The development of tissue handling skills is sufficient and comparable after training in virtual reality or on a surgical robotic system: a prospective randomized trial.

BACKGROUND: Virtual reality is a frequently chosen method for learning the basics of robotic surgery. However, it is unclear whether tissue handling is adequately trained in VR training compared to training on a real robotic system. METHODS: In this randomized controlled trial, participants were split into two groups for "Fundamentals of Robotic Surgery (FRS)" training on either a DaVinci VR simulator (VR group) or a DaVinci robotic system (Robot group). All participants completed four tasks on the DaVinci robotic system before training (Baseline test), after proficiency in three FRS tasks (Midterm test), and after proficiency in all FRS tasks (Final test). Primary endpoints were forces applied across tests. RESULTS: This trial included 87 robotic novices, of which 43 and 44 participants received FRS training in VR group and Robot group, respectively. The Baseline test showed no significant differences in force application between the groups indicating a sufficient randomization. In the Midterm and Final test, the force application was not different between groups. Both groups displayed sufficient learning curves with significant improvement of force application. However, the Robot group needed significantly less repetitions in the three FRS tasks Ring tower (Robot: 2.48 vs. VR: 5.45; p < 0.001), Knot Tying (Robot: 5.34 vs. VR: 8.13; p = 0.006), and Vessel Energy Dissection (Robot: 2 vs. VR: 2.38; p = 0.001) until reaching proficiency. CONCLUSION: Robotic tissue handling skills improve significantly and comparably after both VR training and training on a real robotic system, but training on a VR simulator might be less efficient.

One model to use them all: training a segmentation model with complementary datasets.

PURPOSE: Understanding surgical scenes is crucial for computer-assisted surgery systems to provide intelligent assistance functionality. One way of achieving this is via scene segmentation using machine learning (ML). However, such ML models require large amounts of annotated training data, containing examples of all relevant object classes, which are rarely available. In this work, we propose a method to combine multiple partially annotated datasets, providing complementary annotations, into one model, enabling better scene segmentation and the use of multiple readily available datasets. METHODS: Our method aims to combine available data with complementary labels by leveraging mutual exclusive properties to maximize information. Specifically, we propose to use positive annotations of other classes as negative samples and to exclude background pixels of these binary annotations, as we cannot tell if a positive prediction by the model is correct. RESULTS: We evaluate our method by training a DeepLabV3 model on the publicly available Dresden Surgical Anatomy Dataset, which provides multiple subsets of binary segmented anatomical structures. Our approach successfully combines 6 classes into one model, significantly increasing the overall Dice Score by 4.4% compared to an ensemble of models trained on the classes individually. By including information on multiple classes, we were able to reduce the confusion between classes, e.g. a 24% drop for stomach and colon. CONCLUSION: By leveraging multiple datasets and applying mutual exclusion constraints, we developed a method that improves surgical scene segmentation performance without the need for fully annotated datasets. Our results demonstrate the feasibility of training a model on multiple complementary datasets. This paves the way for future work further alleviating the need for one specialized large, fully segmented dataset but instead the use of already existing datasets.

Textbook outcome after pancreatoduodenectomy and distal pancreatectomy with postoperative hyperamylasemia-a propensity score matching analysis.

PURPOSE: Postoperative serum hyperamylasemia (POH) is a part of the new, increasingly highlighted, definition for postpancreatectomy pancreatitis (PPAP). This study aimed to analyze whether the biochemical changes of PPAP are differently associated with postoperative complications after distal pancreatectomy (DP) compared with pancreatoduodenectomy (PD). The textbook outcome (TO) was used as a summary measure to capture real-world data. METHODS: The data were retrospectively extracted from a prospective clinical database. Patients with POH, defined as levels above our institution's upper limit of normal on postoperative day 1, after DP and the corresponding propensity score-matched cohort after PD were evaluated on postoperative complications by using logistic regression analyses. RESULTS: We analyzed 723 patients who underwent PD and DP over a period of 9 years. After propensity score matching, 384 patients (192 patients in each group) remained. POH was observed in 78 (41.1%) and 74 (39.4%) after PD and DP correspondingly. There was a significant increase of postoperative complications in the PD group: Clavien-Dindo classification system ≥3 (P < .01 vs P = .71), clinically relevant postoperative pancreatic fistula (P < .001 vs P = .2), postpancreatectomy hemorrhage (P < .001 vs P = .11), and length of hospital stay (P < .001 vs P = .69) if POH occurred compared with in the DP group. TO was significantly unlikely in cases with POH after PD compared with DP (P > .001 vs P = .41). Furthermore, POH was found to be an independent predictor for missing TO after PD (odds ratio [OR], 0.29; 95% CI, 0.14-0.60; P < .001), whereas this was not observed in patients after DP (OR, 0.53; 95% CI, 0.21-1.33; P = .18). CONCLUSION: As a part of the definition for PPAP, POH is a predictive indicator associated with postoperative complications after PD but not after DP.

