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Dive into the research topics where Schuyler O. Sanderson is active.

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Featured researches published by Schuyler O. Sanderson.


Hepatology | 2007

The NAFLD fibrosis score: a noninvasive system that identifies liver fibrosis in patients with NAFLD.

Paul Angulo; Jason M. Hui; Giulio Marchesini; Ellisabetta Bugianesi; Jacob George; Geoffrey C. Farrell; Felicity Enders; Sushma Saksena; Alastair D. Burt; John P. Bida; Keith D. Lindor; Schuyler O. Sanderson; Marco Lenzi; Leon A. Adams; James G. Kench; Terry M. Therneau; Christopher P. Day

Patients with nonalcoholic fatty liver disease (NAFLD) and advanced liver fibrosis are at the highest risk for progressing to end‐stage liver disease. We constructed and validated a scoring system consisting of routinely measured and readily available clinical and laboratory data to separate NAFLD patients with and without advanced fibrosis. A total of 733 patients with NAFLD confirmed by liver biopsy were divided into 2 groups to construct (n = 480) and validate (n = 253) a scoring system. Routine demographic, clinical, and laboratory variables were analyzed by multivariate modeling to predict presence or absence of advanced fibrosis. Age, hyperglycemia, body mass index, platelet count, albumin, and AST/ALT ratio were independent indicators of advanced liver fibrosis. A scoring system with these 6 variables had an area under the receiver operating characteristic curve of 0.88 and 0.82 in the estimation and validation groups, respectively. By applying the low cutoff score (−1.455), advanced fibrosis could be excluded with high accuracy (negative predictive value of 93% and 88% in the estimation and validation groups, respectively). By applying the high cutoff score (0.676), the presence of advanced fibrosis could be diagnosed with high accuracy (positive predictive value of 90% and 82% in the estimation and validation groups, respectively). By applying this model, a liver biopsy would have been avoided in 549 (75%) of the 733 patients, with correct prediction in 496 (90%). Conclusion: a simple scoring system accurately separates patients with NAFLD with and without advanced fibrosis, rendering liver biopsy for identification of advanced fibrosis unnecessary in a substantial proportion of patients. (HEPATOLOGY 2007;45:846–854.)


Hepatology | 2007

Magnetic resonance imaging of hepatic fibrosis: Emerging clinical applications†

Jayant A. Talwalkar; Meng Yin; Jeff L. Fidler; Schuyler O. Sanderson; Patrick S. Kamath; Richard L. Ehman

Chronic liver disease and cirrhosis remains a major public health problem worldwide. While the majority of complications from chronic liver disease result from progressive hepatic fibrosis, the available diagnostic tests used in clinical practice are not sensitive or specific enough to detect occult liver injury at early or intermediate stages. While liver biopsy can stage the extent of fibrosis at diagnosis, its utility as a tool for longitudinal monitoring will be limited at the population level. To date, a number of methods including serum marker panels and ultrasound‐based transient elastrography have been proposed for the non‐invasive identification of hepatic fibrosis. Novel techniques including magnetic resonance (MR) spectroscopy, diffusion weighted MR, and MR elastography have also emerged for detecting fibrosis. In contrast to other non‐invasive methods, MR imaging holds the promise of providing functional and biological information about hepatic pathophysiology as it relates to the natural history and future treatment of hepatic fibrosis. (HEPATOLOGY 2007.)


Radiology | 2011

Early detection of nonalcoholic steatohepatitis in patients with nonalcoholic fatty liver disease by using MR elastography

Jun Chen; Jayant A. Talwalkar; Meng Yin; Kevin J. Glaser; Schuyler O. Sanderson; Richard L. Ehman

PURPOSE To investigate the diagnostic accuracy (area under the receiver operating characteristic curve [AUROC]) of magnetic resonance (MR) elastography for the early detection of nonalcoholic steatohepatitis (NASH) among patients with nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS An institutional review board-approved and HIPAA-compliant retrospective study was conducted in 58 NAFLD patients. Informed consent was waived by the review board. Hepatic stiffness, relative fat fraction, inflammation grade, and fibrosis stage were assessed from MR elastography, in-phase and out-of-phase gradient-echo imaging, and liver biopsy histopathologic review, respectively. Pairwise t testing, receiver operating characteristic analysis, and partial correlation analysis were performed. RESULTS The mean hepatic stiffness for patients with simple steatosis (2.51 kPa) was less (P = .028) than that for patients with inflammation but no fibrosis (3.24 kPa). The mean hepatic stiffness for patients with inflammation but no fibrosis was less (P = .030) than that for patients with hepatic fibrosis (4.16 kPa). Liver stiffness had high accuracy (AUROC = 0.93) for discriminating patients with NASH from those with simple steatosis, with a sensitivity of 94% and a specificity 73% by using a threshold of 2.74 kPa. CONCLUSION In patients with NAFLD, hepatic stiffness measurements with MR elastography can help identify individuals with steatohepatitis, even before the onset of fibrosis; NAFLD patients with inflammation but no fibrosis have greater liver stiffness than those with simple steatosis and lower mean stiffness than those with fibrosis.


