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.

Predicting the HER2 status in oesophageal cancer from tissue microarrays using convolutional neural networks.

BACKGROUND: Fast and accurate diagnostics are key for personalised medicine. Particularly in cancer, precise diagnosis is a prerequisite for targeted therapies, which can prolong lives. In this work, we focus on the automatic identification of gastroesophageal adenocarcinoma (GEA) patients that qualify for a personalised therapy targeting epidermal growth factor receptor 2 (HER2). We present a deep-learning method for scoring microscopy images of GEA for the presence of HER2 overexpression. METHODS: Our method is based on convolutional neural networks (CNNs) trained on a rich dataset of 1602 patient samples and tested on an independent set of 307 patient samples. We additionally verified the CNN's generalisation capabilities with an independent dataset with 653 samples from a separate clinical centre. We incorporated an attention mechanism in the network architecture to identify the tissue regions, which are important for the prediction outcome. Our solution allows for direct automated detection of HER2 in immunohistochemistry-stained tissue slides without the need for manual assessment and additional costly in situ hybridisation (ISH) tests. RESULTS: We show accuracy of 0.94, precision of 0.97, and recall of 0.95. Importantly, our approach offers accurate predictions in cases that pathologists cannot resolve and that require additional ISH testing. We confirmed our findings in an independent dataset collected in a different clinical centre. The attention-based CNN exploits morphological information in microscopy images and is superior to a predictive model based on the staining intensity only. CONCLUSIONS: We demonstrate that our approach not only automates an important diagnostic process for GEA patients but also paves the way for the discovery of new morphological features that were previously unknown for GEA pathology.

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.

Hybrid laparoscopic versus fully robot-assisted minimally invasive esophagectomy: an international propensity-score matched analysis of perioperative outcome.

BACKGROUND: Currently, little is known regarding the optimal technique for the abdominal phase of RAMIE. The aim of this study was to investigate the outcome of robot-assisted minimally invasive esophagectomy (RAMIE) in both the abdominal and thoracic phase (full RAMIE) compared to laparoscopy during the abdominal phase (hybrid laparoscopic RAMIE). METHODS: This retrospective propensity-score matched analysis of the International Upper Gastrointestinal International Robotic Association (UGIRA) database included 807 RAMIE procedures with intrathoracic anastomosis between 2017 and 2021 from 23 centers. RESULTS: After propensity-score matching, 296 hybrid laparoscopic RAMIE patients were compared to 296 full RAMIE patients. Both groups were equal regarding intraoperative blood loss (median 200 ml versus 197 ml, p = 0.6967), operational time (mean 430.3 min versus 417.7 min, p = 0.1032), conversion rate during abdominal phase (2.4% versus 1.7%, p = 0.560), radical resection (R0) rate (95.6% versus 96.3%, p = 0.8526) and total lymph node yield (mean 30.4 versus 29.5, p = 0.3834). The hybrid laparoscopic RAMIE group showed higher rates of anastomotic leakage (28.0% versus 16.6%, p = 0.001) and Clavien Dindo grade 3a or higher (45.3% versus 26.0%, p < 0.001). The length of stay on intensive care unit (median 3 days versus 2 days, p = 0.0005) and in-hospital (median 15 days versus 12 days, p < 0.0001) were longer for the hybrid laparoscopic RAMIE group. CONCLUSIONS: Hybrid laparoscopic RAMIE and full RAMIE were oncologically equivalent with a potential decrease of postoperative complications and shorter (intensive care) stay after full RAMIE.

Perioperative chemotherapy with 5-FU, leucovorin, oxaliplatin, and docetaxel (FLOT) for esophagogastric adenocarcinoma: ten years real-life experience from a surgical perspective.