Preoperative anaemia in distal pancreatectomy: a propensity-score matched analysis.

BACKGROUND: Preoperative anaemia is a prevalent morbidity predictor that adversely affects short- and long-term outcomes of patients undergoing surgery. This analysis aimed to investigate preoperative anaemia and its detrimental effects on patients after distal pancreatectomy. MATERIAL AND METHODS: The present study was a propensity-score match analysis of 286 consecutive patients undergoing distal pancreatectomy. Patients were screened for preoperative anaemia and classified according to WHO recommendations. The primary outcome measure was overall morbidity. The secondary endpoints were in-hospital mortality and rehospitalization. RESULTS: The preoperative anaemia rate before matching was 34.3% (98 patients), and after matching a total of 127 patients (non-anaemic 42 vs. anaemic 85) were included. Anaemic patients had significantly more postoperative major complications (54.1% vs. 23.8%; p < 0.01), a higher comprehensive complication index (26.2 vs. 4.3; p < 0.01), and higher in-hospital mortality rate (14.1% vs. 2.4%; p = 0.04). Multivariate regression analysis confirmed these findings and identified preoperative anaemia as a strong independent risk factor for postoperative major morbidity (OR 4.047; 95% CI: 1.587-10.320; p < 0.01). CONCLUSION: The current propensity-score matched analysis strongly considered preoperative anaemia as a risk factor for major complications following distal pancreatectomy. Therefore, an intense preoperative anaemia workup should be increasingly prioritised.

[The digital operating room : Chances and risks of artificial intelligence]. / Der digitale Operationssaal : Chancen und Risiken künstlicher Intelligenz.

At the central workplace of the surgeon the digitalization of the operating room has particular consequences for the surgical work. Starting with intraoperative cross-sectional imaging and sonography, through functional imaging, minimally invasive and robot-assisted surgery up to digital surgical and anesthesiological documentation, the vast majority of operating rooms are now at least partially digitalized. The increasing digitalization of the whole process chain enables not only for the collection but also the analysis of big data. Current research focuses on artificial intelligence for the analysis of intraoperative data as the prerequisite for assistance systems that support surgical decision making or warn of risks; however, these technologies raise new ethical questions for the surgical community that affect the core of surgical work.

Portable droplet-based real-time monitoring of pancreatic α-amylase in postoperative patients.

Postoperative complications after pancreatic surgery are frequent and can be life-threatening. Current clinical diagnostic strategies involve time-consuming quantification of α-amylase activity in abdominal drain fluid, which is performed on the first and third postoperative day. The lack of real-time monitoring may delay adjustment of medical treatment upon complications and worsen prognosis for patients. We report a bedside portable droplet-based millifluidic device enabling real-time sensing of drain α-amylase activity for postoperative monitoring of patients undergoing pancreatic surgery. Here, a tiny amount of drain liquid of patient samples is continuously collected and co-encapsulated with a starch reagent in nanoliter-sized droplets to track the fluorescence intensity released upon reaction with α-amylase. Comparing the α-amylase levels of 32 patients, 97 % of the results of the droplet-based millifluidic system matched the clinical data. Our method reduces the α-amylase assay duration to approximately 3 min with the limit of detection 7 nmol/s·L, enabling amylase activity monitoring at the bedside in clinical real-time. The presented droplet-based platform can be extended for analysis of different body fluids, diseases, and towards a broader range of biomarkers, including lipase, bilirubin, lactate, inflammation, or liquid biopsy markers, paving the way towards new standards in postoperative patient monitoring.

