Integrating a microRNA signature as a liquid biopsy-based tool for the early diagnosis and prediction of potential therapeutic targets in pancreatic cancer.

INTRODUCTION: Pancreatic cancer is a highly aggressive cancer, and early diagnosis significantly improves patient prognosis due to the early implementation of curative-intent surgery. Our study aimed to implement machine-learning algorithms to aid in early pancreatic cancer diagnosis based on minimally invasive liquid biopsies. MATERIALS AND METHODS: The analysis data were derived from nine public pancreatic cancer miRNA datasets and two sequencing datasets from 26 pancreatic cancer patients treated in our medical center, featuring small RNAseq data for patient-matched tumor and non-tumor samples and serum. Upon batch-effect removal, systematic analyses for differences between paired tissue and serum samples were performed. The robust rank aggregation (RRA) algorithm was used to reveal feature markers that were co-expressed by both sample types. The repeatability and real-world significance of the enriched markers were then determined by validating their expression in our patients' serum. The top candidate markers were used to assess the accuracy of predicting pancreatic cancer through four machine learning methods. Notably, these markers were also applied for the identification of pancreatic cancer and pancreatitis. Finally, we explored the clinical prognostic value, candidate targets and predict possible regulatory cell biology mechanisms involved. RESULTS: Our multicenter analysis identified hsa-miR-1246, hsa-miR-205-5p, and hsa-miR-191-5p as promising candidate serum biomarkers to identify pancreatic cancer. In the test dataset, the accuracy values of the prediction model applied via four methods were 94.4%, 84.9%, 82.3%, and 83.3%, respectively. In the real-world study, the accuracy values of this miRNA signatures were 82.3%, 83.5%, 79.0%, and 82.2. Moreover, elevated levels of these miRNAs were significant indicators of advanced disease stage and allowed the discrimination of pancreatitis from pancreatic cancer with an accuracy rate of 91.5%. Elevated expression of hsa-miR-205-5p, a previously undescribed blood marker for pancreatic cancer, is associated with negative clinical outcomes in patients. CONCLUSION: A panel of three miRNAs was developed with satisfactory statistical and computational performance in real-world data. Circulating hsa-miRNA 205-5p serum levels serve as a minimally invasive, early detection tool for pancreatic cancer diagnosis and disease staging and might help monitor therapy success.

Low skeletal muscle mass and post-operative complications after surgery for liver malignancies: a meta-analysis.

PURPOSE: To assess the influence of low skeletal muscle mass (LSMM) on post-operative complications in patients with hepatic malignancies grade (Clavien Dindo ≥ 3) undergoing resection. METHODS: MEDLINE, Cochrane, and SCOPUS databases were screened for associations between sarcopenia and major post-operative complications (≥ grade 3 according to Clavien-Dindo classification) after resection of different malignant liver tumors. RevMan 5.3 software was used to perform the meta-analysis. The methodological quality of the included studies was assessed according to the QUIPS instrument. RESULTS: The analysis included 17 studies comprising 3157 patients. Subgroup analyses were performed for cholangiocarcinoma (CCC), colorectal cancer (CRC) liver metastases, and hepatocellular carcinoma (HCC). LSMM as identified on CT was present in 1260 patients (39.9%). Analysis of the overall sample showed that LSMM was associated with higher post-operative complications grade Clavien Dindo ≥ 3 (OR 1.56, 95% CI 1.25-1.95, p < 0.001). In the subgroup analysis, LSMM was associated with post-operative complications in CRC metastases (OR 1.60, 95% CI 1.11-2.32, p = 0.01). In HCC and CCC sub-analyses, LSMM was not associated with post-operative complications in simple regression analysis. CONCLUSION: LSMM is associated with major post-operative complications in patients undergoing surgery for hepatic metastases and it does not influence major post-operative complications in patients with HCC and CCC.

Laparoscopic cholecystectomy during the COVID-19 pandemic in a tertiary care hospital in Germany: higher rates of acute and gangrenous cholecystitis in elderly patients.

