Development of an image-based Random Forest classifier for prediction of surgery duration of laparoscopic sigmoid resections.

PURPOSE: Sigmoid diverticulitis is a disease with a high socioeconomic burden, accounting for a high number of left-sided colonic resections worldwide. Modern surgical scheduling relies on accurate prediction of operation times to enhance patient care and optimize healthcare resources. This study aims to develop a predictive model for surgery duration in laparoscopic sigmoid resections, based on preoperative CT biometric and demographic patient data. METHODS: This retrospective single-center cohort study included 85 patients who underwent laparoscopic sigmoid resection for diverticular disease. Potentially relevant procedure-specific anatomical parameters recommended by a surgical expert were measured in preoperative CT imaging. After random split into training and test set (75% / 25%) multiclass logistic regression was performed and a Random Forest classifier was trained on CT imaging parameters, patient age, and sex in the training cohort to predict categorized surgery duration. The models were evaluated in the test cohort using established performance metrics including receiver operating characteristics area under the curve (AUROC). RESULTS: The Random Forest model achieved a good average AUROC of 0.78. It allowed a very good prediction of long (AUROC = 0.89; specificity 0.71; sensitivity 1.0) and short (AUROC = 0.81; specificity 0.77; sensitivity 0.56) procedures. It clearly outperformed the multiclass logistic regression model (AUROC: average = 0.33; short = 0.31; long = 0.22). CONCLUSION: A Random Forest classifier trained on demographic and CT imaging biometric patient data could predict procedure duration outliers of laparoscopic sigmoid resections. Pending validation in a multicenter study, this approach could potentially improve procedure scheduling in visceral surgery and be scaled to other procedures.

Demographic overview of pilonidal sinus carcinoma: updated insights into the incidence.

PURPOSE: There are only rough estimates of the worldwide incidence of pilonidal sinus carcinoma. The purpose of the study is to explore the demographic characteristics of this disease and to provide more precise information about its incidence. METHODS: The study included questioning the surgeons and pathologists in Germany in addition to a literature research. The literature investigation included all published articles about pilonidal carcinoma in all languages. The questionnaire included 1050 pathologists and all 834 hospitals with a surgical division in Germany. The outcome measures included the total number of cases, the language of publication, gender, age, country of origin, interval until the diagnosis of carcinoma, and reported incidence based on local studies. RESULTS: From 1900 to 2022, we found 140 cases of pilonidal sinus carcinoma in 103 articles. The investigation revealed two additional unpublished cases from Germany. The male-to-female ratio was 7.75:1. The countries with the most cases were the USA (35 cases, 25.0%), Spain (13 cases, 9.3%), and Turkey (11 cases, 7.6%). The average age was 54.0 ± 11.8 years and the interval between the diagnosis of the disease and the development of carcinoma was 20.1 ± 14.1 years. There was a parallel increase in reported cases of pilonidal sinus disease and pilonidal carcinoma over the last century. The reported incidence varied from 0.03% to 5.56%. The worldwide calculated incidence equaled 0.17%. CONCLUSION: Due to underreporting and other causes, the incidence of carcinoma emerging on the background of pilonidal sinus disease is higher than reported.

The impact of prior endoscopic or surgical therapy on open Zenker's diverticulum surgery: analysis on a large single center cohort : Comparison of primary and revisional open surgery for Zenker's diverticulum.

