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.

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.

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.

Comparison between regular additional endobiliary radiofrequency ablation and photodynamic therapy in patients with advanced extrahepatic cholangiocarcinoma under systemic chemotherapy.

Background and aims: Extrahepatic cholangiocarcinoma (eCCA) remains a malignancy with a dismal prognosis. The first-line standard of care includes systemic chemotherapy (SC) and biliary drainage through stenting. Endobiliary ablative techniques, such as photodynamic therapy (ePDT) and radio-frequency ablation (eRFA), have demonstrated feasibility and favorable survival data. This study aimed to compare the oncologic outcome in patients treated with SC and concomitant eRFA or ePDT. Method: All patients with eCCA were evaluated for study inclusion. Sixty-three patients receiving a combination of SC and at least one endobiliary treatment were retrospectively compared. Results: Patients were stratified into three groups: SC + ePDT (n = 22), SC + eRFA (n = 28), and SC + ePDT + eRFA (n = 13). The median overall survival (OS) of the whole cohort was 14.2 months with no statistically significant difference between the three therapy groups but a trend to better survival for the group receiving ePDT as well as eRFA, during SC (ePDT + SC, 12.7 months; eRFA + SC, 13.8 months; ePDT + eRFA + SC, 20.2 months; p = 0.112). The multivariate Cox regression and subgroup analysis highlighted the beneficial effect of eRFA on OS. Overall, combined therapy was well tolerated. Only cholangitis occurred more often in the SC + eRFA group. Conclusion: Additional endobiliary ablative therapies in combination with SC were feasible. Both modalities, eRFA and ePDT, showed a similar benefit in terms of survival. Interestingly, patients receiving both regimes showed the best OS indicating a possible synergism between both ablative therapeutic techniques.

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.

Assessing the Effects of a Perioperative Nutritional Support and Counseling in Gastrointestinal Cancer Patients: A Retrospective Comparative Study with Historical Controls.

The aim of this study was to investigate the effects of perioperative nutritional therapy care in gastrointestinal (esophageal, gastric, gastroesophageal) cancer patients on nutritional status and disease progression (complications, hospitalization, mortality). We considered 62 gastrointestinal cancer patients treated at the Center for Integrated Oncology (CIO), University Hospital Bonn, Germany (August 2017-July 2019). Of these, 42 patients (as intervention group: IG) received pre- and postoperative nutritional support with counseling, while 20 patients (as historical control group CG) received only postoperative nutritional therapy. Several clinical parameters, such as Body Mass Index (BMI), nutritional risk screening (NRS), phase angle, postoperative complications, length of hospital stay, and mortality, were determined. There were significantly fewer patients with gastric cancer/CDH1 gene mutation and more with esophageal cancer in IG (p = 0.001). Significantly more patients received neoadjuvant therapy in IG (p = 0.036). No significant differences were found between the groups regarding BMI, NRS, complications, length of hospital stay, and mortality. However, the comparison of post- and preoperative parameters in IG showed a tendency to lose 1.74 kg of weight (p = 0.046), a decrease in phase angle by 0.59° (p = 0.004), and an increase in NRS of 1.34 points (p < 0.001). Contrary to prior reports, we found no significant effect of perioperative nutritional therapy care in gastrointestinal cancer patients; however, the small cohort size and infrequent standardization in nutritional status may possibly account for the variance. Considering that oncological pathways and metabolic nutritional pathways are interrelated, dividing patients into subgroups to provide a personalized nutritional approach may help in improving their treatment.

Clinically Relevant Pancreatic Fistula after Pancreaticoduodenectomy: How We Do It.

(1) Background: This study's goals were to investigate possible risk factors for clinically relevant postoperative pancreatic fistula (POPF) grade B/C according to the updated definitions of the International Study Group of Pancreatic Surgery and to analyze possible treatment strategies; (2) Methods: Between 2017 and 2021, 200 patients were analyzed regarding the development of POPF grade B/C with an emphasis on postoperative outcome and treatment strategies; (3) Results: POPF grade B/C was observed in 39 patients (19.5%). These patients were younger, mainly male, had fewer comorbidities and showed a higher body mass index. Also, they had lower CA-19 levels, a smaller tumor size and softer pancreatic parenchyma. They experienced a worse outcome without affecting the overall mortality rate (10% vs. 6%, p = 0.481), however, this lead to a prolonged postoperative stay (28 (32-36) d vs. 20 (15-28) d, p ≤ 0.001). The majority of patients with POPF grade B/C were able to receive conservative treatment, followed by drainage placement, endoscopic vacuum-assisted therapy (EVT) and surgery. Conservative treatment resulted in a shorter length of the postoperative stay (24 (22-28) d vs. 34 (26-43) d, p = 0.012); (4) Conclusions: Patients developing POPF grade B/C had a worse outcome; however, this did not affect the overall mortality rate. The majority of the patients were able to receive conservative treatment, resulting in a shorter length of their hospital stay.

