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Dive into the research topics where John A. C. Buckels is active.

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Featured researches published by John A. C. Buckels.


Annals of Surgery | 2001

Influence of resection margins on survival for patients with pancreatic cancer treated by adjuvant chemoradiation and/or chemotherapy in the ESPAC-1 randomized controlled trial

John P. Neoptolemos; Deborah D. Stocken; Janet A. Dunn; Jennifer Almond; Hans G. Beger; Paolo Pederzoli; Claudio Bassi; Christos Dervenis; Laureano Fernández-Cruz; François Lacaine; John A. C. Buckels; Mark Deakin; Fawzi Adab; Robert Sutton; Clem W. Imrie; Ingemar Ihse; Tibor Tihanyi; Attila Oláh; Sergio Pedrazzoli; D. Spooner; David Kerr; Helmut Friess; Markus W. Büchler

ObjectiveTo assess the influence of resection margins on survival for patients with resected pancreatic cancer treated within the context of the adjuvant European Study Group for Pancreatic Cancer-1 (ESPAC-1) study. Summary Background DataPancreatic cancer is associated with a poor long-term survival rate of only 10% to 15% after resection. Patients with positive microscopic resection margins (R1) have a worse survival, but it is not known how they fare in adjuvant studies. MethodsESPAC-1, the largest randomized adjuvant study of resectable pancreatic cancer ever performed, set out to look at the roles of chemoradiation and chemotherapy. Randomization was stratified prospectively by resection margin status. ResultsOf 541 patients with a median follow-up of 10 months, 101 (19%) had R1 resections. Resection margin status was confirmed as an influential prognostic factor, with a median survival of 10.9 months for R1 versus 16.9 months months for patients with R0 margins. Resection margin status remained an independent factor in a Cox proportional hazards model only in the absence of tumor grade and nodal status. There was a survival benefit for chemotherapy but not chemoradiation, irrespective of R0/R1 status. The median survival was 19.7 months with chemotherapy versus 14.0 months without. For patients with R0 margins, chemotherapy produced longer survival compared with to no chemotherapy. This difference was less apparent for the smaller subgroup of R1 patients, but there was no significant heterogeneity between the R0 and R1 groups. ConclusionsResection margin-positive pancreatic tumors represent a biologically more aggressive cancer; these patients benefit from resection and adjuvant chemotherapy but not chemoradiation. The magnitude of benefit for chemotherapy treatment is reduced for patients with R1 margins versus those with R0 margins. Patients with R1 tumors should be included in future trials of adjuvant treatments and randomization and analysis should be stratified by this significant prognostic factor.


Gut | 2008

Needle track seeding following biopsy of liver lesions in the diagnosis of hepatocellular cancer: a systematic review and meta-analysis

Michael A Silva; Bassem Hegab; Christopher J Hyde; Boliang Guo; John A. C. Buckels; Darius F. Mirza

Background: Needle biopsy of a suspicious liver lesion could guide management in the setting of equivocal imaging and serology, although it is not recommended generally because there is the possibility of tumour dissemination outside the liver. The incidence of needle track seeding following biopsy of a suspicious liver lesion is ill-defined, however. Methods: A systematic review and meta-analysis of observational studies published before March 2007 was performed. Studies that reported on needle tract seeding following biopsy of suspicious liver lesions were identified. Lesions suspected of being hepatocelleular cancer (HCC) were considered. Data on the type of needle biopsy, diagnosis, incidence of needle track seeding duration to seeding, follow-up and impact on outcome were tabulated. Results: Eight studies identified by systematic review on biopsy of HCC were included in a meta-analysis. The pooled estimate of a patient with seeding per 100 patients with HCC was 0.027 (95% confidence interval (CI) 0.018 to 0.040). There was no difference whether a fixed or random effects model was used. Q was 4.802 with 7 degrees of freedom, p = 0.684; thus the observed heterogeneity was compatible with variation by chance alone. The pooled estimate of a patient with seeding per 100 patients per year was 0.009 (95% CI 0.006 to 0.013), p = 0.686. Conclusions: In this systematic review we have shown that the incidence of needle tract tumour seeding following biopsy of a HCC is 2.7% overall, or 0.9% per year.