BACKGROUND: Endoscopic treatment of Zenker's diverticulum is an attractive minimally invasive alternative compared to the classic open approach. However, increased recurrence rate were reported. In case of relapse, endoscopic therapy might be repeated, or alternatively open surgery is performed. This study aimed to identify potential differences in the outcomes between primary or secondary surgical treatment in Zenker's diverticulum. METHODS: From January 2003 to April 2019, 227 subsequent patients underwent surgical diverticulectomy and cervical myotomy at the surgical department of TUM. 41 of 227 patients had received previous therapy, either open or endoscopic. Perioperative parameters in priorly untreated patients were retrospectively compared to those after previous therapy (mostly endoscopic) with special regard to perioperative data and postoperative complications. Univariate and multivariate regression analyses were performed to identify predictors for postoperative complications. RESULTS: We could show that the number of complications (p = 0.047) in pretreated patients is significant higher as well as the severity after Clavien-Dindo (p = 0.025). Stapler line leakage, wound infections, and operative revision rate was higher also pretreated group. Pretreatment and surgery time showed a significant association with postoperative complications in univariate analysis. In multivariate analysis, pretreatment remained a significant independent predictor of complications. CONCLUSION: The present data indicate that endoscopic therapy might represent a risk factor for postoperative complications in case of relapse surgery. Therefore primary open surgery should be debated in patients with an increased high risk of relapse.

A nationwide population-based study on the clinical and economic burden of anastomotic leakage in colorectal surgery.

AIM: Anastomotic leakage (AL) is one of the most dreaded complications in colorectal surgery. In 2013, the International Classification of Diseases code K91.83 for AL was introduced in Germany, allowing nationwide analysis of AL rates and associated parameters. The aim of this population-based study was to investigate the current incidence, risk factors, mortality, clinical management, and associated costs of AL in colorectal surgery. METHODS: A data query was performed based on diagnosis-related group data of all hospital cases of inpatients undergoing colon or sphincter-preserving rectal resections between 2013 and 2018 in Germany. RESULTS: A total number of 690,690 inpatient cases were included in this study. AL rates were 6.7% for colon resections and 9.2% for rectal resections in 2018. Regarding the treatment of AL, the application of endoluminal vacuum therapy increased during the studied period, while rates of relaparotomy, abdominal vacuum therapy, and terminal enterostomy remained stable. AL was associated with significantly increased in-house mortality (7.11% vs. 20.11% for colon resections and 3.52% vs. 11.33% for rectal resections in 2018) and higher socioeconomic costs (mean hospital reimbursement volume per case: 14,877€ (no AL) vs. 37,521€ (AL) for colon resections and 14,602€ (no AL) vs. 30,606€ (AL) for rectal resections in 2018). CONCLUSIONS: During the studied time period, AL rates did not decrease, and associated mortality remained at a high level. Our study provides updated population-based data on the clinical and economic burden of AL in Germany. Focused research in the field of AL is still urgently necessary to develop targeted strategies to prevent AL, improve patient care, and decrease socioeconomic costs.

pT3 colorectal cancer revisited: a multicentric study on the histological depth of invasion in more than 1000 pT3 carcinomas-proposal for a new pT3a/pT3b subclassification.

BACKGROUND: Pathological TNM staging (pTNM) is the strongest prognosticator in colorectal carcinoma (CRC) and the foundation of its post-operative clinical management. Tumours that invade pericolic/perirectal adipose tissue generally fall into the pT3 category without further subdivision. METHODS: The histological depth of invasion into the pericolic/perirectal fat was digitally and conventionally measured in a training cohort of 950 CRCs (Munich). We biostatistically calculated the optimal cut-off to stratify pT3 CRCs into novel pT3a (≤3 mm)/pT3b (>3 mm) subgroups, which were then validated in two independent cohorts (447 CRCs, Bayreuth/542 CRCs, Mainz). RESULTS: Compared to pT3a tumours, pT3b CRCs showed significantly worse disease-specific survival, including in pN0 vs pN+ and colonic vs. rectal cancers (DSS: P < 0.001, respectively, pooled analysis of all cohorts). Furthermore, the pT3a/pT3b subclassification remained an independent predictor of survival in multivariate analyses (e.g. DSS: P < 0.001, hazard ratio: 4.41 for pT3b, pooled analysis of all cohorts). While pT2/pT3a CRCs showed similar survival characteristics, pT3b cancers remained a distinct subgroup with dismal survival. DISCUSSION: The delineation of pT3a/pT3b subcategories of CRC based on the histological depth of adipose tissue invasion adds valuable prognostic information to the current pT3 classification and implementation into current staging practices of CRC should be considered.