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.

The tumour immune microenvironment and microbiome of pancreatic intraductal papillary mucinous neoplasms.

Pancreatic intraductal papillary mucinous neoplasms (IPMNs) have gained substantial attention because they represent one of the only radiographically identifiable precursors of invasive pancreatic ductal adenocarcinoma. Although most of these neoplasms have low-grade dysplasia and will remain indolent, a subset of IPMNs will progress to invasive cancer. The role of the immune system in the progression of IPMNs is unclear, but understanding its role could reveal the mechanism of neoplastic progression and targets for immunotherapy to inhibit progression or treat invasive disease. The available evidence supports a shift in the immune composition of IPMNs during neoplastic progression. Although low-grade lesions contain a high proportion of effector T cells, high-grade IPMNs, and IPMNs with an associated invasive carcinoma lose the T-cell infiltrate and are characterised by a predominance of immunosuppressive elements. Several possible therapeutic strategies emerge from this analysis that are unique to IPMNs and its microbiome.

Postoperative paralytic ileus following debulking surgery in ovarian cancer patients.

Aim: This study aims to evaluate the incidence of postoperative ileus (POI) following cytoreductive surgery in epithelial ovarian cancer (EOC) patients and its impact on anastomotic leakage occurrence and postoperative complications. Methods: A total of 357 surgeries were performed on 346 ovarian cancer patients between 1/2010 and 12/2020 at our institution. The postoperative course regarding paralytic ileus, anastomotic leakage, and postoperative complications was analyzed by Fisher's exact test and through ordinal logistic regression. Results: A total of 233 patients (65.3%) returned to normal gastrointestinal functions within 3 days after surgery. A total of 123 patients (34.5%) developed POI. There were 199 anastomoses in 165 patients and 24 leakages (12.1%). Postoperative antibiotics (p 0.001), stoma creation (p 0.0001), and early start of laxatives (p 0.0048) significantly decreased POI, while anastomoses in general (p 0.0465) and especially low anastomoses (p 0.0143) showed increased POI rates. Intraoperative positive fluid excess >5,000 cc was associated with a higher risk for POI (p 0.0063), anastomotic leakage (p 0.0254), and severe complications (p 0.0012). Conclusion: Postoperative antibiotics, an early start with laxatives, and stoma creation were associated with reduced POI rates. Patients with anastomoses showed an increased risk for POI. Severe complications, anastomotic leakages, and POI were more common in the case of intraoperative fluid balance exceeding 5,000 cc.

Case Report: Sustained complete remission on combination therapy with olaparib and pembrolizumab in BRCA2-mutated and PD-L1-positive metastatic cholangiocarcinoma after platinum derivate.

Cholangiocarcinoma (CCA) still has a poor prognosis and remains a major therapeutic challenge. When curative resection is not possible, palliative systemic chemotherapy with gemcitabine and platinum derivate as first line followed by a 5-FU doublet combination as second line is the standard therapy. Recently, targeted therapy and immunotherapy have rapidly emerged as personalized therapeutic approaches requiring previous tumor sequencing and molecular profiling. BRCA mutations are well-characterized targets for poly (ADP-ribose) polymerase inhibitors (PARPi). However, BRCA gene mutations in CCA are rare and few data of PARPi in the treatment of CCA are available. Immunotherapy with programmed death receptor-1 (PD-1) has been shown to be effective in combination with chemotherapy or in PD-L1-positive CCA. However, data from immunotherapy combined with targeted therapy, including PARPi, are lacking. In this report, we present the case of a male patient with PD-L1-positive and BRCA2-mutated metastatic intrahepatic cholangiocarcinoma, who was treated with a combined therapy with PARP (PARPi), olaparib, and a PD-1 antibody, pembrolizumab, as second-line therapy after gemcitabine/platinum derivate failure. Combined therapy was able to induce a long-lasting complete remission for over 15 months. The combined therapy was feasible and well tolerated. Only mild anemia and immune-related thyroiditis were observed, which were easily manageable and did not result in discontinuation of olaparib and pembrolizumab. Conclusion: The presented case showed substantial clinical activity of a combination with olaparib/pembrolizumab in advanced BRCA2-mutated CCA. Thus, identifying targetable molecular signatures and combinations of targeted therapies with immunotherapy reveals a promising strategy to effectively treat patients with cholangiocarcinoma and should be considered after failure of standard chemotherapy.

