Comprehensive clinicopathologic characteristics of intraabdominal neurogenic tumors:Single institution experience

BACKGROUND Neurogenic tumors are rare but represent an important consideration in the differential diagnosis of abdominal mesenchymal tumors.Reports on their incidence,pathological features and clinical characteristics are scarce.AIM To advance the overall knowledge on the histologic,immunohistochemical,clinical and radiologic characteristics of neurogenic tumors through this case series.METHODS An established database of a nationwide tertiary referral center,covering a 15-year period(2005 and 2020),was retrospectively re-evaluated.Diagnoses of neurogenic tumor cases were confirmed by two experts following review of the macroscopic,histological and immunohistochemical records along with findings from analysis of archived tissue sections for each included patient.Tissue microarrays were constructed for cases lacking necessary immunohistochemical studies.Clinical data and follow-up information were collected from the hospital records and the patients themselves,when available.RESULTS The study included 19 cases of intraabdominal neurogenic tumors,representing 12 women and 7 men, between 18 and 86 years of age (median: 51 years). Finalconfirmed diagnoses were 12 schwannomas, 2 diffuse submucosal neurofibromatoses,2 ganglioneuromas, 2 malignant peripheral sheath nerve tumors,and 1 mucosal Schwann cell hamartoma. Sizes of the tumors were variable, with amedian diameter of 4 cm;the two largest (> 10 cm) were schwannomas. Themajority of cases were asymptomatic at presentation, but the most frequentsymptom was abdominal pain. Gastrointestinal tract lesions were detected withendoscopy and extra-luminal lesions were detected with cross-sectional imaging.All cases were S100-positive and CD117-negative;most cases were negative fordesmin, epithelial membrane antigen, smooth muscle actin and CD34. In all but 5cases, the Ki67 proliferation index was ≤ 1%.CONCLUSION Re-evaluation of 19 cases of abdominal neurogenic tumors demonstrated considerablevariability in clinicopathologic characteristics depending on location,dimension and histological features.

Practical points that gastrointestinal fellows should know in management of COVID-19

Pandemics obligate providers to transform their clinical practice.An extensive effort has been put to find out feasible approaches for gastrointestinal diseases and also to manage coronavirus disease 2019(COVID-19)related gastrointestinal conditions.Diarrhea,hepatitis,and pancreatitis can be seen in the COVID-19 course.Endoscopic procedures increase the risk of contamination for medical staff and patients despite precautions,therefore indications should be tailored to balance risks vs benefits.Furthermore,whether the immunosupression in inflammatory bowel diseases,liver transplantation,and autoimmune liver diseases increases COVID-19 related risks and how to modify immunosupression are topics of ongoing debate.This review aims to provide most up to date practical approaches that a gastrointestinal fellow should be aware on the problems and management of gastrointestinal and hepatobiliary diseases during the COVID-19 pandemic.

Role of gastrointestinal system on transmission and pathogenesis of SARS-CoV-2

Coronavirus disease 2019(COVID-19)continues to pose a significant threat to global health.Primary prevention remains as a major strategy against the pandemic.Current evidence proves that aerosol and droplet-based routes are the main means of transmission of COVID-19 but other ways should be sought in order to prevent possible collateral transmission.The gastrointestinal system may be one such route.Angiotensin converting enzyme 2 is the target entry receptor for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)that is abundantly expressed in the gastrointestinal tract.SARS-CoV-2 is able to infect human enterocytes similar to severe acute respiratory syndrome and Middle Eastern respiratory syndrome.Herein this review,we discuss the current knowledge regarding the role of gastrointestinal transmission in transmission and pathophysiology of COVID-19.

Machine learning in endoscopic ultrasonography and the pancreas:The new frontier?

