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Dive into the research topics where Susan K. Clark is active.

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Featured researches published by Susan K. Clark.


Journal of the American College of Cardiology | 2010

Prognostic Significance of Myocardial Fibrosis in Hypertrophic Cardiomyopathy

Rory O'Hanlon; Agata Grasso; Michael Roughton; James C. Moon; Susan K. Clark; Ricardo Wage; Jessica Webb; Meghana Kulkarni; Dana Dawson; Leena Sulaibeekh; Badri Chandrasekaran; Chiara Bucciarelli-Ducci; Ferdinando Pasquale; Martin R. Cowie; William J. McKenna; Mary N. Sheppard; Perry M. Elliott; Dudley J. Pennell; Sanjay Prasad

OBJECTIVES We investigated the significance of fibrosis detected by late gadolinium enhancement cardiovascular magnetic resonance for the prediction of major clinical events in hypertrophic cardiomyopathy (HCM). BACKGROUND The role of myocardial fibrosis in the prediction of sudden death and heart failure in HCM is unclear with a lack of prospective data. METHODS We assessed the presence and amount of myocardial fibrosis in HCM patients and prospectively followed them for the development of morbidity and mortality in patients over 3.1 +/- 1.7 years. RESULTS Of 217 consecutive HCM patients, 136 (63%) showed fibrosis. Thirty-four of the 136 patients (25%) in the fibrosis group but only 6 of 81 (7.4%) patients without fibrosis reached the combined primary end point of cardiovascular death, unplanned cardiovascular admission, sustained ventricular tachycardia or ventricular fibrillation, or appropriate implantable cardioverter-defibrillator discharge (hazard ratio [HR]: 3.4, p = 0.006). In the fibrosis group, overall risk increased with the extent of fibrosis (HR: 1.18/5% increase, p = 0.008). The risk of unplanned heart failure admissions, deterioration to New York Heart Association functional class III or IV, or heart failure-related death was greater in the fibrosis group (HR: 2.5, p = 0.021), and this risk increased as the extent of fibrosis increased (HR: 1.16/5% increase, p = 0.017). All relationships remained significant after multivariate analysis. The extent of fibrosis and nonsustained ventricular tachycardia were univariate predictors for arrhythmic end points (sustained ventricular tachycardia or ventricular fibrillation, appropriate implantable cardioverter-defibrillator discharge, sudden cardiac death) (HR: 1.30, p = 0.014). Nonsustained ventricular tachycardia remained an independent predictor of arrhythmic end points after multivariate analysis, but the extent of fibrosis did not. CONCLUSIONS In patients with HCM, myocardial fibrosis as measured by late gadolinium enhancement cardiovascular magnetic resonance is an independent predictor of adverse outcome. (The Prognostic Significance of Fibrosis Detection in Cardiomyopathy; NCT00930735).


Nature Genetics | 2013

Germline mutations affecting the proofreading domains of POLE and POLD1 predispose to colorectal adenomas and carcinomas

Claire Palles; Jean-Baptiste Cazier; Kimberley Howarth; Enric Domingo; Angela Jones; Peter Broderick; Zoe Kemp; Sarah L. Spain; Estrella Guarino; Israel Salguero; Amy Sherborne; Daniel Chubb; Luis Carvajal-Carmona; Yusanne Ma; Kulvinder Kaur; Sara E. Dobbins; Ella Barclay; Maggie Gorman; Lynn Martin; Michal Kovac; Sean Humphray; Anneke Lucassen; Christopher Holmes; David R. Bentley; Peter Donnelly; Jenny C. Taylor; Christos Petridis; Rebecca Roylance; Elinor Sawyer; David Kerr