BACKGROUND: The COVID-19 pandemic caused a global health crisis in 2020. This pandemic also had a negative impact on standard procedures in general surgery. Surgeons were challenged to find the best treatment plans for patients with acute cholecystitis. The aim of this study is to investigate the impact of the COVID-19 pandemic on the outcomes of laparoscopic cholecystectomies performed in a tertiary care hospital in Germany. PATIENTS AND METHODS: We examined perioperative outcomes of patients who underwent laparoscopic cholecystectomy during the pandemic from March 22, 2020 (first national lockdown in Germany) to December 31, 2020. We then compared these to perioperative outcomes from the same time frame of the previous year. RESULTS: A total of 182 patients who underwent laparoscopic cholecystectomy during the above-mentioned periods were enrolled. The pandemic group consisted of 100 and the control group of 82 patients. Subgroup analysis of elderly patients (> 65 years old) revealed significantly higher rates of acute [5 (17.9%) vs. 20 (58.8%); p = 0.001] and gangrenous cholecystitis [0 (0.0%) vs. 7 (20.6%); p = 0.013] in the "pandemic subgroup". Furthermore, significantly more early cholecystectomies were performed in this subgroup [5 (17.9%) vs. 20 (58.8%); p = 0.001]. There were no significant differences between the groups both in the overall and subgroup analysis regarding the operation time, intraoperative blood loss, length of hospitalization, morbidity and mortality. CONCLUSION: Elderly patients showed particularly higher rates of acute and gangrenous cholecystitis during the pandemic. Laparoscopic cholecystectomy can be performed safely in the COVID-19 era without negative impact on perioperative results. Therefore, we would assume that laparoscopic cholecystectomy can be recommended for any patient with acute cholecystitis, including the elderly.

Low skeletal muscle mass in cholangiocarcinoma treated by surgical resection. A meta-analysis.

BACKGROUND: To date, the role of low skeletal muscle mass (LSMM) in cholangiocarcinoma (CC) is unclear. Our purpose was to analyze the influence of LSMM on survival in patients with CC treated by surgical resection. METHODS: MEDLINE, Cochrane, and SCOPUS databases were screened for associations between LSMM and survival in CC up to June 2021. Overall, 16 studies met the inclusion criteria. The methodological quality of the involved studies was analyzed using the QUADAS instrument. The meta-analysis was undertaken using RevMan 5.4 software. RESULTS: The prevalence of LSMM was 48.40%. LSMM was associated with lower overall survival (OS): HR = 2.44, 95%CI = (2.01-2.96) (simple regression); HR = 2.39, 95%CI = (1.83-3.13) (multiple regression). In extrahepatic CC, sarcopenic patients had lower OS, simple regression: HR = 2.11, 95%CI = (1.39-3.20); multiple regression: HR = 2.28, 95%CI = (1.41-3.70). In intrahepatic CC, LSMM predicted recurrence free survival: HR = 2.33, 95%CI = (1.93-2.81) (simple regression); HR = 2.23, 95%CI = (1.73-2.88) (multiple regression). LSMM predicted OS in intrahepatic CC, simple regression: HR = 2.69, 95%CI = (2.24-3.24); multiple regression: HR = 2.43, 95%CI = (1.73-3.41). CONCLUSION: LSMM is a risk factor for OS in patients with CC treated by surgical resection. LSMM is a predictor of RFS in patients with intrahepatic CC.

Incisional hernia after liver transplantation: mesh-based repair and what else?

PURPOSE: Incisional hernia (IH) is not uncommon after liver transplantation (LT). We investigated the long-term outcome of mesh-based hernia repair using an inlay-onlay technique. METHODS: Our analysis was based on a prospective collected database of all LT recipients from our hospital over a period of 15 years. We analyzed clinical data including the period between LT and hernia development, the size and localization of the hernia, the length of in-hospital stay, immunosuppression, and postoperative morbidity, as well as follow-up data. The median follow-up period was 120 (range 12-200) months. RESULTS: Among a total of 220 patients who underwent a collective 239 LTs, 29 (13%) were found to have an IH after a median period of 27.5 months (range 3-96 months). There were 12 (41%) men and 17 (59%) women, with a median age of 51 years. The median size of the IH was 13 cm (range 2-30 cm) and the median in-hospital stay was 6 days. Mild postoperative complications developed in seven patients, including two onlay mesh infections. One patient (3.4%) suffered recurrence. CONCLUSION: Mesh-based hernia repair using the inlay/onlay technique represents an effective and safe method for patients with an IH after LT, without additional risk from continuous immunosuppression.

Robotic and laparoscopic liver surgery for colorectal liver metastases: an experience from a German Academic Center.

