Laparoscopic cholecystectomy critical view of safety (LC-CVS): a multi-national validation study of an objective, procedure-specific assessment using video-based assessment (VBA).

BACKGROUND: A novel 6-item objective, procedure-specific assessment for laparoscopic cholecystectomy incorporating the critical view of safety (LC-CVS OPSA) was developed to support trainee formative and summative assessments. The LC-CVS OPSA included two retraction items (fundus and infundibulum retraction) and four CVS items (hepatocystic triangle visualization, gallbladder-liver separation, cystic artery identification, and cystic duct identification). The scoring rubric for retraction consisted of poor (frequently outside of defined range), adequate (minimally outside of defined range) and excellent (consistently inside defined range) and for CVS items were "poor-unsafe", "adequate-safe", or "excellent-safe". METHODS: A multi-national consortium of 12 expert LC surgeons applied the OPSA-LC CVS to 35 unique LC videos and one duplicate video. Primary outcome measure was inter-rater reliability as measured by Gwet's AC2, a weighted measure that adjusts for scales with high probability of random agreement. Analysis of the inter-rater reliability was conducted on a collapsed dichotomous scoring rubric of "poor-unsafe" vs. "adequate/excellent-safe". RESULTS: Inter-rater reliability was high for all six items ranging from 0.76 (hepatocystic triangle visualization) to 0.86 (cystic duct identification). Intra-rater reliability for the single duplicate video was substantially higher across the six items ranging from 0.91 to 1.00. CONCLUSIONS: The novel 6-item OPSA LC CVS demonstrated high inter-rater reliability when tested with a multi-national consortium of LC expert surgeons. This brief instrument focused on safe surgical practice was designed to support the implementation of entrustable professional activities into busy surgical training programs. Instrument use coupled with video-based assessments creates novel datasets with the potential for artificial intelligence development including computer vision to drive assessment automation.

A multi-national, video-based qualitative study to refine training guidelines for assigning an "unsafe" score in laparoscopic cholecystectomy critical view of safety.

BACKGROUND: The critical view of safety (CVS) was incorporated into a novel 6-item objective procedure-specific assessment for laparoscopic cholecystectomy (LC-CVS OPSA) to enhance focus on safe completion of surgical tasks and advance the American Board of Surgery's entrustable professional activities (EPAs) initiative. To enhance instrument development, a feasibility study was performed to elucidate expert surgeon perspectives regarding "safe" vs. "unsafe" practice. METHODS: A multi-national consortium of 11 expert LC surgeons were asked to apply the LC-CVS OPSA to ten LC videos of varying surgical difficulty using a "safe" vs. "unsafe" scale. Raters were asked to provide written rationale for all "unsafe" ratings and invited to provide additional feedback regarding instrument clarity. A qualitative analysis was performed on written responses to extract major themes. RESULTS: Of the 660 ratings, 238 were scored as "unsafe" with substantial variation in distribution across tasks and raters. Analysis of the comments revealed three major categories of "unsafe" ratings: (a) inability to achieve the critical view of safety (intended outcome), (b) safe task completion but less than optimal surgical technique, and (c) safe task completion but risk for potential future complication. Analysis of reviewer comments also identified the potential for safe surgical practice even when CVS was not achieved, either due to unusual anatomy or severe pathology preventing safe visualization. Based upon findings, modifications to the instructions to raters for the LC-CVS OPSA were incorporated to enhance instrument reliability. CONCLUSIONS: A safety-based LC-CVS OPSA has the potential to significantly improve surgical training by incorporating CVS formally into learner assessment. This study documents the perspectives of expert biliary tract surgeons regarding clear identification and documentation of unsafe surgical practice for LC-CVS and enables the development of training materials to improve instrument reliability. Learnings from the study have been incorporated into rater instructions to enhance instrument reliability.

Regulatory T Cell Inhibition by P60 Combined with Adenoviral AFP Transduced Dendritic Cells for Immunotherapy of Hepatocellular Carcinoma.

BACKGROUND & AIMS: Vaccination with tumor-associated antigen-pulsed dendritic cells leads to specific T-cell response against hepatocellular carcinoma. However, clinical response has been shown to be limited. High regulatory T-cell count is associated with poor prognosis and seems to mediate immune tolerance in hepatocellular carcinoma. Forkhead box P3-peptide inhibitor P60 has been shown to specifically inhibit regulatory T-cell function in murine models. Aim of this study was to investigate whether P60 can improve the immune response induced by vaccination with adenovirus-transduced dendritic cells expressing alpha-fetoprotein in subcutaneous and orthotopic murine models for hepatocellular carcinoma. METHODS: Mice developing subcutaneous or orthotopic HCC received daily treatment with P60 starting at different tumor stages. Additionally, mice were vaccinated twice with dendritic cells expressing alpha-fetoprotein. RESULTS: In a preventive setting prior to tumor engraftment, vaccination with alpha-fetoprotein-expressing dendritic cells significantly decreased tumor growth in a subcutaneous model (p = .0256), but no further effects were achieved by addition of P60. However, P60 enhanced the antitumoral effect of a vaccination with alpha-fetoprotein-expressing dendritic cells in established subcutaneous and orthotopic hepatocellular carcinoma characterized by high Treg levels (p = .011). CONCLUSION: In this study, we showed that vaccination with alpha-fetoprotein-expressing dendritic cells in combination with a specific inhibition of regulatory T-cells by using P60 leads to synergistic tumor inhibition and prolonged survival. This emphasizes the importance of regulatory T-cells inhibition for obtaining an effective antitumoral immune response in hepatocellular carcinoma.