Pancreatic diseases have a substantial burden on society which is predicted to increase further over the next decades.Endoscopic ultrasonography(EUS)remains the best available diagnostic method to assess the pancreas,however,there remains room for improvement.Artificial intelligence(AI)approaches have been adopted to assess pancreatic diseases for over a decade,but this methodology has recently reached a new era with the innovative machine learning algorithms which can process,recognize,and label endosonographic images.Our review provides a targeted summary of AI in EUS for pancreatic diseases.Included studies cover a wide spectrum of pancreatic diseases from pancreatic cystic lesions to pancreatic masses and diagnosis of pancreatic cancer,chronic pancreatitis,and autoimmune pancreatitis.For these,AI models seemed highly successful,although the results should be evaluated carefully as the tasks,datasets and models were greatly heterogenous.In addition to use in diagnostics,AI was also tested as a procedural real-time assistant for EUS-guided biopsy as well as recognition of standard pancreatic stations and labeling anatomical landmarks during routine examination.Studies thus far have suggested that the adoption of AI in pancreatic EUS is highly promising and further opportunities should be explored in the field.

Hepatocellular Carcinoma and the Role of Liver Transplantation:A Review

Hepatocellular carcinoma(HCC)is one of the leading causes of cancer deaths worldwide and liver transplantation(LT)is the only potentially curative treatment.Over the years,Milan criteria has been used for patient selection.There is ongoing research in this field with introduction of new biomarkers for HCC that can help guide future treatment.Furthermore,newer therapies for downstaging of the tumor are being implemented to prevent dropout from the transplant list.In addition,combination therapies for better outcome are under investigation.Interestingly,the concept of living-donor LT and possible use of hepatitis C virus-positive donors has been implemented as an attempt to expand the organ pool.However,there is a conflict of opinion between different centers regarding its efficacy and data is scarce.The aim of this review article is to outline the various selection criteria for LT,discuss the outcomes of LT in HCC patients,and explore future directions of LT for HCC.Therefore,a comprehensive PubMed/MEDLINE review was conducted.To expand our search,references of the retrieved articles were also screened for additional data.After selecting the studies,the authors independently reviewed them to identify the relevant studies.After careful evaluation 120 studies relevant to out topic are cited in the manuscript.Three tables and two figures are also included.In conclusion LT for HCC has evolved over the years.With the introduction of several expanded criteria beyond Milan,the introduction of bridging therapies,such as transcatheter arterial chemoembolization and radiofrequency ablation,and the approval of newer systemic therapies,it is evident that there will be more LT recipients in the future.It is promising to see ongoing trials and the continuous evolution of protocols.Prospective studies are needed to guide the development of a pre-LT criteria that can ensure low HCC recurrence risk and is not overly stringent,clarify the role of LDLT,and determine the optimal bridging therapies to LT.

Recurrence of hepatocellular carcinoma following deceased donor liver transplantation:case series

Aim:We aimed to study the clinical and pathological characteristics of liver transplant recipients with hepatocellular carcinoma recurrence.Methods:We reviewed the data for 26 patients who had tumor recurrence after deceased donor liver transplant for hepatocellular carcinoma at the Johns Hopkins Hospital from January 2005 to December 2015.Results:In total,88%of recipients were males.The mean age was 59 years.On explant,poor differentiation was detected in 43%,while 73%had microvascular invasion.Overall,62%were diagnosed to be outside of Milan criteria.Out of these,15%met the criteria for downstaging.Twenty(77%)patients had pre-transplant alpha fetoprotein levels≥20 ng/mL.In 54%of patients,the location of hepatocellular carcinoma(HCC)recurrence was extrahepatic,followed by intrahepatic in 31%and both intra-and extrahepatic in 15%.The post-transplant tumor recurrence was diagnosed at a mean of 427 days(range 34-1502).Fifty percent of HCC recurrences were diagnosed within one year following liver transplant.Twenty(77%)patients received treatment for their recurrent HCC:external radiation(n=10),surgical resections(n=8;brain 4,spine 2,bone 1,and Whipple surgery 1),sorafenib(n=7),locoregional therapy(n=5).Overall,24 out of 26(92%)recipients died within four years after the transplant.Conclusion:HCC recurrence after liver transplant is infrequent.More than fifty percent of HCC recurrences following liver transplant are extrahepatic.Despite better recipient selection for liver transplant,the curative options are limited in recurrent cases and associated with extremely poor outcomes.