Predictors of Morbidity and Mortality After Colorectal Surgery in Patients With Cirrhotic Liver Disease-A Retrospective Analysis of 54 Cases at a Tertiary Care Center.

Background: Despite various existing scores that predict morbidity and mortality of patients with cirrhotic liver disease (CLD), data on specific risk stratification of patients with CLD undergoing colorectal surgery (CRS) are rare. The aim of this study was to assess in-hospital morbidity and mortality of patients with liver cirrhosis scheduled for CRS, with specific focus on possible pitfalls of surgery in this special cohort. Methods: Between 1996 and 2018, 54 patients with CLD undergoing CRS were identified and included in this study cohort. Postoperative morbidity and mortality were assessed using the Clavien/Dindo (C/D) classification as well as by type of complication. Univariate and multivariate analyses were performed to analyze the predictive factors for increased postoperative morbidity. Results: Of the patients, 37% patients died during the procedure or postoperatively. Major complications were seen in 23.1% of patients (>C/D IIIb). Patients with Child B or C cirrhosis as well as patients undergoing emergency surgery experienced significantly more major complications (p = 0.04 and p = 0.023, respectively). The most common complications were bleeding requiring blood transfusion (51.1%) and cardiocirculatory instability due to bleeding or sepsis (44.4%). In 53.7% of patients, an anastomosis was created without a protective ostomy. Anastomotic leakage occurred in 20.7% of these patients. Multivariate analysis showed that a primary anastomosis without a protective ostomy was the strongest risk factor for major complications (p = 0.042). Discussion: Morbidity and mortality after CRS in patients with CLD remains high and is not only influenced by liver function but also by surgical variables. Considering the high rate of anastomotic leakage, creating a protective or definitive ostomy must be considered with regard to the underlying pathology, the extent of CLD, and the patient's condition. Moreover, our data suggest that surgery in these most fragile patients should be performed only in experienced centers with immediate contact to hepatologists and experts in hemostasis.

Diagnostic Potential of Exosomal microRNAs in Colorectal Cancer.

Background: Despite the significance of colonoscopy for early diagnosis of colorectal adenocarcinoma (CRC), population-wide screening remains challenging, mainly because of low acceptance rates. Herein, exosomal (exo-miR) and free circulating microRNA (c-miR) may be used as liquid biopsies in CRC to identify individuals at risk. Direct comparison of both compartments has shown inconclusive results, which is why we directly compared a panel of 10 microRNAs in this entity. Methods: Exo-miR and c-miR levels were measured using real-time quantitative PCR after isolation from serum specimens in a cohort of 69 patients. Furthermore, results were compared to established tumor markers CEA and CA 19-9. Results: Direct comparison of exo- and c-miR biopsy results showed significantly higher microRNA levels in the exosomal compartment (p < 0.001). Exo-Let7, exo-miR-16 and exo-miR-23 significantly differed between CRC and healthy controls (all p < 0.05), while no c-miR showed this potential. Sensitivity and specificity can be further enhanced using combinations of multiple exosomal miRNAs. Conclusions: Exosomal microRNA should be considered as a promising biomarker in CRC for future studies. Nonetheless, results may show interference with common comorbidities, which must be taken into account in future studies.

Obesity Does Not Influence Delayed Gastric Emptying Following Pancreatoduodenectomy.