Surgical treatment for pancreatic cystic lesions-implications from the multi-center and prospective German StuDoQ|Pancreas registry.

PURPOSE: The detection of pancreatic cystic lesions (PCL) causes uncertainty for physicians and patients, and international guidelines are based on low evidence. The extent and perioperative risk of resections of PCL in Germany needs comparison with these guidelines to highlight controversies and derive recommendations. METHODS: Clinical data of 1137 patients who underwent surgery for PCL between 2014 and 2019 were retrieved from the German StuDoQ|Pancreas registry. Relevant features for preoperative evaluation and predictive factors for adverse outcomes were statistically identified. RESULTS: Patients with intraductal papillary mucinous neoplasms (IPMN) represented the largest PCL subgroup (N = 689; 60.6%) while other entities (mucinous cystic neoplasms (MCN), serous cystic neoplasms (SCN), neuroendocrine tumors, pseudocysts) were less frequently resected. Symptoms of pancreatitis were associated with IPMN (OR, 1.8; P = 0.012) and pseudocysts (OR, 4.78; P < 0.001), but likewise lowered the likelihood of MCN (OR, 0.49; P = 0.046) and SCN (OR, 0.15, P = 0.002). A total of 639 (57.2%) patients received endoscopic ultrasound before resection, as recommended by guidelines. Malignancy was histologically confirmed in 137 patients (12.0%), while jaundice (OR, 5.1; P < 0.001) and weight loss (OR, 2.0; P = 0.002) were independent predictors. Most resections were performed by open surgery (N = 847, 74.5%), while distal lesions were in majority treated using minimally invasive approaches (P < 0.001). Severe morbidity was 28.4% (N = 323) and 30d mortality was 2.6% (N = 29). Increased age (P = 0.004), higher BMI (P = 0.002), liver cirrhosis (P < 0.001), and esophageal varices (P = 0.002) were independent risk factors for 30d mortality. CONCLUSION: With respect to unclear findings frequently present in PCL, diagnostic means recommended in guidelines should always be considered in the preoperative phase. The therapy of PCL should be decided upon in the light of patient-specific factors, and the surgical strategy needs to be adapted accordingly.

Machine Learning for Decision-Support in Acute Abdominal Pain - Proof of Concept and Central Considerations.

Acute abdominal pain is a common presenting symptom in the emergency department and represents heterogeneous causes and diagnoses. There is often a decision to be made regarding emergency surgical care. Machine learning (ML) could be used here as a decision-support and relieve the time and personnel resource shortage.Patients with acute abdominal pain presenting to the Department of Surgery at Bonn University Hospital in 2020 and 2021 were retrospectively analyzed. Clinical parameters as well as laboratory values were used as predictors. After randomly splitting into a training and test data set (ratio 80 to 20), three ML algorithms were comparatively trained and validated. The entire procedure was repeated 20 times.A total of 1357 patients were identified and included in the analysis, with one in five (n = 276, 20.3%) requiring emergency abdominal surgery within 24 hours. Patients operated on were more likely to be male (p = 0.026), older (p = 0.006), had more gastrointestinal symptoms (nausea: p < 0.001, vomiting p < 0.001) as well as a more recent onset of pain (p < 0.001). Tenderness (p < 0.001) and guarding (p < 0.001) were more common in surgically treated patients and blood analyses showed increased inflammation levels (white blood cell count: p < 0.001, CRP: p < 0.001) and onset of organ dysfunction (creatinine: p < 0.014, quick p < 0.001). Of the three trained algorithms, the tree-based methods (h2o random forest and cforest) showed the best performance. The algorithms classified patients, i.e., predicted surgery, with a median AUC ROC of 0.81 and 0.79 and AUC PRC of 0.56 in test sets.A proof-of-concept was achieved with the development of an ML model for predicting timely surgical therapy for acute abdomen. The ML algorithm can be a valuable tool in decision-making. Especially in the context of heavily used medical resources, the algorithm can help to use these scarce resources more effectively. Technological progress, especially regarding artificial intelligence, increasingly enables evidence-based approaches in surgery but requires a strictly interdisciplinary approach. In the future, the use and handling of ML should be integrated into surgical training.

