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Dive into the research topics where Michael H. Chapman is active.

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Featured researches published by Michael H. Chapman.


Clinical Gastroenterology and Hepatology | 2009

Presentation and Management of Post-treatment Relapse in Autoimmune Pancreatitis/Immunoglobulin G4-Associated Cholangitis

Neomal S. Sandanayake; Nicholas I. Church; Michael H. Chapman; Gavin J. Johnson; Dipok Kumar Dhar; Zahir Amin; Maesha Deheragoda; Marco Novelli; Alison Winstanley; Manuel Rodriguez–Justo; Adrian R. Hatfield; Stephen P. Pereira; George Webster

BACKGROUND & AIMS Autoimmune pancreatitis (AIP) is a multisystem disorder that often has extrapancreatic manifestations such as immunoglobulin G4-associated cholangitis (IAC). Patients respond rapidly to steroids but can relapse after therapy. We assessed the clinical management of relapse in a group of patients with AIP/IAC. METHODS We performed a prospective study of patients diagnosed with AIP from 2004-2007 who received steroids. Treatment outcome was defined clinically, radiologically, and biochemically as response to steroids, remission after steroids, failure to wean steroids, and relapse. Steroids +/- azathioprine (AZA) were used to treat patients who failed, relapsed, or could not be weaned from steroids. RESULTS Twenty-eight patients with AIP were studied; 23 (82%) had IAC. All patients responded within 6 weeks to prednisolone therapy. Twenty-three patients achieved remission after a median of 5 months of treatment (range, 1.5-17 months), whereas 5 patients (18%) could not be weaned because of a disease flare. Of the patients who achieved remission, 8 of 23 (35%) subsequently relapsed. Overall, 13 of 23 patients (57%) with AIP/IAC relapsed, compared with 0 of the 5 with isolated AIP (P = .04, Fisher exact test). Steroids were increased/restarted in all patients who relapsed; 10 also received AZA. Remission was achieved and maintained in 7 patients; they remain on AZA monotherapy at a median of 14 months (range, 1-27 months). CONCLUSIONS Relapse or failure to wean steroids occurred in 46% of patients with AIP. Patients with IAC are at particularly high risk of relapse. AZA appears to be effective in patients with post-treatment relapse or who cannot be weaned from steroids. To view this articles video abstract, go to the AGAs YouTube Channel.


The American Journal of Gastroenterology | 2014

Type 1 autoimmune pancreatitis and IgG4-related sclerosing cholangitis is associated with extrapancreatic organ failure, malignancy, and mortality in a prospective UK cohort.

Matthew T. Huggett; Emma L. Culver; M Kumar; J M Hurst; Manuel Rodriguez-Justo; Michael H. Chapman; Gavin J. Johnson; Stephen P. Pereira; Roger W. Chapman; George Webster; Eleanor Barnes

OBJECTIVES:Type I autoimmune pancreatitis (AIP) and IgG4-related sclerosing cholangitis (IgG4-related SC) are now recognized as components of a multisystem IgG4-related disease (IgG4-RD). We aimed to define the clinical course and long-term outcomes in patients with AIP/IgG4-SC recruited from two large UK tertiary referral centers.METHODS:Data were collected from 115 patients identified between 2004 and 2013, and all were followed up prospectively from diagnosis for a median of 33 months (range 1–107), and evaluated for response to therapy, the development of multiorgan involvement, and malignancy. Comparisons were made with national UK statistics.RESULTS:Although there was an initial response to steroids in 97%, relapse occurred in 50% of patients. IgG4-SC was an important predictor of relapse (P<0.01). Malignancy occurred in 11% shortly before or after the diagnosis of IgG4-RD, including three hepatopancreaticobiliary cancers. The risk of any cancer at diagnosis or during follow-up when compared with matched national statistics was increased (odds ratio=2.25, CI=1.12–3.94, P=0.02). Organ dysfunction occurred within the pancreas, liver, kidney, lung, and brain. Mortality occurred in 10% of patients during follow-up. The risk of death was increased compared with matched national statistics (odds ratio=2.07, CI=1.07–3.55, P=0.02).CONCLUSIONS:Our findings suggest that AIP and IgG4-SC are associated with significant morbidity and mortality owing to extrapancreatic organ failure and malignancy. Detailed clinical evaluation for evidence of organ dysfunction and associated malignancy is required both at first presentation and during long-term follow-up.


