We discuss an experiment to investigate neutrino physics at the LHC, with emphasis on tau flavour. As described in our previous paper Beni et al (2019 J. Phys. G: Nucl. Part. Phys. 46 115008), the ...detector can be installed in the decommissioned TI18 tunnel, ≈480 m downstream the ATLAS cavern, after the first bending dipoles of the LHC arc. The detector intercepts the intense neutrino flux, generated by the LHC beams colliding in IP1, at large pseudorapidity η, where neutrino energies can exceed a TeV. This paper focuses on exploring the neutrino pseudorapity versus energy phase space available in TI18 in order to optimize the detector location and acceptance for neutrinos originating at the pp interaction point, in contrast to neutrinos from pion and kaon decays. The studies are based on the comparison of simulated pp collisions at s= 13 TeV: PYTHIA events of heavy quark (c and b) production, compared to DPMJET minimum bias events (including charm) with produced particles traced through realistic LHC optics with FLUKA. Our studies favour a configuration where the detector is positioned off the beam axis, slightly above the ideal prolongation of the LHC beam from the straight section, covering 7.4 < η < 9.2. In this configuration, the flux at high energies (0.5-1.5 TeV and beyond) is found to be dominated by neutrinos originating directly from IP1, mostly from charm decays, of which ≈50% are electron neutrinos and ≈5% are tau neutrinos. The contribution of pion and kaon decays to the muon neutrino flux is found small at those high energies. With 150 fb−1 of delivered LHC luminosity in Run 3 the experiment can record a few thousand very high energy neutrino charged current (CC) interactions and over 50 tau neutrino CC events. These events provide useful information in view of a high statistics experiment at HL-LHC. The electron and muon neutrino samples can extend the knowledge of the charm PDF to a new region of x, which is dominated by theory uncertainties. The tau neutrino sample can provide first experience on reconstruction of tau neutrino events in a very boosted regime.
This paper summarises and discusses the results of a preliminary damage assessment of the non-seizure coating of the bayonet IFMIF back-plate. Neutron-induced kerma factors, dpa and gas production ...cross sections libraries were produced in a multigroup structure for neutron energies up to 60
MeV, by processing evaluated nuclear data files with NJOY-99.259 system. The material damage evaluations in terms of heat deposition, displacement and gas production rates were calculated using these libraries and compared with the values obtained using the data contained in the pointwise ACE format files of MCNP5 code package. The calculations were performed with MCNP5 code both using the McEnea and the McDelicious neutron source models to reproduce the energy-angle distributions of the neutrons produced in IFMIF d-Li interactions.
Background and Aims The American Gastroenterological Association (AGA) recently reported evidence-based guidelines for the management of asymptomatic neoplastic pancreatic cysts. These guidelines ...advocate a higher threshold for surgical resection than prior guidelines and imaging surveillance for a considerable number of patients with pancreatic cysts. The aims of this study were to assess the accuracy of the AGA guidelines in detecting advanced neoplasia and present an alternative approach to pancreatic cysts. Methods The study population consisted of 225 patients who underwent EUS-guided FNA for pancreatic cysts between January 2014 and May 2015. For each patient, clinical findings, EUS features, cytopathology results, carcinoembryonic antigen analysis, and molecular testing of pancreatic cyst fluid were reviewed. Molecular testing included the assessment of hotspot mutations and deletions for KRAS , GNAS , VHL , TP53 , PIK3CA, and PTEN. Results Diagnostic pathology results were available for 41 patients (18%), with 13 (6%) harboring advanced neoplasia. Among these cases, the AGA guidelines identified advanced neoplasia with 62% sensitivity, 79% specificity, 57% positive predictive value, and 82% negative predictive value. Moreover, the AGA guidelines missed 45% of intraductal papillary mucinous neoplasms with adenocarcinoma or high-grade dysplasia. For cases without confirmatory pathology, 27 of 184 patients (15%) with serous cystadenomas (SCAs) based on EUS findings and/or VHL alterations would continue magnetic resonance imaging (MRI) surveillance. In comparison, a novel algorithmic pathway using molecular testing of pancreatic cyst fluid detected advanced neoplasias with 100% sensitivity, 90% specificity, 79% positive predictive value, and 100% negative predictive value. Conclusions The AGA guidelines were inaccurate in detecting pancreatic cysts with advanced neoplasia. Furthermore, because the AGA guidelines manage all neoplastic cysts similarly, patients with SCAs will continue to undergo unnecessary MRI surveillance. The results of an alternative approach with integrative molecular testing are encouraging but require further validation.