Machine learning to guide clinical decision-making in abdominal surgery-a systematic literature review.

PURPOSE: An indication for surgical therapy includes balancing benefits against risk, which remains a key task in all surgical disciplines. Decisions are oftentimes based on clinical experience while guidelines lack evidence-based background. Various medical fields capitalized the application of machine learning (ML), and preliminary research suggests promising implications in surgeons' workflow. Hence, we evaluated ML's contemporary and possible future role in clinical decision-making (CDM) focusing on abdominal surgery. METHODS: Using the PICO framework, relevant keywords and research questions were identified. Following the PRISMA guidelines, a systemic search strategy in the PubMed database was conducted. Results were filtered by distinct criteria and selected articles were manually full text reviewed. RESULTS: Literature review revealed 4,396 articles, of which 47 matched the search criteria. The mean number of patients included was 55,843. A total of eight distinct ML techniques were evaluated whereas AUROC was applied by most authors for comparing ML predictions vs. conventional CDM routines. Most authors (N = 30/47, 63.8%) stated ML's superiority in the prediction of benefits and risks of surgery. The identification of highly relevant parameters to be integrated into algorithms allowing a more precise prognosis was emphasized as the main advantage of ML in CDM. CONCLUSIONS: A potential value of ML for surgical decision-making was demonstrated in several scientific articles. However, the low number of publications with only few collaborative studies between surgeons and computer scientists underpins the early phase of this highly promising field. Interdisciplinary research initiatives combining existing clinical datasets and emerging techniques of data processing may likely improve CDM in abdominal surgery in the future.

Induction of cytotoxic effector cells towards cholangiocellular, pancreatic, and colorectal tumor cells by activation of the immune checkpoint CD40/CD40L on dendritic cells.

INTRODUCTION: Gastrointestinal (GI) malignancies, such as cholangiocarcinoma, pancreatic carcinoma, and metastatic colorectal carcinoma, have a poor prognosis and effective therapeutic approaches are still challenging. Checkpoint inhibition with PD-1 or PDL-1 antibodies revealed promising results in different tumor entities; however, only few patients with GI tumors can potentially benefit from PD1/PDL1 inhibiting immunotherapy. Further immunotherapeutic strategies for GI malignancies are urgently needed. The aim of this study was to demonstrate that in vitro activation of the immune checkpoint CD40/CD40L can improve DC action towards bile duct, pancreas, and colorectal carcinoma. METHODS: Human DC were isolated from buffy coats from healthy donors, pulsed with tumor lysates and then transduced with adenoviruses encoding human CD40L (Ad-hCD40L). Using transwell assays, the effects of (m)CD40L on DC immunoactivation compared to (s)CD40L were analyzed. Surface marker and cytokine/chemokine expression were measured by flow cytometry, ELISA and cytokine arrays. Capacity of Ad-hCD40L-transduced DC to induce tumor-specific effector cells was tested using MTT proliferation assay and cytotoxicity assays. Apoptosis induction on tumor cells after culturing with supernatants of Ad-hCD40L-transduced DC was analyzed by flow cytometry. RESULTS: Ad-hCD40L transduction induced a high expression of (s)CD40L and (m)CD40L on DC and seemed to induce a strong cellular CD40/CD40L interaction among DC, leading to the formation of cell aggregates. Due to the CD40/CD40L interaction, a significant upregulation of DC maturation markers and a Th1-shift on cytokines/chemokines in the supernatant of DC were achieved. Interestingly, a pure Th1-shift was only achieved, when a cellular CD40/CD40L interaction among DC took place. (s)CD40L induced almost no upregulation of maturation markers and rather resulted in a Th2-cytokine expression, such as IL-10. Correspondingly, (m)CD40L-expressing DC led to significant proliferation and stimulation of tumor-specific effector cells with increased cytotoxicity towards pancreatic, bile duct and colorectal tumor cells. Supernatants of Ad-hCD40L-transduced DC could also induce apoptosis in the different tumor cells in vitro. CONCLUSION: Stimulation of the immune checkpoint CD40L/CD40 by endogenous expression of (m)CD40L provokes a cellular interaction, which increases the immunomodulatory capacity of DC. A Th1 cytokine/chemokine expression is induced, leading to a significant proliferation and enabling cytotoxicity of effector cells towards human bile duct, pancreatic and colorectal tumor cells. The present data point to the promising approach for DC-based immunotherapy of gastrointestinal malignances by activating the CD40/CD40L immune checkpoint.

Management of post-operative pancreatic fistulas following Longmire-Traverso pylorus-preserving pancreatoduodenectomy by endoscopic vacuum-assisted closure therapy.

