Endoscopic papillectomy for ampullary lesions of minor papilla.

BACKGROUND AND AIMS: Ampullary lesions (ALs) of the minor duodenal papilla are extremely rare. Endoscopic papillectomy (EP) is a routinely used treatment for AL of the major duodenal papilla, but the role of EP for minor AL has not been accurately studied. METHODS: We identified 20 patients with ALs of minor duodenal papilla in the multicentric database from the Endoscopic Papillectomy vs Surgical Ampullectomy vs Pancreatitcoduodenectomy for Ampullary Neoplasm study, which included 1422 EPs. We used propensity score matching (nearest-neighbor method) to match these cases with ALs of the major duodenal papilla based on age, sex, histologic subtype, and size of the lesion in a 1:2 ratio. Cohorts were compared by means of chi-square or Fisher exact test as well as Mann-Whitney U test. RESULTS: Propensity score-based matching identified a cohort of 60 (minor papilla 20, major papilla 40) patients with similar baseline characteristics. The most common histologic subtype of lesions of minor papilla was an ampullary adenoma in 12 patients (3 low-grade dysplasia and 9 high-grade dysplasia). Five patients revealed nonneoplastic lesions. Invasive cancer (T1a), adenomyoma, and neuroendocrine neoplasia were each found in 1 case. The rate of complete resection, en-bloc resection, and recurrences were similar between the groups. There were no severe adverse events after EP of lesions of minor papilla. One patient had delayed bleeding that could be treated by endoscopic hemostasis, and 2 patients showed a recurrence in surveillance endoscopy after a median follow-up of 21 months (interquartile range, 12-50 months). CONCLUSIONS: EP is safe and effective in ALs of the minor duodenal papilla. Such lesions could be managed according to guidelines for EP of major duodenal papilla.

Endoscopic and Surgical Management of Non-Metastatic Ampullary Neuroendocrine Neoplasia: A Multi-Institutional Pancreas2000/EPC Study.

INTRODUCTION: Ampullary neuroendocrine neoplasia (NEN) is rare and evidence regarding their management is scarce. This study aimed to describe clinicopathological features, management, and prognosis of ampullary NEN according to their endoscopic or surgical management. METHODS: From a multi-institutional international database, patients treated with either endoscopic papillectomy (EP), transduodenal surgical ampullectomy (TSA), or pancreaticoduodenectomy (PD) for ampullary NEN were included. Clinical features, post-procedure complications, and recurrences were assessed. RESULTS: 65 patients were included, 20 (30.8%) treated with EP, 19 (29.2%) with TSA, and 26 (40%) with PD. Patients were mostly asymptomatic (n = 46; 70.8%). Median tumor size was 17 mm (12-22), tumors were mostly grade 1 (70.8%) and pT2 (55.4%). Two (10%) EP resulted in severe American Society for Gastrointestinal Enterology (ASGE) adverse post-procedure complications and 10 (50%) were R0. Clavien 3-5 complications did not occur after TSA and in 4, including 1 postoperative death (15.4%) of patients after PD, with 17 (89.5%) and 26 R0 resection (100%), respectively. The pN1/2 rate was 51.9% (n = 14) after PD. Tumor size larger than 1 cm (i.e., pT stage >1) was a predictor for R1 resection (p < 0.001). Three-year overall survival and disease-free survival after EP, TSA, and PD were 92%, 68%, 92% and 92%, 85%, 73%, respectively. CONCLUSION: Management of ampullary NEN is challenging. EP should not be performed in lesions larger than 1 cm or with a endoscopic ultrasonography T stage beyond T1. Local resection by TSA seems safe and feasible for lesions without nodal involvement. PD should be preferred for larger ampullary NEN at risk of nodal metastasis.

Substance-specific importance of EGFR for vascular smooth muscle cells motility in primary culture.

Besides their importance for the vascular tone, vascular smooth muscle cells (VSMC) also contribute to pathophysiological vessel alterations. Various G-protein coupled receptor ligands involved in vascular dysfunction and remodeling can transactivate the epidermal growth factor receptor (EGFR) of VSMC, yet the importance of EGFR transactivation for the VSMC phenotype is incompletely understood. The aims of this study were (i) to characterize further the importance of the VSMC-EGFR for proliferation, migration and marker gene expression for inflammation, fibrosis and reactive oxygen species (ROS) homeostasis and (ii) to test the hypothesis that vasoactive substances (endothelin-1, phenylephrine, thrombin, vasopressin and ATP) rely differentially on the EGFR with respect to the abovementioned phenotypic alterations. In primary, aortic VSMC from mice without conditional deletion of the EGFR, proliferation, migration, marker gene expression (inflammation, fibrosis and ROS homeostasis) and cell signaling (ERK 1/2, intracellular calcium) were analyzed. VSMC-EGFR loss reduced collective cell migration and single cell migration probability, while no difference between the genotypes in single cell velocity, chemotaxis or marker gene expression could be observed under control conditions. EGF promoted proliferation, collective cell migration, chemokinesis and chemotaxis and leads to a proinflammatory gene expression profile in wildtype but not in knockout VSMC. Comparing the impact of five vasoactive substances (all reported to transactivate EGFR and all leading to an EGFR dependent increase in ERK1/2 phosphorylation), we demonstrate that the importance of EGFR for their action is substance-dependent and most apparent for crowd migration but plays a minor role for gene expression regulation.

