Treatment of local recurrence of esophageal cancer following Ivor-Lewis esophagectomy-Experiences of a high-volume center.

PURPOSE: Patients with local recurrence of esophageal cancer have a highly decreased overall survival. There is currently no standardized treatment algorithm for this group. This retrospective cohort study aimed to evaluate the survival of patients with local recurrence, despite receiving individualized treatment options. METHODS: 241 of 1791 patients were diagnosed with a local recurrence following Ivor-Lewis esophagectomy at the University Hospital of Cologne. 59 patients, who were diagnosed only with a local recurrence of adeno- or squamous cell carcinoma and received their individualized therapy regimes at our high-volume center, were included. RESULTS: The study included 52 patients with adenocarcinoma and 7 with squamous cell carcinoma. Among these, 6 patients underwent resection, 19 received solely chemotherapy, 29 received chemoradiotherapy, and 5 were provided with best supportive care. Patients who underwent resection showed a better survival outcome compared to patients without resection (median OS: not reached vs. 15.1 months, p = 0.012). Best supportive care and palliative care were found to be independent risk factors for shorter overall survival compared to curative intended treatment options like local resection or chemoradiotherapy. CONCLUSION: In this study, different treatment strategies for patients with local recurrence of esophageal cancer were depicted. Resection as well as chemoradiotherapy could play a role in selected patients. Further prospective studies are needed to improve the selection of eligible patients.

A senior surgical resident can safely perform complex esophageal cancer surgery after surgical mentoring program-experience of a European high-volume center.

Previous studies have shown that surgical residents can safely perform a variation of complex abdominal surgeries when provided with adequate training, proper case selection, and appropriate supervision. Their outcomes are equivalent when compared to experienced board-certified surgeons. Our previously published training curriculum for robotic assisted minimally invasive esophagectomy already demonstrated a possible reduction in time to reach proficiency. However, esophagectomy is a technically challenging procedure and comes with high morbidity rates of up to 60%, making it difficult to provide opportunities to train surgical residents. We aimed to investigate if a surgical resident could safely perform complex esophageal surgery when a structured modular teaching curriculum is applied. A structured teaching program based on our previously published modular step-up approach was applied by two experienced board-certified esophageal surgeons. Our IRB-approved (Institutional Review Board) database was searched to identify all Ivor-Lewis esophagectomies performed by the selected surgical resident from August 2019 to July 2021. The cumulative sum method was used to analyze the learning curve of the surgical resident. Outcomes of patients operated by the resident were then compared to our overall cohort of open, hybrid, and robotic Ivor-Lewis esophagectomies from May 2016 to May 2020. The total cohort included 567 patients, of which 65 were operated by the surgical resident and 502 patients were operated by experienced esophageal cancer surgeons as the control group. For baseline characteristics, a significant difference for BMI (Body mass index) was observed, which was lower in the resident's group (25.5 kg/m2 vs. 26.8 kg/m2 (P = 0.046). A significant difference of American Society of Anesthesiologists- and Eastern Cooperative Oncology Group-scores was seen, and a subgroup analysis including all patients with American Society of Anesthesiologists I and Eastern Cooperative Oncology Group 0 was performed revealing no significant differences. Postoperative complications did not differ between groups. The anastomotic leak rate was 13.8% in the resident's cohort and 12% in the control cohort (P = 0.660). Major complications (Clavien-Dindo ≥ IIIb) occurred in 16.9% of patients in both groups. Oncological outcome, defined by harvested lymph nodes (35 vs. 32.33, P = 0.096), proportion of lymph node compliant performed operations (86.2% vs. 88.4%, P = 0.590), and R0-resection rate (96.9% vs. 96%, P = 0.766), was not compromised when esophagectomies were performed by the resident. The resident completed the learning curves after 39 cases for the total operating time, 38 cases for the thoracic operating time, 26 cases for the number of harvested lymph nodes, 29 cases for anastomotic leak rate, and finally 58 cases for the comprehensive complication index. For postoperative complications, no significant difference was seen between patients operated in the resident group versus the control group, with a third of patients being discharged with a textbook outcome in both cohorts. Furthermore, no difference in oncological quality of the resection was found, emphasizing safety and feasibility of our training program. A structured modular step-up for training a surgical resident to perform complex esophageal cancer surgery can successfully maintain patient safety and outcomes.

Long-Term Postsurgical Outcomes of Neoadjuvant Chemoradiation (CROSS) Versus Chemotherapy (FLOT) for Multimodal Treatment of Adenocarcinoma of the Esophagus and the Esophagogastric Junction.

