Minimally invasivE versus open total GAstrectomy (MEGA): study protocol for a multicentre randomised controlled trial (DRKS00025765)

INTRODUCTION

The only curative treatment for most gastric cancer is radical gastrectomy with D2 lymphadenectomy (LAD). Minimally invasive total gastrectomy (MIG) aims to reduce postoperative morbidity, but its use has not yet been widely established in Western countries. Minimally invasivE versus open total GAstrectomy is the first Western multicentre randomised controlled trial (RCT) to compare postoperative morbidity following MIG vs open total gastrectomy (OG).

METHODS AND ANALYSIS

This superiority multicentre RCT compares MIG (intervention) to OG (control) for oncological total gastrectomy with D2 or D2+LAD. Recruitment is expected to last for 2 years. Inclusion criteria comprise age between 18 and 84 years and planned total gastrectomy after initial diagnosis of gastric carcinoma. Exclusion criteria include Eastern Co-operative Oncology Group (ECOG) performance status >2, tumours requiring extended gastrectomy or less than total gastrectomy, previous abdominal surgery or extensive adhesions seriously complicating MIG, other active oncological disease, advanced stages (T4 or M1), emergency setting and pregnancy.The sample size was calculated at 80 participants per group. The primary endpoint is 30-day postoperative morbidity as measured by the Comprehensive Complications Index. Secondary endpoints include postoperative morbidity and mortality, adherence to a fast-track protocol and patient-reported quality of life (QoL) scores (QoR-15, EUROQOL EuroQol-5 Dimensions-5 Levels (EQ-5D), EORTC QLQ-C30, EORTC QLQ-STO22, activities of daily living and Body Image Scale). Oncological endpoints include rate of R0 resection, lymph node yield, disease-free survival and overall survival at 60-month follow-up.

ETHICS AND DISSEMINATION

Ethical approval has been received by the independent Ethics Committee of the Medical Faculty, University of Heidelberg (S-816/2021) and will be received from each responsible ethics committee for each individual participating centre prior to recruitment. Results will be published open access.

TRIAL REGISTRATION NUMBER

DRKS00025765.

Comparative effectiveness of medical treatment vs. metabolic surgery for histologically proven non-alcoholic steatohepatitis and fibrosis: a matched network meta-analysis

Background

Non-alcoholic steatohepatitis (NASH) comprises a major healthcare problem affecting up to 30% of patients with obesity and the associated risk for cardiovascular and liver-related mortality. Several new drugs for NASH-treatment are currently investigated. No study thus far directly compared surgical and non-surgical therapies for NASH. This network meta-analysis compares for the first time the effectiveness of different therapies for NASH using a novel statistical approach.

Methods

The study was conducted according to the PRISMA guidelines for network meta-analysis. PubMed, CENTRAL and Web of Science were searched without restriction of time or language using a validated search strategy. Studies investigating therapies for NASH in adults with liver biopsies at baseline and after at least 12 months were selected. Patients with liver cirrhosis were excluded. Risk of bias was assessed with ROB-2 and ROBINS-I-tools. A novel method for population-adjusted indirect comparison to include and compare single-arm trials was applied. Main outcomes were NASH-resolution and improvement of fibrosis.

Results

Out of 7,913 studies, twelve randomized non-surgical studies and twelve non-randomized surgical trials were included. NASH-resolution after non-surgical intervention was 29% [95% confidence interval (CI): 23-40%] and 79% (95% CI: 72-88%) after surgery. The network meta-analysis showed that surgery had a higher chance of NASH-resolution than medication [odds ratio (OR) =2.68; 95% CI: 1.44-4.97] while drug treatment was superior to placebo (OR =2.24; 95% CI: 1.55-3.24). Surgery (OR =2.18; 95% CI: 1.34-3.56) and medication (OR =1.79; 95% CI: 1.39-2.31) were equally effective to treat fibrosis compared to placebo without difference between them. The results did not change when only new drugs specifically developed for the treatment of NASH were included.

Conclusions

Metabolic surgery has a higher effectiveness for NASH-therapy than medical therapy while both were equally effective regarding improvement of fibrosis. Trials directly comparing surgery with medication must be urgently conducted. Patients with NASH should be informed about surgical treatment options.

Study protocol of REpeat versus SIngle ShoT Antibiotic prophylaxis in major Abdominal Surgery (RESISTAAS I): a prospective observational study of antibiotic prophylaxis practice for patients undergoing major abdominal surgery

INTRODUCTION

Surgical site infections (SSIs) are among the most common complications after abdominal surgery and develop in approximately 20% of patients. These patients suffer a 12% increase in mortality, underlying the need for strategies reducing SSI. Perioperative antibiotic prophylaxis is paramount for SSI prevention in major abdominal surgery. Yet, intraoperative redosing criteria are subjective and whether patients benefit from it remains unclear.

METHODS AND ANALYSIS

The REpeat versus SIngle ShoT Antibiotic prophylaxis in major Abdominal Surgery (RESISTAAS I) study is a single-centre, prospective, observational study investigating redosing of antibiotic prophylaxis in 300 patients undergoing major abdominal surgery. Adult patients scheduled for major abdominal surgery will be included. Current practice of redosing regarding number and time period will be recorded. Postoperative SSIs, nosocomial infections, clinically relevant infection-associated bacteria, postoperative antibiotic treatment, in addition to other clinical, pharmacological and economical outcomes will be evaluated. Differences between groups will be analysed with analysis of covariance.

ETHICS AND DISSEMINATION

RESISTAAS I will be conducted in accordance with the Declaration of Helsinki and internal, national and international standards of GCP. The Medical Ethics Review Board of Heidelberg University has approved the study prior to initiation (S-404/2021). The study has been registered on 7 February 2022 at German Clinical Trials Register, with identifier DRKS00027892. We plan to disseminate the results of the study in a peer-reviewed journal.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS): DRKS00027892.