PLAFOKON: a new concept for a patient-individual and intervention-specific flexible surgical platform.

BACKGROUND: Research in the field of surgery is mainly driven by aiming for trauma reduction as well as for personalized treatment concepts. Beyond laparoscopy, other proposed approaches for further reduction of the therapeutic trauma have failed to achieve clinical translation, with few notable exceptions. We believe that this is mainly due to a lack of flexibility and high associated costs. We aimed at addressing these issues by developing a novel minimally invasive operating platform and a preoperative design workflow for patient-individual adaptation and cost-effective rapid manufacturing of surgical manipulators. In this article, we report on the first in-vitro cholecystectomy performed with our operating platform. METHODS: The single-port overtube (SPOT) is a snake-like surgical manipulator for minimally invasive interventions. The system layout is highly flexible and can be adapted in design and dimensions for different kinds of surgery, based on patient- and disease-specific parameters. For collecting and analyzing this data, we developed a graphical user interface, which assists clinicians during the preoperative planning phase. Other major components of our operating platform include an instrument management system and a non-sterile user interface. For the trial surgery, we used a validated phantom which was further equipped with a porcine liver including the gallbladder. RESULTS: Following our envisioned preoperative design workflow, a suitable geometry of the surgical manipulator was determined for our trial surgery and rapidly manufactured by means of 3D printing. With this setup, we successfully performed a first in-vitro cholecystectomy, which was completed in 78 min. CONCLUSIONS: By conducting the trial surgery, we demonstrated the effectiveness of our PLAFOKON operating platform. While some aspects - especially regarding usability and ergonomics - can be further optimized, the overall performance of the system is highly promising, with sufficient flexibility and strength for conducting the necessary tissue manipulations.

Surgomics: personalized prediction of morbidity, mortality and long-term outcome in surgery using machine learning on multimodal data.

BACKGROUND: Personalized medicine requires the integration and analysis of vast amounts of patient data to realize individualized care. With Surgomics, we aim to facilitate personalized therapy recommendations in surgery by integration of intraoperative surgical data and their analysis with machine learning methods to leverage the potential of this data in analogy to Radiomics and Genomics. METHODS: We defined Surgomics as the entirety of surgomic features that are process characteristics of a surgical procedure automatically derived from multimodal intraoperative data to quantify processes in the operating room. In a multidisciplinary team we discussed potential data sources like endoscopic videos, vital sign monitoring, medical devices and instruments and respective surgomic features. Subsequently, an online questionnaire was sent to experts from surgery and (computer) science at multiple centers for rating the features' clinical relevance and technical feasibility. RESULTS: In total, 52 surgomic features were identified and assigned to eight feature categories. Based on the expert survey (n = 66 participants) the feature category with the highest clinical relevance as rated by surgeons was "surgical skill and quality of performance" for morbidity and mortality (9.0 ± 1.3 on a numerical rating scale from 1 to 10) as well as for long-term (oncological) outcome (8.2 ± 1.8). The feature category with the highest feasibility to be automatically extracted as rated by (computer) scientists was "Instrument" (8.5 ± 1.7). Among the surgomic features ranked as most relevant in their respective category were "intraoperative adverse events", "action performed with instruments", "vital sign monitoring", and "difficulty of surgery". CONCLUSION: Surgomics is a promising concept for the analysis of intraoperative data. Surgomics may be used together with preoperative features from clinical data and Radiomics to predict postoperative morbidity, mortality and long-term outcome, as well as to provide tailored feedback for surgeons.

Robotic Endoscope Control - State of the Art of Voice Control and Other Options for Laparoscopic Camera Robot Guidance.