BACKGROUND: Minimally invasive liver surgery (MILS) in the treatment of colorectal liver metastases (CRLM) is increasing in incidence. The aim of this work was to present our experience by reporting short-term and long-term outcomes after MILS for CRLM with comparative analysis of laparoscopic (LLS) and robotic liver surgery (RLS). METHODS: Twenty-five patients with CRLM, who underwent MILS between May 2012 and March 2020, were selected from our retrospective registry of minimally invasive liver surgery (MD-MILS). Thirteen of these patients underwent LLS and 12 RLS. Short-term and long-term outcomes of both groups were analyzed. RESULTS: Operating time was significantly longer in the RLS vs. the LLS group (342.0 vs. 200.0 min; p = 0.004). There was no significant difference between the laparoscopic vs. the robotic group regarding length of postoperative stay (8.8 days), measured blood loss (430.4 ml), intraoperative blood transfusion, overall morbidity (20.0%), and liver surgery related morbidity (4%). The mean BMI was 27.3 (range from 19.2 to 44.8) kg/m2. The 30-day mortality was 0%. R0 resection was achieved in all patients (100.0%) in RLS vs. 10 patients (76.9%) in LLS. Major resections were carried out in 32.0% of the cases, and 84.0% of the patients showed intra-abdominal adhesions due to previous abdominal surgery. In 24.0% of cases, the tumor was bilobar, the maximum number of tumors removed was 9, and the largest tumor was 8.5 cm in diameter. The 1-, 3- and 5-year overall survival rates were 84, 56.9, and 48.7%, respectively. The 1- and 3-year overall recurrence-free survival rates were 49.6 and 36.2%, respectively, without significant differences between RLS vs. LLS. CONCLUSION: Minimally invasive liver surgery for CRLM is safe and feasible. Minimally invasive resection of multiple lesions and large tumors is also possible. RLS may help to achieve higher rates of R0 resections. High BMI, previous abdominal surgery, and bilobar tumors are not a barrier for MILS. Laparoscopic and robotic liver resections for CRLM provide similar long-term results which are comparable to open techniques.

Dermatofibrosarcoma protuberans: surgical management of a challenging mesenchymal tumor.

INTRODUCTION: Dermatofibrosarcoma protuberans (DFSP) is a rare, low-grade malignant mesenchymal tumor of the soft tissue, characterized by slow infiltrative growth and common local recurrence, with rare distant metastases. PATIENTS AND METHODS: We present a retrospective study of nineteen patients who were diagnosed with DFSP and operated at our institution in > 10-year period. We examined the clinicopathological parameters with special emphasis on the margin status regarding the clinical outcome and the follow-up. RESULTS: A total of eight cases underwent re-excision at our institution following primary excision or incisional biopsy performed at a different institution. Seven cases received excision after incisional biopsy at our institution. Four patients developed recurrent disease following primary excision with histological R0 margins at other institutions and received re-excision at our institution. All excisions at our institution resulted in R0 margins with no recurrence recorded at last follow-up (6 to 175; mean 84 months). The mean margin for those who received resection at our institution was 1.67 cm. Negative margins upon primary excision were achieved using a mean margin width of 2.04 cm. Most common tumor localization was the trunk (10 cases). CONCLUSION: Awareness of this rare entity is important for a prompt diagnosis and a proper management of the disease. The greatest clinical challenge in the management of DFSP is achieving local control. Complete excision of the tumor with surgical margin widths of at least 2 cm is recommended.

Gastrointestinal schwannomas: a rare but important differential diagnosis of mesenchymal tumors of gastrointestinal tract.