Exploring semantic consistency in unpaired image translation to generate data for surgical applications.

PURPOSE: In surgical computer vision applications, data privacy and expert annotation challenges impede the acquisition of labeled training data. Unpaired image-to-image translation techniques have been explored to automatically generate annotated datasets by translating synthetic images into a realistic domain. The preservation of structure and semantic consistency, i.e., per-class distribution during translation, poses a significant challenge, particularly in cases of semantic distributional mismatch. METHOD: This study empirically investigates various translation methods for generating data in surgical applications, explicitly focusing on semantic consistency. Through our analysis, we introduce a novel and simple combination of effective approaches, which we call ConStructS. The defined losses within this approach operate on multiple image patches and spatial resolutions during translation. RESULTS: Various state-of-the-art models were extensively evaluated on two challenging surgical datasets. With two different evaluation schemes, the semantic consistency and the usefulness of the translated images on downstream semantic segmentation tasks were evaluated. The results demonstrate the effectiveness of the ConStructS method in minimizing semantic distortion, with images generated by this model showing superior utility for downstream training. CONCLUSION: In this study, we tackle semantic inconsistency in unpaired image translation for surgical applications with minimal labeled data. The simple model (ConStructS) enhances consistency during translation and serves as a practical way of generating fully labeled and semantically consistent datasets at minimal cost. Our code is available at https://gitlab.com/nct_tso_public/constructs .

Intraoperative Wound Irrigation for the Prevention of Surgical Site Infection After Laparotomy: A Randomized Clinical Trial by CHIR-Net.

Importance: Surgical site infections frequently occur after open abdominal surgery. Intraoperative wound irrigation as a preventive measure is a common practice worldwide, although evidence supporting this practice is lacking. Objective: To evaluate the preventive effect of intraoperative wound irrigation with polyhexanide solution. Design, Setting, and Participants: The Intraoperative Wound Irrigation to Prevent Surgical Site Infection After Laparotomy (IOWISI) trial was a multicenter, 3-armed, randomized clinical trial. Patients and outcome assessors were blinded to the intervention. The clinical trial was conducted in 12 university and general hospitals in Germany from September 2017 to December 2021 with 30-day follow-up. Adult patients undergoing laparotomy were eligible for inclusion. The main exclusion criteria were clean laparoscopic procedures and the inability to provide consent. Of 11 700 screened, 689 were included and 557 completed the trial; 689 were included in the intention-to-treat and safety analysis. Interventions: Randomization was performed online (3:3:1 allocation) to polyhexanide 0.04%, saline, or no irrigation (control) of the operative wound before closure. Main Outcome and Measures: The primary end point was surgical site infection within 30 postoperative days according to the US Centers for Disease Control and Prevention definition. Results: Among the 689 patients included, 402 were male and 287 were female. The median (range) age was 65.9 (18.5-94.9) years. Participants were randomized to either wound irrigation with polyhexanide (n = 292), saline (n = 295), or no irrigation (n = 102). The procedures were classified as clean contaminated in 92 cases (8%). The surgical site infection incidence was 11.8% overall (81 of 689), 10.6% in the polyhexanide arm (31 of 292), 12.5% in the saline arm (37 of 295), and 12.8% in the no irrigation arm (13 of 102). Irrigation with polyhexanide was not statistically superior to no irrigation or saline irrigation (hazard ratio [HR], 1.23; 95% CI, 0.64-2.36 vs HR, 1.19; 95% CI, 0.74-1.94; P = .47). The incidence of serious adverse events did not differ among the 3 groups. Conclusions and Relevance: In this study, intraoperative wound irrigation with polyhexanide solution did not reduce surgical site infection incidence in clean-contaminated open abdominal surgical procedures compared to saline or no irrigation. More clinical trials are warranted to evaluate the potential benefit in contaminated and septic procedures, including the emergency setting. Trial Registration: drks.de Identifier: DRKS00012251.