BACKGROUND: Pylorus-preserving pancreatoduodenectomy (PPPD) with pancreatogastrostomy is a standard surgical procedure for pancreatic head tumors, duodenal tumors and distal cholangiocarcinomas. Post-operative pancreatic fistulas (POPF) are a major complication causing relevant morbidity and mortality. Endoscopic vacuum therapy (EVT) has become a widely used method for the treatment of intestinal perforations and leakages. Here we report on a pilot single center series of 8 POPF cases specifically caused by dehiscences of the pancreatogastric anastomosis (PGD), successfully managed by EVT. METHODS: We included all patients with PGD after PPPD, who were treated with EVT between 07/2017 and 08/2020. For EVT a vacuum drainage film (EVT film) or open-pore polyurethane foam sponge (EVT sponge) was fixed to a 14Fr or 16Fr suction catheter and placed endoscopically within the PGD for intracavitary EVT with continuous suction between - 100 and - 150 mmHg. The EVT film/sponge was exchanged twice per week. EVT was discontinued when the PGD was sufficiently healed. RESULTS: PGD closure was achieved in 7 of 8 patients after a mean EVT time of 16 days (range 8-38) and 3 EVT film/sponge exchanges (range 1-9). One patient died on day 18 after PPPD from acute hemorrhagic shock, unlikely related to EVT, before effectiveness of EVT could be fully achieved. There were no adverse events directly attributable to EVT. CONCLUSIONS: EVT could be an effective and safe addition to our therapeutic armamentarium in the management of POPF with PGD. Unless prospective comparative studies are available, EVT as minimally invasive therapeutic alternative should be considered individually by an interdisciplinary team involving endoscopists, surgeons and radiologists.

Programmed cell death protein 1 (PD-1)-inhibition in hepatocellular carcinoma (HCC): a single center experience.

BACKGROUND: The prognosis for advanced Hepatocellular carcinoma (HCC)is still very poor. Despite initial usefulness of immune checkpoint inhibitor (PD-1), phase 3 trials failed to show significant benefit of PD-1 inhibition with nivolumab or pembrolizumab in the first and second line therapy of HCC. Clinical evidence of PD-1 inhibition in patients with advanced and heavily pretreated HCC outside clinical trials is extremely limited. In this study, we analyzed the clinical experience with PD-1 inhibition in patients with heavily pretreated HCC. METHODS: Between May 2016 and January 2019 14 patients with advanced and heavily pretreated HCC were treated with nivolumab or pembrolizumab at the University Hospital Bonn, Germany. Base line characteristics prior to immunotherapy, immunohistochemistry of different immunological markers, beneficial outcome and safety were recorded and retrospectively analyzed. RESULTS: Immunotherapy with PD-1 inhibition was well tolerated and resulted in significant clinical benefit as last line therapy. Median overall survival (OS) was 6.6 months (95%CI:3.9-11.8), progression-free survival (PFS) was 5.3 months (95%CI:2.4-11.7) and overall response rate (ORR) was 30.8%. One patient reached a complete remission. CONCLUSIONS: Despite numerous pretreatments, PD-1 inhibition was well tolerated and showed clinical benefit in patients with heavily pretreated HCC.

Acute mesenteric ischemia (AMI): absence of renal insufficiency and performance of early bowel resection may indicate improved outcomes.

PURPOSE: Acute mesenteric ischemia (AMI) is still associated with very high morbidity and mortality while the rareness and heterogeneity hamper the establishment of evidence-based guidelines. We sought to help standardize contemporary treatment by a cohort study at our tertiary center in the rising endovascular age. METHODS: A retrospective cohort study was conducted from 2005 to 2015. Patients with occlusive (OMI), non-occlusive (NOMI), and venous mesenteric ischemia (VMI) were compared with respect to clinical and treatment parameters as well as outcome. RESULTS: The study cohort consisted of 48 patients composed of 27 males and 21 females with an average age of 63 years and an average BMI of 25.1 kg/m2. In 48% of patients (N=23), an acute arterial OMI had occurred while NOMI was present in 31% (N=15) and VMI in 21% (N=10). Interventional and intraoperative recanalizations were significantly more often required in OMI patients compared with other entities (p=0.003). Patients with venous mesenteric ischemia had a significant better overall survival than patients with OMI or NOMI in the univariate analysis (p=0.027). Patients with renal failure had a 14.7-fold higher relative risk (Cox p=0.013) and patients without bowel resection during primary surgery had a 17.8-fold higher relative risk (Cox p=0.047) to die of AMI in the postoperative course. CONCLUSIONS: AMI remains a rare but oftentimes fatal disease. Our study provides evidence that outcome may depend on the AMI subtype, presence of renal insufficiency, and early bowel resection. Further research should help individualize treatment for optimized outcomes.