BACKGROUND: Schwannomas of gastrointestinal tract are rare, mostly benign and notably different neoplasms from conventional schwannomas that arise in soft tissue or the central nervous system. These tumors are of clinical importance since they should always be considered in the differential diagnosis of submucosal lesions of gastrointestinal tract. METHODS: Seven patients with a pathologically proven gastrointestinal schwannoma were identified in our series of mesenchymal tumors and reviewed retrospectively. Clinicopathological and immunohistochemical parameters along with the follow-up results were analysed. RESULTS: The series included two males and five females, with a mean age 69 years (range, 39-81). Most patients were asymptomatic on presentation, except for two patients with abdominal pain. In the other cases (n = 5), the tumor was an incidental finding during other medical, imaging or surgical procedures. The tumors were located in the stomach (n = 4) and in the small intestine (n = 3) with an average size of 29 mm (range, 12-70). A preoperative diagnosis was achieved only in one case with a CT-guided core biopsy. Otherwise the clinical, intraoperative, endoscopic or radiological findings were unspecific. Patients with gastric tumor underwent either laparoscopic (n = 2) or open (n = 2) gastric wedge resection of the tumor; in the cases of intestinal tumor (n = 3) a segmentectomy was performed. Pathological examination revealed solid homogenous tumors, which were highly cellular and composed of spindle cells with positive staining for S100 protein, and confirmed the diagnosis of schwannoma. All tumors were negative for c-Kit, smooth muscle actin, desmin and DOG-1 and showed very low proliferation index. There were negative resection margins and no malignant variants were recognized. At an average follow-up of 60 months (range, 24-185) all patients were free of disease with no signs of recurrence or metastases and acceptable gastrointestinal function. CONCLUSIONS: Schwannomas are rare, slow-growing and mostly asymptomatic gastrointestinal mesenchymal tumors. They are difficult to be diagnosed preoperatively as endoscopic and radiological findings are nonspecific but histological and immunohistochemical features are of paramount importance to differentiate between benign and malignant schwannomas, or other spindle cell sarcomas. The treatment of choice is complete surgical excision without a conclusive preoperative diagnosis, and the long-term outcome is excellent as these lesions are mostly benign.

What is Changing in Indications and Treatment of Focal Nodular Hyperplasia of the Liver. Is There Any Place for Surgery?

Focal nodular hyperplasia (FNH) is a common benign liver tumor, which occurs in the vast majority of the cases in young women. FNH represents a polyclonal lesion characterized by local vascular abnormalities and is a truly benign lesion without any potential for malignant transformation. A retrospective single institution analysis of 227 FNH patients, treated from 1990 to 2016 and a review of studies reporting surgical therapy of overall 293 patients with FNH was performed. Indications for resection with a focus on diagnostic workup, patient selection, surgical mode and operative mortality and morbidity have been analysed. Ninety three patients underwent elective hepatectomy and 134 patients observation alone, where median follow-up was 107 months. Postoperative complications were recorded in 14 patients, 92% of patients reported an improvement with respect to their symptoms. Overall among 293 patients underwent surgery in the series, included to this review, there was a morbidity of 13%, where median follow-up was 53 months. Systematic follow-up remains the gold standard in asymptomatic patients with FNH. However elective surgery should be considered in symptomatic patients, in those with marked enlargement and in case of uncertainty of diagnosis. Surgery for FNH is a safe procedure with low morbidity and very good long term results as far as quality of life after surgery is concerned and surely an integral part of the modern management of FNH.

Surgery along the embryological planes for colon cancer: a systematic review of complete mesocolic excision.

BACKGROUND: Complete mesocolic excision (CME) for colonic cancer offers a surgical specimen of higher quality, with higher number of lymph nodes compared to conventional colectomy. However, evidence on oncological outcomes is limited. The aim of the present study is to review recent literature and provide more information regarding the effect of CME colectomy on short- and long-term outcomes. METHOD: PubMed and MEDLINE databases were searched, and articles in English reporting data on CME were reviewed. Intraoperative events; postoperative morbidity and mortality; histopathological characteristics, including macroscopic assessment, number, and status of retrieved lymph nodes; and oncological outcomes were the end-points. RESULTS: Thirty-two studies were analyzed. As regards the macroscopic assessment, a larger specimen (p = 0.02) that contains a higher number of lymph nodes (p < 0.00001) is acquired after CME. Two studies report a higher disease-free survival, in stage I and II and particularly in stage III disease after CME. CME by laparoscopy offers comparable outcomes, as regards intraoperative blood loss and immediate postoperative morbidity and mortality rates. Specimen quality is similar after either approach, for cancers located at the right and left colon, but not at the transverse colon. CONCLUSION: There is strong evidence that CME offers a longer central pedicle that contains more lymph nodes than conventional surgery for colon cancer. CME represents the surgical background for the maximum lymph node harvest, an important quality marker for the surgical outcome. However, and according to present data, there is limited evidence that colectomy in terms of CME leads to improved long-term oncological outcomes.

Lymph node metastasis of carcinomas of transverse colon including flexures. Consideration of the extramesocolic lymph node stations.