Preoperative IL-8 levels as prognostic indicators of overall survival: an extended follow-up in a prospective cohort with colorectal liver metastases.

INTRODUCTION: CRC with liver metastases is a major contributor to cancer-related mortality. Despite advancements in liver resection techniques, patient survival remains a concern due to high recurrence rates. This study seeks to uncover prognostic biomarkers that predict overall survival in patients undergoing curative hepatic resection for CRC liver metastases. METHODS: Prospectively collected serum samples from a cohort of 49 patients who received curative hepatic resection for CRC liver metastases were studied. The patients are part of a cohort, previously analyzed for perioperative complications (see methods). Various preoperative serum markers, clinical characteristics, and factors were analyzed. Univariate and multivariate Cox regression analyses were conducted to determine associations between these variables and disease-free survival as well as overall survival. RESULTS: For disease-free survival, univariate analysis highlighted the correlation between poor outcomes and advanced primary tumor stage, high ASA score, and synchronous liver metastases. Multivariate analysis identified nodal-positive primary tumors and synchronous metastases as independent risk factors for disease-free survival. Regarding overall survival, univariate analysis demonstrated significant links between poor survival and high preoperative IL-8 levels, elevated neutrophil-lymphocyte ratio (NLR), and presence of metastases in other organs. Multivariate analysis confirmed preoperative IL-8 and having three or more liver metastases as independent risk factors for overall survival. The impact of IL-8 on survival was particularly noteworthy, surpassing the influence of established clinical factors. CONCLUSION: This study establishes preoperative IL-8 levels as a potential prognostic biomarker for overall survival in patients undergoing curative liver resection for CRC liver metastases. This study underscores the importance of incorporating IL-8 and other biomarkers into clinical decision-making, facilitating improved patient stratification and tailored treatment approaches. Further research and validation studies are needed to solidify the clinical utility of IL-8 as a prognostic marker.

Satisfaction of surgeons with the current state of training in minimally invasive surgery: a survey among German surgeons.

BACKGROUND: Minimally invasive surgery (MIS) requires intense education and training with structured supervision and feedback. However, a standardized training structure is lacking in Germany. This nationwide survey aimed to assess the current state of minimally invasive surgery (MIS) training and factors impacting surgeons' satisfaction. METHODS: Between July and October 2021, an online survey was conducted among general, abdominal, and thoracic surgeons in Germany. The survey collected data on department size, individual operative experience, availability of MIS training equipment and curricula, and individual satisfaction with training. A linear regression analysis was conducted to investigate factors influencing the surgeons' satisfaction with the MIS training. RESULTS: A total of 1008 surgeons participated in the survey, including residents (26.1%), fellows (14.6%), attendings (43.8%), and heads of departments (15.2%). Of the respondents, 57.4% reported having access to MIS training equipment, 29.8% and 26% had a curriculum for skills lab MIS training and intraoperative MIS training, respectively. In multivariate linear regression analysis, strongest predictors for surgeons' satisfaction with skills lab MIS training and intraoperative training were the availability of respective training curricula (skills lab: ß 12.572; p < 0.001 & intraoperative: ß 16.541; p < 0.001), and equipment (ß 5.246; p = 0.012 & ß 4.295; p = 0.037), and experience as a first surgeon in laparoscopy (ß 12.572; p < 0.001 & ß 3.748; p = 0.007). Additionally, trainees and teachers differed in their satisfaction factors. CONCLUSION: Germany lacks standardized training curricula and sufficient access to MIS training equipment. Trainees and teachers have distinct factors influencing their satisfaction with MIS training. Standardized curricula, equipment accessibility, and surgical experience are crucial for improving surgeons' satisfaction with training.

Impact of dehydration on laparoscopic performance: a prospective, open-label, randomized cross-over trial.