PURPOSE: According to the results of FLOT4 trial, perioperative FLOT chemotherapy improved overall survival (OS) in locally advanced, resectable esophagogastric adenocarcinoma (EGA) compared to perioperative ECF/ECX. We report real-life data 10 years after introduction of perioperative FLOT at our institution. METHODS: Survival of 356 consecutive EGA patients (cT3/4 and/or cN + and/or cM1) who underwent curative surgical resection was retrospectively analysed from a prospective database. A total of 263 patients received preoperative chemotherapy according to FLOT protocol and 93 patients received an epirubicin/platinum/5FU-based regimen (EPF). Propensity score matching (PSM) according to pretretment characteristics was performed to compensate for heterogeneity between groups. RESULTS: Median OS did not differ between groups (FLOT/EPF 52.1/46.4 months, p = 0.577). After PSM, survival was non-significantly improved after FLOT compared to EPF (median OS not reached/46.4 months, p = 0.156). Perioperative morbidity and mortality did not differ between groups. Histopathologic response rate was 35% after FLOT and 26% after EPF (p = 0.169). R0 resection could be achieved more frequently after FLOT than after EPF (93%/79%, p = 0.023). CONCLUSION: Overall survival after perioperative FLOT followed by surgery is comparable to clinical trials. However, collective real-life application of FLOT failed to provide a significant survival benefit compared to EPF. In clinical reality, patient selection is triggered by age, comorbidity, tumor localization, and clinical tumor stage. Yet matched analyses support FLOT4 trial findings.

Clinical Relevance of Gastroesophageal Cancer Associated SNPs for Oncologic Outcome After Curative Surgery.

BACKGROUND: Gastric and esophageal cancers are malignant diseases with rising importance in Western countries. To improve oncologic outcome after surgery, it is essential to understand the relevance of germline mutations. The aim of the study was to identify and distinguish clinically relevant single-nucleotide polymorphisms (SNPs). PATIENTS AND METHODS: In total, 190 patients with curative oncological resections of gastric and distal esophageal adenocarcinomas at Heidelberg University Hospital were eligible for this study. Outcome differences were determined for each SNP by analysis of clinical variables, survival, and mRNA expression levels. RESULTS: Significant survival differences were found on univariate analysis for usual prognostic variables (such as pTNM) and for six SNPs. On multivariate survival analysis, the SNPs rs12268840 (intron variant of MGMT, p = 0.045) and rs9972882 (intron variant of STARD3 and eQTL of PGAP3, p = 0.030) were independent and significant survival predictors along with R status and pT/pN category. Group TT of rs12268840 had the highest rate of second primary carcinoma (30.4%, p = 0.0003), lowest expression of MGMT based on cis-eQTL analysis in normal gastroesophageal tissue (p = 1.99 × 10-17), and worst oncologic outcome. Group AA of rs9972882 had the highest rate of distant metastases pM1 (42.9%, p = 0.0117), highest expression of PGAP3 (p = 1.29 × 10-15), and worst oncologic outcome. CONCLUSIONS: Two intron variant SNPs of MGMT and STARD3 were identified that were significant survival predictors and may influence tumor biology. The data indicate that DNA methylation (MGMT) and malfunction of GPI anchoring (PGAP3) are distinct mechanisms that are relevant for tumor progression and relapse.

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.

Characteristics and Prognostic Factors of Metachronous Second Primary Upper Gastrointestinal Cancer.

BACKGROUND: Patients with metachronous malignancies before carcinomas of the upper gastrointestinal tract were analyzed regarding clinical parameters, oncological outcome, and prognosis. METHODS: We analyzed the data of 1583 patients with gastroesophageal cancer who underwent oncological resections between 2002 and 2018. Of 1583 patients, 172 had a malignant tumor before the upper gastrointestinal cancer (second primary carcinomas) and 1411 without preceding malignancies served as the control group. The analyses were performed between both groups and within the subgroup of second primary carcinomas. RESULTS: Patients with second primary carcinomas were older (P < 0.0001), had more comorbidities (P < 0.0001), and underwent longer surgical resections (P = 0.0024). They had lower (y)pT-categories (P = 0.0427) and had longer stays in intensive care unit (P = 0.0002) and hospital (P = 0.0018). R0-resection was more frequent (P = 0.0275) while having more surgical complications (P = 0.0378). The median survival was 39.5 mo (primary carcinoma) versus 32.9 mo for (second primary carcinoma) and was not significantly different (P = 0.5359).In the subgroup analysis of second primaries, there were no significant survival differences depending on primary tumor entity (P = 0.4989). pT status (P = 0.0062), pN status (P < 0.0001), pM status (P < 0.0001), and R-status (P < 0.0001) were significant prognostic factors. A time period >9 y after the primary cancer could be identified as a novel and beneficial survival factor (P = 0.0496). Most patients with primary colorectal, prostate, hematogenous, or breast cancer had adenocarcinoma, whereas patients with initial otolaryngologic cancers mainly had squamous cell carcinoma. CONCLUSIONS: Second primary carcinomas of the upper gastrointestinal tract show distinct clinical and oncological characteristics. Common prognostic factors are applicable, and oncologic resection is recommended.