PURPOSE: Complete mesocolic excision (CME) is nowadays state of the art in the treatment of colon cancer. In cases of carcinoma of transverse colon and of both flexures an extramesocolic lymph node metastasis can be found in the infrapancreatic lymph node region (ILR) and across the gastroepiploic arcade (GLR). These direct metastatic routes were not previously systematically considered. In order to validate our hypothesis of these direct metastatic pathways and to obtain evidence of our approach of including dissection of these areas as part of CME, we initiated a prospective study evaluating these lymph node regions during surgery. METHODS: Forty-five consecutive patients with primary tumour manifestation in transverse colon and both flexures between May 2010 and January 2013 were prospectively analyzed. Patients were followed up for at least 6 months. Mode of surgery, histopathology, morbidity and mortality were evaluated. RESULTS: Twenty-six patients had a carcinoma of transverse colon, 16 patients one of hepatic flexure and four patients one of splenic flexure. The median lymph node yield was 40. Occurrence of lymph node metastasis in ILR was registered in five patients and in GLR in four patients. The mean lymph node ratio was 0.085. Postoperative complications occurred in nine patients, and postoperative mortality was 2 %. CONCLUSIONS: We were able to demonstrate this novel metastatic route of carcinomas of the transverse colon and of both flexures in ILR and GLR. These could be considered as regional lymph node regions and have to be included into surgery for cancer of the transverse colon including both flexures.

Robotic Complete ALPPS (rALPPS)-First German Experiences.

BACKGROUND: ALPPS leads to fast and effective liver hypertrophy. This enables the resection of extended tumors. Conventional ALPPS is associated with high morbidity and mortality. MILS reduces morbidity and the robot adds technical features that make complex procedures safe. MATERIAL AND METHODS: The MD-MILS was screened for patients who underwent rALPPS. Demographic and perioperative data were evaluated retrospectively. Ninety days postoperative morbidity was scored according to the CD classification. The findings were compared with the literature. RESULTS: Since November 2021, five patients have been identified. The mean age and BMI of the patients were 50.0 years and 22.7 kg/m2. In four cases, patients suffered from colorectal liver metastases and, in one case, intrahepatic cholangiocarcinoma. Prior to the first operation, the mean liver volume of the residual left liver was 380.9 mL with a FLR-BWR of 0.677%. Prior to the second operation, the mean volume of the residual liver was 529.8 mL with a FLR-BWR of 0.947%. This was an increase of 41.9% of the residual liver volume. The first and second operations were carried out within 17.8 days. The mean time of the first and second operations was 341.2 min and 440.6 min. The mean hospital stay was 27.2 days. Histopathology showed the largest tumor size of 39 mm in diameter with a mean amount of 4.7 tumors. The mean tumor-free margin was 12.3 mm. One complication CD > 3a occurred. No patient died during the 90-day follow up. CONCLUSION: In the first German series, we demonstrated that rALPPS can be carried out safely with reduced morbidity and mortality in selected patients.

The Pancreas as a Target of Metastasis from Renal Cell Carcinoma: Is Surgery Feasible and Safe? A Single-Center Experience in a High-Volume and Certified Pancreatic Surgery Center in Germany.

Background: Secondary malignant tumors of the pancreas are rare, representing 2-5% of all pancreatic malignancies. Nevertheless, the pancreas is one of the target organs in cases of metastatic clear cell renal cell carcinoma (CCRCC). Additionally, recurrent metastasis may occur. Surgical resection remains the best and prognostically most favorable therapeutic option in cases of solitary pancreatic metastasis. Aim: To review retrospectively the clinical tumor registry of the University Hospital of Magdeburg, Germany, for this rare entity, performing a clinical systematic single-center observational study (design). Methods: A retrospective cohort analysis of consecutive patients who had undergone pancreatic resection for metastatic CCRC was performed in a single high-volume certified center for pancreatic surgery in Germany from 2010 to 2022. Results: All patients (n = 17) included in this study had a metachronous metastasis from a CCRCC. Surgery was performed at a median time interval of 12 (range, 9-16) years after primary resection for CCRCC. All 17 patients were asymptomatic at the time of diagnosis. Three of those patients (17.6%) presented with recurrent metastasis in a different part of the pancreas during follow-up. In a total of 17 patients, including those with recurrent disease, a surgical resection was performed; Pancreatoduodenectomy was performed in 6 patients (35%); left pancreatectomy with splenectomy was performed in 7 patients (41%). The rest of the patients underwent either a spleen-preserving pancreatic tail resection, local resection of the tumor lesion or a total pancreatectomy. The postoperative mortality rate was 6%. Concerning histopathological findings, seven patients (41%) had multifocal metastasis. An R0 resection could be achieved in all cases. The overall survival at one, three and five years was 85%, 85% and 72%, respectively, during a median follow-up of 43 months. Conclusions: CCRC pancreatic metastases can occur many years after the initial treatment of the primary tumor. Surgery for such a malignancy seems feasible and safe; it offers very good short- and long-term outcomes, as indicated. A repeated pancreatic resection can also be safely performed.