Background Stereotactic body radiotherapy (SBRT) has been approved for the treatment of locally advanced pancreatic cancer. Placement of gold fiducials is required for real-time tracking and delivery ...of a high-dose therapeutic beam of radiation to the tumor. Traditionally, fiducials have been placed either intraoperatively or percutaneously. Recently, EUS-guided fiducial placement has been reported, but the safety and feasibility of this approach is not well defined. Objective The aim of this study was to determine the safety, feasibility, and limitations of EUS-guided placement of 0.8 × 5.0 mm fiducials via a 19-gauge needle for locally advanced and recurrent pancreatic cancer. Design Prospective study of patients with either locally advanced or recurrent pancreatic cancer referred for EUS-guided fiducial placement for SBRT at our institution over a 3-year period. Setting Tertiary referral center conducting >1800 EUS procedures annually. Main Outcome Measurements Primary outcome measurements included success, complications, and technical limitations of EUS-guided fiducial placement in pancreatic cancer. In addition, the percentage of patients successfully completing SBRT after EUS-guided fiducial placement was determined. Results A total of 51 patients (mean age 73 years; 57% male) with locally advanced (n = 36) and recurrent (n = 15) pancreatic cancer were referred for EUS-guided fiducial placement. Fiducials were successfully placed in 46 patients (90%), with technical failures occurring in 4 patients (8%) with recurrent cancer after pancreaticoduodenectomy. In 3 patients (7%), the fiducials spontaneously migrated from the original site of injection, thereby requiring a second EUS procedure for placement of additional fiducials. Of the 46 patients with fiducials placed under EUS guidance, 42 patients (91%) successfully completed SBRT. Two patients experienced disease progression before SBRT, 1 patient was lost to follow-up, and 1 patient experienced a complication at ERCP that precluded further therapy. Only 1 complication (2%), of mild pancreatitis, occurred in a patient undergoing simultaneous placement of fiducials and celiac plexus neurolysis for intractable abdominal pain. Limitations Single-center experience and lack of a formal follow-up protocol to assess for complications. Conclusion EUS-guided fiducial placement for SBRT in locally advanced and recurrent pancreatic cancer is safe and feasible. Successful placement was achieved in 90% of patients, with a low complication rate (2%). Furthermore, 91% of patients successfully completed SBRT after EUS-guided fiducial delivery. Although fiducials can spontaneously migrate from the initial injection site, the rate of migration is relatively low (7%), and no migration-related complications occurred over the course of this study. Limitations to EUS-guided fiducial placement may include surgically altered anatomy (pancreaticoduodenectomy) in patients with recurrent pancreatic cancer.
Pancreatic cystic lesions are being detected more frequently given increased use of cross-sectional imaging modalities. The most common cysts encountered are mucinous cysts, which have malignant ...potential. As many of these lesions are incidental findings, it is important to further evaluate them with endoscopic ultrasound-guided fine needle aspiration for diagnostic purposes and risk stratification. These cysts either require surgical resection or surveillance given the malignant risk. Mucinous cystic neoplasms should be resected. Intraductal papillary mucinous neoplasia (IPMN) has consensus-guideline indications for resection. These include main duct diameter ≥ 10 mm, a branch duct size ≥ 3 cm, presence of a mural nodule, or cytology suspicious for malignancy. Additionally, all symptomatic cysts, regardless of etiology, should undergo resection. Branch duct IPMN is less aggressive that the main duct variety, and may be conservatively followed. However, the development of an established indication for resection should prompt surgery. Despite generalized guidelines, decisions regarding management of pancreatic cysts should be individualized, accounting for the malignant risk of the lesion and the surgical risk of the patient.