Association of Cerebrospinal Fluid Volume with Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage: A Retrospective Volumetric Analysis.

BACKGROUND: In aneurysmal subarachnoid hemorrhage (SAH), clot volume has been shown to correlate with the development of radiographic vasospasm (VS), while the role of cerebrospinal fluid (CSF) volume remains largely elusive in the literature. We evaluated CSF volume as a potential surrogate for VS in addition to SAH volume in this retrospective series. PATIENTS AND METHODS: From a consecutive cohort of aneurysmal SAH (n= 320), cases were included when angiographic evaluation for VS was performed (n= 125). SAH and CSF volumes were volumetrically quantified using an algorithm-assisted segmentation approach on initial computed tomography after ictus. Association with VS was analyzed using regression analysis. Receiver operating characteristic (ROC) curves were used to evaluate predictive accuracy of volumetric measures for VS and to identify cutoffs for risk stratification. RESULTS: Among 125 included cases, angiography showed VS in 101 (VS+), while no VS was observed in 24 (VS-) cases. In volumetric analysis, mean SAH volume was significantly larger (26.8 ± 21.1 ml vs. 12.6 ± 12.2 ml, p= 0.001), while mean CSF volume was significantly smaller (63.0 ± 31.2 ml vs. 85.7 ± 62.8, p= 0.03) in VS+ compared to VS- cases, respectively. The absence of correlation for SAH and CSF volumes (Pearson R - 0.05, p= 0.58) indicated independence of both measures of the subarachnoid compartment, which was a prerequisite for CSF to act as a new surrogate for VS not related to SAH. Regression analysis confirmed an increased risk of VS with increasing SAH (OR 1.06, 95% CI 1.02-1.11, p= 0.006), while CSF had a protective effect toward VS (OR 0.99, 95% CI 0.98-0.99, p= 0.02). SAH/CSF ratio was also associated with VS (OR 1.03, 95% CI 1.01-1.05, p= 0.015). ROC curves suggested cutoffs at 120 ml CSF and 20 ml SAH for VS stratification. Combination of variables improved stratification accuracy compared to use of SAH alone. CONCLUSION: This study provides a proof of concept for CSF correlating with angiographic VS after aneurysmal SAH. Quantification of CSF in conjunction with SAH might enhance risk stratification and exhibit advantages over traditional scores. The association of CSF has to be corroborated for delayed cerebral ischemia to further establish CSF as a surrogate parameter.

Oligometastatic Gastroesophageal Adenocarcinoma: Molecular Pathophysiology and Current Therapeutic Approach.

Gastric and esophageal cancers are dreaded malignancies, with a majority of patients presenting in either a locally advanced or metastatic state. Global incidences are rising and the overall prognosis remains poor. The concept of oligometastasis has been established for other tumor entities and is also proposed for upper gastrointestinal tract cancers. This review article explores metastasis mechanisms on the molecular level, specific to esophageal and gastric adenocarcinoma. Existing data and recent studies that deal with upper gastrointestinal tumors in the oligometastatic state are reviewed. Furthermore, current therapeutic targets in gastroesophageal cancers are presented and discussed. Finally, a perspective about future diagnostic and therapeutic strategies is given.

Irritative potency of selected wound antiseptics in the hen's egg test on chorioallantoic membrane to predict their compatibility to wounds.

