Solitary fibrous tumor within the mesorectum: literature review based on a case report of resection by transanal minimally invasive surgery (TAMIS).

PURPOSE: Solitary fibrous tumors (SFT) are a rare entity of in majority benign neoplasms. Nevertheless, up to 20% of cases show a malignant tendency with local infiltration or metastasis. Commonly arising in the thoracic cavity, only few cases of SFT of the mesorectal tissue have been reported in the literature. Complete surgical resection, classically by posterior approach, is the treatment of choice. The purpose of this review is to demonstrate the safety and suitability of transanal minimally invasive surgery (TAMIS) as a surgical approach for the resection of benign pararectal solid tumors. METHODS: We report the case of a 52-year-old man who was diagnosed incidentally with SFT of the distal mesorectum. Resection by TAMIS was performed. Based on this case, we describe the steps and potential benefits of this procedure and provide a comprehensive review of the literature. RESULTS: Histopathology confirms the completely resected SFT. After uneventful postoperative course and discharge on day four, follow-up was recommended by a multidisciplinary board by clinical examination and MRI, which showed a well-healed scar and no recurrence up to 3 years after resection. CONCLUSION: SFT of the mesorectum is a very rare entity. To our knowledge, this is the first report on a TAMIS resection for SFT, demonstrated as a safe approach for complete resection of benign pararectal solid tumors.

There is a need for a paradigm shift in laparoscopic surgical training: results of a nationwide survey among teaching hospitals in Switzerland.

BACKGROUND: Surgical training curricula have changed little over the past decades. Current advances in surgical techniques, especially in minimally invasive surgery, as well as the rapidly changing socioeconomic environment pose a major challenge for the training of young surgeons. The aim of this survey was to provide a representative overview of the surgical training landscape in Switzerland focusing on laparoscopic surgical training: How do department chairs of teaching hospitals deal with the above challenges, and what should a future training curriculum look like? METHODS: This is a prospective, questionnaire-based, cross-sectional study among the heads of departments of all certified surgical teaching hospitals in Switzerland. RESULTS: The overall response rate was 56% (48/86) and 86% (19/22) for tertiary centers. Two-thirds of the centers (32) organize themselves in training networks. Laparoscopic training courses are offered in 25 (52%) hospitals, mainly in tertiary centers. Self-training opportunities exist in 40 (83%) hospitals. In addition to commercial (27) and self-built (7) box trainers, high-fidelity trainers are available in 16 (33%) hospitals. A mandatory training curriculum exists in 7 (15%) facilities, and a training assessment is performed in 15 (31%) institutions. Thirty-two (65%) heads of departments indicated that residents have sufficient practical exposure in the operating room, but the ability to work independently with obtaining the specialist title is seen critically (71%). They state that the surgical catalog does not adequately reflect the manual skills of the resident (64%). The desire is for training to be restructured from a numbers-based to a performance-based curriculum (53%) and for tools to assess residents' manual skills (56%) to be introduced. CONCLUSIONS: Department chairs stated that the existing curriculum in Switzerland does not meet the requirements of a modern training curriculum. This study highlights the need to create an improved, competency-based curriculum that ensures the training of a new generation of surgeons, taking into account the growing evidence of the effectiveness of state-of-the-art training modalities such as simulation or proficiency-based training.

Virtual reality simulation training in laparoscopic surgery - does it really matter, what simulator to use? Results of a cross-sectional study.

BACKGROUND: Virtual reality simulation training plays a crucial role in modern surgical training, as it facilitates trainees to carry out surgical procedures or parts of it without the need for training "on the patient". However, there are no data comparing different commercially available high-end virtual reality simulators. METHODS: Trainees of an international gastrointestinal surgery workshop practiced in different sequences on LaparoS® (VirtaMed), LapSim® (Surgical Science) and LapMentor III® (Simbionix) eight comparable exercises, training the same basic laparoscopic skills. Simulator based metrics were compared between an entrance and exit examination. RESULTS: All trainees significantly improved their basic laparoscopic skills performance, regardless of the sequence in which they used the three simulators. Median path length was initially 830 cm and 463 cm on the exit examination (p < 0.001), median time taken improved from 305 to 167 s (p < 0.001). CONCLUSIONS: All Simulators trained efficiently the same basic surgery skills, regardless of the sequence or simulator used. Virtual reality simulation training, regardless of the simulator used, should be incorporated in all surgical training programs. To enhance comparability across different types of simulators, standardized outcome metrics should be implemented.