[Current and Future Role of Vascular Surgery Expertise for Visceral Surgeons - an Expert Survey]. / Aktueller und künftiger Stellenwert der gefäßchirurgischen Expertise für Viszeralchirurgen ­ eine Expertenbefragung.

BACKGROUND: Due to improved surgical techniques and safer perioperative management, there has been an increase in radical abdominal and oncological operations. Simultaneous vascular interventions are increasingly necessary - either after preoperative planning or after an intraoperative vascular emergency. It is unclear whether German visceral surgeons have the required vascular surgical skills. An assessment of the current and future status of vascular techniques within visceral surgery is therefore the issue of the present survey. METHODS: A questionnaire was sent to the chairs of visceral surgery of German university hospitals and to the directors of non-academic surgical departments in 2017. Thus, we sought to assess the current and future status of vascular surgery within abdominal and oncological operations. There were person-, hospital-, system-, and intervention-related questions to be answered. RESULTS: Compared to non-academic hospitals, significantly more vascular interventions were performed within abdominal surgery at university hospitals (p < 0.001), where generally more such expertise is available. Surgical support from vascular surgeons is present in a majority of both academic and non-academic institutions (72.8%). However, almost one third of respondents expressed a desire for more vascular surgery expertise at their departments. An optional rotation in vascular surgery exists predominantly at university hospitals (92.9 vs. 73.8%; p = 0.031). A slim majority of all surgical managers assumes that vascular surgery will play an increasing role in the future of visceral and oncological surgery (51.6%) and favours obligatory rotation for visceral surgery residents of at least six months (54.1%). Necessary skills to be taught include thrombectomy and embolectomy (95.6%), vascular suture (98.6%) and patch (89.1%) as well as vascular bypass surgery (45.5%). CONCLUSIONS: There is an expert consensus that vascular surgery is of increasing significance for visceral surgeons. In spite of the possibility of optional rotations for residents at most hospitals, there seems to be a demand for more expertise in vascular surgery at several departments. Obligatory rotation in vascular surgery should be discussed within training programs for visceral surgery.

[Have Multimodal and Perioperative Therapeutic Strategies Changed the Survival after Oncological Oesophageal Surgery in the Last Two Decades? A Retrospective Cohort Analysis over 23 Years]. / Haben multimodale und perioperative Therapiestrategien das Überleben nach onkologischer Ösophaguschirurgie in den letzten 2 Dekaden verändert? Eine retrospektive Kohortenanalyse über 23 Jahre.

BACKGROUND: Esophageal malignoma is among the most frequent causes for cancer-related deaths. The only definite curative therapy is esophagectomy embedded in various multimodal treatment regimens. The aim of this study was to evaluate long-term development after esophageal surgery in the last two decades in order to observe possible trends and their influence on short, medium and long term survival. PATIENTS AND METHODS: Cases of 301 patients who underwent esophagectomy between 1989 and 2012 were analysed retrospectively. To investigate possible changes in perioperative management and their influence on prognosis patients were divided into two cohorts (A: surgery between 1989 and 2000; B: surgery between 2001 and 2012) and further analyzed with regard to demographics, tumor entity, stage, complications and survival. Statistics were conducted to compare both groups while p ≤ 0.05 was regarded as statistically significant. RESULTS: In cohort B patients were significantly older compared to cohort A and underwent surgery in earlier tumor stages with a higher lymphnode yield. Also an increased incidence of adenocarcinoma was observed. While overall morbidity did not change significantly, a decreased rate of anastomotic leakage was observed in cohort B (5.5%) compared to cohort A (12.3%) accompanied by a simultaneous increase in cardiac events (A: 3.6% vs. B: 12.3%). Overall 30-days-mortality was 2.7% and decreased significantly from 5% in cohort A to 0.7% in cohort B (p = 0.05). Median survival was 46 ± 7 month in cohort A, in cohort B an increase could be observed (53 ± 7 months, p = 0.03). By univariate analysis we could demonstrate that stage, affected lymph nodes, lymphnode ratio (LNR) and incidence of postoperative complications were significant predictors for the survival whereas in multivariate analysis T-stage, R-status and LNR were independent predictors for patients outcome. CONCLUSION: Patients undergoing esophageal resection for cancer nowadays are older than in the past decades. Earlier cancer diagnosis, more radical surgical techniques with an extended lymphnode dissection, a decrease in anastomotic leakage and an improved perioperative care seem to compensate for this potential demographic disadvantage. The most important independent predictor of outcome after esophageal resection is the LNR.

Advantages of laparoscopic compared to conventional surgery are not related to an innate immune response of peritoneal immune activation: an animal study in rats.