BACKGROUND: The question of the ideal neoadjuvant therapy for locally advanced esophagogastric adenocarcinoma has not been answered to date. Multimodal treatment has become a standard treatment for these adenocarcinomas. Currently, perioperative chemotherapy (FLOT) or neoadjuvant chemoradiation (CROSS) is recommended. METHODS: A monocentric retrospective analysis compared long-term survival after CROSS versus FLOT. The study enrolled patients with adenocarcinoma of the esophagus (EAC) or the esophagogastric junction type I or II undergoing oncologic Ivor-Lewis esophagectomy between January 2012 and December 2019. The primary objective was to determine the long-term outcome in terms of overall survival. The secondary objectives were to determine differences regarding the histopathologic categories after neoadjuvant treatment and the histomorphologic regression. RESULTS: The findings showed no survival advantage for one or the other treatment in this highly standardized cohort. All the patients underwent open (CROSS: 9.4% vs. FLOT: 22%), hybrid (CROSS: 82% vs. FLOT: 72%), or minimally invasive (CROSS: 8.9% vs. FLOT: 5.6%) thoracoabdominal esophagectomy. The median post-surgical follow-up period was 57.6 months (95% confidence interval [CI] 23.2-109.7 months), and the median survival was longer for the CROSS patients (54 months) than for the FLOT patients (37.2 months) (p = 0.053). The overall 5-years survival was 47% for the entire cohort (48% for the CROSS and 43% for the FLOT patients). The CROSS patients showed a better pathologic response and fewer advanced tumor stages. CONCLUSION: The improved pathologic response after CROSS cannot be translated into longer overall survival. To date, the choice of which neoadjuvant treatment to use can be made only on the basis of clinical parameters and the patient's performance status.

Prediction of postoperative complications after oesophagectomy using machine-learning methods.

BACKGROUND: Oesophagectomy is an operation with a high risk of postoperative complications. The aim of this single-centre retrospective study was to apply machine-learning methods to predict complications (Clavien-Dindo grade IIIa or higher) and specific adverse events. METHODS: Patients with resectable adenocarcinoma or squamous cell carcinoma of the oesophagus and gastro-oesophageal junction who underwent Ivor Lewis oesophagectomy between 2016 and 2021 were included. The tested algorithms were logistic regression after recursive feature elimination, random forest, k-nearest neighbour, support vector machine, and neural network. The algorithms were also compared with a current risk score (the Cologne risk score). RESULTS: 457 patients had Clavien-Dindo grade IIIa or higher complications (52.9 per cent) versus 407 patients with Clavien-Dindo grade 0, I, or II complications (47.1 per cent). After 3-fold imputation and 3-fold cross-validation, the overall accuracies were: logistic regression after recursive feature elimination, 0.528; random forest, 0.535; k-nearest neighbour, 0.491; support vector machine, 0.511; neural network, 0.688; and Cologne risk score, 0.510. For medical complications, the results were: logistic regression after recursive feature elimination, 0.688; random forest, 0.664; k-nearest neighbour, 0.673; support vector machine, 0.681; neural network, 0.692; and Cologne risk score, 0.650. For surgical complications, the results were: logistic regression after recursive feature elimination, 0.621; random forest, 0.617; k-nearest neighbour, 0.620; support vector machine, 0.634; neural network, 0.667; and Cologne risk score, 0.624. The calculated area under the curve of the neural network was 0.672 for Clavien-Dindo grade IIIa or higher, 0.695 for medical complications, and 0.653 for surgical complications. CONCLUSION: The neural network scored the highest accuracies compared with all of the other models for the prediction of postoperative complications after oesophagectomy.

The human gullet or stomach can develop tumours. Surgery can help to cure patients with these tumours. But the operation is risky because sometimes adverse events can happen afterwards. So far, there is no reliable prediction model. It may help to predict the risk of adverse events accurately. For example, patients with a high risk could be observed more thoroughly. Patients with a low risk may not need unnecessary procedures. The information of all patients with an operation at a specialized hospital was collected. Machine learning is a complex mathematical method and was used in this study. It is able to analyse big data sets of information. One machine-learning method called neural network was best in predicting adverse events. Right now, the performance may not be strong enough to fully rely on the prediction. However, refinement of the prediction and more data could improve the neural network in the future.

High NANOG expression correlates with worse patients' survival in esophageal adenocarcinoma.