Hepatology | 2010

Drug-induced autoimmune hepatitis: clinical characteristics and prognosis.

Einar Björnsson; Jayant A. Talwalkar; Sombat Treeprasertsuk; Patrick S. Kamath; Naoki Takahashi; Schuyler O. Sanderson; Matthias Neuhauser; Keith D. Lindor

Drug‐induced autoimmune hepatitis (DIAIH) has been reported to be caused by several drugs. There is a lack of data comparing these patients with other patients with autoimmune hepatitis (AIH). A search was performed using the Mayo Clinic diagnostic medical index for AIH patients and DIAIH patients identified over 10 years. Individuals with overlap syndromes and decompensated liver disease were excluded. Overall, 261 patients (204 females, median age 52) were identified, and 24 (9.2%) were DIAIH cases with a median age of 53 (interquartile range, 24‐61). Two drugs, nitrofurantoin (n = 11) and minocycline (n = 11), were the main causes. A similar proportion of DIAIH patients had positive antinuclear antibodies (83% versus 70%) and smooth muscle antibodies (50% versus 45%) as compared with AIH patients. Histological grade and stage were similar in patients with DIAIH versus AIH; however, none of the DIAIH patients had cirrhosis at baseline; this was present in 20% of matched AIH cases. Liver imaging was normal in all minocycline cases. Eight of 11 (73%) nitrofurantoin patients had abnormalities on hepatic imaging (mainly liver atrophy), a finding seen in only 8 of 33 (24%) of a random sample of the rest of the AIH group (P = 0.0089). Corticosteroid responsiveness was similar in DIAIH and the AIH patients. Discontinuation of immunosuppression was tried and successful in 14 DIAIH cases, with no relapses (0%), whereas 65% of the AIH patients had a relapse after discontinuation of immunosuppression (P < 0.0001). Conclusion: A significant proportion of patients with AIH have drug‐induced AIH, mainly because of nitrofurantoin and minocycline. These two groups have similar clinical and histological patterns. However, DIAIH patients do not seem to require long‐term immunosuppressive therapy. (HEPATOLOGY 2010;)


Hepatology | 2009

Betaine for nonalcoholic fatty liver disease: Results of a randomized placebo‐controlled trial

Manal F. Abdelmalek; Schuyler O. Sanderson; Paul Angulo; Consuelo Soldevila-Pico; Chen Liu; Joy Peter; Jill Keach; Matt Cave; Theresa Chen; Craig J. McClain; Keith D. Lindor

Based on animal studies and pilot studies in humans, betaine, a methyl donor for the remethylation of homocysteine, may be a therapeutic agent for nonalcoholic steatohepatitis (NASH). We evaluated the safety and efficacy of betaine for patients with NASH and whether betaine positively modified factors postulated to be “second hits” and underlying mechanisms of NASH. We conducted a randomized placebo‐control study of 55 patients with biopsy‐proven NASH who received either oral betaine (20 g daily) or placebo for 12 months. Pre‐ and posttreatment variables were analyzed using the paired t test or Wilcoxon rank test. Treatment groups were comparable at baseline. Of the 35 patients (17 betaine, 18 placebo) who completed the study, 34 patients (16 betaine, 18 placebo) underwent posttreatment liver biopsy. Patients randomized to betaine had a decrease in steatosis grade. No intra‐ or intergroup differences or changes in nonalcoholic fatty liver disease activity score or fibrosis stage were noted. Elevations of insulin, glucose, and proinflammatory cytokines and the reduced antioxidant status noted in NASH patients did not improve with betaine therapy. The antiinflammatory agent adiponectin was significantly reduced in both groups and did not change with therapy. Lastly, S‐adenosylhomocysteine was approximately twice normal and was not reduced by betaine therapy. Conclusion: Compared to placebo, betaine improved hepatic steatosis and may protect against worsening steatosis. High‐dose betaine supplementation failed to reduce S‐adenosylhomocysteine and did not positively affect any of the second hit mechanisms postulated to contribute to NASH that we studied. Although betaine has been proven effective in treating hepatic steatosis in several animal models, translating novel therapeutic options noted in animal studies to humans with NASH will prove challenging. (HEPATOLOGY 2009.)


Hepatology | 2008

Sulfatase 2 up-regulates glypican 3, promotes fibroblast growth factor signaling, and decreases survival in hepatocellular carcinoma.

