Reconstruction Techniques and Associated Morbidity in Minimally Invasive Gastrectomy for Cancer - Insights from the GastroBenchmark and GASTRODATA databases.

OBJECTIVE/BACKGROUND: Various anastomotic and reconstruction techniques are used for minimally invasive total (miTG) and distal gastrectomy (miDG). Their effects on postoperative morbidity have not been extensively studied. METHODS: MiTG and miDG patients were selected from 9356 oncological gastrectomies performed 2017-2021 in 44 centers. Endpoints included anastomotic leakage (AL) rate and postoperative morbidity tested by multivariable analysis. RESULTS: Three major anastomotic techniques (circular stapled (CS); linear stapled (LS); hand sewn (HS)), and three major bowel reconstruction types (Roux (RX); Billroth I (BI); Billroth II (BII)) were identified in miTG (n=878) and miDG (n=3334). Postoperative complications including AL (5.2% vs. 1.1%), overall (28.7% vs. 16.3%) and major morbidity (15.7% vs. 8.2%), as well as 90-day mortality (1.6% vs. 0.5%) were higher after miTG compared with miDG. After miTG, AL rate was higher after CS (4.3%) and HS (7.9%) compared with LS (3.4%). Similarly, major complications (LS: 9.7%, CS: 16.2%, HS: 12.7%) were lowest after LS. Multivariate analysis confirmed anastomotic technique as predictive factor for AL, overall and major complications. In miDG, AL rate (BI: 1.4%, BII 0.8%, RX 1.2%), overall (BI: 14.5%, BII: 15.0%, RX: 18.7%,) and major morbidity (BI: 7.9%, BII: 9.1%, RX: 7.2%), and mortality (BI: 0%, BII: 0.1%, RY: 1.1%%) were not affected by bowel reconstruction. CONCLUSION: In oncologically suitable situations, miDG should be preferred to miTG, as postoperative morbidity is significantly lower. LS should be a preferred anastomotic technique for miTG in Western Centers. Conversely, bowel reconstruction in DG may be chosen according to surgeon's preference.

Development of predictive model for predicting postoperative BMI and optimize bariatric surgery: a single center pilot study.

BACKGROUND: The pilot study addresses the challenge of predicting postoperative outcomes, particularly body mass index (BMI) trajectories, following bariatric surgery. The complexity of this task makes preoperative personalized obesity treatment challenging. OBJECTIVES: To develop and validate sophisticated machine learning (ML) algorithms capable of accurately forecasting BMI reductions up to 5 years following bariatric surgery aiming to enhance planning and postoperative care. The secondary goal involves the creation of an accessible web-based calculator for healthcare professionals. This is the first article that compares these methods in BMI prediction. SETTING: The study was carried out from January 2012 to December 2021 at GZOAdipositas Surgery Center, Switzerland. Preoperatively, data for 1004 patients were available. Six months postoperatively, data for 1098 patients were available. For the time points 12 months, 18 months, 2 years, 3 years, 4 years, and 5 years the following number of follow-ups were available: 971, 898, 829, 693, 589, and 453. METHODS: We conducted a comprehensive retrospective review of adult patients who underwent bariatric surgery (Roux-en-Y gastric bypass or sleeve gastrectomy), focusing on individuals with preoperative and postoperative data. Patients with certain preoperative conditions and those lacking complete data sets were excluded. Additional exclusion criteria were patients with incomplete data or follow-up, pregnancy during the follow-up period, or preoperative BMI ≤30 kg/m2. RESULTS: This study analyzed 1104 patients, with 883 used for model training and 221 for final evaluation, the study achieved reliable predictive capabilities, as measured by root mean square error (RMSE). The RMSE values for three tasks were 2.17 (predicting next BMI value), 1.71 (predicting BMI at any future time point), and 3.49 (predicting the 5-year postoperative BMI curve). These results were showcased through a web application, enhancing clinical accessibility and decision-making. CONCLUSION: This study highlights the potential of ML to significantly improve bariatric surgical outcomes and overall healthcare efficiency through precise BMI predictions and personalized intervention strategies.