BACKGROUND: Patients diagnosed with esophageal cancer demonstrate a low overall survival even despite the established multimodal therapy as the current standard of care. Therefore, further biomarkers for patients with high-risk and additional therapy options are needed. NANOG is a transcription factor, which can be found in stem cells and is known to support tumorigenesis. METHODS: Six hundred sixty patients with esophageal adenocarcinoma, who were operated at the University of Cologne with a curative intent, were included. Immunohistochemical stainings for NANOG were performed. The study population was divided into NANOG-positive and -negative subgroups. RESULTS: Positive NANOG expression correlates significantly with worse overall survival (p = 0.002) and could be confirmed as an independent risk factor for worse patient survival in multivariate analysis (HR = 1.40, 95%CI = 1.09-1.80, p = 0.006). This effect could be detected in the subgroup of primarily operated patients, but not in patients after neoadjuvant therapy. CONCLUSIONS: We describe a NANOG-positive subgroup of patients with esophageal cancer, who exhibit worse overall survival in a large patient cohort. This discovery suggests the potential use of NANOG as a biomarker for both intensified therapy and stricter follow-up regimes. Additionally, NANOG-positive stem cell-like cancer cells could be used as a new antitumoral treatment target if validated in mechanistic and clinical studies.

Time to endoscopic vacuum therapy-lessons learned after > 150 robotic-assisted minimally invasive esophagectomies (RAMIE) at a German high-volume center.

OBJECTIVE OF THE STUDY: In esophageal surgery, anastomotic leak (AL) remains one of the most severe and critical adverse events after oncological esophagectomy. Endoscopic vacuum therapy (EVT) can be used to treat AL; however, in the current literature, treatment outcomes and reports on how to use this novel technique are scarce. The aim of this study was to evaluate the outcomes of patients with an AL after IL RAMIE and to determine whether using EVT as an treatment option is safe and feasible. MATERIAL AND METHODS: This study includes all patients who developed an Esophagectomy Complications Consensus Group (ECCG) type II AL after IL RAMIE at our center between April 2017 and December 2021. The analysis focuses on time to EVT, duration of EVT, and follow up treatments for these patients. RESULTS: A total of 157 patients underwent an IL RAMIE at our hospital. 21 patients of these (13.4%) developed an ECCG type II AL. One patient died of unrelated Covid-19 pneumonia and was excluded from the study cohort. The mean duration of EVT was 12 days (range 4-28 days), with a mean of two sponge changes (range 0-5 changes). AL was diagnosed at a mean of 8 days post-surgery (range 2-16 days). Closure of the AL with EVT was successful in 15 out of 20 patients (75%). Placement of a SEMS (Self-expandlable metallic stent) after EVT was performed in four patients due to persisting AL. Overall success rate of anastomotic sealing independently of the treatment modality was achieved in 19 out of 20 Patients (95%). No severe EVT-related adverse events occurred. CONCLUSION: This study shows that EVT can be a safe and effective endoscopic treatment option for ECCG type II AL.

Analysis of training pathway to reach expert performance levels based on proficiency-based progression in robotic-assisted minimally invasive esophagectomy (RAMIE).

BACKGROUND: Robotic-assisted minimally invasive esophagectomy (RAMIE) was first introduced in 2003 and has since then shown to significantly improve the postoperative course. Previous studies have shown that a structured training pathway based on proficiency-based progression using individual skill levels as measures of reach of competence can enhance surgical performance. The aim of this study was to evaluate and help understand our pathway to reach surgical expert levels using a proficiency-based approach introducing RAMIE at our German high-volume center. METHODS: All patients undergoing RAMIE performed by two experienced surgeons for esophageal cancer since the introduction of the robotic technique in 2017 was included in this analysis. Intraoperative outcomes and postoperative outcomes were included in the analysis. The cumulative sum method was used to analyze how many cases are needed to reach expert levels for different performance characteristics and skill sets during robotic-assisted minimally invasive esophagectomy. RESULTS: From 06/2017 to 03/2022, a total of 154 patients underwent RAMIE at our facility and were included in the analysis. An advancement in performance level was observed for total operating time after 70 cases and for thoracic operative time after 79 cases. Lymph node yield showed an increase up until case 60 in the CUSUM analysis. Length of hospital stay stabilized after case 55. The CCI score inflection point was at case 55 in both CUSUM and regression analyses. Anastomotic leak rate stabilized at case 38 and showed another inflection point after case 83. CONCLUSION: Our data and analysis showed the progression from proficient to expert performance levels during the implementation of RAMIE at a European high-volume center. Further analysis of surgeons, especially with a different training status has yet to reveal if the caseloads found in this study are universally applicable. However, skill acquisition and respective measures of such are diverse and as a great range of number of cases was observed, we believe that the learning curve and ascent in performance levels cannot be defined by one parameter alone.