Many individuals with multiple or large colorectal adenomas or early-onset colorectal cancer (CRC) have no detectable germline mutations in the known cancer predisposition genes. Using whole-genome sequencing, supplemented by linkage and association analysis, we identified specific heterozygous POLE or POLD1 germline variants in several multiple-adenoma and/or CRC cases but in no controls. The variants associated with susceptibility, POLE p.Leu424Val and POLD1 p.Ser478Asn, have high penetrance, and POLD1 mutation was also associated with endometrial cancer predisposition. The mutations map to equivalent sites in the proofreading (exonuclease) domain of DNA polymerases ɛ and δ and are predicted to cause a defect in the correction of mispaired bases inserted during DNA replication. In agreement with this prediction, the tumors from mutation carriers were microsatellite stable but tended to acquire base substitution mutations, as confirmed by yeast functional assays. Further analysis of published data showed that the recently described group of hypermutant, microsatellite-stable CRCs is likely to be caused by somatic POLE mutations affecting the exonuclease domain.


Gut | 2008

Guidelines for the clinical management of familial adenomatous polyposis (FAP)

Hans F. A. Vasen; G. Moslein; Alejandra del C. Alonso; Stefan Aretz; Inge Bernstein; Lucio Bertario; Ismael Blanco; Steffen Bülow; John Burn; Gabriel Capellá; Chrystelle Colas; Christoph Engel; Ian Frayling; Waltraut Friedl; Frederik J. Hes; Shirley Hodgson; Heikki Järvinen; Jukka-Pekka Mecklin; Pål Møller; T. Myrhoi; Fokko M. Nagengast; Y. Parc; Robin K. S. Phillips; Susan K. Clark; M. P. de Leon; Laura Renkonen-Sinisalo; Julian Roy Sampson; Astrid Stormorken; Sabine Tejpar; Huw Thomas

Background: Familial adenomatous polyposis (FAP) is a well-described inherited syndrome, which is responsible for <1% of all colorectal cancer (CRC) cases. The syndrome is characterised by the development of hundreds to thousands of adenomas in the colorectum. Almost all patients will develop CRC if they are not identified and treated at an early stage. The syndrome is inherited as an autosomal dominant trait and caused by mutations in the APC gene. Recently, a second gene has been identified that also gives rise to colonic adenomatous polyposis, although the phenotype is less severe than typical FAP. The gene is the MUTYH gene and the inheritance is autosomal recessive. In April 2006 and February 2007, a workshop was organised in Mallorca by European experts on hereditary gastrointestinal cancer aiming to establish guidelines for the clinical management of FAP and to initiate collaborative studies. Thirty-one experts from nine European countries participated in these workshops. Prior to the meeting, various participants examined the most important management issues according to the latest publications. A systematic literature search using Pubmed and reference lists of retrieved articles, and manual searches of relevant articles, was performed. During the workshop, all recommendations were discussed in detail. Because most of the studies that form the basis for the recommendations were descriptive and/or retrospective in nature, many of them were based on expert opinion. The guidelines described herein may be helpful in the appropriate management of FAP families. In order to improve the care of these families further, prospective controlled studies should be undertaken.


Gut | 2010

Peutz–Jeghers syndrome: a systematic review and recommendations for management

A Beggs; A. R. Latchford; Hans F. A. Vasen; G. Moslein; Alejandra del C. Alonso; Stefan Aretz; Lucio Bertario; Ismael Blanco; Steffen Bülow; John Burn; Gabriel Capellá; Chrystelle Colas; Waltraut Friedl; Pål Møller; Frederik J. Hes; Heikki Järvinen; Jukka-Pekka Mecklin; Fokko M. Nagengast; Y. Parc; Robin K. S. Phillips; Warren Hyer; M. Ponz de Leon; Laura Renkonen-Sinisalo; Julian Roy Sampson; Astrid Stormorken; Sabine Tejpar; Huw Thomas; Juul T. Wijnen; Susan K. Clark; S Hodgson

