Punzi-loss:: a non-differentiable metric approximation for sensitivity optimisation in the search for new particles.

We present the novel implementation of a non-differentiable metric approximation and a corresponding loss-scheduling aimed at the search for new particles of unknown mass in high energy physics experiments. We call the loss-scheduling, based on the minimisation of a figure-of-merit related function typical of particle physics, a Punzi-loss function, and the neural network that utilises this loss function a Punzi-net. We show that the Punzi-net outperforms standard multivariate analysis techniques and generalises well to mass hypotheses for which it was not trained. This is achieved by training a single classifier that provides a coherent and optimal classification of all signal hypotheses over the whole search space. Our result constitutes a complementary approach to fully differentiable analyses in particle physics. We implemented this work using PyTorch and provide users full access to a public repository containing all the codes and a training example.

A simple nomogram for early postoperative risk prediction of clinically relevant pancreatic fistula after pancreatoduodenectomy.

PURPOSE: Postoperative pancreatic fistulae (POPF) present a serious and life-threatening complication after pancreatic head resections (PD). Therefore, reliable risk stratification to identify those at risk is urgently needed. The aim of this study was to identify postoperative laboratory parameters for the prediction of POPF in the early postoperative period. METHODS: One hundred eighty-two patients who underwent PD from 2012 until 2017 were retrospectively analyzed. Multivariate logistic regression was performed using the GLM (general linear model) method for model building. Two nomograms were created based on the GLM models of postoperative day one and postoperative day one to five. A cohort of 48 patients operated between 2018 and 2019 served as internal validation. RESULTS: Clinically relevant pancreatic fistulae (CR-POPF) were present in 16% (n = 29) of patients. Patients with CR-POPF experienced significantly more insufficiencies of gastroenterostomies, delayed gastric emptying, and more extraluminal bleeding than patients without CR-POPF. Multivariate analysis revealed multiple postoperative predictive models, the best one including ASA, main pancreatic duct diameter, operation time, and serum lipase as well as leucocytes on day one. This model was able to predict CR-POPF with an accuracy of 90% and an AUC of 0.903. Two nomograms were created for easier use. CONCLUSION: Clinically relevant fistula can be predicted using simple laboratory and clinical parameters. Not serum amylase, but serum lipase is an independent predictor of CR-POPF. Our simple nomograms may help in the identification of patients for early postoperative interventions.

Robotic versus laparoscopic distal pancreatectomy: multicentre analysis.

BACKGROUND: The role of minimally invasive distal pancreatectomy is still unclear, and whether robotic distal pancreatectomy (RDP) offers benefits over laparoscopic distal pancreatectomy (LDP) is unknown because large multicentre studies are lacking. This study compared perioperative outcomes between RDP and LDP. METHODS: A multicentre international propensity score-matched study included patients who underwent RDP or LDP for any indication in 21 European centres from six countries that performed at least 15 distal pancreatectomies annually (January 2011 to June 2019). Propensity score matching was based on preoperative characteristics in a 1 : 1 ratio. The primary outcome was the major morbidity rate (Clavien-Dindo grade IIIa or above). RESULTS: A total of 1551 patients (407 RDP and 1144 LDP) were included in the study. Some 402 patients who had RDP were matched with 402 who underwent LDP. After matching, there was no difference between RDP and LDP groups in rates of major morbidity (14.2 versus 16.5 per cent respectively; P = 0.378), postoperative pancreatic fistula grade B/C (24.6 versus 26.5 per cent; P = 0.543) or 90-day mortality (0.5 versus 1.3 per cent; P = 0.268). RDP was associated with a longer duration of surgery than LDP (median 285 (i.q.r. 225-350) versus 240 (195-300) min respectively; P < 0.001), lower conversion rate (6.7 versus 15.2 per cent; P < 0.001), higher spleen preservation rate (81.4 versus 62.9 per cent; P = 0.001), longer hospital stay (median 8.5 (i.q.r. 7-12) versus 7 (6-10) days; P < 0.001) and lower readmission rate (11.0 versus 18.2 per cent; P = 0.004). CONCLUSION: The major morbidity rate was comparable between RDP and LDP. RDP was associated with improved rates of conversion, spleen preservation and readmission, to the detriment of longer duration of surgery and hospital stay.