Alimentary Pharmacology & Therapeutics | 2003

Sandostatin LAR (long-acting octreotide acetate) for malignant carcinoid syndrome: a 3-year experience

J. Garland; J. R. Buscombe; C. Bouvier; P. Bouloux; Michael H. Chapman; A. C. Chow; N. Reynolds; Martyn Caplin

Background : Somatostatin analogues are the best therapy for controlling the symptoms of malignant carcinoid syndrome. Octreotide acetate given as subcutaneous injection up to three times daily, intramuscular Lanreotide injection given once per 1–2 weeks and monthly intramuscular Sandostatin LAR have demonstrated similar efficacy in short‐term studies.


European Journal of Gastroenterology & Hepatology | 2012

Cholangiocarcinoma and dominant strictures in patients with primary sclerosing cholangitis: a 25-year single-centre experience.

Michael H. Chapman; George Webster; Selina Bannoo; Gavin J. Johnson; Johannes Wittmann; Stephen P. Pereira

Background Dominant biliary strictures occur commonly in patients with primary sclerosing cholangitis (PSC), who have a high risk of developing cholangiocarcinoma (CC). The natural history and optimal management of dominant strictures remain unclear, with some reports suggesting that endoscopic interventions improve outcome. Methods We describe a 25-year experience in patients with PSC-related dominant strictures at a single tertiary referral centre. Results A total of 128 patients with PSC (64% men, mean age at referral 49 years) were followed for a mean of 9.8 years. Eighty patients (62.5%) with dominant biliary strictures had a median of 3 (range 0–34) interventions, compared with 0 (0–7) in the 48 patients without dominant strictures (P<0.001). Endoscopic interventions included the following: (i) stenting alone (46%), (ii) dilatation alone (20%), (iii) dilatation and stenting (17%) and (iv) none or failed intervention (17%, of whom most required percutaneous transhepatic drainage). The major complication rate for endoscopic retrograde cholangiopancreatography was low (1%). The mean survival of those with dominant strictures (13.7 years) was worse than that for those without dominant strictures (23 years), with much of the survival difference related to a 26% risk of CC developing only in those with dominant strictures. Half of those with CC presented within 4 months of the diagnosis of PSC, highlighting the importance of a thorough evaluation of new dominant strictures. Conclusion Repeated endoscopic therapy in PSC patients is safe, but the prognosis remains worse in the subgroup with dominant strictures. In our series, dominant strictures were associated with a high risk of developing CC.


Clinical Gastroenterology and Hepatology | 2011

Endoscopic Retrograde Cholangiography Does Not Reliably Distinguish IgG4-Associated Cholangitis From Primary Sclerosing Cholangitis or Cholangiocarcinoma

Evangelos Kalaitzakis; Michael J. Levy; Terumi Kamisawa; Gavin J. Johnson; Todd H. Baron; Mark Topazian; Naoki Takahashi; Atsushi Kanno; Kazuichi Okazaki; Naoto Egawa; Kazushige Uchida; Kashif Sheikh; Zahir Amin; Tooru Shimosegawa; Neomal S. Sandanayake; Nicholas I. Church; Michael H. Chapman; Stephen P. Pereira; Suresh T. Chari; George Webster