Intraoperative visualisation of pancreatic leakage (ViP): study protocol for an IDEAL Stage I Post Market Clinical Study

INTRODUCTION

Pancreatic resections are an important field of surgery worldwide to treat a variety of benign and malignant diseases. Postoperative pancreatic fistula (POPF) remains a frequent and critical complication after partial pancreatectomy and affects up to 50% of patients. POPF increases mortality, prolongs the postoperative hospital stay and is associated with a significant economic burden. Despite various scientific approaches and clinical strategies, it has not yet been possible to develop an effective preventive tool. The SmartPAN indicator is the first surgery-ready medical device for direct visualisation of pancreatic leakage already during the operation. Applied to the surface of pancreatic tissue, it detects sites of biochemical leak via colour reaction, thereby guiding effective closure and potentially mitigating POPF development.

METHODS AND ANALYSIS

The ViP trial is a prospective single-arm, single-centre first in human study to collect data on usability and confirm safety of SmartPAN. A total of 35 patients with planned partial pancreatectomy will be included in the trial with a follow-up of 30 days after the index surgery. Usability endpoints such as adherence to protocol and evaluation by the operating surgeon as well as safety parameters including major intraoperative and postoperative complications, especially POPF development, will be analysed.

ETHICS AND DISSEMINATION

Following the IDEAL-D (Idea, Development, Exploration, Assessment, and Long term study of Device development and surgical innovation) framework of medical device development preclinical in vitro, porcine in vivo, and human ex vivo studies have proven feasibility, efficacy and safety of SmartPAN. After market approval, the ViP trial is the IDEAL Stage I trial to investigate SmartPAN in a clinical setting. The study has been approved by the local ethics committee as the device is used exclusively within its intended purpose. Results will be published in a peer-reviewed journal. The study will provide a basis for a future randomised controlled interventional trial to confirm clinical efficacy of SmartPAN.

TRIAL REGISTRATION NUMBER

German Clinical Trial Register DRKS00027559, registered on 4 March 2022.

Safety and efficacy of TRIANGLE operation applied in pancreatic surgery: a protocol of the systematic review and meta-analysis

BACKGROUND

Pancreatic surgery is regarded as the only curative treatment for pancreatic cancer (PC). As the neoadjuvant therapy is applied widely nowadays, the proportion of patients with PC undergoing surgery also with locally advanced tumour findings has increased accordingly. Especially in these situations, a radical resection of all tumour tissues is challenging. A novel surgical strategy has been introduced recently to achieve this aim, namely the TRIANGLE operation which comprises the radical resection of all nerve and lymphatic tissue between coeliac artery, superior mesenteric artery and mesenteric-portal axis without including extended lymphadenectomy outside this area. Due to currently published studies, Triangle Operation is a safe and feasible procedure. However, this has not been systematically analysed to date. This systematic review and meta-analysis aim to evaluate surgical and postoperative outcomes of Triangle Operation in pancreatic surgery.

METHODS AND ANALYSIS

Pubmed, Web of Science and Cochrane Central Register of Controlled Trials in the Cochrane Library will be searched from inception until 31 December 2022. This study will include all articles comparing Triangle Operation versus non-Triangle Operation in pancreatic surgery to assess outcomes. The primary endpoints will be R0 resection rate and 1-year overall survival. The secondary endpoints will be delayed gastric emptying, postoperative pancreatic fistula, post pancreatectomy haemorrhages and reoperation incidence, overall complications, mortality and 3-year overall survival. The study selection, study quality assessment, data extraction and critical appraisal will be carried out by two reviewers. Inter-reviewer disagreements will be evaluated by discussion with a third reviewer. Besides, a subgroup analysis will be conducted focused on robotic surgery, laparoscopic surgery and open surgery in detail. Additionally, the Grading of Recommendations, Assessment, Development and Evaluations framework will be performed to evaluate the strength of evidence.

ETHICS AND DISSEMINATION

This systematic review and meta-analysis will not require ethical approval. Results will be published in a peer-reviewed scientific journal.

PROSPERO REGISTRATION NUMBER

CRD42021234721.

Mid-term quality of life after gastric band removal and single-stage conversion to gastric bypass: a single-center cohort study

BACKGROUND

Revision surgeries in patients with failed gastric banding including band removal are increasingly necessary. However, long-term outcomes after band removal alone are unsatisfactory due to weight regain and limited improvement in quality of life. This study aimed to report mid-term quality of life outcomes after gastric band removal and single-stage conversion to Roux-en-Y gastric bypass.

METHODS

Data of 108 patients who underwent conversion surgery from 2011 to 2017 were extracted from a prospective database and retrospectively analyzed. During follow-up visits, physical and laboratory data as well as quality of life questionnaires were obtained.

RESULTS

Postoperative mean Moorehead score increased significantly after 1 year (1.62 ± 0.86, p < 0.001) and after 5 years (1.55 ± 0.84, p < 0.001) compared to baseline values (0.72 ± 1.1). The mean follow-up time was 53 months. Moorehead scores at 1, 2, and 5 years postoperative were available in 75% (n = 81), 71% (n = 77), and 42% (n = 45) of cases, respectively. Mixed ANOVA analysis showed a significantly superior increase in Moorehead score in males (p = 0.024). No other significant predictors were identified. Lasting BMI reduction (- 4.6 to 33.0 ± 6.7 kg/m², p < 0.001) and weight loss (- 12.9% (- 13.6 kg), p < 0.001) 5 years after conversion surgery were seen. Postoperative complications occurred in 35% (n = 38) of patients with a re-operation rate of 30.5% (n = 33).