Jin Ping Lai; Dalbir S. Sandhu; Chunrong Yu; Tao Han; Catherine D. Moser; Kenard K. Jackson; Ruben Bonilla Guerrero; Ileana Aderca; Hajime Isomoto; Megan M. Garrity-Park; Hongzhi Zou; Abdirashid M. Shire; David M. Nagorney; Schuyler O. Sanderson; Alex A. Adjei; Ju Seog Lee; Snorri S. Thorgeirsson; Lewis R. Roberts

It has been shown that the heparin‐degrading endosulfatase, sulfatase 1 (SULF1), functions as a liver tumor suppressor, but the role of the related sulfatase, sulfatase 2 (SULF2), in liver carcinogenesis remains to be elucidated. We investigated the effect of SULF2 on liver tumorigenesis. Expression of SULF2 was increased in 79 (57%) of 139 hepatocellular carcinomas (HCCs) and 8 (73%) of 11 HCC cell lines. Forced expression of SULF2 increased HCC cell growth and migration, whereas knockdown of SULF2 using short hairpin RNA targeting SULF2 abrogated HCC cell proliferation and migration in vitro. Because SULF1 and SULF2 desulfate heparan sulfate proteoglycans (HSPGs) and the HSPG glypican 3 (GPC3) is up‐regulated in HCC, we investigated the effects of SULF2 on GPC3 expression and the association of SULF2 with GPC3. SULF2‐mediated cell growth was associated with increased binding of fibroblast growth factor 2 (FGF2), phosphorylation of extracellular signal‐regulated kinase and AKT, and expression of GPC3. Knockdown of GPC3 attenuated FGF2 binding in SULF2‐expressing HCC cells. The effects of SULF2 on up‐regulation of GPC3 and tumor growth were confirmed in nude mouse xenografts. Moreover, HCC patients with increased SULF2 expression in resected HCC tissues had a worse prognosis and a higher rate of recurrence after surgery. Conclusion: In contrast to the tumor suppressor effect of SULF1, SULF2 has an oncogenic effect in HCC mediated in part through up‐regulation of FGF signaling and GPC3 expression. (HEPATOLOGY 2008.)


Liver Transplantation | 2006

Liver transplantation for gastroenteropancreatic neuroendocrine cancers: Defining selection criteria to improve survival

Frederike G.I. van Vilsteren; Edwina S. Baskin-Bey; David M. Nagorney; Schuyler O. Sanderson; Walter K. Kremers; Charles B. Rosen; Gregory J. Gores; Timothy J. Hobday

Liver transplantation for gastroenteropancreatic neuroendocrine cancer (GEP) is controversial. The aim of this study was to assess patient outcomes after liver transplantation for hepatic metastases from GEP. Medical records of patients who underwent liver transplantation for GEP were reviewed. Immunohistochemistry for assessing the Ki67 proliferation index was performed on explanted liver tissue. Nineteen patients who underwent liver transplantation had a mean follow‐up of 22 months with a range of 0 to 84 months. There was 1 intraoperative death, and 3 patients had disease recurrence after liver transplantation leading to death in 1 patient. Overall estimated 1‐year survival for 17 patients included in the treatment protocol (mean follow‐up, 15 months) was 87% with an estimated 1‐year recurrence‐free rate (conditional on survival) of 77%. Three of 11 patients with pancreatic islet cell GEP developed disease recurrence, whereas all 8 patients with carcinoid GEP remain free of disease. Analysis of the Ki67 proliferation index in 18 patients did not differentiate those with recurrence from those without disease recurrence. In conclusion, liver transplantation for patients with hepatic metastases from GEP is a viable therapeutic option in highly selected patients. Liver Transpl 12:448–456, 2006.


Clinical Gastroenterology and Hepatology | 2011

Cirrhosis Is Present in Most Patients With Hepatitis B and Hepatocellular Carcinoma

Ju Dong Yang; W. Ray Kim; Ritika Coelho; Teresa A. Mettler; Joanne T. Benson; Schuyler O. Sanderson; Terry M. Therneau; Bohyun Kim; Lewis R. Roberts

BACKGROUND & AIMS There are few data available about the prevalence or effects of cirrhosis in patients with hepatocellular carcinoma (HCC) from viral hepatitis. We compared patients with HCC and hepatitis B virus (HBV) or hepatitis C virus (HCV) infections to determine the proportions of cirrhosis in each group, virologic and tumor characteristics, and overall survival. METHODS This analysis included patients with HBV (n = 64) or HCV (n = 118) infection who were diagnosed with HCC at the Mayo Clinic in Rochester, Minnesota from 1994-2008; groups were matched for age and sex. The diagnosis of cirrhosis was based on histology and, if histologic information was insufficient or unavailable, clinical indicators that included ascites or varices, thrombocytopenia or splenomegaly, and radiographic configuration of cirrhosis. Virologic characteristics, tumor stage, and patient survival were also assessed. RESULTS The prevalence of histologic cirrhosis was 88% among patients with HBV infection and 93% among those with HCV infection (P = .46). When the most inclusive criteria for cirrhosis were applied, cirrhosis was present in 94% of patients with HBV and 97% with HCV (P = .24). Among HCV patients, 5.2% were negative for HCV RNA after antiviral treatment; 63.4% of HBV patients had HBV DNA <2000 IU/mL with or without treatment. Patients with HBV tended to have less surveillance and more advanced stages of HCC, without differences in survival from those with HCV infection (P = .75). CONCLUSIONS Most patients with HCC and chronic viral hepatitis had evidence of cirrhosis, including those with HBV infection and those without active viral replication.