In video-based surgery (VBS), the surgeon is no longer the master of his or her view. Visualization of the surgical field is mediated by a video camera guided by an assistant. The separation of visualization and surgical activities leads to significant drawbacks. Early in the history of VBS, active camera holders controlled directly by the surgeon were introduced to replace the human camera assistant. However, despite remarkable technological advances over the past 25 years, robotic camera guidance systems (RCGS) still play only a marginal role. This is less due to inadequate mechanical designs or kinematics, and mainly due to inadequate human-machine interaction. In most cases, a simple task-shift is required that increases the surgeon's mental workload instead of reducing it. The current state of the art in robotic camera guidance, as represented by the SOLOASSIST II RCGS (AKTORmed, Neutraubling, Germany), includes a sophisticated combination of direct manual control, joystick navigation and high-quality voice control that provides the most intuitive surgeon-machine interaction currently available. An in-depth analysis of further clinical needs and promising developments in operating room integration suggests that the addition of context sensitivity could actually enhance the assistive effect of RCGS, making them potentially superior to the average human camera guidance.

Loss of CDX2 in colorectal cancer is associated with histopathologic subtypes and microsatellite instability but is prognostically inferior to hematoxylin-eosin-based morphologic parameters from the WHO classification.

BACKGROUND: Immunohistochemical loss of CDX2 has been proposed as a biomarker of dismal survival in colorectal carcinoma (CRC), especially in UICC Stage II/III. However, it remains unclear, how CDX2 expression is related to central hematoxylin-eosin (HE)-based morphologic parameters defined by 2019 WHO classification and how its prognostic relevance is compared to these parameters. METHODS: We evaluated CDX2 expression in 1003 CRCs and explored its prognostic relevance compared to CRC subtypes, tumour budding and WHO grade in the overall cohort and in specific subgroups. RESULTS: CDX2-low/absent CRCs were enriched in specific morphologic subtypes, right-sided and microsatellite-instable (MSI-H) CRCs (P < 0.001) and showed worse survival characteristics in the overall cohort/UICC Stage II/III (e.g. DFS: P = 0.005) and in microsatellite stable and left-sided CRCs, but not in MSI-H or right-sided CRCs. Compared with CDX2, all HE-based markers showed a significantly better prognostic discrimination in all scenarios. In multivariate analyses including all morphologic parameters, CDX2 was not an independent prognostic factor. CONCLUSION: CDX2 loss has some prognostic impact in univariate analyses, but its prognostic relevance is considerably lower compared to central HE-based morphologic parameters defined by the WHO classification and vanishes in multivariate analyses incorporating these factors.

Retrospective study of prognosis of patients with multiple colorectal carcinomas: synchronous versus metachronous makes the difference.

PURPOSE: Little is known about difference between synchronous colorectal cancer (SCRC) and metachronous colorectal cancer (MCRC) despite the relevance for this selected patient group. The aim of this retrospective review was to analyze patients with SCRC and MCRC. METHODS: All patients who underwent surgery for SCRC and MCRC between 1982 and 2019 were included in this retrospective analysis of our tertiary referral center. Clinical, histological, and molecular genetic characteristics were analyzed. The primary endpoint was cause-specific survival, evaluated by the Kaplan-Meier method. Secondary endpoints were recurrence-free survival and the identification of prognostic factors. RESULTS: Overall, 3714 patients were included in this analysis. Of those, 3506 (94.4%) had a primary unifocal colorectal cancer (PCRC), 103 (2.7%) had SCRC, and 105 (2.8%) had MCRC. SCRC occurred more frequently in elderly (p=0.009) and in male patients (p=0.027). There were no differences concerning tumor stages or grading. Patients with SCRC did not show altered recurrence or survival rates, as compared to unifocal tumors. However, MCRC had a lower rate of recurrence, compared to PCRC (24% vs. 41%, p=0.002) and a lower rate of cause-specific death (13% vs. 37%, p<0.001). Five-year cause-specific survival rates were 63±1% for PCRC, 62±6% for SCRC (p=0.588), and 88±4% for MCRC (p<0.001). Multivariable analysis revealed that MCRC were an independent favorable prognostic parameter regarding case-specific survival. CONCLUSION: Patients with SCRC seem to not have a worse prognosis compared to patients with PCRC. Noteworthy, patients with MCRC showed better survival rates in this retrospective analysis.

