longer length of stay after PD.

322 Clinical Factors Predictive of Both Successful and Unsuccessful Arterial Embolization in The Management of Lower Gastrointestinal Bleeding

Aim

To develop a model of clinical factors that may predict: (1) technically and clinically successful embolization of a bleeding vessel at Digital Subtraction Angiography (DSA) for lower gastrointestinal bleed (LGIB); (2) a negative DSA in the presence of positive CT-mesenteric angiography (CTMA) for LGIB.

Method

A retrospective cohort study of all DSAs conducted with intent for embolization for acute LGIB over a 10-year period was undertaken. Pre-procedural and intra-procedural clinical variables were evaluated using uni- and multi-variate analysis.

Results

123 DSAs were evaluated. Technical success was 81% (64/78) with clinical success 78%. Technical success was associated with super-selective approach, contrast extravasation on CT, haemoglobin drop, anatomical source and time from CT to DSA on univariate analysis. On multivariate analysis time from CT to DSA was significant with a higher success probability within 120 minutes with different factors being salient depending on degree of delay. Clinical success was only associated with APTT (&lt;27.5s). Technical failure from a negative DSA following a positive CTMA was associated with anatomical source, haemodynamic stability, platelet count and time from CT to DSA on univariate analysis. The latter three remained so on multivariate analysis.

Conclusions

A triaging approach to utilising emergency DSA may be helpful. If prolonged delay between a positive CT and DSA is anticipated, with haemodynamic stability and a near normal platelet count, the DSA may not be fruitful. Technical success may be more likely if DSA occurs within 120mins. Clinical success may be more likely if APTT is within normal range.

Systematic reviews of observational studies of Risk of Thrombosis and Bleeding in General and Gynecologic Surgery (ROTBIGGS): introduction and methodology

BACKGROUND

Venous thromboembolism (VTE) and bleeding are serious and potentially fatal complications of surgical procedures. Pharmacological thromboprophylaxis decreases the risk of VTE but increases the risk of major post-operative bleeding. The decision to use pharmacologic prophylaxis therefore represents a trade-off that critically depends on the incidence of VTE and bleeding in the absence of prophylaxis. These baseline risks vary widely between procedures, but their magnitude is uncertain. Systematic reviews addressing baseline risks are scarce, needed, and require innovations in methodology. Indeed, systematic summaries of these baseline risk estimates exist neither in general nor gynecologic surgery. We will fill this knowledge gap by performing a series of systematic reviews and meta-analyses of the procedure-specific and patient risk factor stratified risk estimates in general and gynecologic surgeries.

METHODS

We will perform comprehensive literature searches for observational studies in general and gynecologic surgery reporting symptomatic VTE or bleeding estimates. Pairs of methodologically trained reviewers will independently assess the studies for eligibility, evaluate the risk of bias by using an instrument developed for this review, and extract data. We will perform meta-analyses and modeling studies to adjust the reported risk estimates for the use of thromboprophylaxis and length of follow up. We will derive the estimates of risk from the median estimates of studies rated at the lowest risk of bias. The primary outcomes are the risk estimates of symptomatic VTE and major bleeding at 4 weeks post-operatively for each procedure stratified by patient risk factors. We will apply the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to rate evidence certainty.

DISCUSSION

This series of systematic reviews, modeling studies, and meta-analyses will inform clinicians and patients regarding the trade-off between VTE prevention and bleeding in general and gynecologic surgeries. Our work advances the standards in systematic reviews of surgical complications, including assessment of risk of bias, criteria for arriving at the best estimates of risk (including modeling of the timing of events and dealing with suboptimal data reporting), dealing with subgroups at higher and lower risk of bias, and use of the GRADE approach.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021234119.

Adjuvant Chemotherapy in the Treatment of Intraductal Papillary Mucinous Neoplasms of the Pancreas: Systematic Review and Meta-Analysis

Background

The present systematic review aimed to compare survival outcomes of invasive intraductal papillary mucinous neoplasms (IIPMNs) treated with adjuvant chemotherapy versus surgery alone and to identify pathologic features that may predict survival benefit from adjuvant chemotherapy.

Method

A systematic search of MEDLINE, PubMed, Scopus, and EMBASE was performed using the PRISMA framework. Studies comparing adjuvant chemotherapy and surgery alone for patients with IIPMNs were included. Primary endpoint was overall survival (OS). A narrative synthesis was performed to identify pathologic features that predicted survival benefits from adjuvant chemotherapy.

Results

Eleven studies and 3393 patients with IIPMNs were included in the meta-analysis. Adjuvant chemotherapy significantly reduced the risk of death in the overall cohort (HR 0.57, 95% CI 0.38–0.87, p = 0.009) and node-positive patients (HR 0.29, 95% CI 0.13–0.64, p = 0.002). Weighted median survival difference between adjuvant chemotherapy and surgery alone in node-positive patients was 11.6 months (95% CI 3.83–19.38, p = 0.003) favouring chemotherapy. Adjuvant chemotherapy had no impact on OS in node-negative patients (HR 0.53, 95% CI 0.20–1.43, p = 0.209). High heterogeneity (I² > 75%) was observed in pooled estimates of hazard ratios. Improved OS following adjuvant chemotherapy was reported for patients with stage III/IV disease, tumour size > 2 cm, node-positive status, grade 3 tumour differentiation, positive margin status, tubular carcinoma subtype, and presence of perineural or lymphovascular invasion.