Antiseptics are being used for prevention of infections in acute wounds and for treatment of infections in acute and chronic wounds. However, some antiseptics' high tissue toxicity might delay the healing process. The aim of this study was to investigate the tissue toxicity of preferentially used wound antiseptics and the influence of antiphlogistic additives via the hen's egg test on the chorioallantoic membrane (HET-CAM). The HET-CAM is a semi-in-vivo method testing the tissue tolerability of wound antiseptics by evaluating the blood vessel reaction of the chorioallantoic membrane in terms of hemorrhage, vessel lysis, and coagulation. For each test day, selected test substances were applied on the membranes of two to three eggs according to the test protocol. The overall irritation was then evaluated by referring to a calculated score. Normal distribution of the resulting scores was confirmed by D'Agostino-Pearson omnibus K2 test. Significant differences between the antiseptics were calculated by Tukey's multiple comparisons test. Severe CAM reactions were observed after short-term application of octenidine based wound gel (0.05%) and chlorhexidine digluconate (0.5% solution), moderate reactions for octenidine (0.05%) in aqueous solution combined with dexpanthenol (1.34%) and allantoin (0.2%) or for hydrogen peroxide (1.5% and 0.5%) in aqueous solution, slight reactions were observed for hydrogen peroxide (1.5%) in aqueous solution in combination with sodium thiocyanate (0.698%) and for the combination of NaOCl/HOCl (each 0.004%). Polyhexanide (0.04%) in Ringer solution and polyhexanide (0.05%) in Lipofundin, the hemoglobin spray (10%), dexpanthenol, and allantoin showed no irritation. The HET-CAM qualifies as a primary screening test for tissue tolerance of wound antiseptics. Regarding local tolerability, polyhexanide and hypochlorite are superior to other antiseptics.

[Predictability of anastomotic leaks in visceral surgery]. / Vorhersagbarkeit von Anastomoseninsuffizienzen in der Viszeralchirurgie.

Anastomotic leakage in visceral surgery is associated with a large number of known and also unknown or even unmeasurable parameters. Furthermore, the associations between the individual factors are intertwined and complex. According to current data a preoperative prediction is not reliably possible and should be distinguished from intraoperative or postoperative prediction models. Most studies on this topic do not exceed an area under the curve (AUC) of 0.70. A thorough understanding of statistics and prediction models is necessary to correctly interpret the published works. Due to the relatively low incidence rate of anastomotic leakage from a statistical point of view, large datasets are required for adequate prediction. Multimodal data and complex algorithms can potentially handle big data more accurately and improve predictability; however, these models have so far not been applied in the clinical routine.

Hexokinase 2 as an independent risk factor for worse patient survival in esophageal adenocarcinoma and as a potential therapeutic target protein: A retrospective, single­center cohort study.

Cancer cells exhibit a distinct metabolic profile that features an upregulation of less efficient glycolysis accompanied by lactate production for energy generation, in contract to the characteristic metabolism of normal cells. Consequently, cancer research has focused on the enzymes that participate in these cancer metabolic pathways. Among them, hexokinase 2 (HK2) has an important position as the initial enzyme in the glycolytic pathway. Increased expression levels of HK2 have been correlated with an increased risk of poor patient outcomes and advanced tumor stages in a number of malignant tumors, such as gastric carcinoma. The present study aimed to investigate the specific role of HK2 in patients diagnosed with esophageal adenocarcinoma. A total of 643 patients with esophageal adenocarcinoma were included. Immunohistochemical staining and HK2 mRNA in situ probes were used to investigate the association of HK2 expression levels with clinical and molecular tumor characteristics. Patients who exhibited high HK2 expression levels demonstrated significantly reduced overall survival (OS) times compared with patients who exhibited low HK2 expression levels (29.6 vs. 39.9 months, respectively; P=0.027). Furthermore, high HK2 expression levels were demonstrated to be an independent risk factor for reduced patient survival (hazard ratio, 1.65; 95% CI, 1.09-2.50; P=0.018). Significantly reduced patient survival was also demonstrated in the subgroups of male patients, patients with primarily resected tumors, patients with HER2-negative tumors and patients with tumors exhibiting Y chromosome loss. Elevated expression of HK2 was identified as a risk factor for unfavorable patient survival in esophageal adenocarcinoma. This revelation suggests the potential for future diagnostic and therapeutic avenues tailored to this specific patient subset. Identifying patients with high HK2 expression may pinpoint a higher-risk cohort, paving the way for comprehensive prospective studies that could advocate for intensified monitoring and more aggressive therapeutic regimens. Furthermore, the targeted inhibition of HK2 could hold promise as a strategy to potentially enhance patient outcomes.