Crohn's disease: a population-based study of surgery in the age of biological therapy.

PURPOSE: Despite primary conservative therapy for Crohn's disease, a considerable proportion of patients ultimately needs to undergo surgery. Presumably, due to the increased use of biologics, the number of surgeries might have decreased. This study aimed to delineate current case numbers and trends in surgery in the era of biological therapy for Crohn's disease. METHODS: Nationwide standardized hospital discharge data (diagnosis-related groups statistics) from 2010 to 2017 were used. All patients who were admitted as inpatient Crohn's disease cases in Germany were included. Time-related development of admission numbers, rate of surgery, morbidity, and mortality of inpatient Crohn's disease cases were analyzed. RESULTS: A total number of 201,165 Crohn's disease cases were included. Within the analyzed time period, the total number of hospital admissions increased by 10.6% (n = 23,301 vs. 26,069). While gender and age distribution remained comparable, patients with comorbidities such as stenosis formation (2010: 10.1%, 2017: 13.4%) or malnutrition (2010: 0.8%, 2017: 3.2%) were increasingly admitted. The total number of all analyzed operations for Crohn's disease increased by 7.5% (2010: n = 1567; 2017: n = 1694). On average, 6.8 ± 0.2% of all inpatient patients received ileocolonic resections. Procedures have increasingly been performed minimally invasive (2010: n = 353; 2017: n = 687). The number of postoperative complications remained low. CONCLUSION: Despite the development of novel immunotherapeutics, the number of patients requiring surgery for Crohn's disease remains stable. Interestingly, patients have been increasingly hospitalized with stenosis and malnutrition. The trend towards more minimally invasive operations has not relevantly changed the rate of overall complications.

Innovative approaches for induction of gastrointestinal anastomotic healing: an update on experimental and clinical aspects.

PURPOSE: In most cases, traditional techniques to perform an anastomosis following gastrointestinal resections lead to successful healing. However, despite focused research in the field, in certain high-risk situations leakage rates remain almost unchanged. Here, additional techniques may help the surgeon to protect the anastomosis and prevent leakage. We give an overview of some of the latest developments on experimental and clinical techniques for induction of anastomotic healing. METHODS: We performed a review of the current literature on approaches to improve anastomotic healing. RESULTS: Many promising approaches with a high clinical potential are in the developmental pipeline. Highly experimental approaches like inhibition of matrix metalloproteinases, stem cell therapy, hyperbaric oxygen therapy, induction of the hypoxic adaptive response, and the administration of growth factors are still in the preclinical phase. Other more clinical developments aim to strengthen the anastomotic suture line mechanically while shielding it from the influence of the microbiome. Among them are gluing, seaming the staple line, attachment of laminar biomaterials, and temporary intraluminal tubes. In addition, individualized bowel preparation, selectively reducing certain detrimental microbial populations could become the next stage of bowel preparation. Compression anastomoses are evolving as an equivalent technique additional to established hand-sewn and stapled anastomoses. Fluorescence angiography and flexible endoscopy could complement intraoperative quality control additionally to the air leak tests. Virtual ileostomy is a concept to prepare the bowel for the easy formation of a stoma in case of leakage. CONCLUSION: A variety of promising diagnostic and prophylactic measures that may support the surgeon in identifying high-risk anastomoses and support them according to their potential deficits is currently in development.

Radiologic predictors for failure of non-operative management of complicated diverticulitis: a single-centre cohort study.