Peutz–Jeghers syndrome (PJS, MIM175200) is an autosomal dominant condition defined by the development of characteristic polyps throughout the gastrointestinal tract and mucocutaneous pigmentation. The majority of patients that meet the clinical diagnostic criteria have a causative mutation in the STK11 gene, which is located at 19p13.3. The cancer risks in this condition are substantial, particularly for breast and gastrointestinal cancer, although ascertainment and publication bias may have led to overestimates in some publications. Current surveillance protocols are controversial and not evidence-based, due to the relative rarity of the condition. Initially, endoscopies are more likely to be done to detect polyps that may be a risk for future intussusception or obstruction rather than cancers, but surveillance for the various cancers for which these patients are susceptible is an important part of their later management. This review assesses the current literature on the clinical features and management of the condition, genotype–phenotype studies, and suggested guidelines for surveillance and management of individuals with PJS. The proposed guidelines contained in this article have been produced as a consensus statement on behalf of a group of European experts who met in Mallorca in 2007 and who have produced guidelines on the clinical management of Lynch syndrome and familial adenomatous polyposis.


Gut | 2007

A Meta-analysis on the Influence of Inflammatory Bowel Disease on Pregnancy

Julie A. Cornish; Emile Kw Tan; Julian Teare; Teoh G. Teoh; Raj Rai; Susan K. Clark; Paris P. Tekkis

Background: Inflammatory bowel disease (IBD) has a typical onset during the peak reproductive years. Evidence of the risk of adverse pregnancy outcomes in IBD is important for the management of pregnancy to assist in its management. Aim: To provide a clear assessment of risk of adverse outcomes during pregnancy in women with IBD. Design: The Medline literature was searched to identify studies reporting outcomes of pregnancy in patients with IBD. Random-effect meta-analysis was used to compare outcomes between women with IBD and normal controls. Patients and setting: A total of 3907 patients with IBD (Crohn’s disease 1952 (63%), ulcerative colitis 1113 (36%)) and 320 531 controls were reported in 12 studies that satisfied the inclusion criteria. Results: For women with IBD, there was a 1.87-fold increase in incidence of prematurity (<37 weeks gestation; 95% CI 1.52 to 2.31; p<0.001) compared with controls. The incidence of low birth weight (<2500 g) was over twice that of normal controls (95% CI 1.38 to 3.19; p<0.001). Women with IBD were 1.5 times more likely to undergo caesarean section (95% CI 1.26 to 1.79; p<0.001), and the risk of congenital abnormalities was found to be 2.37-fold increased (95% CI 1.47 to 3.82; p<0.001). Conclusion: The study has shown a higher incidence of adverse pregnancy outcomes in patients with IBD. Further studies are required to clarify which women are at higher risk, as this was not determined in the present study. This has an effect on the management of patients with IBD during pregnancy, who should be treated as a potentially high-risk group.


The American Journal of Gastroenterology | 2008

The Risk of Oral Contraceptives in the Etiology of Inflammatory Bowel Disease: A Meta-Analysis

Julie A. Cornish; Emile Tan; Constantinos Simillis; Susan K. Clark; Julian Teare; Paris P. Tekkis

OBJECTIVES:Several environmental and genetic factors have been implicated to date in the development of Crohns disease (CD) and ulcerative colitis (UC). The aim of this study was to provide a quantification of the risk of oral contraceptive pill (OCP) use in the etiology of inflammatory bowel disease.METHODS:A literature search was performed to identify comparative studies reporting on the association of oral contraceptive use in the etiology of UC and CD between 1983 and 2007. A random-effect meta-analysis was used to compare the incidence of UC or CD between the patients exposed to the OCP and nonexposed patients. The results were adjusted for smoking.RESULTS:A total of 75,815 patients were reported on by 14 studies, with 36,797 exposed to OCP and 39,018 nonexposed women. The pooled relative risk (RR) for CD for women currently taking the OCP was 1.51 (95% confidence interval [CI] 1.17–1.96, P = 0.002), and 1.46 (95% CI 1.26–1.70, P < 0.001), adjusted for smoking. The RR for UC in women currently taking the OCP was 1.53 (95% CI 1.21–1.94, P = 0.001), and 1.28 (95% CI 1.06–1.54, P = 0.011), adjusted for smoking. The RR for CD increased with the length of exposure to OCP. Moreover, although the RR did not reduce once the OCP was stopped, it was no longer significant once the OCP was stopped (CI contains 1), both for CD and for UC.CONCLUSIONS:This study provides evidence of an association between the use of oral contraceptive agents and development of IBD, in particular CD. The study also suggests that the risk for patients who stop using the OCP reverts to that of the nonexposed population.