INTRODUCTION: During laparoscopic surgery, surgeons may experience prolonged periods without fluid intake, which might impact surgical performance, yet there are no objective data investigating this issue. Therefore, the aim of this study was to elucidate the effect of prolonged dehydration on laparoscopic surgical performance and tissue handling. METHODS: A total of 51 laparoscopic novices participated in a single-center, open-label, prospective randomized cross-over trial. All participants were trained to proficiency using a standardized laparoscopic training curriculum. Afterward, all participants performed four different laparoscopic tasks twice, once after 6 h without liquid intake (dehydrated group) and once without any restrictions (control group). Primary endpoints were tissue handling defined by force exertion, task time, and error rate. The real hydration status was assessed by biological parameters, like heart rate, blood pressure, and blood gas analysis. RESULTS: 51 laparoscopic novices finished the curriculum and completed the tasks under both hydrated and dehydrated conditions. There were no significant differences in mean non-zero and peak force between the groups. However, dehydrated participants showed significantly slower task times in the Peg transfer task (hydrated: 139.2 s vs. dehydrated: 147.9 s, p = 0.034) and more errors regarding the precision in the laparoscopic suture and knot task (hydrated: 15.7% accuracy rate vs. dehydrated: 41.2% accuracy rate, p < 0.001). CONCLUSION: Prolonged periods of dehydration do not appear to have a substantial effect on the fundamental tissue handling skills in terms of force exertion among surgical novices. Nevertheless, the observed impact on speed and precision warrants attention.

Development and Validation of a Model for Postpancreatectomy Hemorrhage Risk.

Importance: Postpancreatectomy hemorrhage (PPH) due to postoperative pancreatic fistula (POPF) is a life-threatening complication after pancreatoduodenectomy. However, there is no prediction tool for early identification of patients at high risk of late PPH. Objective: To develop and validate a prediction model for PPH. Design, Setting, and Participants: This retrospective prognostic study included consecutive patients with clinically relevant POPF who underwent pancreatoduodenectomy from January 1, 2009, to May 20, 2023, at the University Hospital Mannheim (derivation cohort), and from January 1, 2012, to May 31, 2022, at the University Hospital Dresden (validation cohort). Data analysis was performed from May 30 to July 29, 2023. Exposure: Clinical and radiologic features of PPH. Main Outcomes and Measures: Accuracy of a predictive risk score of PPH. A multivariate prediction model-the hemorrhage risk score (HRS)-was established in the derivation cohort (n = 139) and validated in the validation cohort (n = 154). Results: A total of 293 patients (187 [64%] men; median age, 69 [IQR, 60-76] years) were included. The HRS comprised 4 variables with associations: sentinel bleeding (odds ratio [OR], 35.10; 95% CI, 5.58-221.00; P < .001), drain fluid culture positive for Candida species (OR, 14.40; 95% CI, 2.24-92.20; P < .001), and radiologic proof of rim enhancement of (OR, 12.00; 95% CI, 2.08-69.50; P = .006) or gas within (OR, 12.10; 95% CI, 2.22-65.50; P = .004) a peripancreatic fluid collection. Two risk categories were identified with patients at low risk (0-1 points) and high risk (≥2 points) to develop PPH. Patients with PPH were predicted accurately in the derivation cohort (C index, 0.97) and validation cohort (C index 0.83). The need for more invasive PPH management (74% vs 34%; P < .001) and severe complications (49% vs 23%; P < .001) were more frequent in high-risk patients compared with low-risk patients. Conclusions and Relevance: In this retrospective prognostic study, a robust prediction model for PPH was developed and validated. This tool may facilitate early identification of patients at high risk for PPH.

Case-Based Serious Gaming for Complication Management in Colorectal and Pancreatic Surgery: Prospective Observational Study.