Prophylactic funnel mesh to prevent parastomal hernia in permanent end colostomy: A retrospective cohort study.

AIM: This study assessed the impact of a prophylactic, 3D funnel-shaped intraperitoneal mesh on the rate of parastomal hernia after abdominoperineal rectum resection with permanent end colostomy. METHODS: Data from 76 patients receiving permanent end colostomy after abdominoperineal rectum resection between 2013 and 2018 were collected retrospectively. Occurrences of parastomal hernia and reoperation rate due to parastomal hernia in patients with and without a prophylactic mesh were compared by univariate, multivariate, and propensity score-adjusted analyses. RESULTS: Twenty-two (28.9%) of the 76 included patients received a prophylactic mesh. The mean follow-up was 39.3 ± 23.8 months. Mesh implantation reduced the incidence of parastomal hernia to 9.1% (n = 2) compared to 42.6% (n = 23) in patients without a prophylactic mesh. The propensity score-adjusted hazard ratio (HR) was 0.14 (95% confidence interval (CI): 0.04-0.48, p = 0.001). No reoperations due to parastomal hernia were needed in patients who received a prophylactic mesh, while nine patients without mesh (16.7%) required parastomal hernia repair (HR = 0.09, 95% CI: 0.00-1.76, p = 0.015). Mesh implantation was not associated with increased short-term morbidity (Clavien-Dindo grade > 2, 31.8% vs. 40.7%, p = 0.468) or 30-day mortality (4.5% vs. 3.8%, p = 1.000). CONCLUSIONS: Prophylactic implantation of a 3D funnel-shaped intraperitoneal mesh is a safe and effective method to prevent parastomal hernia in patients requiring permanent end colostomy. Mesh placement significantly reduces reoperations due to parastomal hernia.

Simvastatin delay progression of pancreatic intraepithelial neoplasia and cancer formation in a genetically engineered mouse model of pancreatic cancer.

BACKGROUND AND AIMS: Pancreatic cancer is among the most dismal of human malignancies. There are no chemopreventive strategies for pancreatic cancer or its precursor lesions, pancreatic intraepithelial neoplasia (PanINs). Recent evidence suggests that statins have potential chemopreventive abilities. In this study, we used a genetically engineered mouse model of pancreatic cancer to evaluate the chemopreventive potential of this drug. METHODS: Simvastatin was injected i.p. in LsL-Kras(G12D); Pdx1-Cre or LsL-Kras(G12D);LsL-Trp53(R172H);Pdx1-Cre mice. After five months, animals were sacrificed. The effect of simvastatin was evaluated by histopathological analyses, immunostaining, and real-time PCR. RESULTS: After five months of treatment, simvastatin was able to significantly delay progression of mPanINs in LsL-Kras(G12D); Pdx1-Cre mice. Furthermore, formation of invasive pancreatic cancer in LsL-Kras(G12D); LsL-Trp53(R172H); Pdx1-Cre transgenic mice was partially inhibited by simvastatin. Invasive murine pancreatic cancer was identified in 9 of 12 (75%) LsL-Kras(G12D); LsL-Trp53(R172H);Pdx1-Cre untreated control mice. In contrast, transgenic mice treated with Simvastatin, only 4 out of 10 (40%, p = 0.004) developed murine pancreatic cancer during the study. Using real-time PCR we found a significant up-regulation of Hmgcr as sign of blocking HMG-CoA reductase, a key enzyme in the cholesterol biosynthesis. This shows our ability to achieve effective pharmacologic levels of simvastatin during pancreatic cancer formation in vivo. CONCLUSION: Using a transgenic mouse model that recapitulates human pancreatic cancer, this study provides first evidence that simvastatin is an effective chemopreventive agent by delaying the progression of PanINs and partially inhibit the formation of murine pancreatic cancer.

Risk factors and outcomes of postoperative aspiration pneumonia in abdominal surgery patients: An exact matching and weighting analysis.