BACKGROUND & AIMS Distinction of immunoglobulin G4-associated cholangitis (IAC) from primary sclerosing cholangitis (PSC) or cholangiocarcinoma is challenging. We aimed to assess the performance characteristics of endoscopic retrograde cholangiography (ERC) for the diagnosis of IAC. METHODS Seventeen physicians from centers in the United States, Japan, and the United Kingdom, unaware of clinical data, reviewed 40 preselected ERCs of patients with IAC (n = 20), PSC (n = 10), and cholangiocarcinoma (n = 10). The performance characteristics of ERC for IAC diagnosis as well as the κ statistic for intraobserver and interobserver agreement were calculated. RESULTS The overall specificity, sensitivity, and interobserver agreement for the diagnosis of IAC were 88%, 45%, and 0.18, respectively. Reviewer origin, specialty, or years of experience had no statistically significant effect on reporting success. The overall intraobserver agreement was fair (0.74). The operating characteristics of different ERC features for the diagnosis of IAC were poor. CONCLUSIONS Despite high specificity of ERC for diagnosing IAC, sensitivity is poor, suggesting that many patients with IAC may be misdiagnosed with PSC or cholangiocarcinoma. Additional diagnostic strategies are likely to be vital in distinguishing these diseases.


British Journal of Cancer | 2011

A combination of serum leucine-rich α-2-glycoprotein 1, CA19-9 and interleukin-6 differentiate biliary tract cancer from benign biliary strictures.

Neomal S. Sandanayake; John Sinclair; Fausto Andreola; Michael H. Chapman; Aiqun Xue; George Webster; A. Clarkson; Anthony J. Gill; Ian D. Norton; Ross C. Smith; John F. Timms; Stephen P. Pereira

Background:Biliary tract cancer (BTC) and benign biliary strictures can be difficult to differentiate using standard tumour markers such as serum carbohydrate antigen 19-9 (CA19-9) as they lack diagnostic accuracy.Methods:Two-dimensional difference gel electrophoresis and tandem mass spectrometry were used to profile immunodepleted serum samples collected from cases of BTC, primary sclerosing cholangitis (PSC), immunoglobulin G4-associated cholangitis and healthy volunteers. The serum levels of one candidate protein, leucine-rich α-2-glycoprotein (LRG1), were verified in individual samples using enzyme-linked immunosorbent assay and compared with serum levels of CA19-9, bilirubin, interleukin-6 (IL-6) and other inflammatory markers.Results:We report increased LRG1, CA19-9 and IL-6 levels in serum from patients with BTC compared with benign disease and healthy controls. Immunohistochemical analysis also demonstrated increased staining of LRG1 in BTC compared with cholangiocytes in benign biliary disease. The combination of receiver operating characteristic (ROC) curves for LRG1, CA19-9 and IL-6 demonstrated an area under the ROC curve of 0.98. In addition, raised LRG1 and CA19-9 were found to be independent predictors of BTC in the presence of elevated bilirubin, C-reactive protein and alkaline phosphatase.Conclusion:These results suggest LRG1, CA19-9 and IL-6 as useful markers for the diagnosis of BTC, particularly in high-risk patients with PSC.


Liver International | 2011

R0 but not R1/R2 resection is associated with better survival than palliative photodynamic therapy in biliary tract cancer

Wolf-Rudiger Matull; Dipok Kumar Dhar; Lakshmana Ayaru; Neomal S. Sandanayake; Michael H. Chapman; Aruna Dias; John Bridgewater; George Webster; Jin J. Bong; Brian R. Davidson; Stephen P. Pereira

Background: There is a need for better management strategies to improve the survival and quality of life in patients with biliary tract cancer (BTC).


Journal of clinical and experimental hepatology | 2011

Circulating CYFRA 21-1 is a Specific Diagnostic and Prognostic Biomarker in Biliary Tract Cancer

Michael H. Chapman; Neomal S. Sandanayake; Fausto Andreola; Dipok Kumar Dhar; George Webster; James Dooley; Stephen P. Pereira