The Lancet | 2006

3-month and 12-month mortality after first liver transplant in adults in Europe: predictive models for outcome

Andrew K. Burroughs; Caroline Sabin; Keith Rolles; V. Delvart; Vincent Karam; John A. C. Buckels; John O'Grady; Denis Castaing; Jürgen Klempnauer; Neville V. Jamieson; Peter Neuhaus; Jan Lerut; Jean de Ville de Goyet; S. Pollard; Mauro Salizzoni; Xavier Rogiers; Ferdinand Mühlbacher; Juan Carlos Garcia Valdecasas; Christopher Broelsch; Daniel Jaeck; Joaquín Berenguer; Enrique Moreno González; René Adam

BACKGROUND Mortality after liver transplantation depends on heterogeneous recipient and donor factors. Our aim was to assess risk of death and to develop models to help predict mortality after liver transplantation. METHODS We analysed data from 34,664 first adult liver transplants from the European Liver Transplant Registry to identify factors associated with mortality at 3-months (n=21,605 in training dataset) and 12-months (n=18,852 in training dataset) after transplantation. We used multivariable logistic regression models to generate mortality scores for each individual, and assessed model discrimination and calibration on an independent validation dataset (n=9489 for 3-month model and n=8313 for 12-month model). FINDINGS 2540 of 21,605 (12%) individuals in the 3-month training sample had died by 3 months. Compared with those transplanted in 2000-03, those transplanted earlier had a higher risk of death. Increased mortality at 3-months post-transplantation was associated with acute liver failure (adjusted odds ratio 1.61), donor age older than 60 years (1.16), compatible (1.22) or incompatible (2.07) donor-recipient blood group, older recipient age (1.12 per 5 years), split or reduced graft (1.96), total ischaemia time of longer than 13 h (1.38), and low United Network for Organ Sharing score (score 1: 2.43; score 2: 1.67). However, cirrhosis with hepatocellular carcinoma, alcohol cirrhosis, hepatitis C or primary biliary cirrhosis, donor age 40 years or younger, or less, hepatitis B, and larger size of transplant centre (> or = 70 transplants per year) were associated with improved early outcomes. The 3-month mortality score discriminated well between those who did and did not die in the validation sample (C statistic=0.688). We noted similar findings for 12-month mortality, although deaths were generally underestimated at this timepoint. INTERPRETATION The 3-month and 12-month mortality models can be effectively used to assess outcomes both within and between centres. Furthermore, the models provide a means of assessing the risk of post-transplantation mortality, giving clinicians important data on which to base strategic decisions about transplant policy in particular individuals or groups.


The Lancet | 2003

Intrahepatic arterial versus intravenous fluorouracil and folinic acid for colorectal cancer liver metastases: a multicentre randomised trial.

David Kerr; C. S. McArdle; Jonathan A. Ledermann; I. Taylor; David J Sherlock; Peter M. Schlag; John A. C. Buckels; David Mayer; Dionne Cain; Richard Stephens

BACKGROUND The liver is the most frequent site for metastases of colorectal cancer, which is the second largest contributor to cancer deaths in Europe. We did a randomised trial to compare an intrahepatic arterial (IHA) fluorouracil and folinic acid regimen with the standard intravenous de Gramont fluorouracil and folinic acid regimen for patients with adenocarcinoma of the colon or rectum, with metastases confined to the liver. METHODS We randomly allocated 290 patients from 16 centres to receive either intravenous chemotherapy (folinic acid 200 mg/m2, fluorouracil bolus 400 mg2 and 22-h infusion 600 mg/m2, day 1 and 2, repeated every 14 days), or IHA chemotherapy designed to be equitoxic (folinic acid 200 mg/m2, fluorouracil 400 mg/m2 over 15 mins and 22-h infusion 1600 mg/m2, day 1 and 2, repeated every 14 days). The primary endpoint was overall survival, and analysis was by intention to treat. FINDINGS 50 (37%) patients allocated to IHA did not start their treatment, and another 39 (29%) had to stop before receiving six cycles of treatment because of catheter failure. The IHA group received a median of two cycles (0-6), compared with 8.5 (6-12) for the intravenous group. 45 (51%) IHA patients who did not start or did not receive six cycles switched to intravenous treatment. In both groups, grade 3 or 4 toxicity was uncommon. Median overall survival was 14.7 months for the IHA group and 14.8 months for the intravenous group (hazard ratio 1.04 [95% CI 0.80-1.33], log-rank test p=0.79). Similarly, there was no significant difference in progression-free survival. INTERPRETATION Our results showed no evidence of an advantage in progression-free survival or overall survival for the IHA group; thus continued use of this regimen cannot be recommended outside of a clinical trial.


Liver Transplantation | 2006

Hepatic artery thrombosis following orthotopic liver transplantation: a 10-year experience from a single centre in the United Kingdom.