BACKGROUND: The potential risk and subsequent impact of serious complications after pancreatic and colorectal surgery can be significantly reduced through early recognition, correct assessment, and timely initiation of appropriate therapy. Serious gaming (SG) is an innovative teaching method that combines play with knowledge acquisition, increased concentration, and quick decision-making and could therefore be used for clinically oriented education. OBJECTIVE: This study aims to develop a case-based SG platform for complication management in pancreatic and colorectal surgery, validate the application by comparing game courses of various professional groups in the health care sector, and test the acceptance of the developed platform in the context of clinical education by measuring levels of usability and applicability within the framework of a validity and usefulness analysis. METHODS: In this observational trial, a novel SG for management of postoperative complications was developed and prospectively validated in a cohort of 131 human caregivers with varying experience in abdominal surgery. A total of 6 realistic patient cases were implemented, representing common complications after pancreatic and colorectal surgery. Cases were developed and illustrated using anonymized images, data, and histories of postoperative patients. In the prospective section of this study, following a brief case presentation, participants were asked to triage the virtual patient, make an initial suspected diagnosis, and design a 3-step management plan, throughout which the results of selected diagnostic and therapeutic actions were presented. Participants' proposed case management was compared to ideal case management according to clinical guidelines. Usability, applicability, validity, and acceptance of the application were assessed using the Trier Teaching Evaluation Inventory as part of a noncomparative analysis. In addition, a comparative analysis of conventional teaching and learning formats was carried out. RESULTS: A total of 131 cases were answered. Physicians selected more appropriate therapeutic measures than nonphysicians. In the Trier Teaching Evaluation Inventory, design, structure, relevance, timeliness, and interest promotion were predominantly rated positively. Most participants perceived the application to be superior to conventional lecture-based formats (training courses, lectures, and seminars) in terms of problem-solving skills (102/131, 77.9%), self-reflection (102/131, 77.9%), and usability and applicability (104/131, 79.4%). CONCLUSIONS: Case-based SG has educational potential for complication management in surgery and could thereby contribute to improvements in postoperative patient care.

Active learning for extracting surgomic features in robot-assisted minimally invasive esophagectomy: a prospective annotation study.

BACKGROUND: With Surgomics, we aim for personalized prediction of the patient's surgical outcome using machine-learning (ML) on multimodal intraoperative data to extract surgomic features as surgical process characteristics. As high-quality annotations by medical experts are crucial, but still a bottleneck, we prospectively investigate active learning (AL) to reduce annotation effort and present automatic recognition of surgomic features. METHODS: To establish a process for development of surgomic features, ten video-based features related to bleeding, as highly relevant intraoperative complication, were chosen. They comprise the amount of blood and smoke in the surgical field, six instruments, and two anatomic structures. Annotation of selected frames from robot-assisted minimally invasive esophagectomies was performed by at least three independent medical experts. To test whether AL reduces annotation effort, we performed a prospective annotation study comparing AL with equidistant sampling (EQS) for frame selection. Multiple Bayesian ResNet18 architectures were trained on a multicentric dataset, consisting of 22 videos from two centers. RESULTS: In total, 14,004 frames were tag annotated. A mean F1-score of 0.75 ± 0.16 was achieved for all features. The highest F1-score was achieved for the instruments (mean 0.80 ± 0.17). This result is also reflected in the inter-rater-agreement (1-rater-kappa > 0.82). Compared to EQS, AL showed better recognition results for the instruments with a significant difference in the McNemar test comparing correctness of predictions. Moreover, in contrast to EQS, AL selected more frames of the four less common instruments (1512 vs. 607 frames) and achieved higher F1-scores for common instruments while requiring less training frames. CONCLUSION: We presented ten surgomic features relevant for bleeding events in esophageal surgery automatically extracted from surgical video using ML. AL showed the potential to reduce annotation effort while keeping ML performance high for selected features. The source code and the trained models are published open source.

The Role of Adjuvant Therapy in Duodenal Adenocarcinoma and Intestinal Subtype Ampullary Carcinoma after Curative Resection.

OBJECTIVE: Defining the role of adjuvant therapy in duodenal adenocarcinoma (DAC) and intestinal subtype ampullary carcinoma (iAC). SUMMARY BACKGROUND DATA: DAC and iAC share a similar histological differentiation but the benefit of adjuvant therapy remains unclear. METHODS: Patients undergoing curative-intent surgical resection for DAC and iAC between 2010 and 2021 at five high-volume centers were included. Patient baseline, perioperative and long-term oncological outcomes were evaluated. Statistical testing was performed with SPSS 25 (IBM). RESULTS: A total of 136 patients with DAC and 171 with iAC were identified. Patients with DAC had more advanced tumors than those with iAC. Median overall survival (OS) in DAC patients was 101 months versus 155 months for iAC patients (P=0.098). DAC had a higher rate of local (14.1% vs. 1.2%, P<0.001) and systemic recurrence (30.4% vs. 3.5%, P<0.001). Adjuvant therapy failed to improve overall survival in all patients with DAC and iAC. For DAC, patients with perineural invasion, but not other negative prognostic factors had improved OS rates with adjuvant therapy (72 m vs. 44 m, P=0.044). IAC patients with N+ (190 m vs. 57 m, P=0.003), T3-4 (177 m vs. 59 m, P=0.050) and perineural invasion (150 m vs. 59 m, P=0.019) had improved OS rates with adjuvant therapy. CONCLUSION: While adjuvant therapy fails to improve OS in all patients with DAC and iAC in the current study, it improved overall survival in DAC patients with perineural invasion and in iAC patients with T3-4 tumors, positive lymph nodes, and perineural invasion.