PURPOSE: Modern non-operative management of diverticulitis consists of a complex therapeutic regimen and is successful in most cases even of complicated diverticulitis. Still, a certain proportion of patients requires urgent surgery due to failure of the conservative approach. This study aims to identify predictors for failure of conservative treatment of complicated diverticulitis with the need for subsequent urgent resection during the acute episode. METHODS: A single-centre retrospective cohort study was performed at our tertiary centre including cases of acute complicated diverticulitis (characterized by localized abscess formation and/or pericolic air) between 2007 and 2019 that were treated guideline-conform by multimodal conservative treatment. Radiologic characteristics of disease in CT scans upon admission were analysed by uni- and multivariable logistic regression to determine predictors for resection within 30 days after onset of the conservative therapy approach. RESULTS: A total of 669 cases of acute diverticulitis were identified, of which 141 patients met the inclusion criteria. Overall, 13% (n = 19) of patients were operated within 30 days despite initial conservative management. Multivariable logistic regression identified length of inflamed bowel greater than 7 cm (p < 0.011) and abscess formations >1 cm (p < 0.001) as significant risk factors for failure of conservative treatment. CONCLUSION: Patients with length of inflamed bowel >7 cm or abscess formation >1 cm have increased risk for failure of conservative treatment of acute episodes of diverticulitis with contained perforations with subsequent need for urgent surgery. Therefore, conservative treatment of those patients should be monitored with special caution.

New Method for Surgical Diagnostics - a Robotic Telemedical Approach.

Apart from the tremendous increase in the demand for telemedicine during the COVID-19 pandemic, the use of telemedical technology offers many advantages, such as better coverage of rural areas and improved access to specialists. While current telediagnostic possibilities are often limited to a verbal consultation, the field of surgery has already made use of robotics for one of the most challenging areas of medicine: invasive procedures. Since comprehensive diagnostics are a prerequisite for each surgery, we built upon the knowledge gained in telesurgery and developed a telediagnostic system that allows for an extensive perioperative and emergency examination. It is based on a robotic platform consisting of a remote lead robotic arm at the physician's site and a follower robot at the patient's site. Mirroring all movements directly and using force-feedback, both parties can precisely interact, enabling tasks such as auscultation, percussion, and palpation without the need for extensive training. Our overall setup also includes the possibility to measure and monitor all relevant vital parameters and can be used to perform ear and nasopharyngeal inspections as well as an automatic swab to screen for COVID or other contagious diseases prior to hospital admission. In this paper, we focus on the potential of this technology for the surgical community by demonstrating the ease of adding an ultrasound probe to our modular setup to perform a high-quality emergency ultrasound examination. While the system is not yet ready for everyday use in a hospital and drawbacks such as a high cost persist, our setup paves the way for the future use of telediagnostics in surgery.

Annexin A1 Expression Capacity as a Determinant for Disease Severity in Crohn's Disease.

INTRODUCTION: Crohn's disease (CD) is characterized by relapsing intestinal inflammation. The anti-inflammatory protein annexin A1 (ANXA1) has been linked to inflammatory processes in the gut. OBJECTIVE: To examine ANXA1 expression patterns in the inflamed intestine of patients with CD and associate ANXA1 expression capacity with disease characteristics. METHODS: Surgical specimens of patients with CD operated between 2003 and 2015 were examined. Immunohistochemistry and immunofluorescence were performed to delineate ANXA1 expression. Those with pronounced ANXA1 expression were included in further analysis by qPCR. ANXA1 mRNA expression ratio of the inflamed to non-inflamed tissue was determined and defined as expression capacity of the tissue. Depending on their expression capacity, patients were divided into 2 groups (ANXA1-low vs. ANXA1-high), which were associated with clinical characteristics. RESULTS: Immunohistochemical ANXA1 expression was localized in inflamed regions of the intestine. In immunofluorescence, ANXA1 costained with myeloperoxidase as neutrophil marker, CD4 and CD8 as T cell marker but not CD20 as B cell marker or CD68 as macrophage marker. In qPCR, ANXA1 mRNA expression was upregulated by 20-fold in inflamed to noninflamed tissues. Patients with higher intrinsic ANXA1 expression capacity had significantly less severity of inflammation. Furthermore, the ANXA1-high group had significantly more locally restricted disease (p = 0.0070), more stricturating disease (p = 0.0037), and was less frequently treated by preoperative steroid therapy (p = 0.030). CONCLUSIONS: ANXA1 expression was strongly associated with intestinal inflammation and expressed in T cells and neutrophils of the CD tissues. Patients with higher intrinsic ANXA1 expression capacity of the inflamed tissue presented milder inflammatory changes and indolent clinical course.