Changes in attentional resources during the acquisition of laparoscopic surgical skills.

BACKGROUND: Increasing familiarity and practice might free up mental resources during laparoscopic surgical skills training. The aim of the study was to track changes in mental resource allocation during acquisition of laparoscopic surgical skills. METHODS: Medical students with no previous experience in laparoscopic surgery took part in a 5-week laparoscopic training curriculum. At the beginning and end of the training period, one of the training tasks was combined with a secondary auditory detection task that required pressing a foot switch for defined target tones, creating a dual-task situation. During execution of the two concurrent tasks, continuous electroencephalographic measurements were made, with special attention to the P300 component, an index of mental resources. Accuracy and reaction times of the secondary task were determined. RESULTS: All 14 participants successfully completed the training curriculum. Target times for successful completion of individual tasks decreased significantly during training sessions (P <0.001 for all tasks). Comparing results before and after training showed a significant decrease in event-related brain potential amplitude at the parietal electrode cluster (P300 component, W = 67, P = 0.026), but there were no differences in accuracy (percentage correct responses: W = 48, P = 0.518) or reaction times (W = 42, P = 0.850) in the auditory detection task. CONCLUSION: The P300 decrease in the secondary task over training demonstrated a shift of mental resources to the primary task: the surgical exercise. This indicates that, with more practice, mental resources are freed up for additional tasks.

Laparoscopic versus open extended radical left pancreatectomy for pancreatic ductal adenocarcinoma: an international propensity-score matched study.

BACKGROUND: A radical left pancreatectomy in patients with pancreatic ductal adenocarcinoma (PDAC) may require extended, multivisceral resections. The role of a laparoscopic approach in extended radical left pancreatectomy (ERLP) is unclear since comparative studies are lacking. The aim of this study was to compare outcomes after laparoscopic vs open ERLP in patients with PDAC. METHODS: An international multicenter propensity-score matched study including patients who underwent either laparoscopic or open ERLP (L-ERLP; O-ERLP) for PDAC was performed (2007-2015). The ISGPS definition for extended resection was used. Primary outcomes were overall survival, margin negative rate (R0), and lymph node retrieval. RESULTS: Between 2007 and 2015, 320 patients underwent ERLP in 34 centers from 12 countries (65 L-ERLP vs. 255 O-ERLP). After propensity-score matching, 44 L-ERLP could be matched to 44 O-ERLP. In the matched cohort, the conversion rate in L-ERLP group was 35%. The L-ERLP R0 resection rate (matched cohort) was comparable to O-ERLP (67% vs 48%; P = 0.063) but the lymph node yield was lower for L-ERLP than O-ERLP (median 11 vs 19, P = 0.023). L-ERLP was associated with less delayed gastric emptying (0% vs 16%, P = 0.006) and shorter hospital stay (median 9 vs 13 days, P = 0.005), as compared to O-ERLP. Outcomes were comparable for additional organ resections, vascular resections (besides splenic vessels), Clavien-Dindo grade ≥ III complications, or 90-day mortality (2% vs 2%, P = 0.973). The median overall survival was comparable between both groups (19 vs 20 months, P = 0.571). Conversion did not worsen outcomes in L-ERLP. CONCLUSION: The laparoscopic approach may be used safely in selected patients requiring ERLP for PDAC, since morbidity, mortality, and overall survival seem comparable, as compared to O-ERLP. L-ERLP is associated with a high conversion rate and reduced lymph node yield but also with less delayed gastric emptying and a shorter hospital stay, as compared to O-ERLP.