COMPASS: deCOMPressing stomA and two-Stage elective resection vs. emergency reSection in patients with left-sided obstructive colon cancer.

BACKGROUND: Colorectal cancer stands as a prevalent cause of cancer-related mortality, necessitating effective treatment strategies. Acute colonic obstruction occurs in approximately 20% of patients and represents a surgical emergency with substantial morbidity and mortality. The optimal approach for managing left-sided colon cancer with acute colonic obstruction remains debatable, with no consensus on whether emergency resection or bridge-to-surgery, involving initial decompressing stoma and subsequent elective resection after recovery, should be employed. Current studies show a decrease in morbidity and short-term mortality for the bridge-to-surgery approach, yet it remains unclear if the long-term oncological outcome is equivalent to emergency resection. METHODS: This prospective, randomized, multicenter trial aims to investigate the management of obstructive left-sided colon cancer in a comprehensive manner. The study will be conducted across 26 university hospitals and 40 academic hospitals in Germany. A total of 468 patients will be enrolled, providing a cohort of 420 evaluable patients, with an equal distribution of 210 patients in each treatment arm. Patients with left-sided colon cancer, defined as cancer between the left splenic flexure and > 12 cm ab ano and obstruction confirmed by X-ray or CT scan, are eligible. Randomization will be performed in a 1:1 ratio, assigning patients either to the oncological emergency resection group or the bridge-to-surgery group, wherein patients will undergo diverting stoma and subsequent elective oncological resection after recovery. The primary endpoint of this trial will be 120-day mortality, allowing for consideration of the time interval between diverting stoma and resection. DISCUSSION: The findings derived from this trial possess the potential to reshape the current clinical approach of emergency resection for obstructive left-sided colon cancer by favoring the bridge-to-surgery practice, provided that a reduction in morbidity can be achieved without compromising the oncological long-term outcome. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) under the identifier DRKS00031827. Registered on May 15, 2023. PROTOCOL: 28.04.2023, protocol version 2.0F.

Treatment of Colorectal Cancer in Certified Centers: Results of a Large German Registry Study Focusing on Long-Term Survival.

(1) Background: The WiZen study is the largest study so far to analyze the effect of the certification of designated cancer centers on survival in Germany. This certification program is provided by the German Cancer Society (GCS) and represents one of the largest oncologic certification programs worldwide. Currently, about 50% of colorectal cancer patients in Germany are treated in certified centers. (2) Methods: All analyses are based on population-based clinical cancer registry data of 47.440 colorectal cancer (ICD-10-GM C18/C20) patients treated between 2009 and 2017. The primary outcome was 5-year overall survival (OAS) after treatment at certified cancer centers compared to treatment at other hospitals; the secondary endpoint was recurrence-free survival. Statistical methods included Kaplan-Meier analysis and multivariable Cox regression. (3) Results: Treatment at certified hospitals was associated with significant advantages concerning 5-year overall survival (HR 0.92, 95% CI 0.89, 0.96, adjusted for a broad range of confounders) for colon cancer patients. Concentrating on UICC stage I-III patients, for whom curative treatment is possible, the survival benefit was even larger (colon cancer: HR 0.89, 95% CI 0.84, 0.94; rectum cancer: HR 0.91, 95% CI 0.84, 0.97). (4) Conclusions: These results encourage future efforts for further implementation of the certification program. Patients with colorectal cancer should preferably be directed to certified centers.