BACKGROUND: Biliary tract cancer (BTC) has a poor prognosis, in part related to difficulties in diagnosis. Cytokeratin 19 (CK19) is a constituent of the intermediate filament proteins of epithelial cells. CK19 fragments (CYFRA 21-1) are rarely identified in the blood of healthy individuals. We assessed the utility of CYFRA 21-1 as a diagnostic and prognostic marker of BTC. METHODS: Blood was prospectively collected from patients with benign biliary disease (n = 39), primary sclerosing cholangitis (n = 19), PSC-related cholangiocarcinoma (n = 6) and sporadic BTC (n = 60). CYFRA 21-1 levels were measured in duplicate by ELISA. RESULTS: CYFRA 21-1 (≥ 1.5 ng/mL) had a sensitivity of 56% and specificity of 88%, compared with figures of 79% and 78% for CA 19-9 (≥ 37U/mL). Using a higher cut-off of 3 ng/mL, CYFRA 21-1 had a sensitivity of 30% and specificity of 97%. Combination of CYFRA 21-1 (≥ 1.5 ng/mL) and CA 19-9 (≥ 37 U/mL) resulted in sensitivity and specificity of 45% and 96%. In contrast to CA 19-9, CYFRA 21-1 (≥ 3.0 ng/mL) alone was a strong predictor of prognosis (median survival 2 months vs 10 months, p = 0.001). CONCLUSION: Elevated circulating CYFRA 21-1 is a specific, but less sensitive diagnostic marker than CA 19-9, predicts a poor outcome and may act as a surrogate marker of circulating tumor cells in BTC. Further prospective studies of its utility in assessing operability and response to chemotherapy are needed.


Journal of Hepatology | 2012

Whole genome RNA expression profiling of endoscopic biliary brushings provides data suitable for biomarker discovery in cholangiocarcinoma

Michael H. Chapman; Robert Tidswell; James Dooley; Neomal S. Sandanayake; Virginie Cerec; Maesha Deheragoda; Alvin J.X. Lee; Charles Swanton; Fausto Andreola; Stephen P. Pereira

BACKGROUND & AIMS Molecular analyses of biliary brushings using microarray and qPCR have the potential to provide valuable information on the biology of biliary diseases. Microarray analysis of biliary strictures has rarely been applied to endoscopic biliary brushings. METHODS Biliary brushings were obtained from patients with benign and malignant biliary disease at the time of ERCP. Microarray analysis of mRNA isolated using brushings from 10 patients was validated for a selection of genes by qPCR using the same source mRNA and a second fresh set of nine biliary brushings as well as surgical resection tissue. Cultured cholangiocytes were used to assess the impact of bile or X-ray contrast solution on RNA quality. RESULTS RNA was of variable quantity (100-1500 ng) and poor quality (Agilent RNA Integrity Number (RIN)<5, estimated to be fragments 100 to 600 base pairs long). Reliable qPCR results required primer pairs designed to produce amplicons <130 bp. Differential gene expression by microarray analysis identified 1140 up-regulated genes and 1001 down-regulated genes between benign and malignant biliary strictures. The trends in a selection of 45 up-regulated genes, including various HOX genes, collagens, PVT1, MUC4, MUC5AC, and LEF1, were validated by qPCR using RNA from biliary strictures with a moderate to strong correlation coefficient between microarray and qPCR (r=0.41 to r=0.57). Immunohistochemistry of surgical resection tissues (n=23) showed elevated CD9, SERPINA3, and PNMA2 protein expression in cancer samples. CONCLUSIONS RNA isolated from biliary brushings is suitable for molecular analysis of biliary diseases using qPCR and microarray.


Cancer | 2013

Pyruvate kinase M2 is a novel diagnostic marker and predicts tumor progression in human biliary tract cancer.

Dipok Kumar Dhar; Steven W.M. Olde Damink; James Hal Brindley; Andrew Godfrey; Michael H. Chapman; Neomal S. Sandanayake; Fausto Andreola; Sybille Mazurek; Tayyaba Hasan; Massimo Malago; Stephen P. Pereira

The early diagnosis of biliary tract cancer (BTC) remains challenging, and there are few effective therapies. This study investigated whether the M2 isotype of pyruvate kinase (M2‐PK), which serves as the key regulator of cellular energy metabolism in proliferating cells, could play a role in the diagnosis and therapy of BTC.

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George Webster

University College London

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Fausto Andreola

University College London

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Zahir Amin

University College London

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