Machine Learning in the OR: A Collaborative Environment for Surgical Interventions in Visceral Medicine.

Modern surgical methods are becoming increasingly sophisticated and the number of technical devices that are used during these interventions is increasing. However, the surgical operating room (OR) remains a mere conglomerate of unconnected medical devices. The increase in the complexity of device functionality, in addition to the demands of surgery, pushes human mental capacity to its limit. Hence, an "intelligent" collaborative support system would be more than welcome. We envision a "human-like" intelligent system, which could support the surgical team as a situation-aware consultant. This so-called "active collaborative support system" (ACSS) is based on four main pillars: real-time data inflow, a comprehensive knowledge-base, access to the Internet of Things (surgical devices), and an understanding of human language through natural language processing. Recent advances in the area of AI are bringing this ambitious goal within reach, but there is still a considerable amount of work to be done, including the establishment of a new way of thinking in the collaboration between surgeons and computer scientists/engineers, and possibly one day with intelligent machines-provided that AI systems can be sufficiently trusted.

Post-neoadjuvant cellular dissociation grading based on tumour budding and cell nest size is associated with therapy response and survival in oesophageal squamous cell carcinoma.

BACKGROUND: Cellular Dissociation Grade (CDG) composed of tumour budding and cell nest size has been shown to independently predict prognosis in pre-therapeutic biopsies and primary resections of oesophageal squamous cell carcinoma (ESCC). Here, we aimed to evaluate the prognostic impact of CDG in ESCC after neoadjuvant therapy. METHODS: We evaluated cell nest size and tumour budding activity in 122 post-neoadjuvant ESCC resections, correlated the results with tumour regression groups and patient survival and compared the results with data from primary resected cases as well as pre-therapeutic biopsies. RESULTS: CDG remained stable when results from pre-therapeutic biopsies and post-therapeutic resections from the same patient were compared. CDG was associated with therapy response and a strong predictor of overall, disease-specific (DSS) and disease-free (DFS) survival in univariate analysis and-besides metastasis-remained the only significant survival predictor for DSS and DFS in multivariate analysis. Multivariate DFS hazard ratios reached 3.3 for CDG-G2 and 4.9 for CDG-G3 neoplasms compared with CDG-G1 carcinomas (p = 0.016). CONCLUSIONS: CDG is the only morphology-based grading algorithm published to date, which in concert with regression grading, is able to contribute relevant prognostic information in the post-neoadjuvant setting of ESCC.

Automated polyp detection in the colorectum: a prospective study (with videos).