Clinical utility and applicability of the,Esophagus Complication Consensus Group' (ECCG) classification of anastomotic leakage following hybrid Ivor-Lewis esophagectomy.

BACKGROUND: Anastomotic leakage (AL) remains the leading surgical complication following Ivor-Lewis (IL) esophagectomy. Different treatment options of AL exist but outcome is difficult to compare due to a lack of generally accepted classifications. This retrospective study was conducted to analyze the clinical significance of a recently proposed classification based on the management of AL. PATIENTS AND METHODS: A cohort of 954 consecutive patients undergoing hybrid IL esophagectomy (laparoscopy/thoracotomy) was analysed. AL was defined according to the,Esophagus Complication Consensus Group' (ECCG) criteria depending on its treatment: conservative (AL type I), interventional endoscopic (AL type II), and surgical (AL type III). Primary outcome was single or multiple organ failure (Clavien-Dindo IVA/B) associated with AL. RESULTS: Overall morbidity was 63.0% and 8.8% (84/954 patients) developed an AL postoperatively. Three patients (3.5%) had an AL type I, 57 patients (67.9%) an AL type II and 24 patients (28.6%) an AL type III. For patients managed surgically, AL was diagnosed significantly earlier (median days: AL type III: 2 vs AL type II: 6, p < 0.001). Associated organ failure (CD IVA/B) was significantly lower for AL type II as compared to AL type III (21.1% versus 45.8%, p < 0.0001). In-hospital mortality was 3.5% for AL type II and 8.3% for AL type III (p = 0.789). There was no difference for re-admission to ICU and overall length of hospital stay. CONCLUSION: The proposed ECCG classification is simply to apply and discriminates the post-treatment severity of AL but does not aid to implement a treatment algorithm.

Laparoscopic ischemic conditioning prior esophagectomy in selected patients: the ISCON trial.

Anastomotic leakage (AL) after esophagectomy is the most impactful complication after esophagectomy. Ischemic conditioning (ISCON) of the stomach >14 days prior to esophagectomy might reduce the incidence of AL. The current trial was conducted to prospectively investigate the safety and feasibility of laparoscopic ISCON in selected patients. This international multicenter feasibility trial included patients with esophageal cancer at high risk for AL with major calcifications of the thoracic aorta or a stenosis in the celiac trunk. Patients underwent laparoscopic ISCON by occlusion of the left gastric and the short gastric arteries followed by esophagectomy after an interval of 12-18 days. The primary endpoint was complications Clavien-Dindo ≥ grade 2 after ISCON and before esophagectomy. Between November 2019 and January 2022, 20 patients underwent laparoscopic ISCON followed by esophagectomy. Out of 20, 16 patients (80%) underwent neoadjuvant treatment. The median duration of the laparoscopic ISCON procedure was 45 minutes (range: 25-230). None of the patients developed intraoperative or postoperative complications after ISCON. Hospital stay after ISCON was median 2 days (range: 2-4 days). Esophagectomy was completed in all patients after a median of 14 days (range: 12-28). AL occurred in three patients (15%), and gastric tube necrosis occurred in one patient (5%). In hospital, the 30-day and 90-day mortalities were 0%. Laparoscopic ISCON of the gastric conduit is feasible and safe in selected esophageal cancer patients with an impaired vascular status. Further studies have to prove whether this innovative strategy aids to reduce the incidence of AL.

Acoustic source characterization of simulated subsonic jet noise using spherical harmonics.

As subsonic jets remain one of the major contributions to aircraft noise emissions, near-field flow simulations should be included in aircraft design at an early stage using quantitatively predicted sound pressure levels and the time-domain signal properties of the noise data. In this regard, the interface from the near-field data to the far-field radiation-under consideration of acoustic reflections from objects such as fuselage and wings-remains as bottleneck. This study presents the computation of a spherical equivalent source model of jet noise with minimal complexity by means of spherical harmonic (SH) coefficients. Using spherical Hankel extrapolation of sound pressure data from virtual, concentrical microphone arrays, the results of the determination for the radius, in which all acoustic sources of a flow field are confined, indicate the source radius around the end of the potential core to be equivalent to five times the nozzle diameter. The result of the SH transform shows the dominant energy contribution to be related to nine elementary sources. The resulting equivalent source model of jet noise provides a convenient format for further use in large-scale computational fluid dynamics simulations.