Background: The data about obesity on postoperative outcome after pancreatoduodenectomy (PD) are inconsistent, specifically in relation to gastric motility and delayed gastric emptying (DGE). Methods: Two hundred and eleven patients were included in the study and patients were retrospectively analyzed in respect to pre-existing obesity (obese patients having a body mass index (BMI) ≥ 30 kg/m2 vs. non-obese patients having a BMI < 30 kg/m2, n = 34, 16% vs. n = 177, 84%) in relation to demographic factors, comorbidities, intraoperative characteristics, mortality and postoperative complications with special emphasis on DGE. Results: Obese patients were more likely to develop clinically relevant pancreatic fistula grade B/C (p = 0.008) and intraabdominal abscess formations (p = 0.017). However, clinically relevant DGE grade B/C did not differ (p = 0.231) and, specifically, first day of solid food intake (p = 0.195), duration of intraoperative administered nasogastric tube (NGT) (p = 0.708), rate of re-insertion of NGT (0.123), total length of NGT (p = 0.471) or the need for parenteral nutrition (p = 0.815) were equally distributed. Moreover, mortality (p = 1.000) did not differ between the two groups. Conclusions: Obese patients do not show a higher mortality rate and are not at higher risk to develop DGE. We thus show that in our study, PD is feasible in the obese patient in regard to postoperative outcome with special emphasis on DGE.

Impact of regular additional endobiliary radiofrequency ablation on survival of patients with advanced extrahepatic cholangiocarcinoma under systemic chemotherapy.

Prognosis of patients with advanced extrahepatic cholangiocarcinoma (eCCA) is poor. The current standard first-line treatment is systemic chemotherapy (CT) with gemcitabine and a platinum derivate. Additionally, endobiliary radiofrequency ablation (eRFA) can be applied to treat biliary obstructions. This study aimed to evaluate the additional benefit of scheduled regular eRFA in a real-life patient cohort with advanced extrahepatic cholangiocarcinoma under standard systemic CT. All patients with irresectable eCCA treated at University Hospital Bonn between 2010 and 2020 were eligible for inclusion. Patients were stratified according to treatment: standard CT (n = 26) vs. combination of eRFA with standard CT (n = 40). Overall survival (OS), progression free survival (PFS), feasibility and toxicity were retrospectively analyzed using univariate and multivariate approaches. Combined eRFA and CT resulted in significantly longer median OS (17.3 vs. 8.6 months, p = 0.004) and PFS (12.9 vs. 5.7 months, p = 0.045) compared to the CT only group. While groups did not differ regarding age, sex, tumor stage and chemotherapy treatment regimen, mean MELD was even higher (10.1 vs. 6.7, p = 0.015) in the eRFA + CT group. The survival benefit of concomitant eRFA was more evident in the subgroup with locally advanced tumors. Severe hematological toxicities (CTCAE grades 3 - 5) did not differ significantly between the groups. However, therapy-related cholangitis occurred more often in the combined treatment group (p = 0.031). Combination of eRFA and systemic CT was feasible, well-tolerated and could significantly prolong survival compared to standard CT alone. Thus, eRFA should be considered during therapeutic decision making in advanced eCCA.

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.

First Line and Second Line Chemotherapy in Advanced Cholangiocarcinoma and Impact of Dose Reduction of Chemotherapy: A Retrospective Analysis.

OBJECTIVE: Prognosis of patients with irresectable cholangiocarcinoma is still poor. The ABC-02 trial established the current first line (1L) standard systemic chemotherapy (CT) with gemcitabine/platinum derivate for advanced cholangiocarcinoma. However, the majority of patients needed therapy adaptions. Thus, the aim of this study was to evaluate 1L and second line (2L) therapy regimens and the impact of therapy adaptions in an unselected real-life cohort of patients with advanced cholangiocarcinoma. MATERIALS AND METHODS: This is a single institution retrospective analysis of patients with irresectable cholangiocarcinoma who were treated with gemcitabine/platinum derivate from 2010 to 2018. Overall survival (OS), progression-free survival (PFS) and toxicity were analyzed for all patients, especially with regard to CT de-escalation. RESULTS: Fifty-eight patients receiving gemcitabine/platinum derivate were included in the analysis. Median OS and PFS were 12.2 and 6.9 months. Interestingly, 41 patients (71%) needed therapy de-escalation. However, despite reduced CT exposition, there was no-significant difference in OS (10.8 months vs. 15.6 months, p = 0.127), and patients suffered from less adverse events during CT. 21 (36%) patients reached 2L CT, most often with FOLFIRI (57%). Survival beyond the end of 1L CT was 7.1 months with 2L CT vs. 2.9 months with BSC. CONCLUSION: In our study, the combination of gemcitabine/platinum derivate showed similar OS and PFS as randomized prospective phase II/III trials. Therapy regimen adaptions were needed in the majority of patients. However, individualized modifications of the therapy regimen allowed better tolerance as well as continuation of therapy and did not significantly influence median OS. Furthermore, our study revealed a potential survival benefit with 2L CT for selected patients.