BACKGROUND AND AIMS: Adenoma detection is a highly personalized task that differs markedly among endoscopists. Technical advances are therefore desirable for the improvement of the adenoma detection rate (ADR). An automated computer-driven technology would offer the chance to objectively assess the presence of colorectal polyps during colonoscopy. We present here the application of a real-time automated polyp detection software (APDS) under routine colonoscopy conditions. METHODS: This was a prospective study at a university hospital in Germany. A prototype of a novel APDS ("KoloPol," Fraunhofer IIS, Erlangen, Germany) was used for automated image-based polyp detection. The software functions by highlighting structures of possible polyp lesions in a color-coded manner during real-time colonoscopy procedures. Testing the feasibility of APDS deployment under real-time conditions was the primary goal of the study. APDS polyp detection rates (PDRs) were defined as secondary endpoints provided that endoscopists' detection served as criterion standard. RESULTS: The APDS was applied in 55 routine colonoscopies without the occurrence of any clinically relevant adverse events. Endoscopists' PDRs and ADRs were 56.4% and 30.9%, respectively. The PDRs and ADRs of the APDS were 50.9% and 29.1%, respectively. The APDS detected 55 of 73 polyps (75.3%). Smaller polyp size and flat polyp morphology were correlated with insufficient polyp detection by the APDS. CONCLUSION: Computer-assisted automated low-delay polyp detection is feasible during real-time colonoscopy. Efforts should be undertaken to improve the APDS with respect to smaller and flat shaped polyps. (Clinical trial registration number: NCT02838888.).

Mortality and postoperative complications after different types of surgical reconstruction following pancreaticoduodenectomy-a systematic review with meta-analysis.

BACKGROUND: Pancreaticoduodenectomy/PD is a technically demanding pancreatic resection. Options of surgical reconstruction include (1) the child reconstruction defined as pancreatojejunostomy/PJ followed by hepaticojejunostomy/HJ and the gastrojejunostomy/GJ "the standard/s-Child," (2) the s-child reconstruction with an additional Braun enteroenterostomy "BE-Child," or (3) Isolated-Roux-En-Y-pancreaticojejunostomy "Iso-Roux-En-Y," in which the pancreas anastomosis is reconstructed in a separate loop after the GJ. Yet, the impact of these reconstruction methods on patients' outcome has not been sufficiently compared in a systematic manner. METHODS: A systematic review and meta-analysis were conducted according to the Preferred-Reporting-Items-for-Systematic-review-and-Meta-Analysis/PRISMA-guidelines by screening Pubmed/Medline, Scopus, Cochrane Library and Web-of-Science. Articles meeting predefined criteria were extracted and meta-analysis was performed. RESULTS: Nineteen studies were identified comparing BE-Child or Isolated-Roux-En-Y vs. s-Child. Compared to s-Child neither BE-Child (p = 0.43) nor Iso-Roux-En-Y (p = 0.94) displayed an impact on postoperative mortality, whereas BE-Child showed less postoperative complications (p = 0.02). BE-Child (p = 0.15) and Iso-Roux-En-Y (p = 0.61) did not affect postoperative pancreatic fistula/POPF in general, but BE-Child was associated with a decrease of clinically relevant POPF (p = 0.005), clinically relevant delayed gastric emptying/DGE B/C (p = 0.004), bile leaks (p = 0.01), and hospital stay (p = 0.06). BE-Child entailed also an increased operation time (p = 0.0002) with no impact on DGE A/B/C, hemorrhage, surgical site infections and pulmonary complications. CONCLUSION: BE-Child is associated with a decreased risk for postoperative complications, particularly a decreased risk for clinically relevant DGE, POPF, and bile leaks, whereas Iso-Roux-En-Y does not seem to affect the clinical course after PD. Therefore, BE seems to be a valuable surgical method to improve patients' outcome after PD.

Mechatronic Support System for NOTES and Monoport Surgery - A New Approach.

To circumvent the drawbacks of currently available platforms for natural orifice transluminal endoscopic surgery (NOTES) and monoport surgery (MPS), we developed a patient-specific, disposable, surgical soft robotic system. The system (Single-Port Overtube; SPOT) is designed as an overtube for standard surgical equipment. The platform body and the manipulators can be quickly adapted to transmural (monoport), NOTES and endoluminal (endoscopic) applications, and 3D-printed overnight as an individualized system. In addition, practical considerations, such as the predicted "ideal" dimensions of the platform, were evaluated. As a result, we found that preoperatively available biometric data currently provide little support for tailored instrument design. Further work is required to provide engineers / developers with more useful preoperative information.