Diseases of The Colon & Rectum | 2007

The effect of restorative proctocolectomy on sexual function, urinary function, fertility, pregnancy and delivery: a systematic review.

Julie A. Cornish; Emile Tan; Julian Teare; Teoh G. Teoh; Raj Rai; Ara Darzi; Paraskeva Paraskevas; Susan K. Clark; Paris P. Tekkis

PurposeThis study was designed to evaluate the effect of restorative proctocolectomy on sexual function, urinary function, fertility, pregnancy, and delivery in patients with ulcerative colitis.MethodsA systematic literature search was performed of articles published between 1980 and 2005 on patients undergoing restorative proctocolectomy for ulcerative colitis reporting data on the outcomes of interest. A random-effect, meta-analytical model was used for pooled estimates and 95 percent confidence intervals.ResultsA total of 22 studies, with 1,852 females, were included. Infertility rate was 12 percent before restorative proctocolectomy and 26 percent after, among 945 patients in seven studies. The incidence of sexual dysfunction was 8 percent preoperatively and 25 percent postoperatively (7 studies, n = 419). Two studies (n = 62) reported no urinary dysfunction in patients undergoing restorative proctocolectomy. There was an increased incidence of cesarean section after restorative proctocolectomy. During the third trimester of pregnancy, there was an increase in stool frequency by 1.15 stools per day compared with before pregnancy frequency (n = 49 95 percent confidence interval, 0.28–2.03 P = 0.01 chi-squared statistic, 0.04 P = 0.84). No significant differences were seen in pouch function after vaginal delivery (n = 456; weighted mean difference, 0.23; 95 percent confidence interval, 0.43–0.88; P = 0.49; chi-squared statistic, 1.29; P = 0.26).ConclusionsThe incidence of dyspareunia increases after restorative proctocolectomy. There was a decrease in fertility after restorative proctocolectomy. Pregnancy after restorative proctocolectomy was not associated with an increase in complications. There was an increase in stool frequency and pad usage during the third trimester. Vaginal delivery is safe after restorative proctocolectomy. Pouch function after delivery returns to pregestational function within six months.


Gut | 2010

Eicosapentaenoic acid reduces rectal polyp number and size in familial adenomatous polyposis

Nicholas J. West; Susan K. Clark; Robin K. S. Phillips; John M Hutchinson; Roger J. Leicester; Andrea Belluzzi; Mark A. Hull