Isolation and characterization of a main porin from the outer membrane of Salinibacter ruber.

Salinibacter ruber is an extremophilic bacterium able to grow in high-salts environments, such as saltern crystallizer ponds. This halophilic bacterium is red-pigmented due to the production of several carotenoids and their derivatives. Two of these pigment molecules, salinixanthin and retinal, are reported to be essential cofactors of the xanthorhodopsin, a light-driven proton pump unique to this bacterium. Here, we isolate and characterize an outer membrane porin-like protein that retains salinixanthin. The characterization by mass spectrometry identified an unknown protein whose structure, predicted by AlphaFold, consists of a 8 strands beta-barrel transmembrane organization typical of porins. The protein is found to be part of a functional network clearly involved in the outer membrane trafficking. Cryo-EM micrographs showed the shape and dimensions of a particle comparable with the ones of the predicted structure. Functional implications, with respect to the high representativity of this protein in the outer membrane fraction, are discussed considering its possible role in primary functions such as the nutrients uptake and the homeostatic balance. Finally, also a possible involvement in balancing the charge perturbation associated with the xanthorhodopsin and ATP synthase activities is considered.

Outcomes after totally minimally invasive versus hybrid and open Ivor Lewis oesophagectomy: results from the International Esodata Study Group.

BACKGROUND: Large studies comparing totally minimally invasive oesophagectomy (TMIE) with laparoscopically assisted (hybrid) oesophagectomy are lacking. Although randomized trials have compared TMIE invasive with open oesophagectomy, daily clinical practice does not always resemble the results reported in such trials. The aim of the present study was to compare complications after totally minimally invasive, hybrid and open Ivor Lewis oesophagectomy in patients with oesophageal cancer. METHODS: The study was performed using data from the International Esodata Study Group registered between February 2015 and December 2019. The primary outcome was pneumonia, and secondary outcomes included the incidence and severity of anastomotic leakage, (major) complications, duration of hospital stay, escalation of care, and 90-day mortality. Data were analysed using multivariable multilevel models. RESULTS: Some 8640 patients were included between 2015 and 2019. Patients undergoing TMIE had a lower incidence of pneumonia than those having hybrid (10.9 versus 16.3 per cent; odds ratio (OR) 0.56, 95 per cent c.i. 0.40 to 0.80) or open (10.9 versus 17.4 per cent; OR 0.60, 0.42 to 0.84) oesophagectomy, and had a shorter hospital stay (median 10 (i.q.r. 8-16) days versus 14 (11-19) days (P = 0.041) and 11 (9-16) days (P = 0.027) respectively). The rate of anastomotic leakage was higher after TMIE than hybrid (15.1 versus 10.7 per cent; OR 1.47, 1.01 to 2.13) or open (15.1 versus 7.3 per cent; OR 1.73, 1.26 to 2.38) procedures. CONCLUSION: Compared with hybrid and open Ivor Lewis oesophagectomy, TMIE resulted in a lower pneumonia rate, a shorter duration of hospital stay, but higher anastomotic leakage rates. Therefore, no clear advantage was seen for either TMIE, hybrid or open Ivor Lewis oesophagectomy when performed in daily clinical practice.

Robot-assisted minimally invasive esophagectomy (RAMIE) vs. hybrid minimally invasive esophagectomy: propensity score matched short-term outcome analysis of a European high-volume center.