[Can we learn to die?] / Sterben, kann man das lernen?

INTRODUCTION: The topic of death and the dying is a crucial aspect of patient care, especially for individuals with terminal illnesses. However, discussions about death and dying are often avoided during patient interactions. In this article, our aim is to explore the reasons behind our fear of death and dying and to assess the importance of addressing these issues in shaping and cultivating relationships with our patients and in our personal lives. We argue that being open to impermanence is a valuable tool in our work with patients and their families and should be integrated into conversations with them. Furthermore, discussions about death and dying should play a central role in medical and nursing education as well as professional development.

Towards a Standardization of Learning Curve Assessment in Minimally Invasive Liver Surgery.

OBJECTIVE: The aim was to analyze the learning curves of minimal invasive liver surgery(MILS) and propose a standardized reporting. SUMMARY BACKGROUND DATA: MILS offers benefits compared to open resections. For a safe introduction along the learning curve, formal training is recommended. However, definitions of learning curves and methods to assess it lack standardization. METHODS: A systematic review of PubMed, Web of Science, and CENTRAL databases identified studies on learning curves in MILS. The primary outcome was the number needed to overcome the learning curve. Secondary outcomes included endpoints defining learning curves, and characterization of different learning phases(competency, proficiency and mastery). RESULTS: 60 articles with 12'241 patients and 102 learning curve analyses were included. The laparoscopic and robotic approach was evaluated in 71 and 18 analyses and both approaches combined in 13 analyses. Sixty-one analyses (60%) based the learning curve on statistical calculations. The most often used parameters to define learning curves were operative time (n=64), blood loss (n=54), conversion (n=42) and postoperative complications (n=38). Overall competency, proficiency and mastery were reached after 34 (IQR 19-56), 50 (IQR 24-74), 58 (IQR 24-100) procedures respectively. Intraoperative parameters improved earlier (operative time: competency to proficiency to mastery: -13%, 2%; blood loss: competency to proficiency to mastery: -33%, 0%; conversion rate (competency to proficiency to mastery; -21%, -29%), whereas postoperative complications improved later (competency to proficiency to mastery: -25%, -41%). CONCLUSIONS: This review summarizes the highest evidence on learning curves in MILS taking into account different definitions and confounding factors. A standardized three-phase reporting of learning phases (competency, proficiency, mastery) is proposed and should be followed.

Palliative care inpatients in Switzerland (2012-2021): characteristics, in-hospital mortality and avoidable admissions.

OBJECTIVES: Palliative patients generally prefer to be cared for and die at home. Overly aggressive treatments place additional strain on already burdened patients and healthcare services, contributing to decreased quality of life and increased healthcare costs. This study characterises palliative inpatients, quantifies in-hospital mortality and potentially avoidable hospitalisations. METHODS: We conducted a multicentre retrospective analysis using the national inpatient cohort. The extracted data encompassed all inpatients for palliative care spanning the years 2012-2021. The dataset comprised information on demographics, diagnoses, comorbidities, treatments and clinical outcomes. Content experts reviewed a list of treatments for which no hospitalisation was required. RESULTS: 120 396 hospitalisation records indicated palliative patients. Almost half were women (n=59 297, 49%). Most patients were ≥65 years old. 66% had an oncologic primary diagnosis. The majority were admitted from home (82 443; 69%). The patients stayed a median of 12 days (6-20). All treatments for 25 188 patients (21%) could have been performed at home. In-hospital deaths ended 64 739 stays (54%); of note, 10% (n=6357/64 739) of in-hospital deaths occurred within 24 hours. CONCLUSIONS: In this nationwide study of palliative inpatients, two-thirds were 65 years old and older. Regarding the performed treatments alone, a fifth of these hospitalisations can be considered as avoidable. More than half of the patients died during their hospital stay, and 1 in 10 of those within 24 hours.

[Organ donation and organ assessment after primary circulatory death and secondary brain death]. / Organspende und Organassessment nach primärem Herz-Kreislauf-Stillstand und sekundärem Hirntod.