Predictors for Survival in an International Cohort of Patients Undergoing Distal Pancreatectomy for Pancreatic Ductal Adenocarcinoma.

BACKGROUND: Surgical factors, including resection of Gerota's fascia, R0-resection, and lymph node yield, may be associated with survival after distal pancreatectomy (DP) for pancreatic ductal adenocarcinoma (PDAC), but evidence from large multicenter studies is lacking. This study aimed to identify predictors for overall survival after DP for PDAC, especially those related to surgical technique. PATIENTS AND METHODS: Data from an international retrospective cohort including patients from 11 European countries and the USA who underwent DP for PDAC (2007-2015) were analyzed. Cox proportional hazard analyses were performed and included Gerota's fascia resection, R0 resection, lymph node ratio, extended resection, and a minimally invasive approach. RESULTS: Overall, 1200 patients from 34 centers with median follow-up of 15 months [interquartile range (IQR) 5-31 months] and median survival period of 30 months [95% confidence interval (CI), 27-33 months] were included. Gerota's fascia resection [hazard ratio (HR) 0.74; p = 0.019], R0 resection (HR 0.70; p = 0.006), and decreased lymph node ratio (HR 0.28; p < 0.001) were associated with improved overall survival, whereas extended resection (HR 1.75; p < 0.001) was associated with worse overall survival. A minimally invasive approach did not improve survival as compared with an open approach (HR 1.14; p = 0.350). Adjuvant chemotherapy (HR 0.67; p = 0.003) was also associated with improved overall survival. CONCLUSIONS: This international cohort identified Gerota's fascia resection, R0 resection, and decreased lymph node ratio as factors associated with improved overall survival during DP for PDAC. Surgeons should strive for R0 resection and adequate lymphadenectomy and could also consider Gerota's fascia resection in their routine surgical approach.

[Gastroenteropancreatic neuroendocrine neoplasms-Heterogeneity, management and perspectives of treatment and research]. / Gastroenteropankreatische neuroendokrine Neoplasien ­ Heterogenität, Management und Perspektiven der Versorgung und Forschung.

The term neuroendocrine neoplasms (NEN) encompasses a molecularly and biologically very heterogeneous group of tumors, which have in common their origin in neuroendocrine cells. The also very heterogeneous subgroup of gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) is the best classified and investigated group. This article provides a systematic review of the current classification, diagnostics and treatment options of GEP-NEN. In order to achieve a better overview, it was consciously decided not to use an approach based on the primary localization. Instead, a thematic organization according to classification, clinical phenotype, diagnostics and treatment was chosen.

Computerized Medical Evidence-Based Decision Assistance System "MEBDAS®" improves in-hospital outcome after pancreatoduodenectomy for pancreatic cancer.

BACKGROUND: Indication for pancreatoduodenectomy for pancreatic cancer can be challenging. Wrong decisions in indication processes lead to significant health impairments. Computerized decision support systems can take over parts of decision-making processes, making them more accurate. MEBDAS® is a decision-supporting software that predicts outcomes of proposed treatments. AIM: to determine the decision concordance between MEBDAS® and multidisciplinary tumour board (MTB) and the impact of MEBDAS® on in-hospital outcome at different indication thresholds. METHODS: 126 patients with pancreatoduodenectomy from a high-volume university hospital were included. Outcome indicators were in-hospital mortality, Comprehensive Complication Index (CCI®), therapy-related loss of "Quality-Adjusted-Life-Day" (QALD-loss) and prognostic gain of treatment-related "Quality-Adjusted-Life-Year" (QALY-gain). RESULTS: The concordance of decisions was 94.4% at the indication threshold of 0. By raising the indication threshold to 1 year, the concordance decreased to 0%, the in-hospital-mortality dropped from 2.52% to 0%, the CCI® decreased from 26.47 to 13.90, the therapy-related QALD-loss declined from 21.53 to 16.22 days and the prognostic QALY-gain increased from 0.374 to 0.906 years. At IT = 0.250 years, the concordance was 61.11% and differences between MTB and MEBDAS®-group were highly significant (p < 0.001) for all outcome parameters: mortality (3.97% vs. 1.30%), CCI® (28.96 vs. 18.29), therapy-related QALD-loss (24.41 vs. 15.19 days) and QALY-gain (0.351 vs. 0.501 years). CONCLUSION: MEBDAS® decisions are superior to those of MTB in terms of in-hospital-outcome. The inclusion of MEBDAS® in decision procedure makes the indication more accurate and reduces morbidity and mortality. In addition, MEBDAS® can increase patients' competence by involving them in decision-making process.