CONCLUSION

The current study shows that band removal with single-stage gastric bypass in patients with failed gastric banding leads to a lasting improvement in quality of life and may be the rescue procedure of choice in this setting.

Mechanical stretching and chemical pyloroplasty to prevent delayed gastric emptying after esophageal cancer resection-a meta-analysis and review of the literature

BACKGROUND

Delayed gastric emptying (DGE) occurs in up to 40% of patients after esophageal resection and prolongs recovery and hospital stay. Surgically pyloroplasty does not effectively prevent DGE. Recently published methods include injection of botulinum toxin (botox) in the pylorus and mechanical interventions as preoperative endoscopic dilatation of the pylorus. The aim of this study was to investigate the efficacy of those methods with respect to the newly published Consensus definition of DGE.

METHODS

A systematic literature search using CENTRAL, Medline, and Web of Science was performed to identify studies that described pre- or intraoperative botox injection or mechanical stretching methods of the pylorus in patients undergoing esophageal resection. Frequency of DGE, anastomotic leakage rates, and length of hospital stay were analyzed. Outcome data were pooled as odd's ratio (OR) or mean difference using a random-effects model. Risk of bias was assessed using the Robins-I tool for non-randomized trials.

RESULTS

Out of 391 articles seven retrospective studies described patients that underwent preventive botulinum toxin injection and four studies described preventive mechanical stretching of the pylorus. DGE was not affected by injection of botox (OR 0.87, 95% confidence interval [CI] 0.37-2.03, P = 0.75), whereas mechanical stretching resulted in significant reduction of DGE (OR 0.26, 95% CI 0.14-0.5, P < 0.0001).

CONCLUSION

Mechanical stretching of the pylorus, but not injection of botox reduces DGE after esophageal cancer resection. A newly developed consensus definition should be used before the conduction of a large-scale randomized-controlled trial.

Long-term quality of life after gastric band removal and concomitant conversion to gastric bypass: A single center cohort study

Objective

To report long-term quality of life and determine predictors for improved quality of life after gastric band removal and concomitant conversion to Roux-en-Y gastric bypass.

Methods

Clinical data of all patients who underwent conversion surgery from 2011 to 2017 were extracted from a prospectively maintained bariatric database and retrospectively analysed. During scheduled follow-up visits at 1, 6, 12, 24, 36, 48, and 60 months after surgery, physical and laboratory data as well as quality of life questionnaires were obtained. The primary outcome was change in postoperative Moorehead-Ardelt Quality of Life Questionnaire II Score (Moorehead Score). Secondary outcomes included common efficacy and safety outcomes utilized in bariatric surgery. Mixed ANOVA analysis, Chi Square test and Fisher's exact test were used.

Results

Overall, 108 patients who underwent conversion surgery were included. Mean duration of banding until conversion was 11.3 ± 4.3 years. The reason for conversion surgery was band failure in 45.4% (n=49) and band intolerance in 33.3% (n=36) of patients. In the remaining 21.3% (n=23) of cases a combination of both failure and intolerance was present. Mean follow-up time was 53 months. Postoperative mean Moorehead Score increased significantly after one (1.6 ± 0.9, p&lt;0.01) and after five years (1.6 ± 0.8, p&lt;0.01) compared to baseline values (0.7 ± 1.1). Mixed ANOVA analysis showed a significantly superior increase in Moorehead Score in males (p=0.024). No other significant predictors were identified. Neither the reason for conversion, nor preoperative parameters or long-term postoperative outcome parameters including postoperative weight loss or safety outcomes significantly affected postoperative quality of life improvement. Lasting BMI reduction (-4.6 kg/m2, p&lt;0.01) to 33.0 ± 6.7 kg/m2 and weight loss (-12.9%, p&lt;0.01) five years after conversion surgery were present. Internal hernia was the most common early postoperative complication, occurring in 14.8% (n=16) of cases.

Conclusion

Band removal with concomitant gastric bypass in patients with failed gastric banding improves long-term quality of life and may be the rescue procedure of choice in this setting.

Does the change from conventional circular to linear stapling in proximal gastric bypass surgery affect long-term quality of life?

Objective

The continuous desire to improve bariatric surgery outcomes, and therefore patient satisfaction, leads to a constant search for new surgical approaches. Every change in a well-established protocol needs to undergo evaluation and its benefit for patients must be demonstrated. With respect to technical changes in bariatric surgery, long-term effects on quality of life have not yet been studied. We analyzed quality of life scores and clinical outcomes at a single bariatric center transitioning from circular to a linear bypass protocol.

Methods

Between June 2012 and March 2016, 235 patients were included in this retrospective study from a prospectively collected database. Two groups were compared. Group CBP included those patients treated with a circular stapling bypass protocol (n=117). This protocol was primarily used in 2012. Between 2013 and 2015 a transition period occurred. Thereafter, the linear stapling bypass protocol (Group LBP, n=118) was primarily utilized. Quality of life (QoL) was assessed with the Moorehead-Ardelt QoL score, which was gathered preoperatively, and at 1, 2, and 5 years after surgery.

Results

Quality of life scores improved significantly after intervention in both study groups. The most prominent improvement was seen within the first year after surgery. There were no statistically significant differences between the groups. During the first two years, quality of life score improvement occurred independently of achieved weight loss, whereas a correlation between QoL-improvement and reported weight loss was identified between 24 and 60 months postoperatively (r2 0.112, p&lt;0.001). Further, complications had no impact on change in QoL scores.