Michael A. Silva; Periyathambi S. Jambulingam; Bridget K. Gunson; David Mayer; John A. C. Buckels; Darius F. Mirza; Simon R. Bramhall

Hepatic artery thrombosis (HAT) occurs in 3–9% of all liver transplants and acute graft loss is a possible sequelae. We present our experience in the management of HAT over a 10‐year period. Prospectively collected data from April 1994 to April 2004 were analyzed. There were 1,257 liver transplants, 669 males, median age 51 (16–73) years. There were 61 (4.9%) cases of HAT. Early HAT occurred in 21 (1.8%). Thirty six had graft dysfunction, 11 required a regraft, and 14 died. Positive CMV serology in the donor, cold ischemia time, duration of operation, transfusions of more than 6 units of blood, and 15 units of plasma, an aortic conduit for arterial reconstruction, Roux‐en‐Y biliary reconstructions, regrafts and relaparotomy were associated with HAT. At multivariate analysis, type of biliary anastomosis was the only significant factor associated with HAT. Split or reduced liver graft were not risk factors for HAT. Number of hepatic arteries requiring multiple arterial anastomosis was not a risk for HAT. HAT resulted in a reduction in overall survival post liver transplantation. The incidence of HAT was 4.9%; with 1.8% early HAT and HAT impacted on survival. Surgical technique was not an aetiological factor for HAT. In conclusion, while a Roux‐en‐Y biliary reconstruction was an independent risk factor for HAT, cold ischemia and operative times, the use of blood and plasma and the use of aortic conduits in arterial reconstruction were associated with HAT. Regrafts and reoperation were also identified risk factors. Liver Transpl 12:146–151, 2006.


Transplantation | 2003

Colorectal cancer in patients with inflammatory Bowel disease after liver transplantation for primary sclerosing cholangitis

Alonso Vera; Bridget K. Gunson; Val Ussatoff; Peter Nightingale; Daniel Candinas; Simon Radley; A. David Mayer; John A. C. Buckels; Paul McMaster; James Neuberger; Darius F. Mirza

Background. Patients with primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) may have an increased risk of developing colorectal cancer (CRC) after liver transplantation (LT). We evaluated our patients with PSC after LT to identify risk factors for CRC and its impact on survival. Patients and Methods. A total of 152 patients (108 men, 100 with IBD) with PSC who underwent 173 LTs between 1986 and May 2000 were analyzed in three groups: (1) PSC without IBD (n=52); (2) PSC with colectomy (pre-LT and at LT) (n=17, colectomy pre-LT in 13 and simultaneous colectomy at LT in four); and (3) PSC with IBD and an intact colon (n=83). The following factors were studied: age, gender, liver, and renal biochemistry, international normalized ratio, Child-Pugh stage, operative time, blood use, hospital stay, immunosuppression, risk of CRC, retransplantation rate, and mortality. Results. The incidence of CRC after LT was 5.3% (8/152) compared with 0.6% (7/1,184) in non-PSC cases (P <0.001). All CRCs in the PSC group were in patients with IBD and an intact colon. The cumulative risk of developing CRC in the 83 patients with an intact colon and IBD was 14% and 17% after 5 and 10 years, respectively (PSC non-IBD group 0% risk after 10 years, P <0.06). The multivariate analysis showed three significant variables related to the risk of developing CRC: colonic dysplasia after LT (P <0.0003), duration of colitis more than 10 years (P <0.002), and pancolitis (P <0.004). The cause of death in patients with CRC was cancer related in 75% of cases with a reduced 5-year survival of 55% versus 75% without CRC (not significant). Conclusion. Patients with PSC undergoing LT with a long history of ulcerative colitis and pancolitis have an increased risk of developing CRC with reduced survival. We advocate long-term aggressive colonic surveillance and colectomy in selected high-risk patients with longstanding severe colitis.


Annals of Surgical Oncology | 2007

A Randomized Phase 2 Trial of Neoadjuvant Chemotherapy in Resectable Pancreatic Cancer: Gemcitabine Alone Versus Gemcitabine Combined with Cisplatin

Daniel H. Palmer; Deborah D. Stocken; Helen Hewitt; Catherine E. Markham; A. Bassim Hassan; Philip J. Johnson; John A. C. Buckels; Simon R. Bramhall