Mortality after liver surgery in Germany.

BACKGROUND: Mortality rates after liver surgery are not well documented in Germany. More than 1000 hospitals offer liver resection, but there is no central regulation of infrastructure requirements or outcome quality. METHODS: Hospital mortality rates after liver resection were analysed using the standardized hospital discharge data (Diagnosis-Related Groups, ICD-10 and German operations and procedure key codes) provided by the Research Data Centre of the Federal Statistical Office and Statistical Offices of the Länder in Wiesbaden, Germany. RESULTS: A total of 110 332 liver procedures carried out between 2010 and 2015 were identified. The overall hospital mortality rate for all resections was 5·8 per cent. The mortality rate among 17 574 major hepatic procedures was 10·4 per cent. Patients who had surgery for colorectal liver metastases (CRLMs) had the lowest mortality rate among those with malignancy (5·5 per cent), followed by patients with gallbladder cancer (7·1 per cent), hepatocellular carcinoma (9·3 per cent) and intrahepatic cholangiocarcinoma (11·0 per cent). Patients with extrahepatic cholangiocarcinoma had the highest mortality rate (14·6 per cent). The mortality rate for extended hepatectomy was 16·2 per cent and the need for a biliodigestive anastomosis increased this to 25·5 per cent. Failure to rescue after complications led to mortality rates of more than 30 per cent in some subgroups. There was a significant volume-outcome relationship for CRLM surgery in very high-volume centres (mean 26-60 major resections for CRLMs per year). The mortality rate was 4·6 per cent in very high-volume centres compared with 7·5 per cent in very low-volume hospitals (odds ratio 0·60, 95 per cent c.i. 0·42 to 0·77; P < 0·001). CONCLUSION: This analysis of outcome data after liver resection in Germany suggests that hospital mortality remains high. There should be more focused research to understand, improve or justify factors leading to this result, and consideration of centralization of liver surgery.

ANTECEDENTES: En Alemania, los datos de mortalidad después de la cirugía no están bien documentados. En más de 1.000 hospitales se realizan resecciones hepáticas, pero no existe una regulación central de los prerrequisitos estructurales necesarios y de la calidad de los resultados. MÉTODOS: Las tasas de mortalidad hospitalaria relacionadas con las resecciones hepáticas se analizaron utilizando los datos estandarizados del alta hospitalaria (Diagnóstico de grupos relacionados, DRG), la clasificación internacional de enfermedades 10 (ICD10) y la clave de procedimientos y operaciones (códigos OPS) proporcionados por el RDC de la Oficina Federal de Estadística y Oficinas de Estadística de Länder en Wiesbaden, Alemania. RESULTADOS: Se identificaron un total de 110.332 procedimientos hepáticos (de 2010 a 2015). La tasa global de mortalidad hospitalaria para todas las resecciones fue del 5,8%. Las resecciones hepáticas mayores (n = 15.333) presentaron una mortalidad del 10,4%. Los pacientes con metástasis hepáticas colorrectales (colorectal liver metastases, CRLM) tuvieron la mortalidad más baja de entre los pacientes con neoplasias malignas (5,5%), seguidos de los pacientes con cáncer de vesícula biliar (7,1%), colangiocarcinoma intrahepático (intrahepatic colangiocarcinoma, iCC) (11,0%) y carcinoma hepatocelular (hepatocellular carcinoma, HCC) (9,3%). Los pacientes con colangiocarcinoma extrahepático (extrahepatic cholangiocarcinoma, eCC) presentaron la mortalidad más alta (14,6%). Las hepatectomías extendidas (16,2%) y la necesidad de una anastomosis biliodigestiva (biliodigestive anastomosis, BDA) aumentaron la mortalidad a un 25,5%. La falta de solución de algunas complicaciones llevó a tasas de mortalidad de más del 30% en algunos subgrupos. Hubo una relación significativa volumen-resultado para las CRLM en centros de alto volumen (25,3 a 59,7 resecciones mayores/año; razón de oportunidades, odds ratio, OR 0,60, i.c. del 95%: 0,42-0,77; P < 0,001), lo que resultó en una disminución en las tasas de mortalidad de 7,5/6,4/7,5/6,5% a 4,6%. CONCLUSIÓN: El análisis de los resultados después de la resección hepática en Alemania muestra una alta mortalidad hospitalaria inesperada. Este análisis indica la necesidad de efectuar una investigación más específica para comprender, mejorar o justificar los factores que determinan estos hallazgos.