Conclusion

Quality of life scores assessed by the Moorehead-Ardelt QoL questionnaire were, independent of operative technique and postoperative weight loss, significantly improved in the first two years after gastric bypass surgery. Thereafter, QoL scores showed lasting improvement in correlation with further weight loss.

Systematic review on the use and management of drainages in pancreatic surgery

Objective

The use of drains in pancreatic surgery, both in distal pancreatectomy (DP) and partial pancreaticoduodenectomy (PD) is controversial. The aim of this meta-analysis was to assess the potential benefit of drainage use in pancreatic surgery on postoperative outcomes.

Methods

A systematic literature search was performed in MEDLINE, Web of Science and CENTRAL. All RCTs investigating the use and management of any drainage in patients undergoing pancreatectomy were included. Data on mortality, postoperative complications and length of hospital stay (LOS) were analysed. A random-effects model for Mantel-Haenzsel and inverse variance analysis was used. Cochrane RoB 2.0 tool and GRADE approach was used for assessment of risk of bias and certainty of evidence.

Results

Ten RCTs investigating drainage vs no drainage, timing of drainage removal or type of drainage in PD such as DP with a total of 2004 patients were included. Drainage vs no drainage: Three RCTs (two with PD and DP, one with PD only). Neither mortality (OR 1.57, 95%-CI: 0.62 to 3.93 p=0.34) nor overall complications (OR 0.88, 95%-CI: 0.71 to 1.08, p=0.21) differed between both groups (certainty of evidence: low). However, one trial was stopped prematurely because of higher 90-day mortality in the no drainage group. Early vs late drainage removal: Four RCTs (two with PD and DP, two with PD only). Early drain removal resulted in both a significant reduction of chyle leak (OR 0.22, 95%-CI: 0.06 to 0.59, p&lt;0.01) as well as a shortening of LOS (mean difference -2.64 days, 95%CI: -4.63 to -0.65, p&lt;0.01). For both outcomes the certainty of evidence was moderate. Mortality, postoperative pancreatic fistula and hemorrhage showed no difference between early vs late drainage removal (certainty of evidence: low). Active vs passive drainage: Three RCTs (one with PD and DP, two with PD only). None of the studies found any significant difference in outcome with regard to the type of drainage.

Conclusion

There is no evidence that drainages after pancreatic surgery should be standard of care. However, there is also no evidence that placing a drain leads to worse outcomes. If a drainage is used it should be removed early to avoid chyle leak and accelerate hospital discharge.

Meta-analysis of randomized controlled trials comparing minimal-invasive versus open pancreatic surgery

Objective

To compare perioperative outcomes of minimal-invasive pancreatic surgery (MIPS) to open pancreatic surgery (OPS) using data obtained from randomised controlled trials (RCTs).

Methods

Literature search was done in CENTRAL, Medline and Web of Science; all currently available RCTs comparing MIPS and OPS in adult patients requiring elective distal pancreatectomy (DP) or partial pancreatoduodenectomy (PD) were included in the analysis. Outcomes were mortality, general and pancreatic surgery specific morbidity and length of hospital stay (LOS). Subgroup analysis between PD and DP was performed. A random-effects model for Mantel-Haenzsel and inverse variance analysis was used. Cochrane RoB 2.0 tool and GRADE approach was used for assessment of risk of bias and certainty of evidence.

Results

A total of 166 patients for DP (80 MIPS vs. 86 OPS) in two RCTs and 856 for PD (429 MIPS vs. 427 OPS) in five RCTs were analysed. Meta-analysis showed a reduction of LOS by 1.2 days (-2 to -0.3, p&lt;0.01) and intraoperative blood loss by 143 ml (-186 to -101, p&lt;0.01) in MIPS. In the subgroup analysis reduction of LOS was only present for minimal-invasive DP (-2 days, -2.3 to -1.7, p&lt;0.01). A minimal-invasive approach showed reduction of surgical site infections (odds ratio 0.4, 0.1 to 0.96, p=0.04) and intraoperative blood loss (-141 ml, -181 to -101, p&lt;0.01) only in PD. Duration of surgery was about 96 min longer in minimal-invasive PD (56 to 137 min, p&lt;0.01), but not in DP. Analysis showed no significant difference between MIPS and OPS, as well as between subgroups, in mortality, complications according to Clavien-Dindo &gt;=3 and pancreatic surgery specific complications like postoperative pancreatic fistula and delayed gastric emptying. Certainty of evidence according to the GRADE approach was moderate to low.

Conclusion

This meta-analysis of level 1 evidence shows reduced LOS and intraoperative blood loss in MIPS compared to OPS. Morbidity and mortality did not differ between MIPS and OPS. Longer duration of surgery in minimal-invasive PD hints that minimal-invasive technique in PD is more challenging than in DP. However, patients undergoing minimal-invasive PD seem to benefit from lower surgical site infections and less intraoperative blood loss.

Finding the best available evidence in pancreatic surgery – the EVIglance randomised controlled trial

Objective

Profound and thorough literature search is a vital element of evidence-based medicine. However, increasing number of publications and limited time make it hard to find the best available evidence. The objective of this randomised controlled trial (RCT) was to demonstrate the superiority of the ISGPS Evidence Map of Pancreatic Surgery (via EVIglance on www.evidencemap.surgery) compared to a conventional literature search via PubMed for answering clinically relevant questions in pancreatic surgery.

Methods

A single-centre, blinded, cross-over RCT including medical students, residents and consultants as participants was performed. Participants conducted literature searches with two predefined PICO (Patient, Intervention, Control, Outcome) questions, one with PubMed and the other with EVIglance. The order of the search tools and the PICO questions were assigned by randomisation. Primary endpoint was time in minutes until a synopsis was made regarding the PICO question. The synopsis was characterised by the direction of the effect and the certainty of evidence. Three times 28 participants were needed to show a minimal difference of 3 minutes at a level of significance of alpha = 1.67%. Furthermore, the correct number of RCTs found by participants that were relevant to answer the PICO question was analysed.