Semaphorin 3F (SEMA3F) influences patient survival in esophageal adenocarcinoma.

In esophageal adenocarcinoma, the presence of lymph node metastases predicts patients' survival even after curative resection. Currently, there is no highly accurate marker for detecting the presence of lymph node metastasis. The SEMA3F/NRP2 axis was initially characterized in axon guidance and recent evidence has revealed its significant involvement in lymphangiogenesis, angiogenesis, and carcinogenesis. Hence, the objective of this study was to elucidate the roles of SEMA3F and its receptor NRP2 in esophageal adenocarcinoma. We conducted an immunohistochemical evaluation of SEMA3F and NRP2 protein expression in 776 patients with esophageal adenocarcinoma who underwent Ivor-Lewis esophagectomy at the University Hospital of Cologne. Total and positive cancer cell counts were digitally analyzed using QuPath and verified by experienced pathologists to ensure accuracy. Positive expression was determined as a cell percentage exceeding the 50th percentile threshold. In our cohort, patients exhibiting SEMA3F positive expression experience significantly lower pT- and pN-stages. In contrast, positive NRP2 expression is associated with the presence of lymph node metastases. Survival analyses showed that the expression status of NRP2 had no impact on patient survival. However, SEMA3F positivity was associated with a favorable patient survival outcome (median OS: 38.9 vs. 26.5 months). Furthermore, SEMA3F could be confirmed as an independent factor for better patient survival in patients with early tumor stage (pT1N0-3: HR = 0.505, p = 0.014, pT1-4N0: HR = 0.664, p = 0.024, pT1N0: HR = 0.483, p = 0.040). In summary, SEMA3F emerges as an independent predictor for a favorable prognosis in patients with early-stage esophageal adenocarcinoma. Additionally, NRP2 expression is linked to a higher risk of lymph node metastases occurrence. We hypothesize that low SEMA3F expression could identify patients with early-stage tumors who might benefit from more aggressive treatment options or intensified follow-up. Furthermore, SEMA3F and its associated pathways should be explored as potential tumor-suppressing agents.

The role of length of oral resection margin and survival in esophageal cancer surgery after neoadjuvant therapy: A retrospective propensity score-matched study.

BACKGROUND: Multimodal therapy regimens became the standard of care for patients with esophageal cancer, whereas surgical resection remains at the center of curative treatment modalities. Current guidelines provide no recommendations on the extent of the oral resection margin, especially in the era of neoadjuvant therapy. Therefore, this study aimed to evaluate the relationship between the oral tumor-free resection margin and overall survival. METHODS: Retrospective study with 382 1:1 propensity-matched patients out of 660 patients, operated between 2013 and 2019, with an Ivor-Lewis-esophagectomy for adenocarcinoma and squamous cell carcinoma of the esophagus or esophagogastric junction after neoadjuvant therapy. Independent pathologists measured the oral resection margin after formalin fixation. RESULTS: The mean oral tumor-free resection margin was 37.2 ± 0.6 mm. The ideal cut-off for survival differences was determined for 33 mm. Patients with an oral resection margin of more than 33 mm had a better median overall survival (≤33 mm: 45.0 months, 95% confidence interval: 22.4-67.6 months, >33 mm: not reached, P = .005). An oral resection margin of more than 33 mm proved to be an independent favorable prognostic factor for patients' overall survival in multivariate Cox regression analyses (P = .049). CONCLUSION: This study analyzed a patient cohort retrospectively after curative intended Ivor-Lewis-esophagectomy after neoadjuvant therapy. An oral resection margin of more than 33 mm is a factor for improved overall survival. Therefore, a minimum resection margin of 34 mm after fixation could be suggested.

Targeting the receptor tyrosine kinase MerTK shows therapeutic value in gastric adenocarcinoma.