Variation in pancreatoduodenectomy as delivered in two national audits.

BACKGROUND: Nationwide audits facilitate quality and outcome assessment of pancreatoduodenectomy. Differences may exist between countries but studies comparing nationwide outcomes of pancreatoduodenectomy based on audits are lacking. This study aimed to compare the German and Dutch audits for external data validation. METHODS: Anonymized data from patients undergoing pancreatoduodenectomy between 2014 and 2016 were extracted from the German Society for General and Visceral Surgery StuDoQ|Pancreas and Dutch Pancreatic Cancer Audit, and compared using descriptive statistics. Univariable and multivariable risk analyses were undertaken. RESULTS: Overall, 4495 patients were included, 2489 in Germany and 2006 in the Netherlands. Adenocarcinoma was a more frequent indication for pancreatoduodenectomy in the Netherlands. German patients had worse ASA fitness grades, but Dutch patients had more pulmonary co-morbidity. Dutch patients underwent more minimally invasive surgery and venous resections, but fewer multivisceral resections. No difference was found in rates of grade B/C postoperative pancreatic fistula, grade C postpancreatectomy haemorrhage and in-hospital mortality. There was more centralization in the Netherlands (1·3 versus 13·3 per cent of pancreatoduodenectomies in very low-volume centres; P < 0·001). In multivariable analysis, both hospital stay (difference 2·49 (95 per cent c.i. 1·18 to 3·80) days) and risk of reoperation (odds ratio (OR) 1·55, 95 per cent c.i. 1·22 to 1·97) were higher in the German audit, whereas risk of postoperative pneumonia (OR 0·57, 0·37 to 0·88) and readmission (OR 0·38, 0·30 to 0·49) were lower. Several baseline and surgical characteristics, including hospital volume, but not country, predicted mortality. CONCLUSION: This comparison of the German and Dutch audits showed variation in case mix, surgical technique and centralization for pancreatoduodenectomy, but no difference in mortality and pancreas-specific complications.

Comparison of conservative versus surgical therapy for acute appendicitis with abscess in five German hospitals.