INTRODUCTION: Transthoracic esophagectomy is a highly complex and sophisticated procedure with high morbidity rates and a significant mortality. Surgical access has consistently become less invasive, transitioning from open esophagectomy to hybrid esophagectomy (HE) then to totally minimally invasive esophagectomy (MIE), and most recently to robot-assisted minimally invasive esophagectomy (RAMIE), with each step demonstrating improved patient outcomes. Aim of this study with more than 600 patients is to complete a propensity-score matched comparison of postoperative short-term outcomes after highly standardized RAMIE vs. HE in a European high volume center. PATIENTS AND METHODS: Six hundred and eleven patients that underwent transthoracic Ivor-Lewis esophagectomy for esophageal cancer between May 2016 and May 2021 were included in the study. In January 2019, we implemented an updated robotic standardized anastomotic technique using a circular stapler and ICG (indocyanine green) for RAMIE cases. Data were retrospectively analyzed from a prospectively maintained IRB-approved database. Outcomes of patients undergoing standardized RAMIE from January 2019 to May 2021 were compared to our overall cohort from May 2016-April 2021 (HE) after a propensity-score matching analysis was performed. RESULTS: Six hundred and eleven patients were analyzed. 107 patients underwent RAMIE. Of these, a total of 76 patients underwent a robotic thoracic reconstruction using the updated standardized circular stapled anastomosis (RAMIE group). A total of 535 patients underwent HE (Hybrid group). Seventy patients were propensity-score matched in each group and analysis revealed no statistically significant differences in baseline characteristics. RAMIE patients had a significantly shorter ICU stay (p = 0.0218). Significantly more patients had no postoperative complications (Clavien Dindo 0) in the RAMIE group [47.1% vs. 27.1% in the HE group (p = 0.0225)]. No difference was seen in lymph node yield and R0 resection rates. Anastomotic leakage rates when matched were 14.3% in the hybrid group vs. 4.3% in the RAMIE group (p = 0.07). CONCLUSION: Our analysis confirms the safety and feasibility of RAMIE and HE in a large cohort after propensity score matching. A regular postoperative course (Clavien-Dindo 0) and a shorter ICU stay were seen significantly more often after RAMIE compared to HE. Furthermore it shows that both procedures provide excellent short-term oncologic outcomes, regarding lymph node harvest and R0 resection rates. A randomized controlled trial comparing RAMIE and HE is still pending and will hopefully contribute to ongoing discussions.

Allicin as a Volatile or Nebulisable Antimycotic for the Treatment of Pulmonary Mycoses: In Vitro Studies Using a Lung Flow Test Rig.

Fungal infections of the lung are an increasing problem worldwide and the search for novel therapeutic agents is a current challenge due to emerging resistance to current antimycotics. The volatile defence substance allicin is formed naturally by freshly injured garlic plants and exhibits broad antimicrobial potency. Chemically synthesised allicin was active against selected fungi upon direct contact and via the gas phase at comparable concentrations to the pharmaceutically used antimycotic amphotericin B. We investigated the suppression of fungal growth by allicin vapour and aerosols in vitro in a test rig at air flow conditions mimicking the human lung. The effect of allicin via the gas phase was enhanced by ethanol. Our results suggest that allicin is a potential candidate for development for use in antifungal therapy for lung and upper respiratory tract infections.

The Effect of Postoperative Complications After Minimally Invasive Esophagectomy on Long-term Survival: An International Multicenter Cohort Study.

BACKGROUND: Esophagectomy is a technically challenging procedure, associated with significant morbidity. The introduction of minimally invasive esophagectomy (MIE) has reduced postoperative morbidity. OBJECTIVE: Although the short-term effect on complications is increasingly being recognized, the impact on long-term survival remains unclear. This study aims to investigate the association between postoperative complications following MIE and long-term survival. METHODS: Data were collected from the EsoBenchmark Collaborative composed by 13 high-volume, expert centers routinely performing MIE. Patients operated between June 1, 2011 and May 31, 2016 were included. Complications were graded using the Clavien-Dindo (CD) classification. To correct for short-term effects of postoperative complications on mortality, patients who died within 90 days postoperative were excluded. Primary endpoint was 5-year overall survival. RESULTS: A total of 915 patients were included with a mean follow-up time of 30.8 months (standard deviation 17.9). Complications occurred in 542 patients (59.2%) of which 50.2% had a CD grade ≥III complication [ie, (re)intervention, organ dysfunction, or death]. The incidence of anastomotic leakage (AL) was 135 of 915 patients (14.8%) of which 84 patients were classified as a CD grade ≥III. Multivariable analysis showed a significantly deteriorated long-term survival in all patients with AL [hazard ratio (HR) 1.68, 95% confidence interval (CI) 1.25-2.24]. This inverse relation was most distinct when AL was scored as a CD grade ≥III (HR 1.83, 95% CI 1.30-2.58). For all other complications, no significant association with long-term survival was found. CONCLUSION: The occurrence and severity of AL, but not overall complications, after MIE negatively affect long-term survival of esophageal cancer patients.

Safety of Esophageal Cancer Surgery During the First Wave of the COVID-19 Pandemic in Europe: A Multicenter Study.