BACKGROUND: Despite multiple therapeutic modalities, the overall survival of patients with gastric adenocarcinoma remains poor, especially for advanced tumor stages. Although the tyrosine kinase MerTK has shown therapeutic relevance in several tumor entities, its potential effects in gastric adenocarcinoma have not yet been sufficiently characterized. METHODS: MerTK expression and its influence on patient survival were evaluated by immunohistochemistry in a cohort of 140 patients with gastric adenocarcinoma. CRISPR/Cas9 knockout and siRNA knockdown of MerTK in the gastric cancer cell lines SNU1, SNU5, and MKN45 was used to analyze protein expression, growth, migration, and invasion properties in vitro and in a murine xenograft model. MerTK was pharmacologically targeted with the small molecule inhibitor UNC2025 in vitro and in vivo. RESULTS: In patients, high MerTK expression was associated with decreased overall survival (OS) and lymph node metastasis especially in patients without neoadjuvant therapy (p < 0.05). Knockout and knockdown of MerTK reduced cell proliferation and migration both in vitro and in vivo. UNC2025, a small-molecule inhibitor of MerTK, exhibited a significant therapeutic response in vitro and in vivo. Additionally, MerTK expression attenuated the response to neoadjuvant treatment, and its inhibition sensitized tumor cells to 5-Fluorouracil (5-FU)-based chemotherapy in vitro. CONCLUSIONS: Our findings demonstrate the potential value of MerTK as a prognostic biomarker for gastric adenocarcinoma. Targeting MerTK may become a new treatment option, especially for patients with advanced tumors, and may overcome resistance to established chemotherapies.

Deep Learning Histology for Prediction of Lymph Node Metastases and Tumor Regression after Neoadjuvant FLOT Therapy of Gastroesophageal Adenocarcinoma.

BACKGROUND: The aim of this study was to establish a deep learning prediction model for neoadjuvant FLOT chemotherapy response. The neural network utilized clinical data and visual information from whole-slide images (WSIs) of therapy-naïve gastroesophageal cancer biopsies. METHODS: This study included 78 patients from the University Hospital of Cologne and 59 patients from the University Hospital of Heidelberg used as external validation. RESULTS: After surgical resection, 33 patients from Cologne (42.3%) were ypN0 and 45 patients (57.7%) were ypN+, while 23 patients from Heidelberg (39.0%) were ypN0 and 36 patients (61.0%) were ypN+ (p = 0.695). The neural network had an accuracy of 92.1% to predict lymph node metastasis and the area under the curve (AUC) was 0.726. A total of 43 patients from Cologne (55.1%) had less than 50% residual vital tumor (RVT) compared to 34 patients from Heidelberg (57.6%, p = 0.955). The model was able to predict tumor regression with an error of ±14.1% and an AUC of 0.648. CONCLUSIONS: This study demonstrates that visual features extracted by deep learning from therapy-naïve biopsies of gastroesophageal adenocarcinomas correlate with positive lymph nodes and tumor regression. The results will be confirmed in prospective studies to achieve early allocation of patients to the most promising treatment.

Machine learning for optimized individual survival prediction in resectable upper gastrointestinal cancer.

PURPOSE: Surgical oncologists are frequently confronted with the question of expected long-term prognosis. The aim of this study was to apply machine learning algorithms to optimize survival prediction after oncological resection of gastroesophageal cancers. METHODS: Eligible patients underwent oncological resection of gastric or distal esophageal cancer between 2001 and 2020 at Heidelberg University Hospital, Department of General Surgery. Machine learning methods such as multi-task logistic regression and survival forests were compared with usual algorithms to establish an individual estimation. RESULTS: The study included 117 variables with a total of 1360 patients. The overall missingness was 1.3%. Out of eight machine learning algorithms, the random survival forest (RSF) performed best with a concordance index of 0.736 and an integrated Brier score of 0.166. The RSF demonstrated a mean area under the curve (AUC) of 0.814 over a time period of 10 years after diagnosis. The most important long-term outcome predictor was lymph node ratio with a mean AUC of 0.730. A numeric risk score was calculated by the RSF for each patient and three risk groups were defined accordingly. Median survival time was 18.8 months in the high-risk group, 44.6 months in the medium-risk group and above 10 years in the low-risk group. CONCLUSION: The results of this study suggest that RSF is most appropriate to accurately answer the question of long-term prognosis. Furthermore, we could establish a compact risk score model with 20 input parameters and thus provide a clinical tool to improve prediction of oncological outcome after upper gastrointestinal surgery.