Results

Each 28 medical students, residents and consultants were randomised and analysed. A synopsis for the PICO question was found with PubMed after 10.8 minutes and with EVIglance after 1.7 minutes (95%-CI for difference: 9.9 to 8.3 minutes; p&lt;0.001). EVIglance answered the PICO significantly faster in all groups (medical students, residents and consultants) even after Bonferroni correction. Participants were able to guess both the direction of the effect (95% vs 48%; p&lt;0.001) and the certainty of evidence (99% vs 30%; p&lt;0.001) better with EVIglance than with PubMed. The correct number of relevant RCTs to answer the PICO question was found more often with EVIglance compared to PubMed (99% vs 15%; p&lt;0.001).

Conclusion

Pancreatic surgeons find best available evidence faster via EVIglance on www.evidencemap.surgery. Furthermore, a synopsis made from EVIglance is more concise regarding direction of effect and certainty of evidence. Given the advantages of EVIglance it may be considered the new gold standard for finding best available evidence in pancreatic surgery.

Therapeutic lymphography for persistent chyle leak after pancreatic surgery

BACKGROUND

Chyle leak is a common complication following pancreatic surgery. After failure of conservative treatment, lymphography is one of the last therapeutic options. The objective of this study was to evaluate whether lymphography represents an effective treatment for severe chyle leak (International study Group on Pancreatic Surgery, grade C) after pancreatic surgery.

METHODS

Patients with grade C chyle leak after pancreatic surgery who received transpedal or transnodal therapeutic lymphography between 2010 and 2020 were identified from a prospectively maintained database. Clinical success of the lymphography was evaluated according to percent decrease of drainage output after lymphography (>50% decrease = partial success; >85% decrease = complete success).

RESULTS

Of the 48 patients undergoing lymphography, 23 had a clinically successful lymphography: 14 (29%) showed partial and 9 (19%) complete success. In 25 cases (52%) lymphography did not lead to a significant reduction of chyle leak. Successful lymphography was associated with earlier drain removal and hospital discharge [complete clinical success: 7.1 days (±4.1); partial clinical success: 12 days (±9.1), clinical failure: 19 days (±19) after lymphography; p = 0.006]. No serious adverse events were observed.

CONCLUSION

Therapeutic lymphography is a feasible, safe, and effective option for treating grade C chyle leak after pancreatic surgery.

Protocol of a prospective study investigating the association of PAncreatic parenchymal RISk factors with postoperative pancreatic fistula after partial pancreaticoduodenectomy (PARIS trial)

INTRODUCTION

Partial pancreatoduodenectomy (PD) is the treatment of choice for many malignant and benign diseases of the pancreatic head. Postoperative complication rates of up to 40% are regularly reported. One of the most common and potentially life-threatening complication is the postoperative pancreatic fistula (POPF). Parenchymal risk factors like main pancreatic duct diameter or texture of the pancreatic gland have already been identified in retrospective studies. The aim of this study is to evaluate the diagnostic value of parenchymal risk factors on POPF in a prospective manner.

METHODS AND ANALYSIS

All patients scheduled for elective PD at the Department of General, Visceral and Transplantation Surgery of the University of Heidelberg will be screened for eligibility. As diagnostic factors, diameter and texture of the pancreatic gland as well as radiological and histopathological features will be recorded. Furthermore, the new four class risk classification system by the International Study Group of Pancreatic Surgery (ISGPS) will be recorded. The postoperative course will be monitored prospectively. The primary endpoint will be the association of the main pancreatic duct size and the texture of the pancreatic gland on POPF according to the updated ISGPS definition. The diagnostic value of the above-mentioned factors for POPF will be evaluated in a univariable and multivariable analysis.

ETHICS AND DISSEMINATION

PARIS is a monocentric, prospective, diagnostic study to evaluate the association of parenchymal risk factors and the development of POPF approved by the Ethics Committee of the medical faculty of Heidelberg University (S-344/2019). Results will be available in 2022 and will be published at national and international meetings. With this knowledge, the intraoperative and perioperative decision-making process could be eased and improve the individual outcome of patient.

TRIAL REGISTRATION NUMBER

DRKS00017184.

Postpancreatectomy Acute Pancreatitis (PPAP): Definition and Grading From the International Study Group for Pancreatic Surgery (ISGPS)

OBJECTIVE

The ISGPS aimed to develop a universally accepted definition for PPAP for standardized reporting and outcome comparison.

BACKGROUND

PPAP is an increasingly recognized complication after partial pancreatic resections, but its incidence and clinical impact, and even its existence are variable because an internationally accepted consensus definition and grading system are lacking.

METHODS

The ISGPS developed a consensus definition and grading of PPAP with its members after an evidence review and after a series of discussions and multiple revisions from April 2020 to May 2021.

RESULTS

We defined PPAP as an acute inflammatory condition of the pancreatic remnant beginning within the first 3 postoperative days after a partial pancreatic resection. The diagnosis requires (1) a sustained postoperative serum hyperamylasemia (POH) greater than the institutional upper limit of normal for at least the first 48 hours postoperatively, (2) associated with clinically relevant features, and (3) radiologic alterations consistent with PPAP. Three different PPAP grades were defined based on the clinical impact: (1) grade postoperative hyperamylasemia, biochemical changes only; (2) grade B, mild or moderate complications; and (3) grade C, severe life-threatening complications.