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.

A Combined TLR7/TLR9/GATA3 Score Can Predict Prognosis in Biliary Tract Cancer.

Biliary tract cancer (BTC) refers to a heterogenous group of epithelial malignancies arising along the biliary tree. The highly aggressive nature combined with its silent presentation contribute to the dismal prognosis of this tumor. Tumor-infiltrating immune cells (TIICs) are frequently present in BTC and there is growing evidence regarding their role as therapeutic targets. In this study, we analyzed the immune cell infiltration in BTC and developed a promising immune signature score to predict prognosis in BTC. Immunohistochemistry (IHC) was carried out on tissue microarray sections from 45 patients with resectable cholangiocarcinoma for the detection of 6-sulfoLacNAc+ monocytes (slanMo), BDCA-2+ plasmacytoid dendritic cells (pDC), CD8+ or CD4+T-lymphocytes, CD103+ cells, GATA3+ cells, Toll-like receptor (TLR) 3, 7 and 9-expressing cells as well as programmed cell death protein 1 and programmed cell death ligand 1 positive cells. Data from the IHC staining were analyzed and correlated with clinicopathological and survival data. High expression of TLR7, TLR9, and GATA3 was associated with improved overall survival (OS, Log-rank p < 0.05). In addition, TLR9 was associated with better disease-free survival (Log-rank p < 0.05). In the multivariate Cox proportional-hazards model for OS, the TLR/TLR9/GATA3 score was found to be an independent prognostic factor for OS ("Score 2" vs. "Score 0": HR 11.17 95% CI 2.27-54.95, p < 0.01).

Alpha-Fetoprotein- and CD40Ligand-Expressing Dendritic Cells for Immunotherapy of Hepatocellular Carcinoma.

Dendritic cells (DC) as professional antigen presenting cells are able to prime T-cells against the tumor-associated antigen α-fetoprotein (AFP) for immunotherapy of hepatocellular carcinoma (HCC). However, a strong immunosuppressive tumor environment limits their efficacy in patients. The co-stimulation with CD40Ligand (CD40L) is critical in the maturation of DC and T-cell priming. In this study, the impact of intratumoral (i.t.) CD40L-expressing DC to improve vaccination with murine (m)AFP-transduced DC (Ad-mAFP-DC) was analyzed in subcutaneous (s.c.) and orthotopic murine HCC. Murine DC were adenovirally transduced with Ad-mAFP or Ad-CD40L. Hepa129-mAFP-cells were injected into the right flank or the liver of C3H-mice to induce subcutaneous (s.c.) and orthotopic HCC. For treatments, 106 Ad-mAFP-transduced DC were inoculated s.c. followed by 106 CD40L-expressing DC injected intratumorally (i.t.). S.c. inoculation with Ad-mAFP-transduced DC, as vaccine, induced a delay of tumor-growth of AFP-positive HCC compared to controls. When s.c.-inoculation of Ad-mAFP-DC was combined with i.t.-application of Ad-CD40L-DC synergistic antitumoral effects were observed and complete remissions and long-term survival in 62% of tumor-bearing animals were achieved. Analysis of the tumor environment at different time points revealed that s.c.-vaccination with Ad-mAFP-DC seems to stimulate tumor-specific effector cells, allowing an earlier recruitment of effector T-cells and a Th1 shift within the tumors. After i.t. co-stimulation with Ad-CD40L-DC, production of Th1-cytokines was strongly increased and accompanied by a robust tumor infiltration of mature DC, activated CD4+-, CD8+-T-cells as well as reduction of regulatory T-cells. Moreover, Ad-CD40L-DC induced tumor cell apoptosis. Intratumoral co-stimulation with CD40L-expressing DC significantly improves vaccination with Ad-mAFP-DC in pre-established HCC in vivo. Combined therapy caused an early and strong Th1-shift in the tumor environment as well as higher tumor apoptosis, leading to synergistic tumor regression of HCC. Thus, CD40L co-stimulation represents a promising tool for improving DC-based immunotherapy of HCC.