BACKGROUND: The global organ shortage is the biggest obstacle to expand urgently needed liver transplantation activities. In addition to donation after brain death (DBD), donation after primary circulatory death (DCD) has also been introduced in many European countries to increase the number of donated organs. OBJECTIVE: This article summarizes the legal and ethical aspects of DCD, the practical donation process of DCD, the clinical results of DCD liver transplantation with a special focus on organ assessment before a planned DCD liver transplantation. RESULTS: In Europe 11 countries have active DCD liver transplantation programs and a total of 1230 DCD liver transplantations were performed in Europe in 2023. The highest proportion of DCD liver transplantations were recorded in Belgium (52.8%), the Netherlands (42.8%) and Switzerland (32.1%). The adequate selection of donors and recipients is crucial in DCD transplantation and the use of DCD livers particularly depends on the preparedness of the healthcare system for routine machine perfusion. The leaders are Belgium, France and Italy which implant around 68-74% of DCD organs. With an adequate organ assessment, the long-term results of DBD and DCD liver transplantations are comparable. To assess mitochondrial damage and thus organ quality, hypothermic oxygenated machine perfusion (HOPE) was introduced and has the secondary benefit of mitochondrial protection through oxygenation. The establishment of aerobic metabolism in mitochondria under hypothermia leads to a reduction of toxic metabolites and the restoration of ATP storage, which subsequently leads to a reperfusion light during implantation. CONCLUSION: Expanding the donor pool with DCD donors can counteract the global organ shortage. With adequate patient selection and routine organ assessment short-term and also long-term outcomes of DBD and DCD liver transplantation are comparable.

Pancreatic Surgery in Children: Complex, Safe, and Effective.

OBJECTIVE: The aim of this study was to assess indications for and report outcomes of pancreatic surgery in pediatric patients. BACKGROUND: Indications for pancreatic surgery in children are rare and data on surgical outcomes after pediatric pancreatic surgery are scarce. METHODS: All children who underwent pancreatic surgery at a tertiary hospital specializing in pancreatic surgery between 2003 and 2022 were identified from a prospectively maintained database. Indications, surgical procedures, and perioperative as well as long-term outcomes were analyzed. RESULTS: In total, 73 children with a mean age of 12.8 years (range: 4 mo to 18 y) underwent pancreatic surgery during the observation period. Indications included chronic pancreatitis (n=35), pancreatic tumors (n=27), and pancreatic trauma (n=11). Distal pancreatectomy was the most frequently performed procedure (n=23), followed by pancreatoduodenectomy (n=19), duodenum-preserving pancreatic head resection (n=10), segmental pancreatic resection (n=7), total pancreatectomy (n=3), and others (n=11). Postoperative morbidity occurred in 25 patients (34.2%), including 7 cases (9.6%) with major complications (Clavien-Dindo≥III). There was no postoperative (90-d) mortality. The 5-year overall survival was 90.5%. The 5-year event-free survival of patients with chronic pancreatitis was 85.7%, and 69.0% for patients with pancreatic tumors. CONCLUSION: This is the largest single-center study on pediatric pancreatic surgery in a Western population. Pediatric pancreatic surgery can be performed safely. Centralization in pancreatic centers with high expertise in surgery of adult and pediatric patients is important as it both affords the benefits of pancreatic surgery experience and ensures that surgical management is adapted to the specific needs of children.

Assessment of resectability of pancreatic cancer using novel immersive high-performance virtual reality rendering of abdominal computed tomography and magnetic resonance imaging.