BACKGROUND: Many hospitals postponed elective surgical care during the first wave of the coronavirus disease 2019 (COVID-19) pandemic. Some centers continued elective surgery, including esophageal cancer surgery, with the use of preoperative screening methods; however, there is no evidence supporting the safety of this strategy as postoperative outcomes after esophageal cancer surgery during the COVID-19 pandemic have not yet been investigated. METHODS: This multicenter study in four European tertiary esophageal cancer referral centers included consecutive adult patients undergoing elective esophageal cancer surgery from a prospectively maintained database in a COVID-19 pandemic cohort (1 March 2020-31 May 2020) and a control cohort (1 October 2019-29 February 2020). The primary outcome was the rate of respiratory failure requiring mechanical ventilation. RESULTS: The COVID-19 cohort consisted of 139 patients, versus 168 patients in the control cohort. There was no difference in the rate of respiratory failure requiring mechanical ventilation (13.7% vs. 8.3%, p = 0.127) and number of pulmonary complications (32.4% vs. 29.9%, p = 0.646) between the COVID-19 cohort and the control cohort. Overall, postoperative morbidity and mortality rates were comparable between both cohorts. History taking and reverse transcription polymerase chain reaction (RT-PCR) were used as preoperative screening methods to detect a possible severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in all centers. No patients were diagnosed with COVID-19 pre- or postoperatively. CONCLUSION: Esophageal cancer surgery during the first wave of the COVID-19 pandemic was not associated with an increase in pulmonary complications as no patients were diagnosed with COVID-19. Esophageal cancer surgery can be performed safely with the use of adequate preoperative SARS-CoV-2 screening methods.

Technique of open and minimally invasive intrathoracic reconstruction following esophagectomy-an expert consensus based on a modified Delphi process.

BACKGROUND: In recent years, minimally invasive Ivor Lewis (IL) esophagectomy with high intrathoracic anastomosis has emerged as surgical standard of care for esophageal cancer in expert centers. Alongside this process, many divergent technical aspects of this procedure have been devised in different centers. This study aims at achieving international consensus on the surgical steps of IL reconstruction using Delphi methodology. METHODS: The expert panel consisted of specialized esophageal surgeons from 8 European countries. During a two-round Delphi process, a detailed analysis and consensus on key steps of intrathoracic gastric tube reconstruction (IL esophagectomy) was performed. RESULTS: Response rates in Delphi rounds 1 and 2 were 100% (22 of 22 experts) and 83.3% (20 of 24 experts), respectively. Three essential technical areas of intrathoracic gastric tube reconstruction were identified: first, vascularization of the gastric conduit, second, gastric mobilization, tube formation and pull-up, and third, anastomotic technique. In addition, 3 main techniques for minimally invasive intrathoracic anastomosis are currently practiced: (i) end-to-side circular stapled, (ii) end-to-side double stapling, and (iii) side-to-side linear stapled technique. The step-by-step procedural analysis unveiled common approaches but also different expert practice. CONCLUSION: This precise technical description may serve as a clinical guideline for intrathoracic reconstruction after esophagectomy. In addition, the results may aid to harmonize the technical evolution of this complex surgical procedure and thereby facilitate surgical training.

Surgical Morbidity and Mortality From the Multicenter Randomized Controlled NeoRes II Trial: Standard Versus Prolonged Time to Surgery After Neoadjuvant Chemoradiotherapy for Esophageal Cancer.

OBJECTIVE: To investigate if prolonged TTS after completed nCRT improves postoperative outcomes for esophageal and esophagogastric junction cancer. SUMMARY OF BACKGROUND DATA: TTS has traditionally been 4-6 weeks after completed nCRT. However, the optimal timing is not known. METHODS: A multicenter clinical trial was performed with randomized allocation of TTS of 4-6 or 10-12 weeks. The primary endpoint of this sub-study was overall postoperative complications defined as Clavien-Dindo grade II-V. Secondary endpoints included complication severity according to Clavien-Dindo grade IIIb-V, postoperative 90-day mortality, and length of hospital stay. The study was registered in Clinicaltrials.gov (NCT02415101). RESULTS: In total 249 patients were randomized. There were no significant differences between standard TTS and prolonged TTS with regard to overall incidence of complications Clavien-Dindo grade II-V (63.2% vs 72.6%, P = 0.134) or regarding Clavien-Dindo grade IIIb-V complications (31.6% vs 34.9%, P = 0.603). There were no statistically significant differences between standard and prolonged TTS regarding anastomotic leak (P = 0.596), conduit necrosis (P = 0.524), chyle leak (P = 0.427), pneumonia (P = 0.548), and respiratory failure (P = 0.723). In the standard TTS arm 5 patients (4.3%) died within 90 days of surgery, compared to 4 patients (3.8%) in the prolonged TTS arm (P = 1.0). Median length of hospital stay was 15 days in the standard TTS arm and 17 days in the prolonged TTS arm (P = 0.234). CONCLUSION: The timing of surgery after completed nCRT for carcinoma of the esophagus or esophagogastric junction, is not of major importance with regard to short-term postoperative outcomes.