Consequences of postnatal vascular smooth muscle EGFR deletion on acute angiotensin II action.

Epi dermal growth factor (EGF) receptor (EGFR) is activated by its canonical ligands and transactivated by various vasoactive substances, e.g. angiotensin II (Ang II). Vascular EGFR has been proposed to be involved in vascular tissue homoeostasis and remodelling. Thus, most studies have focused on its role during long-term vascular changes whereas the relevance for acute regulation of vascular function in vivo and ex vivo is insufficiently understood. To investigate the postnatal role of VSMCs (vascular smooth muscle cells) EGFR in vivo and ex vivo, we generated a mouse model with cell-specific and inducible deletion of VSMC EGFR and studied the effect on basal blood pressure, acute pressure response to, among others, Ang II in vivo as well as ex vivo, cardiovascular tissue homoeostasis and vessel morphometry in male mice. In knockout (KO) animals, systolic, diastolic and mean blood pressures were reduced compared with wild-type (WT). Furthermore, Ang II-induced pressure load was lower in KO animals, as was Ang II-induced force development and extracellular-signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation in aortic rings from KO animals. By contrast, we observed no difference in force development during application of serotonin, KCl, endothelin-1 or endothelin-1-induced pressure load in KO animals. In addition, nitric oxide (NO)-mediated vasodilation was not affected. Heart weight (HW) increase and up-regulation of aortic and cardiac expression of Ccl2 (chemoattractant protein-2) and serpinE1 (plasminogen activator inhibitor 1) during the transition from 4- to 10-months of age were prevented by VSMC EGFR KO. We conclude that VSMC EGFR is involved in basal blood pressure homoeostasis and acute pressure response to Ang II, and thereby contributes to maturation-related remodelling.

Outcomes of rescue procedures in the management of locally recurrent ampullary tumors: A Pancreas 2000/EPC study.

BACKGROUND: Ampullary lesions are rare and can be locally treated either with endoscopic papillectomy or transduodenal surgical ampullectomy. Management of local recurrence after a first-line treatment has been poorly studied. METHODS: Patients with a local recurrence of an ampullary lesion initially treated with endoscopic papillectomy or transduodenal surgical ampullectomy were retrospectively included from a multi-institutional database (58 centers) between 2005 and 2018. RESULTS: A total of 103 patients were included, 21 (20.4%) treated with redo endoscopic papillectomy, 14 (13.6%) with transduodenal surgical ampullectomy, and 68 (66%) with pancreaticoduodenectomy. Redo endoscopic papillectomy had low morbidity with 4.8% (n = 1) severe to fatal complications and a R0 rate of 81% (n = 17). Transduodenal surgical ampullectomy and pancreaticoduodenectomy after a first procedure had a higher morbidity with Clavien III and more complications, respectively, 28.6% (n = 4) and 25% (n = 17); R0 resection rates were 85.7% (n = 12) and 92.6% (n = 63), both without statistically significant difference compared to endoscopic papillectomy (P = .1 and 0.2). Pancreaticoduodenectomy had 4.4% (n = 2) mortality. No deaths were registered after transduodenal surgical ampullectomy or endoscopic papillectomy. Recurrences treated with pancreaticoduodenectomy were more likely to be adenocarcinomas (79.4%, n = 54 vs 21.4%, n = 3 for transduodenal surgical ampullectomy and 4.8%, n = 1 for endoscopic papillectomy, P < .0001). Three-year overall survival and disease-free survival were comparable. CONCLUSION: Endoscopy is appropriate for noninvasive recurrences, with resection rate and survival outcomes comparable to surgery. Surgery applies more to invasive recurrences, with transduodenal surgical ampullectomy rather for carcinoma in situ and early cancers and pancreaticoduodenectomy for more advanced tumors.

Systematic Review with Meta-Analysis: Endoscopic and Surgical Resection for Ampullary Lesions.

Ampullary lesions (ALs) can be treated by endoscopic (EA) or surgical ampullectomy (SA) or pancreaticoduodenectomy (PD). However, EA carries significant risk of incomplete resection while surgical interventions can lead to substantial morbidity. We performed a systematic review and meta-analysis for R0, adverse-events (AEs) and recurrence between EA, SA and PD. Electronic databases were searched from 1990 to 2018. Outcomes were calculated as pooled means using fixed and random-effects models and the Freeman-Tukey-Double-Arcsine-Proportion-model. We identified 59 independent studies. The pooled R0 rate was 76.6% (71.8-81.4%, I2 = 91.38%) for EA, 96.4% (93.6-99.2%, I2 = 37.8%) for SA and 98.9% (98.0-99.7%, I2 = 0%) for PD. AEs were 24.7% (19.8-29.6%, I2 = 86.4%), 28.3% (19.0-37.7%, I2 = 76.8%) and 44.7% (37.9-51.4%, I2 = 0%), respectively. Recurrences were registered in 13.0% (10.2-15.6%, I2 = 91.3%), 9.4% (4.8-14%, I2 = 57.3%) and 14.2% (9.5-18.9%, I2 = 0%). Differences between proportions were significant in R0 for EA compared to SA (p = 0.007) and PD (p = 0.022). AEs were statistically different only between EA and PD (p = 0.049) and recurrence showed no significance for EA/SA or EA/PD. Our data indicate an increased rate of complete resection in surgical interventions accompanied with a higher risk of complications. However, studies showed various sources of bias, limited quality of data and a significant heterogeneity, particularly in EA studies.