Mayo Clinic Proceedings | 2006

Metastatic Malignant Melanoma of the Gastrointestinal Tract

Kelly V. Liang; Schuyler O. Sanderson; Grzegorz S. Nowakowski; Amindra S. Arora

Malignant melanoma is one of the most common malignancies to metastasize to the gastrointestinal (GI) tract. Metastases to the GI tract can present at the time of primary diagnosis or decades later as the first sign of recurrence. Symptoms may include abdominal pain, dysphagia, small bowel obstruction, hematemesis, and melena. We report 2 cases of malignant melanoma metastatic to the GI tract, followed by a review of the literature. The first case is a 72-year-old man who underwent resection of superficial spreading melanoma on his back 13 years previously who presented with dysphagia. A biopsy specimen of a mucosal fold in a gastric fundus noted during endoscopy was taken and revealed metastatic malignant melanoma, which was resected 1 month later. Three weeks later, the patient was found to have an ulcerated jejunal metastatic melanoma mass, which was also resected. The second case is a 63-year-old man with an ocular melanoma involving the chorold of the left eye that had been diagnosed 4 years previously, which had been excised several times, who presented with anorexia, dizziness, and fatigue. He was found to have cerebellar and stomach metastases. He underwent adjuvant radiation therapy, chemotherapy, and surgical resection of the gastric melanoma metastasis. In patients with a history of melanoma, a high index of suspicion for metastasis must be maintained if they present with seemingly unrelated symptoms. Diagnosis requires careful inspection of the mucosa for metastatic lesions and biopsy with special immunohistochemical stains. Management may include surgical resection, chemotherapy, immunotherapy, observation, or enrollment in clinical trials. Prognosis is poor, with a median survival of 4 to 6 months.


Radiology | 2013

Assessment of Liver Viscoelasticity by Using Shear Waves Induced by Ultrasound Radiation Force

Shigao Chen; William Sanchez; Matthew R. Callstrom; Brian Gorman; Jason T. Lewis; Schuyler O. Sanderson; James F. Greenleaf; Hua Xie; Yan Shi; Michael D. Pashley; Vijay Shamdasani; Michael Lachman; Stephen Metz

PURPOSE To investigate the value of viscosity measured with ultrasonographic (US) elastography in liver fibrosis staging and to determine whether the use of a viscoelastic model to estimate liver elasticity can improve its accuracy in fibrosis staging. MATERIALS AND METHODS The study, which was performed from February 2010 to March 2011, was compliant with HIPAA and approved by the institutional review board. Written informed consent was obtained from each subject. Ten healthy volunteers (eight women and two men aged 27-55 years) and 35 patients with liver disease (17 women and 18 men aged 19-74 years) were studied by using US elasticity measurements of the liver (within 6 months of liver biopsy). US data were analyzed with the shear wave dispersion ultrasound vibrometry (SDUV) method, in which elasticity and viscosity are measured by evaluating dispersion of shear wave propagation speed, as well as with the time-to-peak (TTP) method, where tissue viscosity was neglected and only elasticity was estimated from the effective shear wave speed. The hepatic fibrosis stage was assessed histologically by using the METAVIR scoring system. The correlation of elasticity and viscosity was assessed with the Pearson correlation coefficient. The performances of SDUV and TTP were evaluated with receiver operating characteristic (ROC) curve analysis. RESULTS The authors found significant correlations between elasticity and viscosity measured with SDUV (r = 0.80) and elasticity measured with SDUV and TTP (r = 0.94). The area under the ROC curve for differentiating between grade F0-F1 fibrosis and grade F2-F4 fibrosis was 0.98 for elasticity measured with SDUV, 0.86 for viscosity measured with SDUV, and 0.95 for elasticity measured with TTP. CONCLUSION The results suggest that elasticity and viscosity measured between 95 Hz and 380 Hz by using SDUV are correlated and that elasticity measurements from SDUV and TTP showed substantially similar performance in liver fibrosis staging, although elasticity calculated from SDUV provided a better area under the ROC curve.

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Michael R. Charlton

Intermountain Medical Center

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Paul Angulo

University of Kentucky

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