The Low Molecular Mass Photosystem II Protein PsbTn Is Important for Light Acclimation.

Photosystem II (PSII) is a supramolecular complex containing over 30 protein subunits and a large set of cofactors, including various pigments and quinones as well as Mn, Ca, Cl, and Fe ions. Eukaryotic PSII complexes contain many subunits not found in their bacterial counterparts, including the proteins PsbP (PSII), PsbQ, PsbS, and PsbW, as well as the highly homologous, low-molecular-mass subunits PsbTn1 and PsbTn2 whose function is currently unknown. To determine the function of PsbTn1 and PsbTn2, we generated single and double psbTn1 and psbTn2 knockout mutants in Arabidopsis (Arabidopsis thaliana). Cross linking and reciprocal coimmunoprecipitation experiments revealed that PsbTn is a lumenal PSII protein situated next to the cytochrome b 559 subunit PsbE. The removal of the PsbTn proteins decreased the oxygen evolution rate and PSII core phosphorylation level but increased the susceptibility of PSII to photoinhibition and the production of reactive oxygen species. The assembly and stability of PSII were unaffected, indicating that the deficiencies of the psbTn1 psbTn2 double mutants are due to structural changes. Double mutants exhibited a higher rate of nonphotochemical quenching of excited states than the wild type and single mutants, as well as slower state transition kinetics and a lower quantum yield of PSII when grown in the field. Based on these results, we propose that the main function of the PsbTn proteins is to enable PSII to acclimate to light shifts or intense illumination.

The CARDIA-trial protocol: a multinational, prospective, randomized, clinical trial comparing transthoracic esophagectomy with transhiatal extended gastrectomy in adenocarcinoma of the gastroesophageal junction (GEJ) type II.

BACKGROUND: Adenocarcinoma of the gastroesophageal junction (GEJ) Siewert type II can be resected by transthoracic esophagectomy or transhiatal extended gastrectomy. Both allow for a complete tumor resection, yet there is an ongoing controversy about which surgical approach is superior with regards to quality of life, oncological outcomes and survival. While some studies suggest a better oncological outcome after transthoracic esophagectomy, others favor transhiatal extended gastrectomy for a better postoperative quality of life. To date, only retrospective studies are available, showing ambiguous results. METHODS: This study is a multinational, multicenter, randomized, clinical superiority trial. Patients (n = 262) with a GEJ type II tumor resectable by both transthoracic esophagectomy and transhiatal extended gastrectomy will be enrolled in the trial. Type II tumors are defined as tumors with their midpoint between ≤1 cm proximal and ≤ 2 cm distal of the top of gastric folds on preoperative endoscopy. Patients will be included in one of the participating European sites and are randomized to either transthoracic esophagectomy or transhiatal extended gastrectomy. The trial is powered to show superiority for esophagectomy with regards to the primary efficacy endpoint overall survival. Key secondary endpoints are complete resection (R0), number and localization of tumor infiltrated lymph nodes at dissection, post-operative complications, disease-free survival, quality of life and cost-effectiveness. Postoperative survival and quality of life will be followed-up for 24 months after discharge. Further survival follow-up will be conducted as quarterly phone calls up to 60 months. DISCUSSION: To date, as level 1 evidence is lacking, there is no consensus on which surgery is superior and both surgeries are used to treat GEJ type II carcinoma worldwide. The CARDIA trial is the first randomized trial to compare transthoracic esophagectomy versus transhiatal extended gastrectomy in patients with GEJ type II tumors. Several quality control measures were implemented in the protocol to ensure data reliability and increase the trial's significance. It is hypothesized that esophagectomy allows for a higher rate of radical resections and a more complete mediastinal lymph node dissection, resulting in a longer overall survival, while still providing an acceptable quality of life and cost-effectiveness. TRIAL REGISTRATION: The trial was registered on August 2nd 2019 at the German Clinical Trials Register under the trial-ID DRKS00016923 .