PURPOSE: Virtual reality (VR) allows for an immersive and interactive analysis of imaging data such as computed tomography (CT) and magnetic resonance imaging (MRI). The aim of this study is to assess the comprehensibility of VR anatomy and its value in assessing resectability of pancreatic ductal adenocarcinoma (PDAC). METHODS: This study assesses exposure to VR anatomy and evaluates the potential role of VR in assessing resectability of PDAC. Firstly, volumetric abdominal CT and MRI data were displayed in an immersive VR environment. Volunteering physicians were asked to identify anatomical landmarks in VR. In the second stage, experienced clinicians were asked to identify vascular involvement in a total of 12 CT and MRI scans displaying PDAC (2 resectable, 2 borderline resectable, and 2 locally advanced tumours per modality). Results were compared to 2D standard PACS viewing. RESULTS: In VR visualisation of CT and MRI, the abdominal anatomical landmarks were recognised by all participants except the pancreas (30/34) in VR CT and the splenic (31/34) and common hepatic artery (18/34) in VR MRI, respectively. In VR CT, resectable, borderline resectable, and locally advanced PDAC were correctly identified in 22/24, 20/24 and 19/24 scans, respectively. Whereas, in VR MRI, resectable, borderline resectable, and locally advanced PDAC were correctly identified in 19/24, 19/24 and 21/24 scans, respectively. Interobserver agreement as measured by Fleiss κ was 0.7 for CT and 0.4 for MRI, respectively (p < 0.001). Scans were significantly assessed more accurately in VR CT than standard 2D PACS CT, with a median of 5.5 (IQR 4.75-6) and a median of 3 (IQR 2-3) correctly assessed out of 6 scans (p < 0.001). CONCLUSION: VR enhanced visualisation of abdominal CT and MRI scan data provides intuitive handling and understanding of anatomy and might allow for more accurate staging of PDAC and could thus become a valuable adjunct in PDAC resectability assessment in the future.

Enhanced recovery after surgery (ERAS) in colorectal surgery: implementation is still beneficial despite modern surgical and anesthetic care.

PURPOSE: Enhanced recovery after surgery (ERAS) protocols have shown beneficial outcomes in the last 20 years. Nevertheless, simultaneously implemented technical improvements such as minimally invasive access or modified anesthesia care may play a crucial role in optimizing patient outcome. The aim of the study was to investigate the effect of ERAS implementation in a highly specialized colorectal center. METHODS: This is a propensity score matched single-center study comparing the short-term outcomes of patients undergoing elective colorectal surgery in a society-indepedent ERAS program from January 2021 to August 2022 to standard perioperative care from January 2019 to December 2020. RESULTS: Four hundred fifty-six patients were included in the propensity score matched analysis with 228 patients per group (ERAS vs. standard care). Minimally invasive access was used in 80.2% vs. 77.6% (p = 0.88), and there were 16.6% vs. 18.8% (p = 0.92) rectal procedures in the ERAS and standard care group, respectively. Major complications occurred in 10.1% vs. 11.4% (p = 0.65) and anastomotic leakage demanding operative revision in 2.2% vs. 2.6% (p = 0.68) in the ERAS and standard care group, respectively. ERAS lead to a lower number of non-surgical complications compared to standard care (57 vs. 79; p = 0.02). Mean length of stay (LOS) and mean costs per case were lower in ERAS compared to standard care (9.2 ± 5.6 days vs. 12.7 ± 7.4 days, p < 0.01; costs 33,727 ± 15,883 USD vs. 40,309 ± 29,738 USD, p < 0.01). CONCLUSION: The implementation of an ERAS protocol may lead to a reduction of LOS, costs, and a lower number of non-surgical complications even in a highly specialized colorectal unit using modern surgical and anesthetic care. ( ClinialTrials.gov number NCT05773248).

Low serum iPTH at the end of surgery is the earliest predictor of postoperative hypocalcemia after total thyroidectomy.