Influence of Certification Program on Treatment Quality and Survival for Rectal Cancer Patients in Germany: Results of 13 Certified Centers in Collaboration with AN Institute.

INTRODUCTION: The certification of oncological units as colorectal cancer centers (CrCCs) has been proposed to standardize oncological treatment and improve the outcomes for patients with colorectal cancer (CRC). The proportion of patients with CRC in Germany that are treated by a certified center is around 53%. Lately, the effect of certification on the treatment outcomes has been critically discussed. AIM: Our aim was to investigate the treatment outcomes in patients with rectal carcinoma at certified CrCCs, in German hospitals of different medical care levels. METHODS: We performed a retrospective analysis of a prospective, multicentric database (AN Institute) of adult patients who underwent surgery for rectal carcinoma between 2002 and 2016. We included 563 patients from 13 hospitals of different medical care levels (basic, priority, and maximal care) over periods of 5 years before and after certification. RESULTS: The certified CrCCs showed a significant increase in the use of laparoscopic approach for rectal cancer surgery (5% vs. 55%, p < 0.001). However, we observed a significantly prolonged mean duration of surgery in certified CrCCs (161 Min. vs. 192 Min., p < 0.001). The overall morbidity did not improve (32% vs. 38%, p = 0.174), but the appearance of postoperative stool fistulas decreased significantly in certified CrCCs (2% vs. 0%, p = 0.036). Concerning the overall in-hospital mortality, we registered a positive trend in certified centers during the five-year period after the certification (5% vs. 3%, p = 0.190). The length of preoperative hospitalization (preop. LOS) was shortened significantly (4.71 vs. 4.13 days, p < 0.001), while the overall length of in-hospital stays was also shorter in certified CrCCs (20.32 vs. 19.54 days, p = 0.065). We registered a clear advantage in detailed, high-quality histopathological examinations regarding the N, L, V, and M.E.R.C.U.R.Y. statuses. In the performed subgroup analysis, a significantly longer overall survival after certification was registered for maximal medical care units (p = 0.029) and in patients with UICC stage IV disease (p = 0.041). In patients with UICC stage III disease, we registered a slightly non-significant improvement in the disease-free survival (UICC III: p = 0.050). CONCLUSIONS: The results of the present study indicate an improvement in terms of the treatment quality and outcomes in certified CrCCs, which is enforced by certification-specific aspects such as a more differentiated surgical approach, a lower rate of certain postoperative complications, and a multidisciplinary approach. Further prospective clinical trials are necessary to investigate the influence of certification in the treatment of CRC patients.

Integrated operation systems and voice recognition in minimally invasive surgery: comparison of two systems.

BACKGROUND: Integrated operation systems were developed for centralization and easy control of all components within the operating room (OR). These systems represent central units that use communication technology to connect and control various components of the OR. Voice control that is independent of the speaker has been a pioneering innovation in the central control of different OR components. The aim of the present study was to evaluate the utility of two voice-activated control systems, the Siemens Integrated OR System (SIOS, Siemens Medical Solutions, Siemens AG) and the OR1 (Karl Storz GmbH & Co. KG), for delivery of commands to specific OR equipment. METHODS: To compare the two systems, actions such as adjusting the operating table, increasing gas pressure, switching on the video recorder, and controlling the endolight source were defined according to a study protocol. These actions were to be executed by test persons through speech and manual control after a suitable training period. The parameters evaluated were training time, time to execute each action, number of repeated commands, and number of functional errors. RESULTS: Seventy-four test persons from five nations were selected to participate. The numbers of repeated commands and functional errors differed significantly between systems in all user groups in favor of the SIOS (mean repeated commands for surgeons: SIOS, 2.4; OR1, 14.7, p < 0.0001). CONCLUSION: The SIOS voice control was more effective and more reliable than that of the OR1. Importantly, unlike the OR1, the SIOS produced no functional errors. The appropriate conditions for greater acceptance of these systems must be considered, together with additional technical improvements and possible combinations of advantages of the available systems.