INTRODUCTION: The aim of this study was to evaluate the effectiveness of initially conservative therapy compared to immediate appendectomy for acute appendicitis with abscess in terms of medical and economic outcomes. METHODS: Of all the patients treated for appendicitis from January 2009 to December 2017 in five German hospitals, 240 were included in the study. Fifty-three patients received conservative (CON) and 195 patients received surgical (SUR) therapy as initial treatment. RESULTS: Length of stay was similar (12.5 days in CON vs. 13.3 days in SUR, p = 0.530). Readmission rate was higher in the conservative group (54.7% vs. 6.2%, p < 0.001). The majority (53.7%) of the 41 operations in CON group were appendectomies (22 procedures), 1 (4.5%) of them was in the first hospital stay because of persisting symptoms, 21 (95.5%) after a recovery interval. Seven (33.3%) of the recovery appendectomies were performed due to persisting or recurrent symptoms and 14 (66.7%) due to the request of patient. Twenty-one patients (39.6%) in the CON group did not need surgery. The rates of complication-related operations per patient (0.04 versus 0.58, p < 0.001), conversions of surgical technique (1.9% vs. 34.9%, p = 0.0287), and extended resections (1.9% vs. 31.3%, p < 0.001) were higher in SUR group. Furthermore, morbidity, hospital costs, and loss in quality of life were significantly higher in the surgical group (17.0% vs. 66.2%, p < 0.001; € 5044 vs. € 8457, p < 0.001, and 4.3 days vs. 7.5 days, p < 0.001, CON vs. SUR). CONCLUSION: Initially, conservative treatment for acute appendicitis with abscess is preferable to immediate surgical treatment in reduction of morbidity, hospital costs, and loss in quality of life.

Proteome Profiling of Primary Pancreatic Ductal Adenocarcinomas Undergoing Additive Chemoradiation Link ALDH1A1 to Early Local Recurrence and Chemoradiation Resistance.

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis with frequent post-surgical local recurrence. The combination of adjuvant chemotherapy with radiotherapy is under consideration to achieve a prolonged progression-free survival (PFS). To date, few studies have determined the proteome profiles associated with response to adjuvant chemoradiation. We herein analyzed the proteomes of primary PDAC tumors subjected to additive chemoradiation after surgical resection and achieving short PFS (median 6 months) versus prolonged PFS (median 28 months). Proteomic analysis revealed the overexpression of Aldehyde Dehydrogenase 1 Family Member A1 (ALDH1A1) and Monoamine Oxidase A (MAOA) in the short PFS cohort, which were corroborated by immunohistochemistry. In vitro, specific inhibition of ALDH1A1 by A37 in combination with gemcitabine, radiation, and chemoradiation lowered cell viability and augmented cell death in MiaPaCa-2 and Panc 05.04 cells. ALDH1A1 silencing in both cell lines dampened cell proliferation, cell metabolism, and colony formation. In MiaPaCa-2 cells, ALDH1A1 silencing sensitized cells towards treatment with gemcitabine, radiation or chemoradiation. In Panc 05.04, increased cell death was observed upon gemcitabine treatment only. These findings are in line with previous studies that have suggested a role of ALDH1A1 chemoradiation resistance, e.g., in esophageal cancer. In summary, we present one of the first proteome studies to investigate the responsiveness of PDAC to chemoradiation and provide further evidence for a role of ALDH1A1 in therapy resistance.

[Quality indicators for pancreatic surgery : Scientific derivation and clinical relevance]. / Qualitätsindikatoren für die Pankreaschirurgie : Wissenschaftliche Herleitung und klinische Relevanz.

Quality indicators are by definition indirect measures of quality. The selection for the field of pancreatic surgery was based on the clinical relevance and controllability, scientific evidence and the practicability of data acquisition. In terms of outcome quality, hospital mortality, the composite endpoint MTL30 (mortality-transfer-length of stay), and major complications (Clavien-Dindo classification grades 3b and 4) were chosen as being essential. With respect to structural quality, the presence of interventional radiology with constant availability was considered essential. To evaluate target values two strategies were used: a systematic literature search and evaluation of the current numbers from the German Society for General and Visceral Surgery (DGAV) StuDoQ|Pancreas registry for the years 2014-2016. The results are presented in the following consensus statement.

Surgical management of complicated rectovaginal fistulas and the role of omentoplasty.