BackgroundSurvival after surgery for pancreas cancer remains low. This improves with adjuvant chemotherapy, but up to 30% patients do not receive the prescribed treatment. Neoadjuvant therapy may increase the proportion of patients who receive all treatment components, may downstage disease before surgery, and may provide early treatment of micrometastases. This randomized phase 2 study compares gemcitabine-based chemotherapy regimens to identify the most promising regimen for future study.MethodsFifty patients with potentially resectable pancreas lesions were enrolled onto the study. Twenty-four patients were randomized to gemcitabine (1000 mg/m2) every 7 days for 43 days; 26 patients were randomized to gemcitabine (1000 mg/m2) and cisplatin (25 mg/m2), 7 to the original schedule (omitting day 22) and 19 to a revised schedule due to neutropenia (omitting days 15 and 36). The primary outcome measure was resection rate.ResultsPatients who were allocated to gemcitabine received a median of 85% of the planned dose. Patients who were allocated to combination treatment received a median of 88% and 92% of the planned gemcitabine and cisplatin doses, respectively. There were 10 episodes of grade III/IV hematological toxicity in each group. Twenty-seven patients (54%) underwent pancreatic resection, 9 (38%) in the gemcitabine arm and 18 (70%) in the combination arm, with no increase in surgical complications. To date, 34 patients (68%) have died. Twelve-month survival for the gemcitabine and combination groups was 42% and 62%.ConclusionsChemotherapy can be safely administered before pancreatic surgery. Combination therapy with gemcitabine and cisplatin is associated with a high resection rate and an encouraging survival rate, suggesting that further study is warranted.


Transplantation | 1993

Steroid withdrawal from long-term immunosuppression in liver allograft recipients.

Robert Padbury; Bridget K. Gunson; Bertrand Dousset; Stefan G. Hubscher; John A. C. Buckels; James Neuberger; Elwyn Elias; Paul McMaster

Corticosteroids were withdrawn from the immunosuppressive regimen of 168/197 (85%) of liver transplant patients who survived for more than three months. In 14, steroids were restarted for reasons other than rejection. The remaining 154 patients were evaluated for the occurrence of rejection and graft loss. Risk factors for the development of rejection after steroid withdrawal were assessed. There were 13 episodes of rejection in 12 (7.8%) grafts; 7 (4.5%) experienced acute cellular rejection, and 6 (3.9%) developed chronic ductopenic rejection. All cases of acute rejection resolved with high-dose steroids. Graft and patient loss due to chronic rejection was 3 (1.9%) and 2 (1.3%), respectively. Chronic rejection resolved in 1 patient, 1 was successfully retransplanted, and in the other 2 the principal cause of death was recurrent tumor. None of the risk factors examined (primary indication for transplant, severity of previous acute rejection, use of OKT3, retransplantation, ABO blood group donor/recipient match, CMV infection, and CsA mono versus CsA and AZA double therapy) were associated with the development of chronic rejection poststeroid withdrawal. The prevalence of side effects, after steroid withdrawal, was low; 66% of patients never required antihypertensive medication; 14% experienced a significant septic episode, and only 4 died with sepsis as the major factor. There were no fungal sepsis and no new cases of diabetes. Withdrawal of corticosteroids after 3 months can be successfully achieved in the majority of liver allograft recipients and is associated with a low rate of rejection, graft loss, and complications attributable to immunosuppressive medication.


Diabetes | 1993

Metabolic Effects of Cyclosporin A and FK 506 in Liver Transplant Recipients

Andrew J. Krentz; Bertrand Dousset; David Mayer; Paul McMaster; John A. C. Buckels; Robert Cramb; Janet Smith; Malcolm Nattrass