BACKGROUND: Postoperative aspiration pneumonia is a feared complication contributing significantly to postoperative morbidity and mortality. Over decades, there has been little progress in reducing incidence and mortality of postoperative aspiration pneumonia. Here, we assessed risk factors for postoperative aspiration pneumonia in general and abdominal surgery patients. METHODS: Patients undergoing surgery between January 2012 and December 2018 were included in this exact matched and weighted case-control study. Data from a prospectively acquired clinical database were retrospectively analyzed. RESULTS: Among 23,647 patients undergoing 32,901 operations, 144 (0.44%, 95% Confidence Interval: 0.37%-0.52%) cases of postoperative aspiration pneumonia were identified. Ninety-day mortality was 27.8% (n = 40). Major risk factors for postoperative aspiration pneumonia were emergency surgery in patients with prolonged preoperative fasting (>6 hours; odds ratio: 3.25, 95% confidence interval: 1.46-7.26; P < .001), older age with increasing risk in octogenarians compared to seniors (65-80 years: n = 69; odds ratio 5.23, 95% confidence interval: 2.18-12.51; >80 years: n = 50; odds ratio 13.72, 95% confidence interval: 4.94-38.09; P < .001), American Society of Anesthesiologists scores >II (American Society of Anesthesiologists III: n = 90; odds ratio 3.38, 95% confidence interval: 1.08-16.01; American Society of Anesthesiologists IV/V: n = 18; odds ratio 5.20, 95% confidence interval: 1.48-27.61; P < .001), and body mass index <18 kg/m2 (n = 9; odds ratio: 2.53; 95% confidence interval: 1.04-6.11; P = .029). Laparoscopies (odds ratio 0.45, 95% confidence interval: 0.23-0.88; <0.001) and female sex were associated with a decreased risk for postoperative aspiration pneumonia (odds ratio 0.40, 95% confidence interval: 0.23-0.69; P < .001). CONCLUSION: Preventive measures to reduce postoperative aspiration pneumonia should focus on older patients with American Society of Anesthesiologists scores ≥III undergoing open surgery. Cachectic patients and patients undergoing emergency surgery with prolonged preoperative fasting require increased attention. Laparoscopy was associated with a lower risk for postoperative aspiration pneumonia and should be preferred whenever appropriate.

Chronic pancreatitis and systemic inflammatory response syndrome prevent impact of chemotherapy with gemcitabine in a genetically engineered mouse model of pancreatic cancer.

BACKGROUND AND AIMS: BACKGROUND AND AIMSGemcitabine is the standard therapy for patients with pancreatic cancer with metastatic disease. Patients with metastatic pancreatic cancer presenting with increased values of C-reactive protein do not respond to gemcitabine. So far, no studies have evaluated the correlation between chronic pancreatitis, systemic inflammatory response syndrome, and the loss of chemotherapeutic benefit. METHODS: Pdx-1-Cre;LSL-Kras(G12D/+);LSL-Trp53(R172H/+) mice were assigned into four groups: 1) Sixteen animals received a daily intraperitoneal injection of caerulein from their ninth week of life on. 2) Sixteen mice were additionally given gemcitabine. 3) Twelve animals received gemcitabine only. 4) Saline-treated control group. Furthermore, human Paca44 pancreatic ductal adenocarcinoma cells were seeded and cultured in 0.5% FBS containing growth medium plus/minus 1 µM gemcitabine plus/minus recombinant human interleukin (IL)-6. RESULTS: Induced systemic inflammatory response syndrome and a mild chronic pancreatitis diminished the beneficial effects of gemcitabine upon median overall survival. In median, the monogemcitabine group survived 191 days, whereas the caerulein-mono group survived 114, the control group 121, and the caerulein gemcitabine group 127 days (P < .05). In vitro, the induction of STAT3 phosphorylation by recombinant human IL-6 promoted pancreatic ductal adenocarcinoma cell survival during gemcitabine treatment. CONCLUSION: We could demonstrate for the first time that an improvement in median overall survival with gemcitabine is significantly abolished by a persistent mild chronic pancreatitis and a systemic inflammatory response syndrome. In particular, the inflammation biomarkers C-reactive protein, IL-6, and IL-1α could indicate the prognostic benefit of gemcitabine chemotherapy and should now be tested in prospective patient-controlled trials.