Study Protocol of the ESAP Study: Endoscopic Papillectomy vs. Surgical Ampullectomy vs. Pancreaticoduodenectomy for Ampullary Neoplasm-A Pancreas2000/EPC Study.

Background: Lesions of the Ampulla of Vater are a rare condition and represent <10% of peri-ampullary neoplasms. Nevertheless, ampullary adenomas have the potential for malignant transformation to ampullary carcinomas by an adenoma-to-carcinoma sequence. Thus, adequate patient selection and complete resection (R0) of non-invasive ampullary lesions either by endoscopic papillectomy (EP), surgical ampullectomy (SA), or pancreaticoduodenectomy (PD) is essential. Although PD was traditionally performed, recent studies reported considerable efficacy and fewer complications following EP and SA. Since consistent comparative data are lacking, the Endoscopic Papillectomy vs. Surgical Ampullectomy vs. Pancreaticoduodectomy (ESAP) study will provide evidence for a therapeutic standard and post procedure morbidity in ampullary lesions. Methods: International multicenter retrospective study. Adult patients (>18 years of age) who underwent SA or PD for ampullary neoplasm between 2004 and 2018 or EP between 2007 and 2018 will be evaluated. Main inclusion criteria are ampullary lesions strictly located to the ampulla. This includes adenoma, adenocarcinoma (T1 and T2), neuroendocrine tumors, gastrointestinal stroma tumors and other rare conditions. Exclusion criteria are peri-ampullary lesions, e.g., from the duodenal wall or the head of the pancreas, and interventions for tumor stages higher than T2. The main objective of this study is to analyze rates of complete resection (R0), recurrence and necessity for complementary interventions following EP, SA, and PD. Treatment-quality for each procedure will be defined by morbidity, mortality and complication rates and will be compared between EP, SA, and PD. Secondary objectives include outcome for patients with incomplete resection or initially understated tumors, lesions of the minor papilla, hereditary syndromes, neuroendocrine tumors, mesenchymal lesions, and other rare conditions. Additionally, we will analyze therapy by argon plasma coagulation and radiofrequency ablation. Furthermore, outcome in curative and palliative interventions can be distinguished. Conclusion: The ESAP study will provide evidence for therapeutic algorithms and data for the implementation of guidelines in the treatment of different types of ampullary tumors, including recurrent, or incomplete resected lesions.

Adaptive Optimal Control Using Frequency Selective Information of the System Uncertainty With Application to Unmanned Aircraft.

A new efficient adaptive optimal control approach is presented in this paper based on the indirect model reference adaptive control (MRAC) architecture for improvement of adaptation and tracking performance of the uncertain system. The system accounts here for both matched and unmatched unknown uncertainties that can act as plant as well as input effectiveness failures or damages. For adaptation of the unknown parameters of these uncertainties, the frequency selective learning approach is used. Its idea is to compute a filtered expression of the system uncertainty using multiple filters based on online instantaneous information, which is used for augmentation of the update law. It is capable of adjusting a sudden change in system dynamics without depending on high adaptation gains and can satisfy exponential parameter error convergence under certain conditions in the presence of structured matched and unmatched uncertainties as well. Additionally, the controller of the MRAC system is designed using a new optimal control method. This method is a new linear quadratic regulator-based optimal control formulation for both output regulation and command tracking problems. It provides a closed-form control solution. The proposed overall approach is applied in a control of lateral dynamics of an unmanned aircraft problem to show its effectiveness.

On-chip PCR amplification of very long templates using immobilized primers on glassy surfaces.

In this paper we describe a novel method for visualizing very long DNA fragments (for example >6 kb) which are difficult to spot with commonly used arrayers or capillary samplers with very small nanoliter volumes, using directly bound primers on "on-chip" polymerase chain reaction (PCR). We have used the genomes of the M13 bacteriophage (7.2 kb) the human mitochondrion (16.5 kb) as examples of long DNA templates to test the PCR and were able to elicit robust reactivity. Over 75% of the immobilized primers could be elongated to their fullest extent. In addition we were able to elicit the PCR reaction with double stranded templates in which one primer was immobilized and the other suspended in the reaction solution. These synthesized PCR products were visualized by either confocal microarray scanning or fluorescence microscopy using Cy5-dye fluorescence of the modified free primer, or the fluorescence of intercalating dyes.