Postoperative diabetes is a reported feature of the immunosuppressive agents cyclosporin A and FK 506. To date, however, no randomized comparative studies of the metabolic effects of these two drugs have been performed. In this study, extended (300 min) oral glucose tolerance tests (75 g) were performed a median of 8 mo (range 5–9 mo) postoperatively in 20 clinically stable liver transplant recipients randomly allocated to maintenance immunosuppression with either cyclosporin A (with or without azathioprine) or FK 506. None of the patients had clinically overt diabetes antedating transplantation. To avoid the confounding effects of corticosteroids, prednisolone was withdrawn at least 6 wk beforehand in each case. Ten healthy volunteers matched for age and body mass index served as control subjects. Overall blood glucose concentrations after the glucose challenge were significantly elevated in both groups of transplant recipients (P < 0.005 and P < 0.001 for cyclosporin A and FK 506 treatment groups, respectively) compared with the healthy control subjects. Venous whole-blood glucose concentration (mean ± SE) 120 min after the ingestion of oral glucose was significantly higher in both the cyclosporin A (P < 0.05) and FK 506 (P < 0.01) treatment groups compared with the control subjects (6.6 ± 0.5 vs. 8.8 ± 0.9 vs. 5.2 ± 0.2 mM, respectively). According to 1985 WHO criteria, 4 of 10 cyclosporin A-treated patients had impaired glucose tolerance, whereas 3 of 10 FK 506–treated patients had diabetes with 4 others having impaired glucose tolerance. Overall plasma immunoreactive insulin concentrations were significantly elevated in both the cyclosporin A (P < 0.05) and FK 506 (P < 0.01) groups, as were C-peptide concentrations (P < 0.02 and P < 0.01, respectively). By contrast, fasting lactate concentrations were significantly lower (P < 0.05) in the transplant patients compared with the control subjects. Total blood ketone body concentrations were slightly higher in both transplant groups with an increased ratio of 3-hydroxybutryate:acetoacetate in the cyclosporin A–treated (P < 0.01) and FK 506–treated (P < 0.02) patients. In conclusion, successful liver transplantation in humans is associated with significant postoperative glucose intolerance and hyperinsulinemia. These metabolic abnormalities are independent of corticosteroid therapy and are more pronounced in patients treated with FK 506 than in comparable patients receiving cyclosporin A with or without azathioprine. Alterations in the circulating ketone body ratio suggest a relatively more reduced hepatic intramitochondrial redox state in liver transplant recipients treated with these immunosuppressive agents.


Transplantation | 2001

Delayed hepatic artery thrombosis in adult orthotopic liver transplantation-a 12-year experience.

Shantanu Bhattacharjya; Bridget K. Gunson; Darius F. Mirza; David Mayer; John A. C. Buckels; Paul McMaster; James Neuberger

BACKGROUND Although the clinical features of early hepatic artery thrombosis (HAT) are well defined, the features of delayed (more than 4 weeks after transplantation) hepatic artery thrombosis are less clearly defined. The aim of our study was to identify risk factors, clinical presentation, and outcome of management of delayed hepatic artery thrombosis (HAT) after liver transplant (LTx). METHODS An analysis of prospectively collected data of all patients transplanted from 1986 to 1998 was performed. The importance of recipient (age, sex, primary indication for LTx, cytomegalovirus status, and intraabdominal sepsis) and donor factors (donor age, cold ischemia time, and donor cytomegalovirus status), modes of presentation, and outcome of treatment (biliary reconstruction/stenting, regraft, vascular reconstruction, observation) were analyzed. RESULTS Delayed HAT was seen in 31/1097 adult LTx recipients (incidence 2.8%). No recipient or donor factors were identified as risk factors. A total of 16 patients were symptomatic at presentation (HAT diagnosed on abdominal ultrasound). Six patients had recurrent episodes of cholangitis, four had cholangitis with a stricture, four had cholangitis and intrahepatic abscesses, and two had bile leaks. Biliary reconstruction was done in six patients (all of whom subsequently required a regraft), vascular reconstruction was performed in two patients (one regrafted and one died shortly after), four patients with cholangitis and stricture on presentation had a biliary stent (all four were later regrafted). A total of 16 patients were regrafted, 9 are alive, 5 died within 6 months (septic at time of LTx), 1 died after 1 year, and 1 died after 2 years. Fifteen patients were asymptomatic and detected on routine screening. 5 have remained asymptomatic and are still alive, 1 developed a biliary stricture that was stented and is alive 105 months later, 4 had recurrence of the original disease, 3 developed progressive graft failure and were listed for transplant but died before regraft due to overwhelming sepsis and hepatic encephalopathy. Two patients died due to nonbiliary sepsis. CONCLUSIONS Delayed HAT is a rare complication of LTx that may present with biliary sepsis, or remain asymptomatic. Biliary or vascular reconstructions do not increase graft survival. Of the patients who were clinically silent on presentation, 20% developed progressive graft failure requiring a second transplant. A total of 33% survived in the long-term without a second transplant. Ongoing severe sepsis at the time of regraft results in poor survival.

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Darius F. Mirza

Queen Elizabeth Hospital Birmingham

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Simon R. Bramhall

Queen Elizabeth Hospital Birmingham

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David Mayer

Queen Elizabeth Hospital Birmingham

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Paul McMaster

University of Birmingham

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A. D. Mayer

Queen Elizabeth Hospital Birmingham

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P. McMaster

Queen Elizabeth Hospital Birmingham

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A. David Mayer

Queen Elizabeth Hospital Birmingham

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Elwyn Elias

Queen Elizabeth Hospital Birmingham

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James Neuberger

Queen Elizabeth Hospital Birmingham

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