BACKGROUND: The most frequent complication of total thyroidectomy remains hypocalcemia due to low postoperative levels of serum intact parathyroid hormone (iPTH). The purpose of this study was to investigate the role of decreased iPTH at the end of surgery in predicting hypocalcemia. In addition, we examined the percentage decrease of iPTH as potential indicator of hypocalcemia. METHODS: We retrospectively collected the data of patients who underwent total thyroidectomy for benign and malignant diseases at our institution between 2010 and 2022. The iPTH level was measured before and at the end of surgery, and serum calcium levels on the first postoperative day. Demographic, clinical, and biochemical characteristics of patients with low iPTH were compared with patients with normal iPTH levels using ANOVA for continuous variables and χ2-tests for categorical variables. Multivariable logistic regression analysis evaluated the association of iPTH at the end of surgery and the relative reduction of iPTH with postoperative hypocalcemia. RESULTS: The mean age of the 607 patients in this study was 55.6 years, and the female-to-male ratio was 5:1. Goiter was the most common indication for surgery (N = 382, 62.9%), followed by Graves' disease (N = 135, 22.2%). The mean preoperative iPTH was 49.0 pg/ml, while the mean postoperative iPTH was 29.3 pg/ml. A total of 197 patients (32.5%) had an iPTH level below normal, 77 patients (39%), had iPTH levels of 10-15.0 pg/ml and 120 patients (61%) of < 10.0 pg/ml at the end of surgery. Among all patients, 124 (20.4%) developed hypocalcemia on the first postoperative day. The mean percentage of decrease of iPTH was highest among patients with iPTH < 10 pg/ml (76.9%, p < 0.01); this group of patients had also the highest rate of postoperative hypocalcemia on day one (45.0% vs. 26.0% vs 12.2%, p < 0.01). CONCLUSIONS: Measurement of iPTH at the end of total thyroidectomy predicts patients who are at risk for postoperative hypocalcemia. The combination of low serum iPTH with a decrease in iPTH level of ≥ 50% may improve prediction of hypocalcemia compared to iPTH levels alone allowing for early calcium substitution in these patients at high risk of developing postoperative hypocalcemia.

Reliability of Medical Information Provided by ChatGPT: Assessment Against Clinical Guidelines and Patient Information Quality Instrument.

BACKGROUND: ChatGPT-4 is the latest release of a novel artificial intelligence (AI) chatbot able to answer freely formulated and complex questions. In the near future, ChatGPT could become the new standard for health care professionals and patients to access medical information. However, little is known about the quality of medical information provided by the AI. OBJECTIVE: We aimed to assess the reliability of medical information provided by ChatGPT. METHODS: Medical information provided by ChatGPT-4 on the 5 hepato-pancreatico-biliary (HPB) conditions with the highest global disease burden was measured with the Ensuring Quality Information for Patients (EQIP) tool. The EQIP tool is used to measure the quality of internet-available information and consists of 36 items that are divided into 3 subsections. In addition, 5 guideline recommendations per analyzed condition were rephrased as questions and input to ChatGPT, and agreement between the guidelines and the AI answer was measured by 2 authors independently. All queries were repeated 3 times to measure the internal consistency of ChatGPT. RESULTS: Five conditions were identified (gallstone disease, pancreatitis, liver cirrhosis, pancreatic cancer, and hepatocellular carcinoma). The median EQIP score across all conditions was 16 (IQR 14.5-18) for the total of 36 items. Divided by subsection, median scores for content, identification, and structure data were 10 (IQR 9.5-12.5), 1 (IQR 1-1), and 4 (IQR 4-5), respectively. Agreement between guideline recommendations and answers provided by ChatGPT was 60% (15/25). Interrater agreement as measured by the Fleiss κ was 0.78 (P<.001), indicating substantial agreement. Internal consistency of the answers provided by ChatGPT was 100%. CONCLUSIONS: ChatGPT provides medical information of comparable quality to available static internet information. Although currently of limited quality, large language models could become the future standard for patients and health care professionals to gather medical information.

The Value of Tumour Markers in the Detection of Relapse-Lessons Learned from the Swiss Austrian German Testicular Cancer Cohort Study.