DISCUSSIONS

The present definition and grading scale of PPAP, based on biochemical, radiologic, and clinical criteria, are instrumental for a better understanding of PPAP and the spectrum of postoperative complications related to this emerging entity. The current terminology will serve as a reference point for standard assessment and lend itself to developing specific treatments and prevention strategies.

Clinical outcomes of patients treated on the Heidelberg interprofessional training ward vs. care on a conventional surgical ward: A retrospective cohort study

Interprofessional training wards (IPTW) are a form of interprofessional education enabling trainees of different healthcare professions to work together in teams. Concerns about patient safety are a major barrier to the implementation of IPTWs. The objective of this retrospective study was to analyze patient relevant clinical outcomes on Germany's first IPTW (Heidelberger Interprofessionelle Ausbildungsstation; HIPSTA) in the Department of Surgery at University Hospital Heidelberg in comparison to a conventional surgical ward (CSW). The setting is a large tertiary care center with a focus on major oncological surgery. The endpoints were postoperative complications according to the Dindo-Clavien Classification and a set of patient-safety outcomes. In total, 232 patients treated on HIPSTA were retrospectively compared with 465 patients on a CSW. Baseline characteristics were comparable between groups. No significant difference between rate or severity of overall postoperative complications was observed. In-hospital mortality did not significantly differ between groups. However, the mean length of hospital stay was significantly shorter on HIPSTA. Furthermore, HIPSTA patients had less frequent reoperations. Patient safety in surgical IPTW was not compromised in comparison to a CSW, and there were some areas where significantly better outcomes were identified.

Prognostic relevance of the revised R status definition in pancreatic cancer: meta-analysis

BACKGROUND

The prognostic impact of margin status is reported with conflicting results after pancreatic cancer resection. While some studies validated an uninvolved resection margin (R0) 1 mm or more of tumour clearance, others have failed to show benefit. This systematic review and meta-analysis aimed to investigate the effects of margin definitions on median overall survival (OS).

METHODS

MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for studies reporting associations between resection margins and OS between 2010 and 2021. Data regarding margin status (R0 circumferential resection margin (CRM) negative (CRM-), R0 CRM positive (CRM+), R0 direct, and R1 and OS were extracted. Hazard ratios (HRs) were pooled with a random-effects model. The risk of bias was evaluated with the Quality in Prognosis Studies (QUIPS) tool.

RESULTS

The full texts of 774 studies were screened. In total, 21 studies compromising 6056 patients were included in the final synthesis. In total, 188 (24 per cent) studies were excluded due to missing margin definitions. The R0 (CRM+) rate was 50 per cent (95 per cent confidence interval (c.i.) 0.40 to 0.61) and the R0 (CRM-) rate was 38 per cent (95 per cent c.i. 0.29 to 0.47). R0 (CRM-) resection was independently associated with improved OS compared to combined R1 and R0 (CRM+; HR 1.36, 95 per cent c.i. 1.23 to 1.56).

CONCLUSION

The revised R status was confirmed as an independent prognosticator compared to combined R0 (CRM+) and R1. The limited number of studies, non-standardized pathology protocols, and the varying number of margins assessed hamper comparability.

Learning Curves in Open, Laparoscopic, and Robotic Pancreatic Surgery: A Systematic Review and Proposal of a Standardization

Objective

To depict and analyze learning curves for open, laparoscopic, and robotic pancreatoduodenectomy (PD) and distal pancreatectomy (DP).

Background

Formal training is recommended for safe introduction of pancreatic surgery but definitions of learning curves vary and have not been standardized.

Methods

A systematic search on PubMed, Web of Science, and CENTRAL databases identified studies on learning curves in pancreatic surgery. Primary outcome was the number needed to reach the learning curve as defined by the included studies. Secondary outcomes included endpoints defining learning curves, methods of analysis (statistical/arbitrary), and classification of learning phases.

Results

Out of 1115 articles, 66 studies with 14,206 patients were included. Thirty-five studies (53%) based the learning curve analysis on statistical calculations. Most often used parameters to define learning curves were operative time (n = 51), blood loss (n = 17), and complications (n = 10). The number of procedures to surpass a first phase of learning curve was 30 (20-50) for open PD, 39 (11-60) for laparoscopic PD, 25 (8-100) for robotic PD (P = 0.521), 16 (3-17) for laparoscopic DP, and 15 (5-37) for robotic DP (P = 0.914). In a three-phase model, intraoperative parameters improved earlier (first to second phase: operating time -15%, blood loss -29%) whereas postoperative parameters improved later (second to third phase: complications -46%, postoperative pancreatic fistula -48%). Studies with higher sample sizes showed higher numbers of procedures needed to overcome the learning curve (rho = 0.64, P < 0.001).

Conclusions

This study summarizes learning curves for open-, laparoscopic-, and robotic pancreatic surgery with different definitions, analysis methods, and confounding factors. A standardized reporting of learning curves and definition of phases (competency, proficiency, mastery) is desirable and proposed.

The TRIANGLE operation for pancreatic head and body cancers: early postoperative outcomes

BACKGROUND

Surgical resection is the mainstay of potential cure for patients with pancreatic cancer, however, local recurrence is frequent. Previously, we have described an extended resection technique for pancreatoduodenectomy aiming at a radical resection of the nerve and lymphatic tissue between celiac artery, superior mesenteric artery and mesenteric-portal axis (TRIANGLE operation). Until now, data on postoperative outcome have not been reported, yet.

METHODS

Patients who underwent either partial (PD) or total pancreatoduodenectomy (TP) applying the TRIANGLE procedure were identified. These cohorts were compared to matched historic cohorts with standard resections.