Management of hemangioma of the liver: surgical therapy or observation?

BACKGROUND: Elective surgery for liver hemangioma is controversial. We reviewed long-term outcomes following elective hepatectomy or observation only for symptomatic and asymptomatic liver hemangioma. METHODS: All patients (n = 307) with liver hemangioma referred to our hospital for surgical evaluation from January 1988 to December 2009 were identified, and imaging results, tumor characteristics, surgical indication, surgical mode, outcome of observation, clinical and/or postoperative outcome, and adverse events were retrospectively evaluated. RESULTS: Complete median follow-up for 246 patients was 124 months. Elective surgery was performed in 103 patients (symptomatic [n = 62] and asymptomatic [n = 41]). Postoperative morbidity occurred in 17 % of the patients and was significantly lower in asymptomatic patients (p = 0.002). No perioperative mortality was registered. Surgery relieved complaints in most (88 %) patients. In the observation group (n = 143), 56 % of patients had persistent or new onset of hemangioma-associated symptoms. Major hemangioma-related complications occurred in 12 patients (9 %) during the follow-up period, and 2 patients died after traumatic hemangioma rupture. Overall the rate of adverse events was by trend lower in the surgical group than in the observation group (35 versus 57 %; p = 0.08). CONCLUSIONS: The majority of patients with liver hemangioma can be safely managed by clinical observation. In a subset of patients, especially those with giant hemangioma and/or occurrence of symptoms, surgical treatment could be considered and is justified in high-volume centers.

RoCS: Robotic Curriculum for young Surgeons.

Robotic-assisted procedures gain increasing acceptance for daily surgical routine. However, structured training programs are designed for surgeons with high expertise. Hence, a comprehensive training curriculum was established to ensure a basic competence in robotic abdominal surgery for young surgeons during their residency. The aim of the current work is to propose a feasible and effective training concept. The development process of this training curriculum is based on a comprehensive literature review which led to the concept of "robotic curriculum for young surgeons" (RoCS). It was implemented in the daily routine of a German university hospital starting in 2020. The robotic assessment questionnaire (RAQ) was used for electronic data collection. After the initial phase adjustments, it led to an improvement of the initial version of the curriculum. RoCS is a multimodal training program containing basic training through assistance at the operation table during robotic-assisted operations and basic console training. Key elements are the robotic team time-out (rTTO), perioperative process standardization including feasible personnel scheduling and useful procedure clustering into organ systems, procedural steps and procedural step complexity. Evaluation of standardized communication, performance assessment, patient factors and individual overall workload using NASA Task Load Index is realizable. Flexibility and adaptability to internal organization processes of surgical departments are the main advantages of the concept. RoCS is a strong training tool to meet the specific needs of young surgeons and evaluate their learning success of robotic procedural training. Furthermore, comparison within the different robotic systems should be considered. Further studies are needed to validate a multicenter concept design.

Concept of a fully-implantable system to monitor tumor recurrence.

Current treatment for glioblastoma includes tumor resection followed by radiation, chemotherapy, and periodic post-operative examinations. Despite combination therapies, patients face a poor prognosis and eventual recurrence, which often occurs at the resection site. With standard MRI imaging surveillance, histologic changes may be overlooked or misinterpreted, leading to erroneous conclusions about the course of adjuvant therapy and subsequent interventions. To address these challenges, we propose an implantable system for accurate continuous recurrence monitoring that employs optical sensing of fluorescently labeled cancer cells and is implanted in the resection cavity during the final stage of tumor resection. We demonstrate the feasibility of the sensing principle using miniaturized system components, optical tissue phantoms, and porcine brain tissue in a series of experimental trials. Subsequently, the system electronics are extended to include circuitry for wireless energy transfer and power management and verified through electromagnetic field, circuit simulations and test of an evaluation board. Finally, a holistic conceptual system design is presented and visualized. This novel approach to monitor glioblastoma patients is intended to early detect recurrent cancerous tissue and enable personalization and optimization of therapy thus potentially improving overall prognosis.