The tumour markers alpha-fetoprotein (AFP), beta human chorionic gonadotropin (ßHCG), and lactate dehydrogenase (LDH) have established roles in the management and follow-up of testicular cancer. While a tumour marker rise can serve as an indicator of relapse, the frequency of false-positive marker events has not been studied systematically in larger cohorts. We assessed the validity of serum tumour markers for the detection of relapse in the Swiss Austrian German Testicular Cancer Cohort Study (SAG TCCS). This registry was set up to answer questions on the diagnostic performance and impact of imaging and laboratory tests in the management of testicular cancer, and has included 948 patients between January 2014 and July 2021.A total of 793 patients with a median follow-up of 29.0 mo were included. In total, 71 patients (8.9%) had a proven relapse, which was marker positive in 31 patients (43.6%). Of all patients, 124 (15.6%) had an event of a false-positive marker elevation. The positive predictive value (PPV) of the markers was limited, highest for ßHCG (33.8%) and lowest for LDH (9.4%). PPV tended to increase with higher levels of elevation. These findings underline the limited accuracy of the conventional tumour markers to indicate or rule out a relapse. Especially, LDH as part of routine follow-up should be questioned. Patient summary: With the diagnosis of testicular cancer, the three tumour markers alpha-fetoprotein, beta human chorionic gonadotropin, and lactate dehydrogenase are routinely measured during follow-up to monitor for relapse. We demonstrate that these markers are often falsely elevated, and, by contrast, many patients do not have marker elevations despite a relapse. The results of this study can lead to improved use of these tumour markers during follow-up of testis cancer patients.

Body and mind? Exploring physiological and psychological factors to explain endurance performance in cycling.

Endurance athletes attribute performance not only to physiological factors, but also refer to psychological factors such as motivation. The goal of this study was to quantify the proportion of the variance in endurance performance that is explained by psychological factors in addition to the physiological factor VO2max. Twenty-five athletes of the U17 Swiss Cycling national team (7f, 18 m, 15.3 ± 0.5 years) were examined in a cross-sectional study with psychological factors and VO2max as independent variables and endurance performance in road cycling as dependent variable. Questionnaires were used to assess psychological factors (i.e. use of mental techniques, self-compassion, mental toughness, achievement motivation, and action vs. state orientation). VO2max was measured by a step incremental cycle ergometer test of exhaustion. Endurance performance was measured in a cycling mountain time trial (1,320 m long, incline of 546 meters). A multiple regression model was created by using forward selection of regression model predictors. Results showed that higher VO2max values (ß = .48), being male (ß = .26), and higher achievement motivation (i.e. perseverance, ß = .11) were associated with a better endurance performance. A more frequent use of one particular mental technique (i.e. relaxation techniques, ß = .03) was associated with a worse endurance performance. Our study shows that a physiological factor like VO2max explains endurance performance to a large extent but psychological factors account for additional variance. In particular, one aspect of achievement motivation, namely perseverance, was associated with a better endurance performance. HIGHLIGHTSEndurance performance is explained by physiological (e.g. VO2max) and psychological (e.g. perseverance) factorsVO2max explains young cyclists' endurance performance to a large extentPerseverance explained performance beyond the influence of VO2max.

Canakinumab in patients with COVID-19 and type 2 diabetes - A multicentre, randomised, double-blind, placebo-controlled trial.

Background: Patients with type 2 diabetes and obesity have chronic activation of the innate immune system possibly contributing to the higher risk of hyperinflammatory response to SARS-CoV2 and severe COVID-19 observed in this population. We tested whether interleukin-1ß (IL-1ß) blockade using canakinumab improves clinical outcome. Methods: CanCovDia was a multicenter, randomised, double-blind, placebo-controlled trial to assess the efficacy of canakinumab plus standard-of-care compared with placebo plus standard-of-care in patients with type 2 diabetes and a BMI > 25 kg/m2 hospitalised with SARS-CoV2 infection in seven tertiary-hospitals in Switzerland. Patients were randomly assigned 1:1 to a single intravenous dose of canakinumab (body weight adapted dose of 450-750 mg) or placebo. Canakinumab and placebo were compared based on an unmatched win-ratio approach based on length of survival, ventilation, ICU stay and hospitalization at day 29. This study is registered with ClinicalTrials.gov, NCT04510493. Findings: Between October 17, 2020, and May 12, 2021, 116 patients were randomly assigned with 58 in each group. One participant dropped out in each group for the primary analysis. At the time of randomization, 85 patients (74·6 %) were treated with dexamethasone. The win-ratio of canakinumab vs placebo was 1·08 (95 % CI 0·69-1·69; p = 0·72). During four weeks, in the canakinumab vs placebo group 4 (7·0%) vs 7 (12·3%) participants died, 11 (20·0 %) vs 16 (28·1%) patients were on ICU, 12 (23·5 %) vs 11 (21·6%) were hospitalised for more than 3 weeks, respectively. Median ventilation time at four weeks in the canakinumab vs placebo group was 10 [IQR 6.0, 16.5] and 16 days [IQR 14.0, 23.0], respectively. There was no statistically significant difference in HbA1c after four weeks despite a lower number of anti-diabetes drug administered in patients treated with canakinumab. Finally, high-sensitive CRP and IL-6 was lowered by canakinumab. Serious adverse events were reported in 13 patients (11·4%) in each group. Interpretation: In patients with type 2 diabetes who were hospitalised with COVID-19, treatment with canakinumab in addition to standard-of-care did not result in a statistically significant improvement of the primary composite outcome. Patients treated with canakinumab required significantly less anti-diabetes drugs to achieve similar glycaemic control. Canakinumab was associated with a prolonged reduction of systemic inflammation. Funding: Swiss National Science Foundation grant #198415 and University of Basel. Novartis supplied study medication.