RESULTS

Overall, 330 patients were analysed (PD_TRIANGLE and PD_STANDARD, each n = 108; TP_TRIANGLE and TP_STANDARD, each n = 57). More lymph nodes were harvested in TRIANGLE compared to standard resection (PD: 27.5 (21-35) versus 31.5 (24-40); P = 0.0187, TP: 33 (28-49) versus 44 (29-53); P = 0.3174) and the rate of tumour positive resections margins, R1(direct), dropped. Duration of operation was significantly longer and blood loss higher. Postoperative mortality and complications did not differ significantly.

CONCLUSION

Pancreatoduodenectomy according to the TRIANGLE protocol can be performed without increased morbidity and mortality at a high-volume centre. Long-term survival and quality of life need to be investigated in prospective clinical trials with adequate sample size.

Systematic Review of Prognostic Role of Blood Cell Ratios in Patients with Gastric Cancer Undergoing Surgery

Various blood cell ratios exist which seem to have an impact on prognosis for resected gastric cancer patients. The aim of this systematic review was to investigate the prognostic role of blood cell ratios in patients with gastric cancer undergoing surgery in a curative attempt. A systematic literature search in MEDLINE (via PubMed), CENTRAL, and Web of Science was performed. Information on survival and cut-off values from all studies investigating any blood cell ratio in resected gastric cancer patients were extracted. Prognostic significance and optimal cut-off values were calculated by meta-analyses and a summary of the receiver operating characteristic. From 2831 articles, 65 studies investigated six different blood cell ratios (prognostic nutritional index (PNI), lymphocyte to monocyte ratio (LMR), systemic immune-inflammation index (SII), monocyte to lymphocyte ratio (MLR), neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR)). There was a significant association for the PNI and NLR with overall survival and disease-free survival and for LMR and NLR with 5-year survival. The used cut-off values had high heterogeneity. The available literature is flawed by the use of different cut-off values hampering evidence-based patient treatment and counselling. This article provides optimal cut-off values recommendations for future research.

Is metabolic syndrome a risk factor in hepatectomy? A meta-analysis with subgroup analysis for histologically confirmed hepatic manifestations

BACKGROUND

Metabolic syndrome (MetS) is a risk factor in surgery. MetS can progress to metabolic (dysfunction)-associated fatty liver disease (MAFLD), a vast-growing etiology of primary liver tumors which are major indications for liver surgery. The aim of this meta-analysis was to investigate the impact of MetS on complications and long-term outcomes after hepatectomy.

METHODS

The protocol for this meta-analysis was registered at PROSPERO prior to data extraction. MEDLINE, Web of Science, and Cochrane Library were searched for publications on liver resections and MetS. Comparative studies were included. Outcomes encompassed postoperative complications, mortality, and long-term oncologic status. Data were pooled as odds ratio (OR) with a random-effects model. Risk of bias was assessed using the Quality in Prognostic Studies tool (QUIPS), and the certainty of the evidence was evaluated with GRADE. Subgroup analyses for patients with histopathologically confirmed non-alcoholic fatty liver disease (NAFLD) versus controls were performed.

RESULTS

The meta-analyses included fifteen comparative studies. Patients with MetS suffered significantly more overall complications (OR 1.55; 95% CI [1.05; 2.29]; p=0.03), major complications (OR 1.97 95% CI [1.13; 3.43]; p=0.02; I²=62%), postoperative hemorrhages (OR 1.76; 95% CI [1.23; 2.50]; p=0.01) and infections (OR 1.63; 95% CI [1.03; 2.57]; p=0.04). There were no significant differences in mortality, recurrence, 1- or 5-year overall or recurrence-free survivals. Patients with histologically confirmed NAFLD did not have significantly more overall complications; however, PHLF rates were increased (OR 4.87; 95% CI [1.22; 19.47]; p=0.04). Recurrence and survival outcomes did not differ significantly. The certainty of the evidence for each outcome ranged from low to very low.

CONCLUSION

Patients with MetS that undergo liver surgery suffer more complications, such as postoperative hemorrhage and infection but not liver-specific complications-PHLF and biliary leakage. Histologically confirmed NAFLD is associated with significantly higher PHLF rates, yet, survivals of these patients are similar to patients without the MetS. Further studies should focus on identifying the tipping point for increased risk in patients with MetS-associated liver disease, as well as reliable markers of MAFLD stages and early markers of PHLF.

TRIAL REGISTRATION

PROSPERO Nr: CRD42021253768.

Statin use is associated with the reduction in hepatocellular carcinoma recurrence after liver surgery

Background

Hepatocellular carcinoma (HCC) is the sixth most common form of cancer worldwide. Although surgical treatments have an acceptable cure rate, tumor recurrence is still a challenging issue. In this meta-analysis, we investigated whether statins prevent HCC recurrence following liver surgery.

Methods

PubMed, Web of Science, EMBASE and Cochrane Central were searched. The Outcome of interest was the HCC recurrence after hepatic surgery. Pooled estimates were represented as hazard ratios (HRs) and odds ratios (ORs) using a random-effects model. Summary effect measures are presented together with their corresponding 95% confidence intervals (CI). The certainty of evidence was evaluated using the Grades of Research, Assessment, Development and Evaluation (GRADE) approach.

Results

The literature search retrieved 1362 studies excluding duplicates. Nine retrospective studies including 44,219 patients (2243 in the statin group and 41,976 in the non-statin group) were included in the qualitative analysis. Patients who received statins had a lower rate of recurrence after liver surgery (HR: 0.53; 95% CI: 0.44–0.63; p < 0.001). Moreover, Statins decreased the recurrence 1 year after surgery (OR: 0.27; 95% CI: 0.16–0.47; P < 0.001), 3 years after surgery (OR: 0.22; 95% CI: 0.15–0.33; P < 0.001), and 5 years after surgery (OR: 0.28; 95% CI: 0.19–0.42; P < 0.001). The certainty of evidence for the outcomes was moderate.