PURPOSE: Laparoscopic surgery (LS) has proved superior compared to conventional surgery (CS) regarding morbidity, length of hospital stay, rate of wound infection and time until recovery. An improved preservation of the postoperative immune function is assumed to contribute to these benefits though the role of the local peritoneal immune response is still poorly understood. Our study investigates the peritoneal immune response subsequent to abdominal surgery and compares it between laparoscopic and conventional surgery to find an immunological explanation for the clinically proven benefits of LS. METHODS: Wistar rats (N = 140) underwent laparoscopic cecum resection (LCR; N = 28), conventional cecum resection (CCR; N = 28), laparoscopic sham operation (LSO; N = 28), conventional sham operation (CSO; N = 28), or no surgical treatment (CTRL; N = 28). Postoperatively, peritoneal lavages were performed, leukocytes isolated and analyzed regarding immune function and phagocytosis activity. RESULTS: Immune function was inhibited postoperatively in animals undergoing LCR or CCR compared to CTRL reflected by a lower TNF-α (CTRL 3956.65 pg/ml, LCR 2018.48 pg/ml (p = 0.023), CCR 2793.78 pg/ml (n.s.)) and IL-6 secretion (CTRL 625.84 pg/ml, LCR 142.84 pg/ml (p = 0.009), CCR 169.53 pg/ml (p = 0.01)). Phagocytosis was not affected in rats undergoing any kind of surgery compared to CTRL. Neither cytokine secretion nor phagocytosis activity differed significantly between laparoscopic and conventional surgery. CONCLUSIONS: According to our findings the benefits associated with LS compared to CS cannot be explained by differences in the postoperative peritoneal innate immune response. Further studies are needed to elucidate the causes for a more favorable postoperative outcome in patients after LS compared to CS.

Delayed gastric emptying following pancreatoduodenectomy with alimentary reconstruction according to Roux-en-Y or Billroth-II.

BACKGROUND: Delayed gastric emptying (DGE) remains the most frequent complication following pancreatoduodenectomy (PD) with published incidences as high as 61%. The present study investigates the impact of bowel reconstruction techniques on DGE following classic PD (Whipple-Kausch procedure) with pancreatogastrostomy (PG). METHODS: We included 168 consecutive patients who underwent PD with PG with either Billroth II type (BII, n = 78) or Roux-en-Y type reconstruction (ReY, n = 90) between 2004 and 2015. Excluded were patients with conventional single loop reconstruction after pylorus preserving procedures. DGE was classified according to the 2007 International Study Group of Pancreatic Surgery definition. Patients were analyzed regarding severity of DGE, morbidity and mortality, length of hospital stay and demographic factors. RESULTS: No difference was observed between BII and ReY regarding frequency of DGE. Overall rate for clinically relevant DGE was 30% (ReY) and 26% (BII). BII and ReY did not differ in terms of demographics, morbidity or mortality. DGE significantly prolongs ICU (four vs. two days) and hospital stay (20.5 vs. 14.5 days). Risk factors for DGE development are advanced age, retrocolic reconstruction, postoperative hemorrhage and major complications. CONCLUSIONS: The occurrence of DGE can not be influenced by the type of alimentary reconstruction (ReY vs. BII) following classic PD with PG. Old age and major complications could be identified as important risk factors in multivariate analysis. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) DRKS00011860 . Registered 14 March 2017.

[Vascular Complications and Emergencies within Oncologic Abdominal Surgery - What Knowledge and Skills Are Essential for the Visceral Surgeon]. / Vaskuläre Komplikationen und Notfälle in der onkologischen Viszeralchirurgie ­ was muss ein Viszeralchirurg können und wissen.

Background Continuous improvements in perioperative and neoadjuvant therapy concepts nowadays permit more extensive tumor resections with curative intention. In patients with arterial or venous tumour involvement in preoperative imaging, physicians with expertise in vascular surgery should be involved in the planning phase of the operation. Unexpected vascular complications during abdominal surgery demand prompt management by the oncological surgeon. However, skills in vascular surgery are still not obligatory for the visceral surgeon in training. This topic is controversial and is therefore the focus of the present study. Patients and Methods From 2010 - 2015, a total of 126 patients underwent visceral operations involving vascular surgical interventions. Of these, 30 operations were performed as radical tumour resections. Retrospective data acquisition was performed with a minimum follow-up of 12 months. Aside from comprehensive characterisation of patients and their diseases, an outcome analysis was conducted. Furthermore, visceral surgery training programs in accordance with all 17 German federal medical associations were analysed and compared with respect to vascular surgery teaching. Results Vascular surgery was necessary in most patients, due to lesions of the mesentericoportal venous system (n = 11; 37%) and visceral arteries (n = 14; 47%). Techniques involved were mostly vascular sutures, reanastomosis or patch plastic surgery (n = 19; 63%) and venous thrombectomy/arterial embolectomy (n = 18; 60%). Hospital mortality was 3%. During follow-up, 33% of oncological patients died, whereas solely venous injury was an independent adverse prognostic variable (arterial vs. venous complications: HR 0.028; 95%-CI 0.002 - 0.442; p = 0.01). Skills in vascular surgery are optional for up to 12 months within visceral surgery training. Conclusions Intraoperative vascular complications in visceral surgical oncology are rare but pose severe risks for the patients. Their management requires basic knowledge and skills in vascular anatomy, preparation and skills to ensure immediate safe control of bleeding, as well as suture techniques and interposition grafts. Current training and specialisation in visceral surgery does not include obligatory vascular surgery teaching, so that this issue needs reevaluation.