Robust hand tracking for surgical telestration.

PURPOSE: As human failure has been shown to be one primary cause for post-operative death, surgical training is of the utmost socioeconomic importance. In this context, the concept of surgical telestration has been introduced to enable experienced surgeons to efficiently and effectively mentor trainees in an intuitive way. While previous approaches to telestration have concentrated on overlaying drawings on surgical videos, we explore the augmented reality (AR) visualization of surgical hands to imitate the direct interaction with the situs. METHODS: We present a real-time hand tracking pipeline specifically designed for the application of surgical telestration. It comprises three modules, dedicated to (1) the coarse localization of the expert's hand and the subsequent (2) segmentation of the hand for AR visualization in the field of view of the trainee and (3) regression of keypoints making up the hand's skeleton. The semantic representation is obtained to offer the ability for structured reporting of the motions performed as part of the teaching. RESULTS: According to a comprehensive validation based on a large data set comprising more than 14,000 annotated images with varying application-relevant conditions, our algorithm enables real-time hand tracking and is sufficiently accurate for the task of surgical telestration. In a retrospective validation study, a mean detection accuracy of 98%, a mean keypoint regression accuracy of 10.0 px and a mean Dice Similarity Coefficient of 0.95 were achieved. In a prospective validation study, it showed uncompromised performance when the sensor, operator or gesture varied. CONCLUSION: Due to its high accuracy and fast inference time, our neural network-based approach to hand tracking is well suited for an AR approach to surgical telestration. Future work should be directed to evaluating the clinical value of the approach.

Metastatic Potential of Small Testicular Germ Cell Tumors: Implications for Surveillance of Small Testicular Masses.

Incidental detection of urogenital tumors has increased in recent decades owing to the greater use of ultrasonography and cross-sectional imaging. For patients with low-risk prostate cancer or small renal masses, active surveillance represents a valid treatment option. Similarly, for men with small testicular masses <10 mm, active surveillance has been discussed as an alternative to surgery, although little is known regarding the behavior of small testicular germ cell tumors (GCTs). In the Swiss Austrian German Testicular Cancer Cohort Study we identified 849 patients (546 seminoma, 303 nonseminoma) treated with radical inguinal orchiectomy for GCT with a median tumor diameter of 35 mm. A tumor diameter <10 mm was observed in 25 patients (13 seminoma, 12 nonseminoma). Of these, five patients (20%) presented with primary metastatic disease, all of whom had elevated tumor markers and nonseminomatous GCTs. Two patients (8%) with initially localized disease (1 seminoma, 1 nonseminoma) and without elevated tumor markers experienced relapse at 4 mo (nonseminoma) and 14 mo (seminoma) after orchiectomy, despite the fact that the latter had received adjuvant chemotherapy. These findings highlight the metastatic potential of small testicular GCTs and raise the question of whether active surveillance for small testicular masses is safe. Patient summary: This study on testicular cancer assesses the metastatic potential of small testicular germ cell tumors. Men with small testicular masses should be counseled about the malignant potential of small testicular germ cell tumors.

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

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