Conclusion

Statins increase the disease-free survival of patients with HCC after liver surgery. These drugs seem to have chemoprevention effects that decrease the probability of HCC recurrence after liver transplantation or liver resection.

Antecolic versus retrocolic reconstruction after partial pancreaticoduodenectomy

BACKGROUND

Pancreatic cancer remains one of the five leading causes of cancer deaths in industrialised nations. For adenocarcinomas in the head of the gland and premalignant lesions, partial pancreaticoduodenectomy represents the standard treatment for resectable tumours. The gastro- or duodenojejunostomy after partial pancreaticoduodenectomy can be reestablished via either an antecolic or retrocolic route. The debate about the more favourable technique for bowel reconstruction is ongoing.

OBJECTIVES

To compare the effectiveness and safety of antecolic and retrocolic gastro- or duodenojejunostomy after partial pancreaticoduodenectomy.

SEARCH METHODS

In this updated version, we conducted a systematic literature search up to 6 July 2021 to identify all randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Library 2021, Issue 6, MEDLINE (1946 to 6 July 2021), and Embase (1974 to 6 July 2021). We applied no language restrictions. We handsearched reference lists of identified trials to identify further relevant trials, and searched the trial registries clinicaltrials.govand World Health Organization International Clinical Trials Registry Platform for ongoing trials.

SELECTION CRITERIA

We considered all RCTs comparing antecolic with retrocolic reconstruction of bowel continuity after partial pancreaticoduodenectomy for any given indication to be eligible.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the identified references and extracted data from the included trials. The same two review authors independently assessed risk of bias of included trials, according to standard Cochrane methodology. We used a random-effects model to pool the results of the individual trials in a meta-analysis. We used odds ratios (OR) to compare binary outcomes and mean differences (MD) for continuous outcomes.

MAIN RESULTS

Of a total of 287 citations identified by the systematic literature search, we included eight randomised controlled trials (reported in 11 publications), with a total of 818 participants. There was high risk of bias in all of the trials in regard to blinding of participants and/or outcome assessors and unclear risk for selective reporting in six of the trials. There was little or no difference in the frequency of delayed gastric emptying (OR 0.67; 95% confidence interval (CI) 0.41 to 1.09; eight trials, 818 participants, low-certainty evidence) with relevant heterogeneity between trials (I2=40%). There was little or no difference in postoperative mortality (risk difference (RD) -0.00; 95% CI -0.02 to 0.01; eight trials, 818 participants, high-certainty evidence); postoperative pancreatic fistula (OR 1.01; 95% CI 0.73 to 1.40; eight trials, 818 participants, low-certainty evidence); postoperative haemorrhage (OR 0.87; 95% CI 0.47 to 1.59; six trials, 742 participants, low-certainty evidence); intra-abdominal abscess (OR 1.11; 95% CI 0.71 to 1.74; seven trials, 788 participants, low-certainty evidence); bile leakage (OR 0.82; 95% CI 0.35 to 1.91; seven trials, 606 participants, low-certainty evidence); reoperation rate (OR 0.68; 95% CI 0.34 to 1.36; five trials, 682 participants, low-certainty evidence); and length of hospital stay (MD -0.21; 95% CI -1.41 to 0.99; eight trials, 818 participants, low-certainty evidence). Only one trial reported quality of life, on a subgroup of 73 participants, also without a relevant difference between the two groups at any time point. The overall certainty of the evidence was low to moderate, due to some degree of heterogeneity, inconsistency and risk of bias in the included trials.

AUTHORS' CONCLUSIONS

There was low- to moderate-certainty evidence suggesting that antecolic reconstruction after partial pancreaticoduodenectomy results in little to no difference in morbidity, mortality, length of hospital stay, or quality of life. Due to heterogeneity in definitions of the endpoints between trials, and differences in postoperative management, future research should be based on clearly defined endpoints and standardised perioperative management, to potentially elucidate differences between these two procedures. Novel strategies should be evaluated for prophylaxis and treatment of common complications, such as delayed gastric emptying.

Prognostic role of selection criteria for liver transplantation in patients with hepatocellular carcinoma: a network meta-analysis

BACKGROUND

Patients with hepatocellular carcinoma (HCC) are selected for transplantation if they have a low tumour burden and low risk of recurrence. The morphometric Milan criteria have been the cornerstone for patient selection, but dynamic morphological and biological tumour characteristics surfaced as an encouraging tool to refine the selection of patients with HCC and to support the expansion of the Milan criteria. The outcomes of the most prevalent models that select patients with HCC for liver transplantation were analysed in this study, which aimed to identify the selection model that offered the best recurrence-free and overall survival after transplantation.

METHODS

Studies that compared Milan, University of California San Francisco (UCSF), up-to-seven (UPTS), alpha-fetoprotein (AFP), and MetroTicket 2.0 (MT2) models were included. One-year, 3-year, and 5-year recurrence-free and overall survival rates of patients selected for transplantation using different models were analysed.

RESULTS

A total of 60 850 adult patients with HCC selected for liver transplantation using Milan, UCSF, UPTS, AFP, or MT2 criteria were included. Patients selected for transplantation using the MT2 model had the highest 1-, 3-, and 5-year recurrence-free survival. In addition, patients selected for transplantation using MT2 criteria had the best 1- and 3-year overall survival, whereas patients selected for transplantation using the Milan criteria had the best 5-year overall survival rates.

CONCLUSION

The MT2 model offered the best post-transplant outcomes in patients with HCC, highlighting the importance of considering tumour morphology and biology when selecting patients with HCC for liver transplantation.