Background EMR and ablation are increasingly being used alone or in combination for treatment of Barrett's neoplasia. Given a very low rate of lymph node metastasis, endotherapy has become an ...accepted treatment option for T1a esophageal adenocarcinoma (EAC) with low-risk features. Objective To report our experience of endoscopic management of T1a EAC in a large, tertiary-care center. Design Retrospective review. Setting Tertiary-care referral center. Patients Patients treated endoscopically for low-risk T1a EAC at our center. Intervention EMR and endoscopic ablation. Main Outcome Measurements Death related to esophageal cancer, remission of adenocarcinoma, dysplasia, and intestinal metaplasia. Results A total of 54 patients underwent endotherapy for low-risk T1a EAC from 2006 to 2012. Mean (± SD) follow-up was 23 (± 16) months, mean (± SD) size of resected adenocarcinoma was 7.1 (± 4.3) mm, and mean (± SD) Barrett's esophagus length was 4.5 (± 3.9) cm. Band-assisted, cap-assisted, and lift and cut EMR were performed in 85%, 11%, and 4% of patients, respectively; 81% underwent additional ablative therapy (radiofrequency ablation 95%, cryotherapy 9%, photodynamic therapy 2%). Complete remission from cancer was achieved in 96%, complete remission from dysplasia in 87%, and complete remission from intestinal metaplasia in 59%. The overall survival was 89%; there were no deaths related to esophageal cancer. Limitations Retrospective study. Conclusion Endotherapy for T1a EAC was safe and effective in our American cohort. Endotherapy should be considered primary therapy for appropriate patients with low-risk lesions. Complete Barrett's esophagus eradication after EMR is important to reduce the development of metachronous lesions.
Background Lymphoepithelial cysts (LEC) of the pancreas are rare benign lesions that can be misdiagnosed as pancreatic masses or cystic neoplasms. With widespread use of abdominal cross-sectional ...imaging, more pancreatic lesions are being discovered, with EUS being used to further evaluate the abnormality. Objective Our purpose was to describe EUS and cyst aspirate features of LEC of the pancreas. Design Case series. Setting Single tertiary referral center. Patients Nine patients with lymphoepithelial cysts who underwent EUS-FNA. Results Five male and 4 female patients were identified (mean age 51 years). All lesions were discovered by CT and described as “peripancreatic” in 67% of cases (6/9). EUS examination described a solid-appearing hypoechoic and heterogeneous mass with subtle postacoustic enhancement in 5 of 9 cases. Four lesions were described as purely cystic: 2 were septated, 1 was unilocular, and 1 had internal papillary fronds. Mean cyst size was 5.2 cm (range 1.7-12 cm). Cyst aspirates revealed a thick milky, creamy, or frothy aspirate in 56% of cases (5/9). Cyst cytologic examination revealed squamous material (nucleated/anucleated cells or keratin debris) in all cases. Lymphocytes were seen in 56% of aspirates (5/9). Carcinoembryonic antigen (CEA) levels were obtained in 5 cases (median 6.5 ng/mL range 2.9-493.4 ng/mL). Six patients have avoided surgery on the basis of EUS-FNA cytologic results confirming the diagnosis of LEC. Three patients underwent surgical resection: 2 for symptomatic lesions and 1 for concern for a mucinous cystic neoplasm given an elevated aspirate CEA level. Surgical pathologic examination confirmed LEC in each. Limitations Retrospective single-center study. Conclusions LEC should be considered whenever a large, well-defined solid or cystic peripheral pancreatic lesion is found. A thick milky, creamy, or frothy aspirate is common. The presence of squamous material and lymphocytes on cytologic examination is diagnostic of LEC. Aspirate CEA level may be elevated and should be considered in conjunction with cytologic results to avoid misdiagnosis as a mucinous cystic neoplasm. Asymptomatic LEC should be managed conservatively.
Chronic, debilitating abdominal pain is arguably the most important component of chronic pancreatitis, leading to significant morbidity and disability. Attempting to treat this pain, which is too ...often unsuccessful, is a frustrating experience for physician and patient. Multiple studies to improve understanding of the pathophysiology that causes pain in some patients but not in others have been performed since the most recent reviews on this topic. In addition, new treatment modalities have been developed and evaluated in this population. This review discusses new advances in neuroscience and the study of visceral pain mechanisms, as well as genetic factors that may play a role. Updates of established therapies, as well as new techniques used in addressing pain from chronic pancreatitis, are reviewed. Lastly, outcome measures, which have been highly variable in this field over the years, are addressed.
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