BACKGROUND: Patients with rectovaginal fistulas have a significantly reduced quality of life. Therefore, surgical therapy is often needed even in palliative cases. The aim of the present study was to perform an analysis of the results of the different treatment options available today. METHODS: We performed a retrospective analysis of patients who underwent treatment for rectovaginal fistulas at the Department of Surgery, University of Schleswig-Holstein, Campus Luebeck and the Department of Surgery, WKK Heide, between January 2000 and September 2016. Complication and recurrence rate were retrospectively evaluated. The median follow-up period was 13 months (range 3-36 months). RESULTS: During the observation period, 58 patients underwent surgery (53 curative, 5 palliative) for rectovaginal fistulas. All patients who underwent curative surgery had an omentoplasty, and 39 of 53 (73.6%) patients underwent a resection. Thirty of 39 (77.0%) resections were low anterior resection, while non-continence-preserving resection included subtotal colectomy (n = 5), pelvic exenteration (n = 2), and proctectomy (n = 2). The fistulas were mainly secondary to inflammatory bowel disease (n = 18) or diverticulitis (n = 13), while 19 fistulas were a complication of different cancers or precancerous lesions. The median follow-up time was 13 months (range 6-36). Four patients (6.9%) had fistula recurrence (3 recurrences after low anterior resection, 1 after primary fistula closure). The mortality rate was 6.9% (n = 4). CONCLUSIONS: Non-resecting methods should be used only in uncomplicated fistulas. Rectovaginal fistulas secondary to inflammatory or malignant disease mostly require extensive therapy. Omentoplasty is effective for the treatment of both high and low rectovaginal fistulas.

Is there any role for minimally invasive surgery in NET?

Neuroendocrine tumors (NET) represent the variability of almost benign lesions either secreting hormones occurring as a single lesion up to malignant lesions with metastatic potential. Treatment of NET is usually performed by surgical resection. Due to the rarity of NET, surgical treatment is mainly based on the experience and recommendations of experts and less on the basis of prospective randomized studies. In addition, the development and establishment of new surgical procedures is made more difficult by their rarity. The development of laparoscopic-assisted surgery has significantly improved the treatment of many diseases. Due to the well-known advantages of laparoscopic surgery, this method has also been increasingly used to treat NET. However, due to limited comparative data, the assumed superiority of laparoscopic surgery in the area NET remains often unclear or not yet proven. This review focuses on the present usage of laparoscopic techniques in the area of NET. Relating to the current literature, this review presents the evidence of various laparoscopic procedures for treatment of adrenal, pancreatic and intestine NET as well as extraadrenal pheochromocytoma and neuroendocrine liver metastases. Further, this review focuses on recent new developments of minimally invasive surgery in the area of NET. Here, robotic-assisted surgery and single-port surgery are promising approaches.

[Laparoscopic pancreatic resection]. / Laparoskopische Pankreasresektion.

INTRODUCTION AND PURPOSE: Despite being technically challenging, laparoscopic surgical procedures are increasingly being used also in pancreatic surgery. This review attempts to evaluate these procedures based on the currently available literature against the background of the high mortality of pancreatic surgery observed nationwide and the as yet unclear oncological validation of these procedures. MATERIAL AND METHODS: Recently published retrospective cohort and register trials have evaluated not only perioperative outcome but also long-term survival after laparoscopic pancreatic resection. RESULTS AND CONCLUSION: Laparoscopic interventions are increasingly being used for treatment of malignant tumors of the pancreas. The advantages of laparoscopy, such as less intraoperative blood loss, reduced postoperative pain and a shorter duration of hospital stay, have all been demonstrated in retrospective trials. Equivalent long-term survival after oncological laparoscopic pancreatic surgery compared to open procedures was also observed in these trials; however, mortality even after laparoscopic pancreatic surgery was found to be significantly increased in low-volume centers. Prospective trials are still needed to prove adequate oncological treatment. Laparoskopische Verfahren haben sich in den letzten Jahren in fast allen Bereichen der Chirurgie quasi zum Standard entwickelt und werden von Patienten zunehmend nachgefragt. Die kosmetischen Ergebnisse sind deutlich besser als bei konventionellem Vorgehen und sie reduzieren unter anderem den postoperativen Schmerz, Schmerzmittelbedarf sowie den Krankenhausaufenthalt [29]. Daher ist es wenig überraschend, dass minimal-invasive Verfahren auch bei technisch hochkomplexen Eingriffen, wie z. B. am Pankreas, zunehmend eingesetzt werden. Allerdings wird ihr Einsatz hier noch immer kontrovers diskutiert.