[Prognostic Factors of Open Abdomen Treatment in Visceral Surgery]. / Prognosefaktoren der offenen Abdominalbehandlung in der Viszeralchirurgie.

Introduction In general surgery, open abdomen treatment (OAT) is used to treat abdominal compartment syndrome (ACS) and sepsis, often after a primary surgical procedure associated with complications. The results achieved in this patient population may depend on factors that are yet unknown. This study evaluates independent patient-related prognostic factors after OAT. Methods 38 clinical parameters and survival data of 165 consecutive general surgery patients after OAT were entered into a prospective database according to a defined algorithm in order to analyse the underlying surgical pathology, predictors of survival and important aspects of OAT-related morbidity. Independent predictors of survival, OAT-related morbidity and duration of hospital stay were identified. Results Common indications for OAT were peritonitis, haemorrhage and ACS. Median age was 60 years and > 80 % of patients were ASA III/IV; median follow-up was 23 months. Oncologic surgery was performed in 19 % of cases. 30-day and 1-year mortality was 11 % and 34 %, respectively. Malignancy was a negative predictor (OR: 4.63, 95 % CI: 2.00-10.7) while mild obesity (BMI 25-35) and primary fascial closure, which was achieved in 82 % of patients, improved survival (OR: 0.2, 95 % CI: 0.07-0.55; OR: 0.19, 95 % CI: 0.06-0.57). Enteroatmospheric fistula (EAF) and giant hernia with impossible fascial closure were frequent after OAT (19 and 18 %), and malignancy was an independent risk factor for EAF (OR 3.47, CI [95 %]: 1.41-8.53). Vacuum-assisted wound closure or polyglactin mesh interposition did not affect EAF incidence. Conclusions General surgery patients after OAT differ significantly from trauma patients, and mortality as well as long-term morbidity is high. Outcome is greatly determined by independent patient-related factors after OAT. A tailored surgical approach based on objective evidence is needed to further improve the results after OAT.

Pathologic Evaluation and Reporting of Intraductal Papillary Mucinous Neoplasms of the Pancreas and Other Tumoral Intraepithelial Neoplasms of Pancreatobiliary Tract: Recommendations of Verona Consensus Meeting.

BACKGROUND: There are no established guidelines for pathologic diagnosis/reporting of intraductal papillary mucinous neoplasms (IPMNs). DESIGN: An international multidisciplinary group, brought together by the Verona Pancreas Group in Italy-2013, was tasked to devise recommendations. RESULTS: (1) Crucial to rule out invasive carcinoma with extensive (if not complete) sampling. (2) Invasive component is to be documented in a full synoptic report including its size, type, grade, and stage. (3) The term "minimally invasive" should be avoided; instead, invasion size with stage and substaging of T1 (1a, b, c; ≤ 0.5, > 0.5-≤ 1, > 1 cm) is to be documented. (4) Largest diameter of the invasion, not the distance from the nearest duct, is to be used. (5) A category of "indeterminate/(suspicious) for invasion" is acceptable for rare cases. (6) The term "malignant" IPMN should be avoided. (7) The highest grade of dysplasia in the non-invasive component is to be documented separately. (8) Lesion size is to be correlated with imaging findings in cysts with rupture. (9) The main duct diameter and, if possible, its involvement are to be documented; however, it is not required to provide main versus branch duct classification in the resected tumor. (10) Subtyping as gastric/intestinal/pancreatobiliary/oncocytic/mixed is of value. (11) Frozen section is to be performed highly selectively, with appreciation of its shortcomings. (12) These principles also apply to other similar tumoral intraepithelial neoplasms (mucinous cystic neoplasms, intra-ampullary, and intra-biliary/cholecystic). CONCLUSIONS: These recommendations will ensure proper communication of salient tumor characteristics to the management teams, accurate comparison of data between analyses, and development of more effective management algorithms.

Value and risk of laparoscopic surgery in hemophiliacs-experiences from a tertiary referral center for hemorrhagic diatheses.