Conclusion

Adjuvant chemotherapy was associated with improved OS in node-positive IIPMNs. However, the findings were limited by marked heterogeneity. Future large multicentre prospective studies are needed to confirm these findings and explore additional predictors of improved OS to guide patient selection for adjuvant chemotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00268-021-06309-8.

Systematic review of the incidence and risk factors for chyle leak after pancreatic surgery

BACKGROUND

The incidence of and risk factors for chyle leak, as defined by the 2017 International Study Group on Pancreatic Surgery, remain unknown.

METHODS

MEDLINE, EMBASE, and Scopus were systematically searched for studies of patients undergoing pancreatectomy that reported chyle leak according to the 2017 International Study Group on Pancreatic Surgery definition. The primary outcomes were the incidence of overall and clinically relevant chyle leak. A random-effects pairwise meta-analysis was used to calculate the incidence of chyle leak.

RESULTS

Thirty-five studies including 7,083 patients were included in the meta-analysis. The weighted incidence of overall chyle leak was 6.8% (95% confidence interval 5.6-8.2), and clinically relevant chyle leak was 5.5% (95% confidence interval 3.8-7.7). Pancreaticoduodenectomy, total pancreatectomy, and distal pancreatectomy were associated with a CL incidence of 7.3%, 4.3%, and 5.8%, respectively. Fourteen individual risk factors for chyle leak were identified from included studies. Younger age, low prognostic nutritional index, para-aortic node manipulation, lymphatic involvement, and post-pancreatectomy pancreatitis were significantly associated with chyle leak, all from individual studies.

CONCLUSION

The incidence of overall chyle leak and clinically relevant chyle leak after pancreatic surgery, as defined by the 2017 International Study Group on Pancreatic Surgery, is 6.8% and 5.5%, respectively. Several risk factors for chyle leak were identified in the present review; however, larger high-quality studies are needed to more accurately define these risks.

Systematic review and meta-analysis of risk factors of postoperative pancreatic fistula after distal pancreatectomy in the era of 2016 International Study Group pancreatic fistula definition

BACKGROUND

Risk factors for the development of clinically relevant POPF (CR-POPF) following distal pancreatectomy (DP) need clarification particularly following the 2016 International Study Group of Pancreatic Fistula (ISGPF) definition.

METHODS

A systemic search of MEDLINE, Pubmed, Scopus, and EMBASE were conducted using the PRISMA framework. Studies were evaluated for risk factors for the development CR-POPF after DP using the 2016 ISGPF definition. Further subgroup analysis was undertaken on studies ≥10 patients in exposed and non-exposed subgroups.

RESULTS

Forty-three studies with 8864 patients were included in the meta-analysis. The weighted rate of CR-POPF was 20.4% (95%-CI: 17.7-23.4%). Smoking (OR 1.29, 95%-CI: 1.08-1.53, p = 0.02) and open DP (OR 1.43, 95%-CI: 1.02-2.01, p = 0.04) were found to be significant risk factors of CR-POPF. Diabetes (OR 0.81, 95%-CI: 0.68-0.95, p = 0.02) was a significant protective factor against CR-POPF. Substantial heterogeneity was observed in the comparisons of pancreatic texture and body mass index. Seventeen risk factors achieved significance in a univariate or multivariate comparison as reported by individual studies in the narrative synthesis, however, they remain difficult to interpret as statistically significant comparisons were not uniform.

CONCLUSION

This meta-analysis found smoking and open DP to be risk factors and diabetes to be protective factor of CR-POPF in the era of 2016 ISGPF definition.

Impact of pancreatic enzyme replacement therapy on short- and long-term outcomes in advanced pancreatic cancer: meta-analysis of randomized controlled trials

Objectives: We analyzed randomized controlled trials (RCTs) to assess the impact of PERT on weight change, quality of life, and overall survival (OS) in patients with advanced pancreatic cancer (APC).Methods: All RCTs indexed in PubMed, Medline and Scopus, databases reporting PEI in APC and the effect of PERT were included up to August 2020. The primary outcome measure was OS and the secondary outcome measures were weight change and quality of life.Results: Four RCTs including 194 patients (107 males) were analyzed. Ninety-eight (50.5%) patients received PERT treatment. Treatment with PERT did not show a significant effect on OS (SMD 0.12, 95% confidence interval -0.46-0.70, p = 0.46). There was no difference in change in body weight (SMD 0.53, 95% confidence interval -0.72-1.77, p = 0.21). Quality of life was not significantly different in those taking PERT compared to controls.Conclusions: This meta-analysis found no significant difference in OS, change in weight or quality of life with use of PERT in APC. However, non-uniform designs and different end points , along with smaller number of patients, limit a more in-depth analysis of outcomes. Further, RCTs are warranted to support evidence of routine use of PERT in APC.