The survival outcome and prognostic factors for distal cholangiocarcinoma following surgical resection: a meta-analysis for the 5-year survival.

PURPOSE: To assess the available evidence on the prognostic factors for the 5-year survival for patients with distal cholangiocarcinoma (DCC) following surgical resection. METHODS: We performed a comprehensive search of abstracts included in databases where relevant studies were published between January 2000 and August 2015. Risk ratios (RRs), 95 % confidence intervals (95 % CIs), and random-effects model were calculated using RevMan 5.3 software. RESULTS: A total of 23 observational studies involving 2063 patients with DCC were analyzed. The meta-analysis showed that postoperative adjuvant chemotherapy was not confirmed as a prognostic factor, with similar 5-year survival rates between those receiving and not receiving chemotherapy (RR 0.71; 95 % CI 0.21-2.36; P = 0.57). Perineural invasion (RR 0.51; 95 % CI 0.40-0.64; P < 0.00001), lymph node metastasis (RR 0.51; 95 % CI 0.38-0.70; P < 0.0001), positive resection margin status (RR 2.11; 95 % CI 1.36-3.30; P = 0.001), and not-well-differentiated adenocarcinoma (RR 1.77; 95 % CI 1.39-2.25; P < 0.00001) were associated with shorter survival. CONCLUSIONS: Perineural invasion, lymph node metastasis, resection margin status, and tumor differentiation were the significant prognostic factors for the 5-year survival.

Predictors of Morbidity and Mortality in Esophageal Perforation: Retrospective Study of 80 Patients.

BACKGROUND AND AIMS: Esophageal perforation is a life-threatening disease. Factors impacting morbidity and mortality include the cause and site of the perforation, the time to diagnosis, and the therapeutic procedure. This study aimed to identify risk factors for morbidity and mortality after esophageal perforation. PATIENTS AND METHODS: This retrospective study analyzed data collected from all patients treated for esophageal perforation at the Department of Surgery, University of Schleswig-Holstein, Luebeck Campus, from January 1986 through December 2011. RESULTS: Altogether, 80 patients (52 men, 28 women; mean age 65 years) were treated. The cause of perforation was intraluminal in 44 (55%) (group A) and extraluminal in 2 (3%) (group B). Spontaneous perforations were observed in 12 (15%) (group C). Perforations were due to a preexisting esophageal disease in 22 (28%) (group D). The survival rate was higher for group A (82%) than for groups B (50%), C (57%), and D (59%). The distal third of the esophagus had the highest prevalence of perforations (49, 61%) independent of the cause. Mortality, however, was independent of the perforation site. Perforations were diagnosed within 24 h in 57% (n = 46) of patients, associated with a statistically significant lower mortality rate (p = 0.035). Altogether, 40 patients underwent non-operative treatment, and among those 27 had endoscopic treatment. Emergency thoracic surgery was performed in 40 patients: direct suture of the defect (n = 26), partial esophageal resection (n = 11), other (n = 3). Significantly higher morbidity (p = 0.007) and prolonged hospitalization (p < 0.0001) was observed among patients who underwent emergency surgery. Mortality was higher in the surgical group (14/40) than in the non-operative treatment group (9/40) but without statistical significance. CONCLUSION: Intraluminal perforations, rapid initiation of therapy, and non-operative treatment were associated with favorable outcomes. The perforation site did not have an impact on outcomes. Esophageal resection was associated with high mortality.