PURPOSE: Laparoscopic surgery (LS) is gaining popularity worldwide because of benefits like faster recovery, earlier hospital discharge, and better cosmetic results. In hemophiliacs, surgery in general harbors an increased risk for severe complications. Whether LS or conventional surgery (CS) should be recommended in these patients is controversial and therefore the issue of our present study. METHODS: We performed a retrospective matched-pair analysis including laparoscopically operated non-hemophiliacs (LONH), laparoscopically operated hemophiliacs (LOH), and conventionally operated hemophiliacs (COH) concerning duration of surgery, drainages, hospital stay, complications, factor use (VIII, IX, and X), and blood values. Mann-Whitney U test was used (significance level P = 0.05). RESULTS: No significant differences were found in duration of surgery and drains in laparoscopically or conventionally operated hemophiliacs versus matched pairs. Complication rate did not differ among the different groups. Concerning the total duration of hospital stay (t-DHOS) and the postoperative duration of hospital stay (p-DHOS), there was no statistical difference between LOH versus matched LONH. However, in COH versus matched LOH, a longer time was required for preparation and recovery (t-DHOS, P = 0.04; p-DHOS, P < 0.001). Also, the median factor supply perioperatively including the day of surgery did not differ between laparoscopically versus conventionally operated hemophiliacs. CONCLUSIONS: Our study underscores the safety and benefits of laparoscopic procedures in hemophiliacs by showing a significantly shorter hospital stay for these patients resulting in reduced therapeutic costs and a faster mobilization. Still, the surgical and perioperative management of hemophiliacs continues to be a challenge requiring an experienced interdisciplinary team.

Mutant proteins as cancer-specific biomarkers.

Cancer biomarkers are currently the subject of intense research because of their potential utility for diagnosis, prognosis, and targeted therapy. In theory, the gene products resulting from somatic mutations are the ultimate protein biomarkers, being not simply associated with tumors but actually responsible for tumorigenesis. We show here that the altered protein products resulting from somatic mutations can be identified directly and quantified by mass spectrometry. The peptides expressed from normal and mutant alleles were detected by selected reaction monitoring (SRM) of their product ions using a triple-quadrupole mass spectrometer. As a prototypical example of this approach, we demonstrated that it is possible to quantify the number and fraction of mutant Ras protein present in cancer cell lines. There were an average of 1.3 million molecules of Ras protein per cell, and the ratio of mutant to normal Ras proteins ranged from 0.49 to 5.6. Similarly, we found that mutant Ras proteins could be detected and quantified in clinical specimens such as colorectal and pancreatic tumor tissues as well as in premalignant pancreatic cyst fluids. In addition to answering basic questions about the relative levels of genetically abnormal proteins in tumors, this approach could prove useful for diagnostic applications.

Expression of the large amino acid transporter SLC7A5/LAT1 on immune cells is enhanced in primary sclerosing cholangitis-associated cholangiocarcinoma and correlates with poor prognosis in cholangiocarcinoma.

Biliary tract cancers (BTC) are rare lethal malignancies arising along the biliary tree. Unfortunately, effective therapeutics are lacking and the prognosis remains dismal even for patients eligible for surgical resection. Therefore, novel therapeutic approaches along with early detection strategies and prognostic markers are urgently needed. Primary sclerosing cholangitis (PSC) is a chronic disease of the bile ducts leading to fibrosis and ultimately cirrhosis. Patients with PSC have a 5-20% lifetime risk of developing BTC; yet the molecular mechanisms that underpin the development of PSC- associated biliary tract cancer (PSC-BTC) have not been fully elucidated. SLC7A5/LAT1, a large amino acid transporter, has been shown to modulate cell growth and proliferation as well as other intracellular processes in solid tumors. In this study, we evaluated SLC7A5 expression in PSC-BTC and in sporadic BTC (sBTC) and its role as a prognostic factor. Analysis of the TGCA cohort showed a significantly higher expression of SLC7A5 in tumor tissue compared with adjacent normal tissue (p = 0.0002) in BTC. In our cohort (comprised of 69 BTC patients including 16 PSC-BTC), SLC7A5/LAT1 expression was observed in both tumor and intratumoral immune cells. A significantly higher percentage of SLC7A5/LAT1 positive intratumoral immune cells was observed in PSC-BTC compared with sBTC (p = 0.004). Multiplex immunofluorescence co-detection by indexing (CODEX) analysis identified CD4+ regulatory T lymphocytes and CD68+ macrophages as the largest immune cell populations expressing LAT1. SLC7A5/LAT1 expression as well as a higher intratumoral infiltration of SLC7A5/LAT1-positive immune cells (≥2%) were associated with a shorter overall survival in our cohort (LogRank test, p = 0.04 and p = 0.008; respectively). SLC7A5/LAT1 expressing tumors are higher staged tumors (pT3/4 versus pT1/2, p = 0.048). These results underline the potential use of SLC7A5/LAT1 as a prognostic marker in BTC. Furthermore, the higher frequency of SLC7A5/LAT1 positive immune cells in PSC-BTC compared to sBTC may hint at the potential role of SLC7A5/LAT1 in inflammation-driven carcinogenesis.