Objective The omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) has anticolorectal cancer activity in vitro and in preclinical models. The present study tested whether a novel, enteric-coated formulation of EPA, as the free fatty acid (EPA-FFA), has chemopreventative efficacy in patients with familial adenomatous polyposis (FAP), in a randomised, double-blind, placebo-controlled trial. Methods Patients undergoing endoscopic surveillance of their retained rectum postcolectomy were randomised to EPA-FFA (SLA Pharma) 2 g daily or placebo for 6 months. The number and size of polyps in an area of mucosa defined by a tattoo were determined before and after intervention. Global rectal polyp burden was scored (−1, 0, +1) by examination of video endoscopy records. Mucosal fatty acid content was measured by gas chromatography–mass spectrometry. Results 55 patients with FAP were evaluated by an intention-to-treat analysis (EPA-FFA 28, placebo 27). Treatment with EPA-FFA for 6 months was associated with a mean 22.4% (95% CI 5.1% to 39.6%) reduction in polyp number (p=0.012) and a 29.8% (3.6% to 56.1%) decrease in the sum of polyp diameters (p=0.027). Global polyp burden worsened over 6 months in the placebo group (−0.34) unlike the EPA-FFA group (+0.09, difference 0.42 (0.10–0.75), p=0.011). EPA-FFA treatment led to a mean 2.6-fold increase in mucosal EPA levels (p=0.018 compared with placebo). EPA-FFA was well tolerated with an incidence of adverse events similar to placebo. Conclusions EPA-FFA has chemopreventative efficacy in FAP, to a degree similar to that previously observed with selective cyclo-oxygenase-2 inhibitors. EPA holds promise as a colorectal cancer chemoprevention agent with a favourable safety profile. Clinical trial number NCT00510692.


Familial Cancer | 2006

Current ideas in desmoid tumours

N. Julian H. Sturt; Susan K. Clark

Desmoid tumours are rare neoplasms of fibroblastic origin which arise with disproportionate frequency in patients with familial adenomatous polyposis (FAP). They are thought to develop in about 10–25% of FAP patients and may be the leading cause of death amongst those who have undergone colectomy. Risk factors include trauma, having a distal germline APC mutation, having a family history of desmoids, and probably oestrogens. In very high-risk individuals there may be a case for delay of colectomy or chemoprophylaxis at the time of surgery. Desmoids are now known to be true neoplasms but with normal telomere length and telomerase activity. FAP-associated tumours seem to carry biallelic APC mutations, one of which lies in the distal part of the gene. Such loss of wild-type APC seems to occur relatively late in tumour development. It is likely that β-catenin plays an important role in tumourigenesis. FAP-associated desmoids tend to arise in the abdomen or abdominal wall. CT scanning gives the best information on tumour anatomy whilst T2-weighted MRI indicates likely behaviour. Treatment may simply consist of observation. Otherwise, usual first-line therapy is with sulindac with or without an anti-oestrogen. Cytotoxic chemotherapy is an option in unresectable tumours. Surgery is a reasonable first-line treatment in abdominal wall tumours but is risky for intra-abdominal tumours and may necessitate massive small bowel resection. Desmoids are the greatest remaining challenge in the management of FAP and further research into their aetiology needs to be combined with multicentre clinical trials of new treatments in order to improve management of the disease.


British Journal of Surgery | 2013

Consensus statement on the multidisciplinary management of patients with recurrent and primary rectal cancer beyond total mesorectal excision planes.

Aneel Bhangu; J. Beynon; G. Brown; G. Chang; P. Das; A. Desai; Francis A. Frizelle; R. Glynne-Jones; R. Goldin; Hawkins; Alexander G. Heriot; S. Laurberg; A. Mirnezami; R. J. Nicholls; P. M. Sagar; Paris P. Tekkis; T. Vuong; M. Wilson; S.M. Ali; Anthony Antoniou; P. Bose; K. Boyle; G. Branagan; D. Burling; Susan K. Clark; P. Colquhuon; C.H. Crane; Ara Darzi; M. Davies; Conor P. Delaney

The management of primary rectal cancer beyond total mesorectal excision planes (PRC‐bTME) and recurrent rectal cancer (RRC) is challenging. There is global variation in standards and no guidelines exist. To achieve cure most patients require extended, multivisceral, exenterative surgery, beyond conventional total mesorectal excision planes. The aim of the Beyond TME Group was to achieve consensus on the definitions and principles of management, and to identify areas of research priority.

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Paris P. Tekkis

The Royal Marsden NHS Foundation Trust

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Ailsa Hart

Imperial College London

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R. J. Nicholls

University of Birmingham

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Omar Faiz

Imperial College London

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J. Landy

Imperial College London

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